Initial commit; kernel source import

drivers/pwm/Kconfig

@@ -0,0 +1,204 @@
+menuconfig PWM
+	bool "Pulse-Width Modulation (PWM) Support"
+	help
+	  Generic Pulse-Width Modulation (PWM) support.
+
+	  In Pulse-Width Modulation, a variation of the width of pulses
+	  in a rectangular pulse signal is used as a means to alter the
+	  average power of the signal. Applications include efficient
+	  power delivery and voltage regulation. In computer systems,
+	  PWMs are commonly used to control fans or the brightness of
+	  display backlights.
+
+	  This framework provides a generic interface to PWM devices
+	  within the Linux kernel. On the driver side it provides an API
+	  to register and unregister a PWM chip, an abstraction of a PWM
+	  controller, that supports one or more PWM devices. Client
+	  drivers can request PWM devices and use the generic framework
+	  to configure as well as enable and disable them.
+
+	  This generic framework replaces the legacy PWM framework which
+	  allows only a single driver implementing the required API. Not
+	  all legacy implementations have been ported to the framework
+	  yet. The framework provides an API that is backward compatible
+	  with the legacy framework so that existing client drivers
+	  continue to work as expected.
+
+	  If unsure, say no.
+
+if PWM
+
+config PWM_AB8500
+	tristate "AB8500 PWM support"
+	depends on AB8500_CORE && ARCH_U8500
+	help
+	  Generic PWM framework driver for Analog Baseband AB8500.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-ab8500.
+
+config PWM_ATMEL_TCB
+	tristate "Atmel TC Block PWM support"
+	depends on ATMEL_TCLIB && OF
+	help
+	  Generic PWM framework driver for Atmel Timer Counter Block.
+
+	  A Timer Counter Block provides 6 PWM devices grouped by 2.
+	  Devices in a given group must have the same period.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-atmel-tcb.
+
+config PWM_BFIN
+	tristate "Blackfin PWM support"
+	depends on BFIN_GPTIMERS
+	help
+	  Generic PWM framework driver for Blackfin.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-bfin.
+
+config PWM_IMX
+	tristate "i.MX PWM support"
+	depends on ARCH_MXC
+	help
+	  Generic PWM framework driver for i.MX.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-imx.
+
+config PWM_JZ4740
+	tristate "Ingenic JZ4740 PWM support"
+	depends on MACH_JZ4740
+	help
+	  Generic PWM framework driver for Ingenic JZ4740 based
+	  machines.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-jz4740.
+
+config PWM_LPC32XX
+	tristate "LPC32XX PWM support"
+	depends on ARCH_LPC32XX
+	help
+	  Generic PWM framework driver for LPC32XX. The LPC32XX SOC has two
+	  PWM controllers.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-lpc32xx.
+
+config PWM_MXS
+	tristate "Freescale MXS PWM support"
+	depends on ARCH_MXS && OF
+	select STMP_DEVICE
+	help
+	  Generic PWM framework driver for Freescale MXS.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-mxs.
+
+config PWM_PUV3
+	tristate "PKUnity NetBook-0916 PWM support"
+	depends on ARCH_PUV3
+	help
+	  Generic PWM framework driver for PKUnity NetBook-0916.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-puv3.
+
+config PWM_PXA
+	tristate "PXA PWM support"
+	depends on ARCH_PXA
+	help
+	  Generic PWM framework driver for PXA.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-pxa.
+
+config PWM_SAMSUNG
+	tristate "Samsung PWM support"
+	depends on PLAT_SAMSUNG
+	help
+	  Generic PWM framework driver for Samsung.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-samsung.
+
+config PWM_SPEAR
+	tristate "STMicroelectronics SPEAr PWM support"
+	depends on PLAT_SPEAR
+	depends on OF
+	help
+	  Generic PWM framework driver for the PWM controller on ST
+	  SPEAr SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-spear.
+
+config PWM_TEGRA
+	tristate "NVIDIA Tegra PWM support"
+	depends on ARCH_TEGRA
+	help
+	  Generic PWM framework driver for the PWFM controller found on NVIDIA
+	  Tegra SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-tegra.
+
+config  PWM_TIECAP
+	tristate "ECAP PWM support"
+	depends on SOC_AM33XX || ARCH_DAVINCI_DA8XX
+	help
+	  PWM driver support for the ECAP APWM controller found on AM33XX
+	  TI SOC
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-tiecap.
+
+config  PWM_TIEHRPWM
+	tristate "EHRPWM PWM support"
+	depends on SOC_AM33XX || ARCH_DAVINCI_DA8XX
+	help
+	  PWM driver support for the EHRPWM controller found on AM33XX
+	  TI SOC
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-tiehrpwm.
+
+config  PWM_TIPWMSS
+	bool
+	default y if SOC_AM33XX && (PWM_TIECAP || PWM_TIEHRPWM)
+	help
+	  PWM Subsystem driver support for AM33xx SOC.
+
+	  PWM submodules require PWM config space access from submodule
+	  drivers and require common parent driver support.
+
+config PWM_TWL
+	tristate "TWL4030/6030 PWM support"
+	depends on TWL4030_CORE
+	help
+	  Generic PWM framework driver for TWL4030/6030.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-twl.
+
+config PWM_TWL_LED
+	tristate "TWL4030/6030 PWM support for LED drivers"
+	depends on TWL4030_CORE
+	help
+	  Generic PWM framework driver for TWL4030/6030 LED terminals.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-twl-led.
+
+config PWM_VT8500
+	tristate "vt8500 PWM support"
+	depends on ARCH_VT8500
+	help
+	  Generic PWM framework driver for vt8500.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-vt8500.
+
+endif

drivers/pwm/Makefile

@@ -0,0 +1,19 @@
+obj-$(CONFIG_PWM)		+= core.o
+obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o
+obj-$(CONFIG_PWM_ATMEL_TCB)	+= pwm-atmel-tcb.o
+obj-$(CONFIG_PWM_BFIN)		+= pwm-bfin.o
+obj-$(CONFIG_PWM_IMX)		+= pwm-imx.o
+obj-$(CONFIG_PWM_JZ4740)	+= pwm-jz4740.o
+obj-$(CONFIG_PWM_LPC32XX)	+= pwm-lpc32xx.o
+obj-$(CONFIG_PWM_MXS)		+= pwm-mxs.o
+obj-$(CONFIG_PWM_PUV3)		+= pwm-puv3.o
+obj-$(CONFIG_PWM_PXA)		+= pwm-pxa.o
+obj-$(CONFIG_PWM_SAMSUNG)	+= pwm-samsung.o
+obj-$(CONFIG_PWM_SPEAR)		+= pwm-spear.o
+obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o
+obj-$(CONFIG_PWM_TIECAP)	+= pwm-tiecap.o
+obj-$(CONFIG_PWM_TIEHRPWM)	+= pwm-tiehrpwm.o
+obj-$(CONFIG_PWM_TIPWMSS)	+= pwm-tipwmss.o
+obj-$(CONFIG_PWM_TWL)		+= pwm-twl.o
+obj-$(CONFIG_PWM_TWL_LED)	+= pwm-twl-led.o
+obj-$(CONFIG_PWM_VT8500)	+= pwm-vt8500.o

drivers/pwm/core.c

@@ -0,0 +1,866 @@
+/*
+ * Generic pwmlib implementation
+ *
+ * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de>
+ * Copyright (C) 2011-2012 Avionic Design GmbH
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; see the file COPYING.  If not, write to
+ *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/pwm.h>
+#include <linux/radix-tree.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#define MAX_PWMS 1024
+
+/* flags in the third cell of the DT PWM specifier */
+#define PWM_SPEC_POLARITY	(1 << 0)
+
+static DEFINE_MUTEX(pwm_lookup_lock);
+static LIST_HEAD(pwm_lookup_list);
+static DEFINE_MUTEX(pwm_lock);
+static LIST_HEAD(pwm_chips);
+static DECLARE_BITMAP(allocated_pwms, MAX_PWMS);
+static RADIX_TREE(pwm_tree, GFP_KERNEL);
+
+static struct pwm_device *pwm_to_device(unsigned int pwm)
+{
+	return radix_tree_lookup(&pwm_tree, pwm);
+}
+
+static int alloc_pwms(int pwm, unsigned int count)
+{
+	unsigned int from = 0;
+	unsigned int start;
+
+	if (pwm >= MAX_PWMS)
+		return -EINVAL;
+
+	if (pwm >= 0)
+		from = pwm;
+
+	start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, from,
+					   count, 0);
+
+	if (pwm >= 0 && start != pwm)
+		return -EEXIST;
+
+	if (start + count > MAX_PWMS)
+		return -ENOSPC;
+
+	return start;
+}
+
+static void free_pwms(struct pwm_chip *chip)
+{
+	unsigned int i;
+
+	for (i = 0; i < chip->npwm; i++) {
+		struct pwm_device *pwm = &chip->pwms[i];
+		radix_tree_delete(&pwm_tree, pwm->pwm);
+	}
+
+	bitmap_clear(allocated_pwms, chip->base, chip->npwm);
+
+	kfree(chip->pwms);
+	chip->pwms = NULL;
+}
+
+static struct pwm_chip *pwmchip_find_by_name(const char *name)
+{
+	struct pwm_chip *chip;
+
+	if (!name)
+		return NULL;
+
+	mutex_lock(&pwm_lock);
+
+	list_for_each_entry(chip, &pwm_chips, list) {
+		const char *chip_name = dev_name(chip->dev);
+
+		if (chip_name && strcmp(chip_name, name) == 0) {
+			mutex_unlock(&pwm_lock);
+			return chip;
+		}
+	}
+
+	mutex_unlock(&pwm_lock);
+
+	return NULL;
+}
+
+static int pwm_device_request(struct pwm_device *pwm, const char *label)
+{
+	int err;
+
+	if (test_bit(PWMF_REQUESTED, &pwm->flags))
+		return -EBUSY;
+
+	if (!try_module_get(pwm->chip->ops->owner))
+		return -ENODEV;
+
+	if (pwm->chip->ops->request) {
+		err = pwm->chip->ops->request(pwm->chip, pwm);
+		if (err) {
+			module_put(pwm->chip->ops->owner);
+			return err;
+		}
+	}
+
+	set_bit(PWMF_REQUESTED, &pwm->flags);
+	pwm->label = label;
+
+	return 0;
+}
+
+struct pwm_device *
+of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
+{
+	struct pwm_device *pwm;
+
+	if (pc->of_pwm_n_cells < 3)
+		return ERR_PTR(-EINVAL);
+
+	if (args->args[0] >= pc->npwm)
+		return ERR_PTR(-EINVAL);
+
+	pwm = pwm_request_from_chip(pc, args->args[0], NULL);
+	if (IS_ERR(pwm))
+		return pwm;
+
+	pwm_set_period(pwm, args->args[1]);
+
+	if (args->args[2] & PWM_SPEC_POLARITY)
+		pwm_set_polarity(pwm, PWM_POLARITY_INVERSED);
+	else
+		pwm_set_polarity(pwm, PWM_POLARITY_NORMAL);
+
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags);
+
+static struct pwm_device *
+of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
+{
+	struct pwm_device *pwm;
+
+	if (pc->of_pwm_n_cells < 2)
+		return ERR_PTR(-EINVAL);
+
+	if (args->args[0] >= pc->npwm)
+		return ERR_PTR(-EINVAL);
+
+	pwm = pwm_request_from_chip(pc, args->args[0], NULL);
+	if (IS_ERR(pwm))
+		return pwm;
+
+	pwm_set_period(pwm, args->args[1]);
+
+	return pwm;
+}
+
+static void of_pwmchip_add(struct pwm_chip *chip)
+{
+	if (!chip->dev || !chip->dev->of_node)
+		return;
+
+	if (!chip->of_xlate) {
+		chip->of_xlate = of_pwm_simple_xlate;
+		chip->of_pwm_n_cells = 2;
+	}
+
+	of_node_get(chip->dev->of_node);
+}
+
+static void of_pwmchip_remove(struct pwm_chip *chip)
+{
+	if (chip->dev && chip->dev->of_node)
+		of_node_put(chip->dev->of_node);
+}
+
+/**
+ * pwm_set_chip_data() - set private chip data for a PWM
+ * @pwm: PWM device
+ * @data: pointer to chip-specific data
+ */
+int pwm_set_chip_data(struct pwm_device *pwm, void *data)
+{
+	if (!pwm)
+		return -EINVAL;
+
+	pwm->chip_data = data;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pwm_set_chip_data);
+
+/**
+ * pwm_get_chip_data() - get private chip data for a PWM
+ * @pwm: PWM device
+ */
+void *pwm_get_chip_data(struct pwm_device *pwm)
+{
+	return pwm ? pwm->chip_data : NULL;
+}
+EXPORT_SYMBOL_GPL(pwm_get_chip_data);
+
+/**
+ * pwmchip_add() - register a new PWM chip
+ * @chip: the PWM chip to add
+ *
+ * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
+ * will be used.
+ */
+int pwmchip_add(struct pwm_chip *chip)
+{
+	struct pwm_device *pwm;
+	unsigned int i;
+	int ret;
+
+	if (!chip || !chip->dev || !chip->ops || !chip->ops->config ||
+	    !chip->ops->enable || !chip->ops->disable)
+		return -EINVAL;
+
+	mutex_lock(&pwm_lock);
+
+	ret = alloc_pwms(chip->base, chip->npwm);
+	if (ret < 0)
+		goto out;
+
+	chip->pwms = kzalloc(chip->npwm * sizeof(*pwm), GFP_KERNEL);
+	if (!chip->pwms) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	chip->base = ret;
+
+	for (i = 0; i < chip->npwm; i++) {
+		pwm = &chip->pwms[i];
+
+		pwm->chip = chip;
+		pwm->pwm = chip->base + i;
+		pwm->hwpwm = i;
+
+		radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
+	}
+
+	bitmap_set(allocated_pwms, chip->base, chip->npwm);
+
+	INIT_LIST_HEAD(&chip->list);
+	list_add(&chip->list, &pwm_chips);
+
+	ret = 0;
+
+	if (IS_ENABLED(CONFIG_OF))
+		of_pwmchip_add(chip);
+
+out:
+	mutex_unlock(&pwm_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pwmchip_add);
+
+/**
+ * pwmchip_remove() - remove a PWM chip
+ * @chip: the PWM chip to remove
+ *
+ * Removes a PWM chip. This function may return busy if the PWM chip provides
+ * a PWM device that is still requested.
+ */
+int pwmchip_remove(struct pwm_chip *chip)
+{
+	unsigned int i;
+	int ret = 0;
+
+	mutex_lock(&pwm_lock);
+
+	for (i = 0; i < chip->npwm; i++) {
+		struct pwm_device *pwm = &chip->pwms[i];
+
+		if (test_bit(PWMF_REQUESTED, &pwm->flags)) {
+			ret = -EBUSY;
+			goto out;
+		}
+	}
+
+	list_del_init(&chip->list);
+
+	if (IS_ENABLED(CONFIG_OF))
+		of_pwmchip_remove(chip);
+
+	free_pwms(chip);
+
+out:
+	mutex_unlock(&pwm_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pwmchip_remove);
+
+/**
+ * pwm_request() - request a PWM device
+ * @pwm_id: global PWM device index
+ * @label: PWM device label
+ *
+ * This function is deprecated, use pwm_get() instead.
+ */
+struct pwm_device *pwm_request(int pwm, const char *label)
+{
+	struct pwm_device *dev;
+	int err;
+
+	if (pwm < 0 || pwm >= MAX_PWMS)
+		return ERR_PTR(-EINVAL);
+
+	mutex_lock(&pwm_lock);
+
+	dev = pwm_to_device(pwm);
+	if (!dev) {
+		dev = ERR_PTR(-EPROBE_DEFER);
+		goto out;
+	}
+
+	err = pwm_device_request(dev, label);
+	if (err < 0)
+		dev = ERR_PTR(err);
+
+out:
+	mutex_unlock(&pwm_lock);
+
+	return dev;
+}
+EXPORT_SYMBOL_GPL(pwm_request);
+
+/**
+ * pwm_request_from_chip() - request a PWM device relative to a PWM chip
+ * @chip: PWM chip
+ * @index: per-chip index of the PWM to request
+ * @label: a literal description string of this PWM
+ *
+ * Returns the PWM at the given index of the given PWM chip. A negative error
+ * code is returned if the index is not valid for the specified PWM chip or
+ * if the PWM device cannot be requested.
+ */
+struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
+					 unsigned int index,
+					 const char *label)
+{
+	struct pwm_device *pwm;
+	int err;
+
+	if (!chip || index >= chip->npwm)
+		return ERR_PTR(-EINVAL);
+
+	mutex_lock(&pwm_lock);
+	pwm = &chip->pwms[index];
+
+	err = pwm_device_request(pwm, label);
+	if (err < 0)
+		pwm = ERR_PTR(err);
+
+	mutex_unlock(&pwm_lock);
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(pwm_request_from_chip);
+
+/**
+ * pwm_free() - free a PWM device
+ * @pwm: PWM device
+ *
+ * This function is deprecated, use pwm_put() instead.
+ */
+void pwm_free(struct pwm_device *pwm)
+{
+	pwm_put(pwm);
+}
+EXPORT_SYMBOL_GPL(pwm_free);
+
+/**
+ * pwm_config() - change a PWM device configuration
+ * @pwm: PWM device
+ * @duty_ns: "on" time (in nanoseconds)
+ * @period_ns: duration (in nanoseconds) of one cycle
+ */
+int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	if (!pwm || duty_ns < 0 || period_ns <= 0 || duty_ns > period_ns)
+		return -EINVAL;
+
+	return pwm->chip->ops->config(pwm->chip, pwm, duty_ns, period_ns);
+}
+EXPORT_SYMBOL_GPL(pwm_config);
+
+/**
+ * pwm_set_polarity() - configure the polarity of a PWM signal
+ * @pwm: PWM device
+ * @polarity: new polarity of the PWM signal
+ *
+ * Note that the polarity cannot be configured while the PWM device is enabled
+ */
+int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
+{
+	if (!pwm || !pwm->chip->ops)
+		return -EINVAL;
+
+	if (!pwm->chip->ops->set_polarity)
+		return -ENOSYS;
+
+	if (test_bit(PWMF_ENABLED, &pwm->flags))
+		return -EBUSY;
+
+	return pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
+}
+EXPORT_SYMBOL_GPL(pwm_set_polarity);
+
+/**
+ * pwm_enable() - start a PWM output toggling
+ * @pwm: PWM device
+ */
+int pwm_enable(struct pwm_device *pwm)
+{
+	if (pwm && !test_and_set_bit(PWMF_ENABLED, &pwm->flags))
+		return pwm->chip->ops->enable(pwm->chip, pwm);
+
+	return pwm ? 0 : -EINVAL;
+}
+EXPORT_SYMBOL_GPL(pwm_enable);
+
+/**
+ * pwm_disable() - stop a PWM output toggling
+ * @pwm: PWM device
+ */
+void pwm_disable(struct pwm_device *pwm)
+{
+	if (pwm && test_and_clear_bit(PWMF_ENABLED, &pwm->flags))
+		pwm->chip->ops->disable(pwm->chip, pwm);
+}
+EXPORT_SYMBOL_GPL(pwm_disable);
+
+static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
+{
+	struct pwm_chip *chip;
+
+	mutex_lock(&pwm_lock);
+
+	list_for_each_entry(chip, &pwm_chips, list)
+		if (chip->dev && chip->dev->of_node == np) {
+			mutex_unlock(&pwm_lock);
+			return chip;
+		}
+
+	mutex_unlock(&pwm_lock);
+
+	return ERR_PTR(-EPROBE_DEFER);
+}
+
+/**
+ * of_pwm_get() - request a PWM via the PWM framework
+ * @np: device node to get the PWM from
+ * @con_id: consumer name
+ *
+ * Returns the PWM device parsed from the phandle and index specified in the
+ * "pwms" property of a device tree node or a negative error-code on failure.
+ * Values parsed from the device tree are stored in the returned PWM device
+ * object.
+ *
+ * If con_id is NULL, the first PWM device listed in the "pwms" property will
+ * be requested. Otherwise the "pwm-names" property is used to do a reverse
+ * lookup of the PWM index. This also means that the "pwm-names" property
+ * becomes mandatory for devices that look up the PWM device via the con_id
+ * parameter.
+ */
+struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
+{
+	struct pwm_device *pwm = NULL;
+	struct of_phandle_args args;
+	struct pwm_chip *pc;
+	int index = 0;
+	int err;
+
+	if (con_id) {
+		index = of_property_match_string(np, "pwm-names", con_id);
+		if (index < 0)
+			return ERR_PTR(index);
+	}
+
+	err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index,
+					 &args);
+	if (err) {
+		pr_debug("%s(): can't parse \"pwms\" property\n", __func__);
+		return ERR_PTR(err);
+	}
+
+	pc = of_node_to_pwmchip(args.np);
+	if (IS_ERR(pc)) {
+		pr_debug("%s(): PWM chip not found\n", __func__);
+		pwm = ERR_CAST(pc);
+		goto put;
+	}
+
+	if (args.args_count != pc->of_pwm_n_cells) {
+		pr_debug("%s: wrong #pwm-cells for %s\n", np->full_name,
+			 args.np->full_name);
+		pwm = ERR_PTR(-EINVAL);
+		goto put;
+	}
+
+	pwm = pc->of_xlate(pc, &args);
+	if (IS_ERR(pwm))
+		goto put;
+
+	/*
+	 * If a consumer name was not given, try to look it up from the
+	 * "pwm-names" property if it exists. Otherwise use the name of
+	 * the user device node.
+	 */
+	if (!con_id) {
+		err = of_property_read_string_index(np, "pwm-names", index,
+						    &con_id);
+		if (err < 0)
+			con_id = np->name;
+	}
+
+	pwm->label = con_id;
+
+put:
+	of_node_put(args.np);
+
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(of_pwm_get);
+
+/**
+ * pwm_add_table() - register PWM device consumers
+ * @table: array of consumers to register
+ * @num: number of consumers in table
+ */
+void __init pwm_add_table(struct pwm_lookup *table, size_t num)
+{
+	mutex_lock(&pwm_lookup_lock);
+
+	while (num--) {
+		list_add_tail(&table->list, &pwm_lookup_list);
+		table++;
+	}
+
+	mutex_unlock(&pwm_lookup_lock);
+}
+
+/**
+ * pwm_get() - look up and request a PWM device
+ * @dev: device for PWM consumer
+ * @con_id: consumer name
+ *
+ * Lookup is first attempted using DT. If the device was not instantiated from
+ * a device tree, a PWM chip and a relative index is looked up via a table
+ * supplied by board setup code (see pwm_add_table()).
+ *
+ * Once a PWM chip has been found the specified PWM device will be requested
+ * and is ready to be used.
+ */
+struct pwm_device *pwm_get(struct device *dev, const char *con_id)
+{
+	struct pwm_device *pwm = ERR_PTR(-EPROBE_DEFER);
+	const char *dev_id = dev ? dev_name(dev) : NULL;
+	struct pwm_chip *chip = NULL;
+	unsigned int index = 0;
+	unsigned int best = 0;
+	struct pwm_lookup *p;
+	unsigned int match;
+
+	/* look up via DT first */
+	if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
+		return of_pwm_get(dev->of_node, con_id);
+
+	/*
+	 * We look up the provider in the static table typically provided by
+	 * board setup code. We first try to lookup the consumer device by
+	 * name. If the consumer device was passed in as NULL or if no match
+	 * was found, we try to find the consumer by directly looking it up
+	 * by name.
+	 *
+	 * If a match is found, the provider PWM chip is looked up by name
+	 * and a PWM device is requested using the PWM device per-chip index.
+	 *
+	 * The lookup algorithm was shamelessly taken from the clock
+	 * framework:
+	 *
+	 * We do slightly fuzzy matching here:
+	 *  An entry with a NULL ID is assumed to be a wildcard.
+	 *  If an entry has a device ID, it must match
+	 *  If an entry has a connection ID, it must match
+	 * Then we take the most specific entry - with the following order
+	 * of precedence: dev+con > dev only > con only.
+	 */
+	mutex_lock(&pwm_lookup_lock);
+
+	list_for_each_entry(p, &pwm_lookup_list, list) {
+		match = 0;
+
+		if (p->dev_id) {
+			if (!dev_id || strcmp(p->dev_id, dev_id))
+				continue;
+
+			match += 2;
+		}
+
+		if (p->con_id) {
+			if (!con_id || strcmp(p->con_id, con_id))
+				continue;
+
+			match += 1;
+		}
+
+		if (match > best) {
+			chip = pwmchip_find_by_name(p->provider);
+			index = p->index;
+
+			if (match != 3)
+				best = match;
+			else
+				break;
+		}
+	}
+
+	if (chip)
+		pwm = pwm_request_from_chip(chip, index, con_id ?: dev_id);
+
+	mutex_unlock(&pwm_lookup_lock);
+
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(pwm_get);
+
+/**
+ * pwm_put() - release a PWM device
+ * @pwm: PWM device
+ */
+void pwm_put(struct pwm_device *pwm)
+{
+	if (!pwm)
+		return;
+
+	mutex_lock(&pwm_lock);
+
+	if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) {
+		pr_warn("PWM device already freed\n");
+		goto out;
+	}
+
+	if (pwm->chip->ops->free)
+		pwm->chip->ops->free(pwm->chip, pwm);
+
+	pwm->label = NULL;
+
+	module_put(pwm->chip->ops->owner);
+out:
+	mutex_unlock(&pwm_lock);
+}
+EXPORT_SYMBOL_GPL(pwm_put);
+
+static void devm_pwm_release(struct device *dev, void *res)
+{
+	pwm_put(*(struct pwm_device **)res);
+}
+
+/**
+ * devm_pwm_get() - resource managed pwm_get()
+ * @dev: device for PWM consumer
+ * @con_id: consumer name
+ *
+ * This function performs like pwm_get() but the acquired PWM device will
+ * automatically be released on driver detach.
+ */
+struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id)
+{
+	struct pwm_device **ptr, *pwm;
+
+	ptr = devres_alloc(devm_pwm_release, sizeof(**ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	pwm = pwm_get(dev, con_id);
+	if (!IS_ERR(pwm)) {
+		*ptr = pwm;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_pwm_get);
+
+/**
+ * devm_of_pwm_get() - resource managed of_pwm_get()
+ * @dev: device for PWM consumer
+ * @np: device node to get the PWM from
+ * @con_id: consumer name
+ *
+ * This function performs like of_pwm_get() but the acquired PWM device will
+ * automatically be released on driver detach.
+ */
+struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
+				   const char *con_id)
+{
+	struct pwm_device **ptr, *pwm;
+
+	ptr = devres_alloc(devm_pwm_release, sizeof(**ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	pwm = of_pwm_get(np, con_id);
+	if (!IS_ERR(pwm)) {
+		*ptr = pwm;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_of_pwm_get);
+
+static int devm_pwm_match(struct device *dev, void *res, void *data)
+{
+	struct pwm_device **p = res;
+
+	if (WARN_ON(!p || !*p))
+		return 0;
+
+	return *p == data;
+}
+
+/**
+ * devm_pwm_put() - resource managed pwm_put()
+ * @dev: device for PWM consumer
+ * @pwm: PWM device
+ *
+ * Release a PWM previously allocated using devm_pwm_get(). Calling this
+ * function is usually not needed because devm-allocated resources are
+ * automatically released on driver detach.
+ */
+void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
+{
+	WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm));
+}
+EXPORT_SYMBOL_GPL(devm_pwm_put);
+
+/**
+  * pwm_can_sleep() - report whether PWM access will sleep
+  * @pwm: PWM device
+  *
+  * It returns true if accessing the PWM can sleep, false otherwise.
+  */
+bool pwm_can_sleep(struct pwm_device *pwm)
+{
+	return pwm->chip->can_sleep;
+}
+EXPORT_SYMBOL_GPL(pwm_can_sleep);
+
+#ifdef CONFIG_DEBUG_FS
+static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
+{
+	unsigned int i;
+
+	for (i = 0; i < chip->npwm; i++) {
+		struct pwm_device *pwm = &chip->pwms[i];
+
+		seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label);
+
+		if (test_bit(PWMF_REQUESTED, &pwm->flags))
+			seq_printf(s, " requested");
+
+		if (test_bit(PWMF_ENABLED, &pwm->flags))
+			seq_printf(s, " enabled");
+
+		seq_printf(s, "\n");
+	}
+}
+
+static void *pwm_seq_start(struct seq_file *s, loff_t *pos)
+{
+	mutex_lock(&pwm_lock);
+	s->private = "";
+
+	return seq_list_start(&pwm_chips, *pos);
+}
+
+static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+	s->private = "\n";
+
+	return seq_list_next(v, &pwm_chips, pos);
+}
+
+static void pwm_seq_stop(struct seq_file *s, void *v)
+{
+	mutex_unlock(&pwm_lock);
+}
+
+static int pwm_seq_show(struct seq_file *s, void *v)
+{
+	struct pwm_chip *chip = list_entry(v, struct pwm_chip, list);
+
+	seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private,
+		   chip->dev->bus ? chip->dev->bus->name : "no-bus",
+		   dev_name(chip->dev), chip->npwm,
+		   (chip->npwm != 1) ? "s" : "");
+
+	if (chip->ops->dbg_show)
+		chip->ops->dbg_show(chip, s);
+	else
+		pwm_dbg_show(chip, s);
+
+	return 0;
+}
+
+static const struct seq_operations pwm_seq_ops = {
+	.start = pwm_seq_start,
+	.next = pwm_seq_next,
+	.stop = pwm_seq_stop,
+	.show = pwm_seq_show,
+};
+
+static int pwm_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &pwm_seq_ops);
+}
+
+static const struct file_operations pwm_debugfs_ops = {
+	.owner = THIS_MODULE,
+	.open = pwm_seq_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release,
+};
+
+static int __init pwm_debugfs_init(void)
+{
+	debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL,
+			    &pwm_debugfs_ops);
+
+	return 0;
+}
+
+subsys_initcall(pwm_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */

drivers/pwm/pwm-ab8500.c

@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Author: Arun R Murthy <arun.murthy@stericsson.com>
+ * License terms: GNU General Public License (GPL) version 2
+ */
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pwm.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/module.h>
+
+/*
+ * PWM Out generators
+ * Bank: 0x10
+ */
+#define AB8500_PWM_OUT_CTRL1_REG	0x60
+#define AB8500_PWM_OUT_CTRL2_REG	0x61
+#define AB8500_PWM_OUT_CTRL7_REG	0x66
+
+/* backlight driver constants */
+#define ENABLE_PWM			1
+#define DISABLE_PWM			0
+
+struct ab8500_pwm_chip {
+	struct pwm_chip chip;
+};
+
+static int ab8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			     int duty_ns, int period_ns)
+{
+	int ret = 0;
+	unsigned int higher_val, lower_val;
+	u8 reg;
+
+	/*
+	 * get the first 8 bits that are be written to
+	 * AB8500_PWM_OUT_CTRL1_REG[0:7]
+	 */
+	lower_val = duty_ns & 0x00FF;
+	/*
+	 * get bits [9:10] that are to be written to
+	 * AB8500_PWM_OUT_CTRL2_REG[0:1]
+	 */
+	higher_val = ((duty_ns & 0x0300) >> 8);
+
+	reg = AB8500_PWM_OUT_CTRL1_REG + ((chip->base - 1) * 2);
+
+	ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
+			reg, (u8)lower_val);
+	if (ret < 0)
+		return ret;
+	ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
+			(reg + 1), (u8)higher_val);
+
+	return ret;
+}
+
+static int ab8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	int ret;
+
+	ret = abx500_mask_and_set_register_interruptible(chip->dev,
+				AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+				1 << (chip->base - 1), ENABLE_PWM);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
+							pwm->label, ret);
+	return ret;
+}
+
+static void ab8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	int ret;
+
+	ret = abx500_mask_and_set_register_interruptible(chip->dev,
+				AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+				1 << (chip->base - 1), DISABLE_PWM);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
+							pwm->label, ret);
+	return;
+}
+
+static const struct pwm_ops ab8500_pwm_ops = {
+	.config = ab8500_pwm_config,
+	.enable = ab8500_pwm_enable,
+	.disable = ab8500_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int ab8500_pwm_probe(struct platform_device *pdev)
+{
+	struct ab8500_pwm_chip *ab8500;
+	int err;
+
+	/*
+	 * Nothing to be done in probe, this is required to get the
+	 * device which is required for ab8500 read and write
+	 */
+	ab8500 = devm_kzalloc(&pdev->dev, sizeof(*ab8500), GFP_KERNEL);
+	if (ab8500 == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	ab8500->chip.dev = &pdev->dev;
+	ab8500->chip.ops = &ab8500_pwm_ops;
+	ab8500->chip.base = pdev->id;
+	ab8500->chip.npwm = 1;
+
+	err = pwmchip_add(&ab8500->chip);
+	if (err < 0)
+		return err;
+
+	dev_dbg(&pdev->dev, "pwm probe successful\n");
+	platform_set_drvdata(pdev, ab8500);
+
+	return 0;
+}
+
+static int ab8500_pwm_remove(struct platform_device *pdev)
+{
+	struct ab8500_pwm_chip *ab8500 = platform_get_drvdata(pdev);
+	int err;
+
+	err = pwmchip_remove(&ab8500->chip);
+	if (err < 0)
+		return err;
+
+	dev_dbg(&pdev->dev, "pwm driver removed\n");
+
+	return 0;
+}
+
+static struct platform_driver ab8500_pwm_driver = {
+	.driver = {
+		.name = "ab8500-pwm",
+		.owner = THIS_MODULE,
+	},
+	.probe = ab8500_pwm_probe,
+	.remove = ab8500_pwm_remove,
+};
+module_platform_driver(ab8500_pwm_driver);
+
+MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
+MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
+MODULE_ALIAS("platform:ab8500-pwm");
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-atmel-tcb.c

@@ -0,0 +1,446 @@
+/*
+ * Copyright (C) Overkiz SAS 2012
+ *
+ * Author: Boris BREZILLON <b.brezillon@overkiz.com>
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/atmel_tc.h>
+#include <linux/pwm.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+
+#define NPWM	6
+
+#define ATMEL_TC_ACMR_MASK	(ATMEL_TC_ACPA | ATMEL_TC_ACPC |	\
+				 ATMEL_TC_AEEVT | ATMEL_TC_ASWTRG)
+
+#define ATMEL_TC_BCMR_MASK	(ATMEL_TC_BCPB | ATMEL_TC_BCPC |	\
+				 ATMEL_TC_BEEVT | ATMEL_TC_BSWTRG)
+
+struct atmel_tcb_pwm_device {
+	enum pwm_polarity polarity;	/* PWM polarity */
+	unsigned div;			/* PWM clock divider */
+	unsigned duty;			/* PWM duty expressed in clk cycles */
+	unsigned period;		/* PWM period expressed in clk cycles */
+};
+
+struct atmel_tcb_pwm_chip {
+	struct pwm_chip chip;
+	spinlock_t lock;
+	struct atmel_tc *tc;
+	struct atmel_tcb_pwm_device *pwms[NPWM];
+};
+
+static inline struct atmel_tcb_pwm_chip *to_tcb_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct atmel_tcb_pwm_chip, chip);
+}
+
+static int atmel_tcb_pwm_set_polarity(struct pwm_chip *chip,
+				      struct pwm_device *pwm,
+				      enum pwm_polarity polarity)
+{
+	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
+
+	tcbpwm->polarity = polarity;
+
+	return 0;
+}
+
+static int atmel_tcb_pwm_request(struct pwm_chip *chip,
+				 struct pwm_device *pwm)
+{
+	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
+	struct atmel_tcb_pwm_device *tcbpwm;
+	struct atmel_tc *tc = tcbpwmc->tc;
+	void __iomem *regs = tc->regs;
+	unsigned group = pwm->hwpwm / 2;
+	unsigned index = pwm->hwpwm % 2;
+	unsigned cmr;
+	int ret;
+
+	tcbpwm = devm_kzalloc(chip->dev, sizeof(*tcbpwm), GFP_KERNEL);
+	if (!tcbpwm)
+		return -ENOMEM;
+
+	ret = clk_enable(tc->clk[group]);
+	if (ret) {
+		devm_kfree(chip->dev, tcbpwm);
+		return ret;
+	}
+
+	pwm_set_chip_data(pwm, tcbpwm);
+	tcbpwm->polarity = PWM_POLARITY_NORMAL;
+	tcbpwm->duty = 0;
+	tcbpwm->period = 0;
+	tcbpwm->div = 0;
+
+	spin_lock(&tcbpwmc->lock);
+	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+	/*
+	 * Get init config from Timer Counter registers if
+	 * Timer Counter is already configured as a PWM generator.
+	 */
+	if (cmr & ATMEL_TC_WAVE) {
+		if (index == 0)
+			tcbpwm->duty =
+				__raw_readl(regs + ATMEL_TC_REG(group, RA));
+		else
+			tcbpwm->duty =
+				__raw_readl(regs + ATMEL_TC_REG(group, RB));
+
+		tcbpwm->div = cmr & ATMEL_TC_TCCLKS;
+		tcbpwm->period = __raw_readl(regs + ATMEL_TC_REG(group, RC));
+		cmr &= (ATMEL_TC_TCCLKS | ATMEL_TC_ACMR_MASK |
+			ATMEL_TC_BCMR_MASK);
+	} else
+		cmr = 0;
+
+	cmr |= ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO | ATMEL_TC_EEVT_XC0;
+	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+	spin_unlock(&tcbpwmc->lock);
+
+	tcbpwmc->pwms[pwm->hwpwm] = tcbpwm;
+
+	return 0;
+}
+
+static void atmel_tcb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
+	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
+	struct atmel_tc *tc = tcbpwmc->tc;
+
+	clk_disable(tc->clk[pwm->hwpwm / 2]);
+	tcbpwmc->pwms[pwm->hwpwm] = NULL;
+	devm_kfree(chip->dev, tcbpwm);
+}
+
+static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
+	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
+	struct atmel_tc *tc = tcbpwmc->tc;
+	void __iomem *regs = tc->regs;
+	unsigned group = pwm->hwpwm / 2;
+	unsigned index = pwm->hwpwm % 2;
+	unsigned cmr;
+	enum pwm_polarity polarity = tcbpwm->polarity;
+
+	/*
+	 * If duty is 0 the timer will be stopped and we have to
+	 * configure the output correctly on software trigger:
+	 *  - set output to high if PWM_POLARITY_INVERSED
+	 *  - set output to low if PWM_POLARITY_NORMAL
+	 *
+	 * This is why we're reverting polarity in this case.
+	 */
+	if (tcbpwm->duty == 0)
+		polarity = !polarity;
+
+	spin_lock(&tcbpwmc->lock);
+	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+
+	/* flush old setting and set the new one */
+	if (index == 0) {
+		cmr &= ~ATMEL_TC_ACMR_MASK;
+		if (polarity == PWM_POLARITY_INVERSED)
+			cmr |= ATMEL_TC_ASWTRG_CLEAR;
+		else
+			cmr |= ATMEL_TC_ASWTRG_SET;
+	} else {
+		cmr &= ~ATMEL_TC_BCMR_MASK;
+		if (polarity == PWM_POLARITY_INVERSED)
+			cmr |= ATMEL_TC_BSWTRG_CLEAR;
+		else
+			cmr |= ATMEL_TC_BSWTRG_SET;
+	}
+
+	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+
+	/*
+	 * Use software trigger to apply the new setting.
+	 * If both PWM devices in this group are disabled we stop the clock.
+	 */
+	if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC)))
+		__raw_writel(ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS,
+			     regs + ATMEL_TC_REG(group, CCR));
+	else
+		__raw_writel(ATMEL_TC_SWTRG, regs +
+			     ATMEL_TC_REG(group, CCR));
+
+	spin_unlock(&tcbpwmc->lock);
+}
+
+static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
+	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
+	struct atmel_tc *tc = tcbpwmc->tc;
+	void __iomem *regs = tc->regs;
+	unsigned group = pwm->hwpwm / 2;
+	unsigned index = pwm->hwpwm % 2;
+	u32 cmr;
+	enum pwm_polarity polarity = tcbpwm->polarity;
+
+	/*
+	 * If duty is 0 the timer will be stopped and we have to
+	 * configure the output correctly on software trigger:
+	 *  - set output to high if PWM_POLARITY_INVERSED
+	 *  - set output to low if PWM_POLARITY_NORMAL
+	 *
+	 * This is why we're reverting polarity in this case.
+	 */
+	if (tcbpwm->duty == 0)
+		polarity = !polarity;
+
+	spin_lock(&tcbpwmc->lock);
+	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+
+	/* flush old setting and set the new one */
+	cmr &= ~ATMEL_TC_TCCLKS;
+
+	if (index == 0) {
+		cmr &= ~ATMEL_TC_ACMR_MASK;
+
+		/* Set CMR flags according to given polarity */
+		if (polarity == PWM_POLARITY_INVERSED)
+			cmr |= ATMEL_TC_ASWTRG_CLEAR;
+		else
+			cmr |= ATMEL_TC_ASWTRG_SET;
+	} else {
+		cmr &= ~ATMEL_TC_BCMR_MASK;
+		if (polarity == PWM_POLARITY_INVERSED)
+			cmr |= ATMEL_TC_BSWTRG_CLEAR;
+		else
+			cmr |= ATMEL_TC_BSWTRG_SET;
+	}
+
+	/*
+	 * If duty is 0 or equal to period there's no need to register
+	 * a specific action on RA/RB and RC compare.
+	 * The output will be configured on software trigger and keep
+	 * this config till next config call.
+	 */
+	if (tcbpwm->duty != tcbpwm->period && tcbpwm->duty > 0) {
+		if (index == 0) {
+			if (polarity == PWM_POLARITY_INVERSED)
+				cmr |= ATMEL_TC_ACPA_SET | ATMEL_TC_ACPC_CLEAR;
+			else
+				cmr |= ATMEL_TC_ACPA_CLEAR | ATMEL_TC_ACPC_SET;
+		} else {
+			if (polarity == PWM_POLARITY_INVERSED)
+				cmr |= ATMEL_TC_BCPB_SET | ATMEL_TC_BCPC_CLEAR;
+			else
+				cmr |= ATMEL_TC_BCPB_CLEAR | ATMEL_TC_BCPC_SET;
+		}
+	}
+
+	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+
+	if (index == 0)
+		__raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RA));
+	else
+		__raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RB));
+
+	__raw_writel(tcbpwm->period, regs + ATMEL_TC_REG(group, RC));
+
+	/* Use software trigger to apply the new setting */
+	__raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
+		     regs + ATMEL_TC_REG(group, CCR));
+	spin_unlock(&tcbpwmc->lock);
+	return 0;
+}
+
+static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+				int duty_ns, int period_ns)
+{
+	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
+	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
+	unsigned group = pwm->hwpwm / 2;
+	unsigned index = pwm->hwpwm % 2;
+	struct atmel_tcb_pwm_device *atcbpwm = NULL;
+	struct atmel_tc *tc = tcbpwmc->tc;
+	int i;
+	int slowclk = 0;
+	unsigned period;
+	unsigned duty;
+	unsigned rate = clk_get_rate(tc->clk[group]);
+	unsigned long long min;
+	unsigned long long max;
+
+	/*
+	 * Find best clk divisor:
+	 * the smallest divisor which can fulfill the period_ns requirements.
+	 */
+	for (i = 0; i < 5; ++i) {
+		if (atmel_tc_divisors[i] == 0) {
+			slowclk = i;
+			continue;
+		}
+		min = div_u64((u64)NSEC_PER_SEC * atmel_tc_divisors[i], rate);
+		max = min << tc->tcb_config->counter_width;
+		if (max >= period_ns)
+			break;
+	}
+
+	/*
+	 * If none of the divisor are small enough to represent period_ns
+	 * take slow clock (32KHz).
+	 */
+	if (i == 5) {
+		i = slowclk;
+		rate = 32768;
+		min = div_u64(NSEC_PER_SEC, rate);
+		max = min << 16;
+
+		/* If period is too big return ERANGE error */
+		if (max < period_ns)
+			return -ERANGE;
+	}
+
+	duty = div_u64(duty_ns, min);
+	period = div_u64(period_ns, min);
+
+	if (index == 0)
+		atcbpwm = tcbpwmc->pwms[pwm->hwpwm + 1];
+	else
+		atcbpwm = tcbpwmc->pwms[pwm->hwpwm - 1];
+
+	/*
+	 * PWM devices provided by TCB driver are grouped by 2:
+	 * - group 0: PWM 0 & 1
+	 * - group 1: PWM 2 & 3
+	 * - group 2: PWM 4 & 5
+	 *
+	 * PWM devices in a given group must be configured with the
+	 * same period_ns.
+	 *
+	 * We're checking the period value of the second PWM device
+	 * in this group before applying the new config.
+	 */
+	if ((atcbpwm && atcbpwm->duty > 0 &&
+			atcbpwm->duty != atcbpwm->period) &&
+		(atcbpwm->div != i || atcbpwm->period != period)) {
+		dev_err(chip->dev,
+			"failed to configure period_ns: PWM group already configured with a different value\n");
+		return -EINVAL;
+	}
+
+	tcbpwm->period = period;
+	tcbpwm->div = i;
+	tcbpwm->duty = duty;
+
+	/* If the PWM is enabled, call enable to apply the new conf */
+	if (test_bit(PWMF_ENABLED, &pwm->flags))
+		atmel_tcb_pwm_enable(chip, pwm);
+
+	return 0;
+}
+
+static const struct pwm_ops atmel_tcb_pwm_ops = {
+	.request = atmel_tcb_pwm_request,
+	.free = atmel_tcb_pwm_free,
+	.config = atmel_tcb_pwm_config,
+	.set_polarity = atmel_tcb_pwm_set_polarity,
+	.enable = atmel_tcb_pwm_enable,
+	.disable = atmel_tcb_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int atmel_tcb_pwm_probe(struct platform_device *pdev)
+{
+	struct atmel_tcb_pwm_chip *tcbpwm;
+	struct device_node *np = pdev->dev.of_node;
+	struct atmel_tc *tc;
+	int err;
+	int tcblock;
+
+	err = of_property_read_u32(np, "tc-block", &tcblock);
+	if (err < 0) {
+		dev_err(&pdev->dev,
+			"failed to get Timer Counter Block number from device tree (error: %d)\n",
+			err);
+		return err;
+	}
+
+	tc = atmel_tc_alloc(tcblock, "tcb-pwm");
+	if (tc == NULL) {
+		dev_err(&pdev->dev, "failed to allocate Timer Counter Block\n");
+		return -ENOMEM;
+	}
+
+	tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL);
+	if (tcbpwm == NULL) {
+		atmel_tc_free(tc);
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	tcbpwm->chip.dev = &pdev->dev;
+	tcbpwm->chip.ops = &atmel_tcb_pwm_ops;
+	tcbpwm->chip.of_xlate = of_pwm_xlate_with_flags;
+	tcbpwm->chip.of_pwm_n_cells = 3;
+	tcbpwm->chip.base = -1;
+	tcbpwm->chip.npwm = NPWM;
+	tcbpwm->tc = tc;
+
+	spin_lock_init(&tcbpwm->lock);
+
+	err = pwmchip_add(&tcbpwm->chip);
+	if (err < 0) {
+		atmel_tc_free(tc);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, tcbpwm);
+
+	return 0;
+}
+
+static int atmel_tcb_pwm_remove(struct platform_device *pdev)
+{
+	struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev);
+	int err;
+
+	err = pwmchip_remove(&tcbpwm->chip);
+	if (err < 0)
+		return err;
+
+	atmel_tc_free(tcbpwm->tc);
+
+	return 0;
+}
+
+static const struct of_device_id atmel_tcb_pwm_dt_ids[] = {
+	{ .compatible = "atmel,tcb-pwm", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, atmel_tcb_pwm_dt_ids);
+
+static struct platform_driver atmel_tcb_pwm_driver = {
+	.driver = {
+		.name = "atmel-tcb-pwm",
+		.of_match_table = atmel_tcb_pwm_dt_ids,
+	},
+	.probe = atmel_tcb_pwm_probe,
+	.remove = atmel_tcb_pwm_remove,
+};
+module_platform_driver(atmel_tcb_pwm_driver);
+
+MODULE_AUTHOR("Boris BREZILLON <b.brezillon@overkiz.com>");
+MODULE_DESCRIPTION("Atmel Timer Counter Pulse Width Modulation Driver");
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-bfin.c

@@ -0,0 +1,159 @@
+/*
+ * Blackfin Pulse Width Modulation (PWM) core
+ *
+ * Copyright (c) 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+#include <asm/gptimers.h>
+#include <asm/portmux.h>
+
+struct bfin_pwm_chip {
+	struct pwm_chip chip;
+};
+
+struct bfin_pwm {
+	unsigned short pin;
+};
+
+static const unsigned short pwm_to_gptimer_per[] = {
+	P_TMR0, P_TMR1, P_TMR2, P_TMR3, P_TMR4, P_TMR5,
+	P_TMR6, P_TMR7, P_TMR8, P_TMR9, P_TMR10, P_TMR11,
+};
+
+static int bfin_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bfin_pwm *priv;
+	int ret;
+
+	if (pwm->hwpwm >= ARRAY_SIZE(pwm_to_gptimer_per))
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->pin = pwm_to_gptimer_per[pwm->hwpwm];
+
+	ret = peripheral_request(priv->pin, NULL);
+	if (ret) {
+		kfree(priv);
+		return ret;
+	}
+
+	pwm_set_chip_data(pwm, priv);
+
+	return 0;
+}
+
+static void bfin_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bfin_pwm *priv = pwm_get_chip_data(pwm);
+
+	if (priv) {
+		peripheral_free(priv->pin);
+		kfree(priv);
+	}
+}
+
+static int bfin_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
+{
+	struct bfin_pwm *priv = pwm_get_chip_data(pwm);
+	unsigned long period, duty;
+	unsigned long long val;
+
+	val = (unsigned long long)get_sclk() * period_ns;
+	do_div(val, NSEC_PER_SEC);
+	period = val;
+
+	val = (unsigned long long)period * duty_ns;
+	do_div(val, period_ns);
+	duty = period - val;
+
+	if (duty >= period)
+		duty = period - 1;
+
+	set_gptimer_config(priv->pin, TIMER_MODE_PWM | TIMER_PERIOD_CNT);
+	set_gptimer_pwidth(priv->pin, duty);
+	set_gptimer_period(priv->pin, period);
+
+	return 0;
+}
+
+static int bfin_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bfin_pwm *priv = pwm_get_chip_data(pwm);
+
+	enable_gptimer(priv->pin);
+
+	return 0;
+}
+
+static void bfin_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bfin_pwm *priv = pwm_get_chip_data(pwm);
+
+	disable_gptimer(priv->pin);
+}
+
+static struct pwm_ops bfin_pwm_ops = {
+	.request = bfin_pwm_request,
+	.free = bfin_pwm_free,
+	.config = bfin_pwm_config,
+	.enable = bfin_pwm_enable,
+	.disable = bfin_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int bfin_pwm_probe(struct platform_device *pdev)
+{
+	struct bfin_pwm_chip *pwm;
+	int ret;
+
+	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+	if (!pwm) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, pwm);
+
+	pwm->chip.dev = &pdev->dev;
+	pwm->chip.ops = &bfin_pwm_ops;
+	pwm->chip.base = -1;
+	pwm->chip.npwm = 12;
+
+	ret = pwmchip_add(&pwm->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bfin_pwm_remove(struct platform_device *pdev)
+{
+	struct bfin_pwm_chip *pwm = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&pwm->chip);
+}
+
+static struct platform_driver bfin_pwm_driver = {
+	.driver = {
+		.name = "bfin-pwm",
+	},
+	.probe = bfin_pwm_probe,
+	.remove = bfin_pwm_remove,
+};
+
+module_platform_driver(bfin_pwm_driver);
+
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-imx.c

@@ -0,0 +1,307 @@
+/*
+ * simple driver for PWM (Pulse Width Modulator) controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Derived from pxa PWM driver by eric miao <eric.miao@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <linux/of_device.h>
+
+/* i.MX1 and i.MX21 share the same PWM function block: */
+
+#define MX1_PWMC    0x00   /* PWM Control Register */
+#define MX1_PWMS    0x04   /* PWM Sample Register */
+#define MX1_PWMP    0x08   /* PWM Period Register */
+
+#define MX1_PWMC_EN		(1 << 4)
+
+/* i.MX27, i.MX31, i.MX35 share the same PWM function block: */
+
+#define MX3_PWMCR                 0x00    /* PWM Control Register */
+#define MX3_PWMSAR                0x0C    /* PWM Sample Register */
+#define MX3_PWMPR                 0x10    /* PWM Period Register */
+#define MX3_PWMCR_PRESCALER(x)    (((x - 1) & 0xFFF) << 4)
+#define MX3_PWMCR_DOZEEN                (1 << 24)
+#define MX3_PWMCR_WAITEN                (1 << 23)
+#define MX3_PWMCR_DBGEN			(1 << 22)
+#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
+#define MX3_PWMCR_CLKSRC_IPG      (1 << 16)
+#define MX3_PWMCR_EN              (1 << 0)
+
+struct imx_chip {
+	struct clk	*clk_per;
+	struct clk	*clk_ipg;
+
+	void __iomem	*mmio_base;
+
+	struct pwm_chip	chip;
+
+	int (*config)(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns);
+	void (*set_enable)(struct pwm_chip *chip, bool enable);
+};
+
+#define to_imx_chip(chip)	container_of(chip, struct imx_chip, chip)
+
+static int imx_pwm_config_v1(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+
+	/*
+	 * The PWM subsystem allows for exact frequencies. However,
+	 * I cannot connect a scope on my device to the PWM line and
+	 * thus cannot provide the program the PWM controller
+	 * exactly. Instead, I'm relying on the fact that the
+	 * Bootloader (u-boot or WinCE+haret) has programmed the PWM
+	 * function group already. So I'll just modify the PWM sample
+	 * register to follow the ratio of duty_ns vs. period_ns
+	 * accordingly.
+	 *
+	 * This is good enough for programming the brightness of
+	 * the LCD backlight.
+	 *
+	 * The real implementation would divide PERCLK[0] first by
+	 * both the prescaler (/1 .. /128) and then by CLKSEL
+	 * (/2 .. /16).
+	 */
+	u32 max = readl(imx->mmio_base + MX1_PWMP);
+	u32 p = max * duty_ns / period_ns;
+	writel(max - p, imx->mmio_base + MX1_PWMS);
+
+	return 0;
+}
+
+static void imx_pwm_set_enable_v1(struct pwm_chip *chip, bool enable)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	u32 val;
+
+	val = readl(imx->mmio_base + MX1_PWMC);
+
+	if (enable)
+		val |= MX1_PWMC_EN;
+	else
+		val &= ~MX1_PWMC_EN;
+
+	writel(val, imx->mmio_base + MX1_PWMC);
+}
+
+static int imx_pwm_config_v2(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	unsigned long long c;
+	unsigned long period_cycles, duty_cycles, prescale;
+	u32 cr;
+
+	c = clk_get_rate(imx->clk_per);
+	c = c * period_ns;
+	do_div(c, 1000000000);
+	period_cycles = c;
+
+	prescale = period_cycles / 0x10000 + 1;
+
+	period_cycles /= prescale;
+	c = (unsigned long long)period_cycles * duty_ns;
+	do_div(c, period_ns);
+	duty_cycles = c;
+
+	/*
+	 * according to imx pwm RM, the real period value should be
+	 * PERIOD value in PWMPR plus 2.
+	 */
+	if (period_cycles > 2)
+		period_cycles -= 2;
+	else
+		period_cycles = 0;
+
+	writel(duty_cycles, imx->mmio_base + MX3_PWMSAR);
+	writel(period_cycles, imx->mmio_base + MX3_PWMPR);
+
+	cr = MX3_PWMCR_PRESCALER(prescale) |
+		MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN |
+		MX3_PWMCR_DBGEN | MX3_PWMCR_CLKSRC_IPG_HIGH;
+
+	if (test_bit(PWMF_ENABLED, &pwm->flags))
+		cr |= MX3_PWMCR_EN;
+
+	writel(cr, imx->mmio_base + MX3_PWMCR);
+
+	return 0;
+}
+
+static void imx_pwm_set_enable_v2(struct pwm_chip *chip, bool enable)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	u32 val;
+
+	val = readl(imx->mmio_base + MX3_PWMCR);
+
+	if (enable)
+		val |= MX3_PWMCR_EN;
+	else
+		val &= ~MX3_PWMCR_EN;
+
+	writel(val, imx->mmio_base + MX3_PWMCR);
+}
+
+static int imx_pwm_config(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	int ret;
+
+	ret = clk_prepare_enable(imx->clk_ipg);
+	if (ret)
+		return ret;
+
+	ret = imx->config(chip, pwm, duty_ns, period_ns);
+
+	clk_disable_unprepare(imx->clk_ipg);
+
+	return ret;
+}
+
+static int imx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	int ret;
+
+	ret = clk_prepare_enable(imx->clk_per);
+	if (ret)
+		return ret;
+
+	imx->set_enable(chip, true);
+
+	return 0;
+}
+
+static void imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+
+	imx->set_enable(chip, false);
+
+	clk_disable_unprepare(imx->clk_per);
+}
+
+static struct pwm_ops imx_pwm_ops = {
+	.enable = imx_pwm_enable,
+	.disable = imx_pwm_disable,
+	.config = imx_pwm_config,
+	.owner = THIS_MODULE,
+};
+
+struct imx_pwm_data {
+	int (*config)(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns);
+	void (*set_enable)(struct pwm_chip *chip, bool enable);
+};
+
+static struct imx_pwm_data imx_pwm_data_v1 = {
+	.config = imx_pwm_config_v1,
+	.set_enable = imx_pwm_set_enable_v1,
+};
+
+static struct imx_pwm_data imx_pwm_data_v2 = {
+	.config = imx_pwm_config_v2,
+	.set_enable = imx_pwm_set_enable_v2,
+};
+
+static const struct of_device_id imx_pwm_dt_ids[] = {
+	{ .compatible = "fsl,imx1-pwm", .data = &imx_pwm_data_v1, },
+	{ .compatible = "fsl,imx27-pwm", .data = &imx_pwm_data_v2, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_pwm_dt_ids);
+
+static int imx_pwm_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *of_id =
+			of_match_device(imx_pwm_dt_ids, &pdev->dev);
+	const struct imx_pwm_data *data;
+	struct imx_chip *imx;
+	struct resource *r;
+	int ret = 0;
+
+	if (!of_id)
+		return -ENODEV;
+
+	imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL);
+	if (imx == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	imx->clk_per = devm_clk_get(&pdev->dev, "per");
+	if (IS_ERR(imx->clk_per)) {
+		dev_err(&pdev->dev, "getting per clock failed with %ld\n",
+				PTR_ERR(imx->clk_per));
+		return PTR_ERR(imx->clk_per);
+	}
+
+	imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
+	if (IS_ERR(imx->clk_ipg)) {
+		dev_err(&pdev->dev, "getting ipg clock failed with %ld\n",
+				PTR_ERR(imx->clk_ipg));
+		return PTR_ERR(imx->clk_ipg);
+	}
+
+	imx->chip.ops = &imx_pwm_ops;
+	imx->chip.dev = &pdev->dev;
+	imx->chip.base = -1;
+	imx->chip.npwm = 1;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	imx->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(imx->mmio_base))
+		return PTR_ERR(imx->mmio_base);
+
+	data = of_id->data;
+	imx->config = data->config;
+	imx->set_enable = data->set_enable;
+
+	ret = pwmchip_add(&imx->chip);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, imx);
+	return 0;
+}
+
+static int imx_pwm_remove(struct platform_device *pdev)
+{
+	struct imx_chip *imx;
+
+	imx = platform_get_drvdata(pdev);
+	if (imx == NULL)
+		return -ENODEV;
+
+	return pwmchip_remove(&imx->chip);
+}
+
+static struct platform_driver imx_pwm_driver = {
+	.driver		= {
+		.name	= "imx-pwm",
+		.of_match_table = of_match_ptr(imx_pwm_dt_ids),
+	},
+	.probe		= imx_pwm_probe,
+	.remove		= imx_pwm_remove,
+};
+
+module_platform_driver(imx_pwm_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");

drivers/pwm/pwm-jz4740.c

@@ -0,0 +1,221 @@
+/*
+ *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ *  JZ4740 platform PWM support
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+#include <asm/mach-jz4740/gpio.h>
+#include <asm/mach-jz4740/timer.h>
+
+#define NUM_PWM 8
+
+static const unsigned int jz4740_pwm_gpio_list[NUM_PWM] = {
+	JZ_GPIO_PWM0,
+	JZ_GPIO_PWM1,
+	JZ_GPIO_PWM2,
+	JZ_GPIO_PWM3,
+	JZ_GPIO_PWM4,
+	JZ_GPIO_PWM5,
+	JZ_GPIO_PWM6,
+	JZ_GPIO_PWM7,
+};
+
+struct jz4740_pwm_chip {
+	struct pwm_chip chip;
+	struct clk *clk;
+};
+
+static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip)
+{
+	return container_of(chip, struct jz4740_pwm_chip, chip);
+}
+
+static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm];
+	int ret;
+
+	/*
+	 * Timers 0 and 1 are used for system tasks, so they are unavailable
+	 * for use as PWMs.
+	 */
+	if (pwm->hwpwm < 2)
+		return -EBUSY;
+
+	ret = gpio_request(gpio, pwm->label);
+	if (ret) {
+		dev_err(chip->dev, "Failed to request GPIO#%u for PWM: %d\n",
+			gpio, ret);
+		return ret;
+	}
+
+	jz_gpio_set_function(gpio, JZ_GPIO_FUNC_PWM);
+
+	jz4740_timer_start(pwm->hwpwm);
+
+	return 0;
+}
+
+static void jz4740_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm];
+
+	jz4740_timer_set_ctrl(pwm->hwpwm, 0);
+
+	jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE);
+	gpio_free(gpio);
+
+	jz4740_timer_stop(pwm->hwpwm);
+}
+
+static int jz4740_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	uint32_t ctrl = jz4740_timer_get_ctrl(pwm->pwm);
+
+	ctrl |= JZ_TIMER_CTRL_PWM_ENABLE;
+	jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+	jz4740_timer_enable(pwm->hwpwm);
+
+	return 0;
+}
+
+static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	uint32_t ctrl = jz4740_timer_get_ctrl(pwm->hwpwm);
+
+	ctrl &= ~JZ_TIMER_CTRL_PWM_ENABLE;
+	jz4740_timer_disable(pwm->hwpwm);
+	jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+}
+
+static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			     int duty_ns, int period_ns)
+{
+	struct jz4740_pwm_chip *jz4740 = to_jz4740(pwm->chip);
+	unsigned long long tmp;
+	unsigned long period, duty;
+	unsigned int prescaler = 0;
+	uint16_t ctrl;
+	bool is_enabled;
+
+	tmp = (unsigned long long)clk_get_rate(jz4740->clk) * period_ns;
+	do_div(tmp, 1000000000);
+	period = tmp;
+
+	while (period > 0xffff && prescaler < 6) {
+		period >>= 2;
+		++prescaler;
+	}
+
+	if (prescaler == 6)
+		return -EINVAL;
+
+	tmp = (unsigned long long)period * duty_ns;
+	do_div(tmp, period_ns);
+	duty = period - tmp;
+
+	if (duty >= period)
+		duty = period - 1;
+
+	is_enabled = jz4740_timer_is_enabled(pwm->hwpwm);
+	if (is_enabled)
+		jz4740_pwm_disable(chip, pwm);
+
+	jz4740_timer_set_count(pwm->hwpwm, 0);
+	jz4740_timer_set_duty(pwm->hwpwm, duty);
+	jz4740_timer_set_period(pwm->hwpwm, period);
+
+	ctrl = JZ_TIMER_CTRL_PRESCALER(prescaler) | JZ_TIMER_CTRL_SRC_EXT |
+		JZ_TIMER_CTRL_PWM_ABBRUPT_SHUTDOWN;
+
+	jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+
+	if (is_enabled)
+		jz4740_pwm_enable(chip, pwm);
+
+	return 0;
+}
+
+static const struct pwm_ops jz4740_pwm_ops = {
+	.request = jz4740_pwm_request,
+	.free = jz4740_pwm_free,
+	.config = jz4740_pwm_config,
+	.enable = jz4740_pwm_enable,
+	.disable = jz4740_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int jz4740_pwm_probe(struct platform_device *pdev)
+{
+	struct jz4740_pwm_chip *jz4740;
+	int ret;
+
+	jz4740 = devm_kzalloc(&pdev->dev, sizeof(*jz4740), GFP_KERNEL);
+	if (!jz4740)
+		return -ENOMEM;
+
+	jz4740->clk = clk_get(NULL, "ext");
+	if (IS_ERR(jz4740->clk))
+		return PTR_ERR(jz4740->clk);
+
+	jz4740->chip.dev = &pdev->dev;
+	jz4740->chip.ops = &jz4740_pwm_ops;
+	jz4740->chip.npwm = NUM_PWM;
+	jz4740->chip.base = -1;
+
+	ret = pwmchip_add(&jz4740->chip);
+	if (ret < 0) {
+		clk_put(jz4740->clk);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, jz4740);
+
+	return 0;
+}
+
+static int jz4740_pwm_remove(struct platform_device *pdev)
+{
+	struct jz4740_pwm_chip *jz4740 = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = pwmchip_remove(&jz4740->chip);
+	if (ret < 0)
+		return ret;
+
+	clk_put(jz4740->clk);
+
+	return 0;
+}
+
+static struct platform_driver jz4740_pwm_driver = {
+	.driver = {
+		.name = "jz4740-pwm",
+		.owner = THIS_MODULE,
+	},
+	.probe = jz4740_pwm_probe,
+	.remove = jz4740_pwm_remove,
+};
+module_platform_driver(jz4740_pwm_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Ingenic JZ4740 PWM driver");
+MODULE_ALIAS("platform:jz4740-pwm");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-lpc32xx.c

@@ -0,0 +1,184 @@
+/*
+ * Copyright 2012 Alexandre Pereira da Silva <aletes.xgr@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+struct lpc32xx_pwm_chip {
+	struct pwm_chip chip;
+	struct clk *clk;
+	void __iomem *base;
+};
+
+#define PWM_ENABLE	(1 << 31)
+#define PWM_RELOADV(x)	(((x) & 0xFF) << 8)
+#define PWM_DUTY(x)	((x) & 0xFF)
+
+#define to_lpc32xx_pwm_chip(_chip) \
+	container_of(_chip, struct lpc32xx_pwm_chip, chip)
+
+static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+	unsigned long long c;
+	int period_cycles, duty_cycles;
+	u32 val;
+
+	c = clk_get_rate(lpc32xx->clk) / 256;
+	c = c * period_ns;
+	do_div(c, NSEC_PER_SEC);
+
+	/* Handle high and low extremes */
+	if (c == 0)
+		c = 1;
+	if (c > 255)
+		c = 0; /* 0 set division by 256 */
+	period_cycles = c;
+
+	/* The duty-cycle value is as follows:
+	 *
+	 *  DUTY-CYCLE     HIGH LEVEL
+	 *      1            99.9%
+	 *      25           90.0%
+	 *      128          50.0%
+	 *      220          10.0%
+	 *      255           0.1%
+	 *      0             0.0%
+	 *
+	 * In other words, the register value is duty-cycle % 256 with
+	 * duty-cycle in the range 1-256.
+	 */
+	c = 256 * duty_ns;
+	do_div(c, period_ns);
+	if (c > 255)
+		c = 255;
+	duty_cycles = 256 - c;
+
+	val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+	val &= ~0xFFFF;
+	val |= PWM_RELOADV(period_cycles) | PWM_DUTY(duty_cycles);
+	writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+
+	return 0;
+}
+
+static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+	u32 val;
+	int ret;
+
+	ret = clk_enable(lpc32xx->clk);
+	if (ret)
+		return ret;
+
+	val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+	val |= PWM_ENABLE;
+	writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+
+	return 0;
+}
+
+static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+	u32 val;
+
+	val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+	val &= ~PWM_ENABLE;
+	writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+
+	clk_disable(lpc32xx->clk);
+}
+
+static const struct pwm_ops lpc32xx_pwm_ops = {
+	.config = lpc32xx_pwm_config,
+	.enable = lpc32xx_pwm_enable,
+	.disable = lpc32xx_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int lpc32xx_pwm_probe(struct platform_device *pdev)
+{
+	struct lpc32xx_pwm_chip *lpc32xx;
+	struct resource *res;
+	int ret;
+
+	lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL);
+	if (!lpc32xx)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
+
+	lpc32xx->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(lpc32xx->base))
+		return PTR_ERR(lpc32xx->base);
+
+	lpc32xx->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(lpc32xx->clk))
+		return PTR_ERR(lpc32xx->clk);
+
+	lpc32xx->chip.dev = &pdev->dev;
+	lpc32xx->chip.ops = &lpc32xx_pwm_ops;
+	lpc32xx->chip.npwm = 2;
+	lpc32xx->chip.base = -1;
+
+	ret = pwmchip_add(&lpc32xx->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add PWM chip, error %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, lpc32xx);
+
+	return 0;
+}
+
+static int lpc32xx_pwm_remove(struct platform_device *pdev)
+{
+	struct lpc32xx_pwm_chip *lpc32xx = platform_get_drvdata(pdev);
+	unsigned int i;
+
+	for (i = 0; i < lpc32xx->chip.npwm; i++)
+		pwm_disable(&lpc32xx->chip.pwms[i]);
+
+	return pwmchip_remove(&lpc32xx->chip);
+}
+
+static const struct of_device_id lpc32xx_pwm_dt_ids[] = {
+	{ .compatible = "nxp,lpc3220-pwm", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, lpc32xx_pwm_dt_ids);
+
+static struct platform_driver lpc32xx_pwm_driver = {
+	.driver = {
+		.name = "lpc32xx-pwm",
+		.of_match_table = of_match_ptr(lpc32xx_pwm_dt_ids),
+	},
+	.probe = lpc32xx_pwm_probe,
+	.remove = lpc32xx_pwm_remove,
+};
+module_platform_driver(lpc32xx_pwm_driver);
+
+MODULE_ALIAS("platform:lpc32xx-pwm");
+MODULE_AUTHOR("Alexandre Pereira da Silva <aletes.xgr@gmail.com>");
+MODULE_DESCRIPTION("LPC32XX PWM Driver");
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-mxs.c

@@ -0,0 +1,201 @@
+/*
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/stmp_device.h>
+
+#define SET	0x4
+#define CLR	0x8
+#define TOG	0xc
+
+#define PWM_CTRL		0x0
+#define PWM_ACTIVE0		0x10
+#define PWM_PERIOD0		0x20
+#define  PERIOD_PERIOD(p)	((p) & 0xffff)
+#define  PERIOD_PERIOD_MAX	0x10000
+#define  PERIOD_ACTIVE_HIGH	(3 << 16)
+#define  PERIOD_INACTIVE_LOW	(2 << 18)
+#define  PERIOD_CDIV(div)	(((div) & 0x7) << 20)
+#define  PERIOD_CDIV_MAX	8
+
+struct mxs_pwm_chip {
+	struct pwm_chip chip;
+	struct clk *clk;
+	void __iomem *base;
+};
+
+#define to_mxs_pwm_chip(_chip) container_of(_chip, struct mxs_pwm_chip, chip)
+
+static int mxs_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			  int duty_ns, int period_ns)
+{
+	struct mxs_pwm_chip *mxs = to_mxs_pwm_chip(chip);
+	int ret, div = 0;
+	unsigned int period_cycles, duty_cycles;
+	unsigned long rate;
+	unsigned long long c;
+
+	rate = clk_get_rate(mxs->clk);
+	while (1) {
+		c = rate / (1 << div);
+		c = c * period_ns;
+		do_div(c, 1000000000);
+		if (c < PERIOD_PERIOD_MAX)
+			break;
+		div++;
+		if (div > PERIOD_CDIV_MAX)
+			return -EINVAL;
+	}
+
+	period_cycles = c;
+	c *= duty_ns;
+	do_div(c, period_ns);
+	duty_cycles = c;
+
+	/*
+	 * If the PWM channel is disabled, make sure to turn on the clock
+	 * before writing the register. Otherwise, keep it enabled.
+	 */
+	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+		ret = clk_prepare_enable(mxs->clk);
+		if (ret)
+			return ret;
+	}
+
+	writel(duty_cycles << 16,
+			mxs->base + PWM_ACTIVE0 + pwm->hwpwm * 0x20);
+	writel(PERIOD_PERIOD(period_cycles) | PERIOD_ACTIVE_HIGH |
+	       PERIOD_INACTIVE_LOW | PERIOD_CDIV(div),
+			mxs->base + PWM_PERIOD0 + pwm->hwpwm * 0x20);
+
+	/*
+	 * If the PWM is not enabled, turn the clock off again to save power.
+	 */
+	if (!test_bit(PWMF_ENABLED, &pwm->flags))
+		clk_disable_unprepare(mxs->clk);
+
+	return 0;
+}
+
+static int mxs_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct mxs_pwm_chip *mxs = to_mxs_pwm_chip(chip);
+	int ret;
+
+	ret = clk_prepare_enable(mxs->clk);
+	if (ret)
+		return ret;
+
+	writel(1 << pwm->hwpwm, mxs->base + PWM_CTRL + SET);
+
+	return 0;
+}
+
+static void mxs_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct mxs_pwm_chip *mxs = to_mxs_pwm_chip(chip);
+
+	writel(1 << pwm->hwpwm, mxs->base + PWM_CTRL + CLR);
+
+	clk_disable_unprepare(mxs->clk);
+}
+
+static const struct pwm_ops mxs_pwm_ops = {
+	.config = mxs_pwm_config,
+	.enable = mxs_pwm_enable,
+	.disable = mxs_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int mxs_pwm_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mxs_pwm_chip *mxs;
+	struct resource *res;
+	struct pinctrl *pinctrl;
+	int ret;
+
+	mxs = devm_kzalloc(&pdev->dev, sizeof(*mxs), GFP_KERNEL);
+	if (!mxs)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mxs->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mxs->base))
+		return PTR_ERR(mxs->base);
+
+	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+	if (IS_ERR(pinctrl))
+		return PTR_ERR(pinctrl);
+
+	mxs->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(mxs->clk))
+		return PTR_ERR(mxs->clk);
+
+	mxs->chip.dev = &pdev->dev;
+	mxs->chip.ops = &mxs_pwm_ops;
+	mxs->chip.base = -1;
+	ret = of_property_read_u32(np, "fsl,pwm-number", &mxs->chip.npwm);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);
+		return ret;
+	}
+
+	ret = pwmchip_add(&mxs->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add pwm chip %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, mxs);
+
+	stmp_reset_block(mxs->base);
+
+	return 0;
+}
+
+static int mxs_pwm_remove(struct platform_device *pdev)
+{
+	struct mxs_pwm_chip *mxs = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&mxs->chip);
+}
+
+static const struct of_device_id mxs_pwm_dt_ids[] = {
+	{ .compatible = "fsl,imx23-pwm", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_pwm_dt_ids);
+
+static struct platform_driver mxs_pwm_driver = {
+	.driver = {
+		.name = "mxs-pwm",
+		.of_match_table = of_match_ptr(mxs_pwm_dt_ids),
+	},
+	.probe = mxs_pwm_probe,
+	.remove = mxs_pwm_remove,
+};
+module_platform_driver(mxs_pwm_driver);
+
+MODULE_ALIAS("platform:mxs-pwm");
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_DESCRIPTION("Freescale MXS PWM Driver");
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-puv3.c

@@ -0,0 +1,155 @@
+/*
+ * linux/arch/unicore32/kernel/pwm.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ *	Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
+ *	Copyright (C) 2001-2010 Guan Xuetao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+
+#include <asm/div64.h>
+#include <mach/hardware.h>
+
+struct puv3_pwm_chip {
+	struct pwm_chip chip;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+static inline struct puv3_pwm_chip *to_puv3(struct pwm_chip *chip)
+{
+	return container_of(chip, struct puv3_pwm_chip, chip);
+}
+
+/*
+ * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE
+ * duty_ns   = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
+ */
+static int puv3_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			   int duty_ns, int period_ns)
+{
+	unsigned long period_cycles, prescale, pv, dc;
+	struct puv3_pwm_chip *puv3 = to_puv3(chip);
+	unsigned long long c;
+
+	c = clk_get_rate(puv3->clk);
+	c = c * period_ns;
+	do_div(c, 1000000000);
+	period_cycles = c;
+
+	if (period_cycles < 1)
+		period_cycles = 1;
+
+	prescale = (period_cycles - 1) / 1024;
+	pv = period_cycles / (prescale + 1) - 1;
+
+	if (prescale > 63)
+		return -EINVAL;
+
+	if (duty_ns == period_ns)
+		dc = OST_PWMDCCR_FDCYCLE;
+	else
+		dc = (pv + 1) * duty_ns / period_ns;
+
+	/*
+	 * NOTE: the clock to PWM has to be enabled first
+	 * before writing to the registers
+	 */
+	clk_prepare_enable(puv3->clk);
+
+	writel(prescale, puv3->base + OST_PWM_PWCR);
+	writel(pv - dc, puv3->base + OST_PWM_DCCR);
+	writel(pv, puv3->base + OST_PWM_PCR);
+
+	clk_disable_unprepare(puv3->clk);
+
+	return 0;
+}
+
+static int puv3_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct puv3_pwm_chip *puv3 = to_puv3(chip);
+
+	return clk_prepare_enable(puv3->clk);
+}
+
+static void puv3_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct puv3_pwm_chip *puv3 = to_puv3(chip);
+
+	clk_disable_unprepare(puv3->clk);
+}
+
+static const struct pwm_ops puv3_pwm_ops = {
+	.config = puv3_pwm_config,
+	.enable = puv3_pwm_enable,
+	.disable = puv3_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int pwm_probe(struct platform_device *pdev)
+{
+	struct puv3_pwm_chip *puv3;
+	struct resource *r;
+	int ret;
+
+	puv3 = devm_kzalloc(&pdev->dev, sizeof(*puv3), GFP_KERNEL);
+	if (puv3 == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	puv3->clk = devm_clk_get(&pdev->dev, "OST_CLK");
+	if (IS_ERR(puv3->clk))
+		return PTR_ERR(puv3->clk);
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	puv3->base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(puv3->base))
+		return PTR_ERR(puv3->base);
+
+	puv3->chip.dev = &pdev->dev;
+	puv3->chip.ops = &puv3_pwm_ops;
+	puv3->chip.base = -1;
+	puv3->chip.npwm = 1;
+
+	ret = pwmchip_add(&puv3->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, puv3);
+	return 0;
+}
+
+static int pwm_remove(struct platform_device *pdev)
+{
+	struct puv3_pwm_chip *puv3 = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&puv3->chip);
+}
+
+static struct platform_driver puv3_pwm_driver = {
+	.driver = {
+		.name = "PKUnity-v3-PWM",
+	},
+	.probe = pwm_probe,
+	.remove = pwm_remove,
+};
+module_platform_driver(puv3_pwm_driver);
+
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-pxa.c

@@ -0,0 +1,197 @@
+/*
+ * drivers/pwm/pwm-pxa.c
+ *
+ * simple driver for PWM (Pulse Width Modulator) controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 2008-02-13	initial version
+ * 		eric miao <eric.miao@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+
+#include <asm/div64.h>
+
+#define HAS_SECONDARY_PWM	0x10
+
+static const struct platform_device_id pwm_id_table[] = {
+	/*   PWM    has_secondary_pwm? */
+	{ "pxa25x-pwm", 0 },
+	{ "pxa27x-pwm", HAS_SECONDARY_PWM },
+	{ "pxa168-pwm", 0 },
+	{ "pxa910-pwm", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, pwm_id_table);
+
+/* PWM registers and bits definitions */
+#define PWMCR		(0x00)
+#define PWMDCR		(0x04)
+#define PWMPCR		(0x08)
+
+#define PWMCR_SD	(1 << 6)
+#define PWMDCR_FD	(1 << 10)
+
+struct pxa_pwm_chip {
+	struct pwm_chip	chip;
+	struct device	*dev;
+
+	struct clk	*clk;
+	void __iomem	*mmio_base;
+};
+
+static inline struct pxa_pwm_chip *to_pxa_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct pxa_pwm_chip, chip);
+}
+
+/*
+ * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE
+ * duty_ns   = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
+ */
+static int pxa_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			  int duty_ns, int period_ns)
+{
+	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
+	unsigned long long c;
+	unsigned long period_cycles, prescale, pv, dc;
+	unsigned long offset;
+	int rc;
+
+	offset = pwm->hwpwm ? 0x10 : 0;
+
+	c = clk_get_rate(pc->clk);
+	c = c * period_ns;
+	do_div(c, 1000000000);
+	period_cycles = c;
+
+	if (period_cycles < 1)
+		period_cycles = 1;
+	prescale = (period_cycles - 1) / 1024;
+	pv = period_cycles / (prescale + 1) - 1;
+
+	if (prescale > 63)
+		return -EINVAL;
+
+	if (duty_ns == period_ns)
+		dc = PWMDCR_FD;
+	else
+		dc = (pv + 1) * duty_ns / period_ns;
+
+	/* NOTE: the clock to PWM has to be enabled first
+	 * before writing to the registers
+	 */
+	rc = clk_prepare_enable(pc->clk);
+	if (rc < 0)
+		return rc;
+
+	writel(prescale, pc->mmio_base + offset + PWMCR);
+	writel(dc, pc->mmio_base + offset + PWMDCR);
+	writel(pv, pc->mmio_base + offset + PWMPCR);
+
+	clk_disable_unprepare(pc->clk);
+	return 0;
+}
+
+static int pxa_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
+
+	return clk_prepare_enable(pc->clk);
+}
+
+static void pxa_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
+
+	clk_disable_unprepare(pc->clk);
+}
+
+static struct pwm_ops pxa_pwm_ops = {
+	.config = pxa_pwm_config,
+	.enable = pxa_pwm_enable,
+	.disable = pxa_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int pwm_probe(struct platform_device *pdev)
+{
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+	struct pxa_pwm_chip *pwm;
+	struct resource *r;
+	int ret = 0;
+
+	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+	if (pwm == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	pwm->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(pwm->clk))
+		return PTR_ERR(pwm->clk);
+
+	pwm->chip.dev = &pdev->dev;
+	pwm->chip.ops = &pxa_pwm_ops;
+	pwm->chip.base = -1;
+	pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(pwm->mmio_base))
+		return PTR_ERR(pwm->mmio_base);
+
+	ret = pwmchip_add(&pwm->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, pwm);
+	return 0;
+}
+
+static int pwm_remove(struct platform_device *pdev)
+{
+	struct pxa_pwm_chip *chip;
+
+	chip = platform_get_drvdata(pdev);
+	if (chip == NULL)
+		return -ENODEV;
+
+	return pwmchip_remove(&chip->chip);
+}
+
+static struct platform_driver pwm_driver = {
+	.driver		= {
+		.name	= "pxa25x-pwm",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= pwm_probe,
+	.remove		= pwm_remove,
+	.id_table	= pwm_id_table,
+};
+
+static int __init pwm_init(void)
+{
+	return platform_driver_register(&pwm_driver);
+}
+arch_initcall(pwm_init);
+
+static void __exit pwm_exit(void)
+{
+	platform_driver_unregister(&pwm_driver);
+}
+module_exit(pwm_exit);
+
+MODULE_LICENSE("GPL v2");

drivers/pwm/pwm-samsung.c

@@ -0,0 +1,353 @@
+/* drivers/pwm/pwm-samsung.c
+ *
+ * Copyright (c) 2007 Ben Dooks
+ * Copyright (c) 2008 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
+ *
+ * S3C series PWM device core
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License.
+*/
+
+#define pr_fmt(fmt) "pwm-samsung: " fmt
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+
+#include <mach/map.h>
+
+#include <plat/regs-timer.h>
+
+struct s3c_chip {
+	struct platform_device	*pdev;
+
+	struct clk		*clk_div;
+	struct clk		*clk;
+	const char		*label;
+
+	unsigned int		 period_ns;
+	unsigned int		 duty_ns;
+
+	unsigned char		 tcon_base;
+	unsigned char		 pwm_id;
+	struct pwm_chip		 chip;
+};
+
+#define to_s3c_chip(chip)	container_of(chip, struct s3c_chip, chip)
+
+#define pwm_dbg(_pwm, msg...) dev_dbg(&(_pwm)->pdev->dev, msg)
+
+static struct clk *clk_scaler[2];
+
+static inline int pwm_is_tdiv(struct s3c_chip *chip)
+{
+	return clk_get_parent(chip->clk) == chip->clk_div;
+}
+
+#define pwm_tcon_start(pwm) (1 << (pwm->tcon_base + 0))
+#define pwm_tcon_invert(pwm) (1 << (pwm->tcon_base + 2))
+#define pwm_tcon_autoreload(pwm) (1 << (pwm->tcon_base + 3))
+#define pwm_tcon_manulupdate(pwm) (1 << (pwm->tcon_base + 1))
+
+static int s3c_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct s3c_chip *s3c = to_s3c_chip(chip);
+	unsigned long flags;
+	unsigned long tcon;
+
+	local_irq_save(flags);
+
+	tcon = __raw_readl(S3C2410_TCON);
+	tcon |= pwm_tcon_start(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+static void s3c_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct s3c_chip *s3c = to_s3c_chip(chip);
+	unsigned long flags;
+	unsigned long tcon;
+
+	local_irq_save(flags);
+
+	tcon = __raw_readl(S3C2410_TCON);
+	tcon &= ~pwm_tcon_start(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	local_irq_restore(flags);
+}
+
+static unsigned long pwm_calc_tin(struct s3c_chip *s3c, unsigned long freq)
+{
+	unsigned long tin_parent_rate;
+	unsigned int div;
+
+	tin_parent_rate = clk_get_rate(clk_get_parent(s3c->clk_div));
+	pwm_dbg(s3c, "tin parent at %lu\n", tin_parent_rate);
+
+	for (div = 2; div <= 16; div *= 2) {
+		if ((tin_parent_rate / (div << 16)) < freq)
+			return tin_parent_rate / div;
+	}
+
+	return tin_parent_rate / 16;
+}
+
+#define NS_IN_HZ (1000000000UL)
+
+static int s3c_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
+{
+	struct s3c_chip *s3c = to_s3c_chip(chip);
+	unsigned long tin_rate;
+	unsigned long tin_ns;
+	unsigned long period;
+	unsigned long flags;
+	unsigned long tcon;
+	unsigned long tcnt;
+	long tcmp;
+
+	/* We currently avoid using 64bit arithmetic by using the
+	 * fact that anything faster than 1Hz is easily representable
+	 * by 32bits. */
+
+	if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
+		return -ERANGE;
+
+	if (period_ns == s3c->period_ns &&
+	    duty_ns == s3c->duty_ns)
+		return 0;
+
+	/* The TCMP and TCNT can be read without a lock, they're not
+	 * shared between the timers. */
+
+	tcmp = __raw_readl(S3C2410_TCMPB(s3c->pwm_id));
+	tcnt = __raw_readl(S3C2410_TCNTB(s3c->pwm_id));
+
+	period = NS_IN_HZ / period_ns;
+
+	pwm_dbg(s3c, "duty_ns=%d, period_ns=%d (%lu)\n",
+		duty_ns, period_ns, period);
+
+	/* Check to see if we are changing the clock rate of the PWM */
+
+	if (s3c->period_ns != period_ns) {
+		if (pwm_is_tdiv(s3c)) {
+			tin_rate = pwm_calc_tin(s3c, period);
+			clk_set_rate(s3c->clk_div, tin_rate);
+		} else
+			tin_rate = clk_get_rate(s3c->clk);
+
+		s3c->period_ns = period_ns;
+
+		pwm_dbg(s3c, "tin_rate=%lu\n", tin_rate);
+
+		tin_ns = NS_IN_HZ / tin_rate;
+		tcnt = period_ns / tin_ns;
+	} else
+		tin_ns = NS_IN_HZ / clk_get_rate(s3c->clk);
+
+	/* Note, counters count down */
+
+	tcmp = duty_ns / tin_ns;
+	tcmp = tcnt - tcmp;
+	/* the pwm hw only checks the compare register after a decrement,
+	   so the pin never toggles if tcmp = tcnt */
+	if (tcmp == tcnt)
+		tcmp--;
+
+	pwm_dbg(s3c, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);
+
+	if (tcmp < 0)
+		tcmp = 0;
+
+	/* Update the PWM register block. */
+
+	local_irq_save(flags);
+
+	__raw_writel(tcmp, S3C2410_TCMPB(s3c->pwm_id));
+	__raw_writel(tcnt, S3C2410_TCNTB(s3c->pwm_id));
+
+	tcon = __raw_readl(S3C2410_TCON);
+	tcon |= pwm_tcon_manulupdate(s3c);
+	tcon |= pwm_tcon_autoreload(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	tcon &= ~pwm_tcon_manulupdate(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+static struct pwm_ops s3c_pwm_ops = {
+	.enable = s3c_pwm_enable,
+	.disable = s3c_pwm_disable,
+	.config = s3c_pwm_config,
+	.owner = THIS_MODULE,
+};
+
+static int s3c_pwm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct s3c_chip *s3c;
+	unsigned long flags;
+	unsigned long tcon;
+	unsigned int id = pdev->id;
+	int ret;
+
+	if (id == 4) {
+		dev_err(dev, "TIMER4 is currently not supported\n");
+		return -ENXIO;
+	}
+
+	s3c = devm_kzalloc(&pdev->dev, sizeof(*s3c), GFP_KERNEL);
+	if (s3c == NULL) {
+		dev_err(dev, "failed to allocate pwm_device\n");
+		return -ENOMEM;
+	}
+
+	/* calculate base of control bits in TCON */
+	s3c->tcon_base = id == 0 ? 0 : (id * 4) + 4;
+	s3c->pwm_id = id;
+	s3c->chip.dev = &pdev->dev;
+	s3c->chip.ops = &s3c_pwm_ops;
+	s3c->chip.base = -1;
+	s3c->chip.npwm = 1;
+
+	s3c->clk = devm_clk_get(dev, "pwm-tin");
+	if (IS_ERR(s3c->clk)) {
+		dev_err(dev, "failed to get pwm tin clk\n");
+		return PTR_ERR(s3c->clk);
+	}
+
+	s3c->clk_div = devm_clk_get(dev, "pwm-tdiv");
+	if (IS_ERR(s3c->clk_div)) {
+		dev_err(dev, "failed to get pwm tdiv clk\n");
+		return PTR_ERR(s3c->clk_div);
+	}
+
+	clk_enable(s3c->clk);
+	clk_enable(s3c->clk_div);
+
+	local_irq_save(flags);
+
+	tcon = __raw_readl(S3C2410_TCON);
+	tcon |= pwm_tcon_invert(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	local_irq_restore(flags);
+
+	ret = pwmchip_add(&s3c->chip);
+	if (ret < 0) {
+		dev_err(dev, "failed to register pwm\n");
+		goto err_clk_tdiv;
+	}
+
+	pwm_dbg(s3c, "config bits %02x\n",
+		(__raw_readl(S3C2410_TCON) >> s3c->tcon_base) & 0x0f);
+
+	dev_info(dev, "tin at %lu, tdiv at %lu, tin=%sclk, base %d\n",
+		 clk_get_rate(s3c->clk),
+		 clk_get_rate(s3c->clk_div),
+		 pwm_is_tdiv(s3c) ? "div" : "ext", s3c->tcon_base);
+
+	platform_set_drvdata(pdev, s3c);
+	return 0;
+
+ err_clk_tdiv:
+	clk_disable(s3c->clk_div);
+	clk_disable(s3c->clk);
+	return ret;
+}
+
+static int s3c_pwm_remove(struct platform_device *pdev)
+{
+	struct s3c_chip *s3c = platform_get_drvdata(pdev);
+	int err;
+
+	err = pwmchip_remove(&s3c->chip);
+	if (err < 0)
+		return err;
+
+	clk_disable(s3c->clk_div);
+	clk_disable(s3c->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int s3c_pwm_suspend(struct device *dev)
+{
+	struct s3c_chip *s3c = dev_get_drvdata(dev);
+
+	/* No one preserve these values during suspend so reset them
+	 * Otherwise driver leaves PWM unconfigured if same values
+	 * passed to pwm_config
+	 */
+	s3c->period_ns = 0;
+	s3c->duty_ns = 0;
+
+	return 0;
+}
+
+static int s3c_pwm_resume(struct device *dev)
+{
+	struct s3c_chip *s3c = dev_get_drvdata(dev);
+	unsigned long tcon;
+
+	/* Restore invertion */
+	tcon = __raw_readl(S3C2410_TCON);
+	tcon |= pwm_tcon_invert(s3c);
+	__raw_writel(tcon, S3C2410_TCON);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(s3c_pwm_pm_ops, s3c_pwm_suspend,
+			s3c_pwm_resume);
+
+static struct platform_driver s3c_pwm_driver = {
+	.driver		= {
+		.name	= "s3c24xx-pwm",
+		.owner	= THIS_MODULE,
+		.pm	= &s3c_pwm_pm_ops,
+	},
+	.probe		= s3c_pwm_probe,
+	.remove		= s3c_pwm_remove,
+};
+
+static int __init pwm_init(void)
+{
+	int ret;
+
+	clk_scaler[0] = clk_get(NULL, "pwm-scaler0");
+	clk_scaler[1] = clk_get(NULL, "pwm-scaler1");
+
+	if (IS_ERR(clk_scaler[0]) || IS_ERR(clk_scaler[1])) {
+		pr_err("failed to get scaler clocks\n");
+		return -EINVAL;
+	}
+
+	ret = platform_driver_register(&s3c_pwm_driver);
+	if (ret)
+		pr_err("failed to add pwm driver\n");
+
+	return ret;
+}
+
+arch_initcall(pwm_init);

drivers/pwm/pwm-spear.c

@@ -0,0 +1,273 @@
+/*
+ * ST Microelectronics SPEAr Pulse Width Modulator driver
+ *
+ * Copyright (C) 2012 ST Microelectronics
+ * Shiraz Hashim <shiraz.hashim@st.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define NUM_PWM		4
+
+/* PWM registers and bits definitions */
+#define PWMCR			0x00	/* Control Register */
+#define PWMCR_PWM_ENABLE	0x1
+#define PWMCR_PRESCALE_SHIFT	2
+#define PWMCR_MIN_PRESCALE	0x00
+#define PWMCR_MAX_PRESCALE	0x3FFF
+
+#define PWMDCR			0x04	/* Duty Cycle Register */
+#define PWMDCR_MIN_DUTY		0x0001
+#define PWMDCR_MAX_DUTY		0xFFFF
+
+#define PWMPCR			0x08	/* Period Register */
+#define PWMPCR_MIN_PERIOD	0x0001
+#define PWMPCR_MAX_PERIOD	0xFFFF
+
+/* Following only available on 13xx SoCs */
+#define PWMMCR			0x3C	/* Master Control Register */
+#define PWMMCR_PWM_ENABLE	0x1
+
+/**
+ * struct spear_pwm_chip - struct representing pwm chip
+ *
+ * @mmio_base: base address of pwm chip
+ * @clk: pointer to clk structure of pwm chip
+ * @chip: linux pwm chip representation
+ */
+struct spear_pwm_chip {
+	void __iomem *mmio_base;
+	struct clk *clk;
+	struct pwm_chip chip;
+};
+
+static inline struct spear_pwm_chip *to_spear_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct spear_pwm_chip, chip);
+}
+
+static inline u32 spear_pwm_readl(struct spear_pwm_chip *chip, unsigned int num,
+				  unsigned long offset)
+{
+	return readl_relaxed(chip->mmio_base + (num << 4) + offset);
+}
+
+static inline void spear_pwm_writel(struct spear_pwm_chip *chip,
+				    unsigned int num, unsigned long offset,
+				    unsigned long val)
+{
+	writel_relaxed(val, chip->mmio_base + (num << 4) + offset);
+}
+
+static int spear_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			    int duty_ns, int period_ns)
+{
+	struct spear_pwm_chip *pc = to_spear_pwm_chip(chip);
+	u64 val, div, clk_rate;
+	unsigned long prescale = PWMCR_MIN_PRESCALE, pv, dc;
+	int ret;
+
+	/*
+	 * Find pv, dc and prescale to suit duty_ns and period_ns. This is done
+	 * according to formulas described below:
+	 *
+	 * period_ns = 10^9 * (PRESCALE + 1) * PV / PWM_CLK_RATE
+	 * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
+	 *
+	 * PV = (PWM_CLK_RATE * period_ns) / (10^9 * (PRESCALE + 1))
+	 * DC = (PWM_CLK_RATE * duty_ns) / (10^9 * (PRESCALE + 1))
+	 */
+	clk_rate = clk_get_rate(pc->clk);
+	while (1) {
+		div = 1000000000;
+		div *= 1 + prescale;
+		val = clk_rate * period_ns;
+		pv = div64_u64(val, div);
+		val = clk_rate * duty_ns;
+		dc = div64_u64(val, div);
+
+		/* if duty_ns and period_ns are not achievable then return */
+		if (pv < PWMPCR_MIN_PERIOD || dc < PWMDCR_MIN_DUTY)
+			return -EINVAL;
+
+		/*
+		 * if pv and dc have crossed their upper limit, then increase
+		 * prescale and recalculate pv and dc.
+		 */
+		if (pv > PWMPCR_MAX_PERIOD || dc > PWMDCR_MAX_DUTY) {
+			if (++prescale > PWMCR_MAX_PRESCALE)
+				return -EINVAL;
+			continue;
+		}
+		break;
+	}
+
+	/*
+	 * NOTE: the clock to PWM has to be enabled first before writing to the
+	 * registers.
+	 */
+	ret = clk_enable(pc->clk);
+	if (ret)
+		return ret;
+
+	spear_pwm_writel(pc, pwm->hwpwm, PWMCR,
+			prescale << PWMCR_PRESCALE_SHIFT);
+	spear_pwm_writel(pc, pwm->hwpwm, PWMDCR, dc);
+	spear_pwm_writel(pc, pwm->hwpwm, PWMPCR, pv);
+	clk_disable(pc->clk);
+
+	return 0;
+}
+
+static int spear_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct spear_pwm_chip *pc = to_spear_pwm_chip(chip);
+	int rc = 0;
+	u32 val;
+
+	rc = clk_enable(pc->clk);
+	if (rc)
+		return rc;
+
+	val = spear_pwm_readl(pc, pwm->hwpwm, PWMCR);
+	val |= PWMCR_PWM_ENABLE;
+	spear_pwm_writel(pc, pwm->hwpwm, PWMCR, val);
+
+	return 0;
+}
+
+static void spear_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct spear_pwm_chip *pc = to_spear_pwm_chip(chip);
+	u32 val;
+
+	val = spear_pwm_readl(pc, pwm->hwpwm, PWMCR);
+	val &= ~PWMCR_PWM_ENABLE;
+	spear_pwm_writel(pc, pwm->hwpwm, PWMCR, val);
+
+	clk_disable(pc->clk);
+}
+
+static const struct pwm_ops spear_pwm_ops = {
+	.config = spear_pwm_config,
+	.enable = spear_pwm_enable,
+	.disable = spear_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int spear_pwm_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct spear_pwm_chip *pc;
+	struct resource *r;
+	int ret;
+	u32 val;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		dev_err(&pdev->dev, "no memory resources defined\n");
+		return -ENODEV;
+	}
+
+	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
+	if (!pc) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	pc->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(pc->mmio_base))
+		return PTR_ERR(pc->mmio_base);
+
+	pc->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(pc->clk))
+		return PTR_ERR(pc->clk);
+
+	platform_set_drvdata(pdev, pc);
+
+	pc->chip.dev = &pdev->dev;
+	pc->chip.ops = &spear_pwm_ops;
+	pc->chip.base = -1;
+	pc->chip.npwm = NUM_PWM;
+
+	ret = clk_prepare(pc->clk);
+	if (ret)
+		return ret;
+
+	if (of_device_is_compatible(np, "st,spear1340-pwm")) {
+		ret = clk_enable(pc->clk);
+		if (ret) {
+			clk_unprepare(pc->clk);
+			return ret;
+		}
+		/*
+		 * Following enables PWM chip, channels would still be
+		 * enabled individually through their control register
+		 */
+		val = readl_relaxed(pc->mmio_base + PWMMCR);
+		val |= PWMMCR_PWM_ENABLE;
+		writel_relaxed(val, pc->mmio_base + PWMMCR);
+
+		clk_disable(pc->clk);
+	}
+
+	ret = pwmchip_add(&pc->chip);
+	if (!ret) {
+		clk_unprepare(pc->clk);
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+	}
+
+	return ret;
+}
+
+static int spear_pwm_remove(struct platform_device *pdev)
+{
+	struct spear_pwm_chip *pc = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < NUM_PWM; i++)
+		pwm_disable(&pc->chip.pwms[i]);
+
+	/* clk was prepared in probe, hence unprepare it here */
+	clk_unprepare(pc->clk);
+	return pwmchip_remove(&pc->chip);
+}
+
+static const struct of_device_id spear_pwm_of_match[] = {
+	{ .compatible = "st,spear320-pwm" },
+	{ .compatible = "st,spear1340-pwm" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, spear_pwm_of_match);
+
+static struct platform_driver spear_pwm_driver = {
+	.driver = {
+		.name = "spear-pwm",
+		.of_match_table = spear_pwm_of_match,
+	},
+	.probe = spear_pwm_probe,
+	.remove = spear_pwm_remove,
+};
+
+module_platform_driver(spear_pwm_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Shiraz Hashim <shiraz.hashim@st.com>");
+MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.com>");
+MODULE_ALIAS("platform:spear-pwm");

drivers/pwm/pwm-tegra.c

@@ -0,0 +1,252 @@
+/*
+ * drivers/pwm/pwm-tegra.c
+ *
+ * Tegra pulse-width-modulation controller driver
+ *
+ * Copyright (c) 2010, NVIDIA Corporation.
+ * Based on arch/arm/plat-mxc/pwm.c by Sascha Hauer <s.hauer@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pwm.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define PWM_ENABLE	(1 << 31)
+#define PWM_DUTY_WIDTH	8
+#define PWM_DUTY_SHIFT	16
+#define PWM_SCALE_WIDTH	13
+#define PWM_SCALE_SHIFT	0
+
+#define NUM_PWM 4
+
+struct tegra_pwm_chip {
+	struct pwm_chip		chip;
+	struct device		*dev;
+
+	struct clk		*clk;
+
+	void __iomem		*mmio_base;
+};
+
+static inline struct tegra_pwm_chip *to_tegra_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct tegra_pwm_chip, chip);
+}
+
+static inline u32 pwm_readl(struct tegra_pwm_chip *chip, unsigned int num)
+{
+	return readl(chip->mmio_base + (num << 4));
+}
+
+static inline void pwm_writel(struct tegra_pwm_chip *chip, unsigned int num,
+			     unsigned long val)
+{
+	writel(val, chip->mmio_base + (num << 4));
+}
+
+static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			    int duty_ns, int period_ns)
+{
+	struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip);
+	unsigned long long c;
+	unsigned long rate, hz;
+	u32 val = 0;
+	int err;
+
+	/*
+	 * Convert from duty_ns / period_ns to a fixed number of duty ticks
+	 * per (1 << PWM_DUTY_WIDTH) cycles and make sure to round to the
+	 * nearest integer during division.
+	 */
+	c = duty_ns * (1 << PWM_DUTY_WIDTH) + period_ns / 2;
+	do_div(c, period_ns);
+
+	val = (u32)c << PWM_DUTY_SHIFT;
+
+	/*
+	 * Compute the prescaler value for which (1 << PWM_DUTY_WIDTH)
+	 * cycles at the PWM clock rate will take period_ns nanoseconds.
+	 */
+	rate = clk_get_rate(pc->clk) >> PWM_DUTY_WIDTH;
+	hz = 1000000000ul / period_ns;
+
+	rate = (rate + (hz / 2)) / hz;
+
+	/*
+	 * Since the actual PWM divider is the register's frequency divider
+	 * field minus 1, we need to decrement to get the correct value to
+	 * write to the register.
+	 */
+	if (rate > 0)
+		rate--;
+
+	/*
+	 * Make sure that the rate will fit in the register's frequency
+	 * divider field.
+	 */
+	if (rate >> PWM_SCALE_WIDTH)
+		return -EINVAL;
+
+	val |= rate << PWM_SCALE_SHIFT;
+
+	/*
+	 * If the PWM channel is disabled, make sure to turn on the clock
+	 * before writing the register. Otherwise, keep it enabled.
+	 */
+	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+		err = clk_prepare_enable(pc->clk);
+		if (err < 0)
+			return err;
+	} else
+		val |= PWM_ENABLE;
+
+	pwm_writel(pc, pwm->hwpwm, val);
+
+	/*
+	 * If the PWM is not enabled, turn the clock off again to save power.
+	 */
+	if (!test_bit(PWMF_ENABLED, &pwm->flags))
+		clk_disable_unprepare(pc->clk);
+
+	return 0;
+}
+
+static int tegra_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip);
+	int rc = 0;
+	u32 val;
+
+	rc = clk_prepare_enable(pc->clk);
+	if (rc < 0)
+		return rc;
+
+	val = pwm_readl(pc, pwm->hwpwm);
+	val |= PWM_ENABLE;
+	pwm_writel(pc, pwm->hwpwm, val);
+
+	return 0;
+}
+
+static void tegra_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip);
+	u32 val;
+
+	val = pwm_readl(pc, pwm->hwpwm);
+	val &= ~PWM_ENABLE;
+	pwm_writel(pc, pwm->hwpwm, val);
+
+	clk_disable_unprepare(pc->clk);
+}
+
+static const struct pwm_ops tegra_pwm_ops = {
+	.config = tegra_pwm_config,
+	.enable = tegra_pwm_enable,
+	.disable = tegra_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int tegra_pwm_probe(struct platform_device *pdev)
+{
+	struct tegra_pwm_chip *pwm;
+	struct resource *r;
+	int ret;
+
+	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+	if (!pwm) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	pwm->dev = &pdev->dev;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(pwm->mmio_base))
+		return PTR_ERR(pwm->mmio_base);
+
+	platform_set_drvdata(pdev, pwm);
+
+	pwm->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(pwm->clk))
+		return PTR_ERR(pwm->clk);
+
+	pwm->chip.dev = &pdev->dev;
+	pwm->chip.ops = &tegra_pwm_ops;
+	pwm->chip.base = -1;
+	pwm->chip.npwm = NUM_PWM;
+
+	ret = pwmchip_add(&pwm->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int tegra_pwm_remove(struct platform_device *pdev)
+{
+	struct tegra_pwm_chip *pc = platform_get_drvdata(pdev);
+	int i;
+
+	if (WARN_ON(!pc))
+		return -ENODEV;
+
+	for (i = 0; i < NUM_PWM; i++) {
+		struct pwm_device *pwm = &pc->chip.pwms[i];
+
+		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+			if (clk_prepare_enable(pc->clk) < 0)
+				continue;
+
+		pwm_writel(pc, i, 0);
+
+		clk_disable_unprepare(pc->clk);
+	}
+
+	return pwmchip_remove(&pc->chip);
+}
+
+static const struct of_device_id tegra_pwm_of_match[] = {
+	{ .compatible = "nvidia,tegra20-pwm" },
+	{ .compatible = "nvidia,tegra30-pwm" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, tegra_pwm_of_match);
+
+static struct platform_driver tegra_pwm_driver = {
+	.driver = {
+		.name = "tegra-pwm",
+		.of_match_table = tegra_pwm_of_match,
+	},
+	.probe = tegra_pwm_probe,
+	.remove = tegra_pwm_remove,
+};
+
+module_platform_driver(tegra_pwm_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("NVIDIA Corporation");
+MODULE_ALIAS("platform:tegra-pwm");

drivers/pwm/pwm-tiecap.c

@@ -0,0 +1,355 @@
+/*
+ * ECAP PWM driver
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc. - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+
+#include "pwm-tipwmss.h"
+
+/* ECAP registers and bits definitions */
+#define CAP1			0x08
+#define CAP2			0x0C
+#define CAP3			0x10
+#define CAP4			0x14
+#define ECCTL2			0x2A
+#define ECCTL2_APWM_POL_LOW	BIT(10)
+#define ECCTL2_APWM_MODE	BIT(9)
+#define ECCTL2_SYNC_SEL_DISA	(BIT(7) | BIT(6))
+#define ECCTL2_TSCTR_FREERUN	BIT(4)
+
+struct ecap_context {
+	u32	cap3;
+	u32	cap4;
+	u16	ecctl2;
+};
+
+struct ecap_pwm_chip {
+	struct pwm_chip	chip;
+	unsigned int	clk_rate;
+	void __iomem	*mmio_base;
+	struct ecap_context ctx;
+};
+
+static inline struct ecap_pwm_chip *to_ecap_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct ecap_pwm_chip, chip);
+}
+
+/*
+ * period_ns = 10^9 * period_cycles / PWM_CLK_RATE
+ * duty_ns   = 10^9 * duty_cycles / PWM_CLK_RATE
+ */
+static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
+{
+	struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
+	unsigned long long c;
+	unsigned long period_cycles, duty_cycles;
+	unsigned int reg_val;
+
+	if (period_ns > NSEC_PER_SEC)
+		return -ERANGE;
+
+	c = pc->clk_rate;
+	c = c * period_ns;
+	do_div(c, NSEC_PER_SEC);
+	period_cycles = (unsigned long)c;
+
+	if (period_cycles < 1) {
+		period_cycles = 1;
+		duty_cycles = 1;
+	} else {
+		c = pc->clk_rate;
+		c = c * duty_ns;
+		do_div(c, NSEC_PER_SEC);
+		duty_cycles = (unsigned long)c;
+	}
+
+	pm_runtime_get_sync(pc->chip.dev);
+
+	reg_val = readw(pc->mmio_base + ECCTL2);
+
+	/* Configure APWM mode & disable sync option */
+	reg_val |= ECCTL2_APWM_MODE | ECCTL2_SYNC_SEL_DISA;
+
+	writew(reg_val, pc->mmio_base + ECCTL2);
+
+	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+		/* Update active registers if not running */
+		writel(duty_cycles, pc->mmio_base + CAP2);
+		writel(period_cycles, pc->mmio_base + CAP1);
+	} else {
+		/*
+		 * Update shadow registers to configure period and
+		 * compare values. This helps current PWM period to
+		 * complete on reconfiguring
+		 */
+		writel(duty_cycles, pc->mmio_base + CAP4);
+		writel(period_cycles, pc->mmio_base + CAP3);
+	}
+
+	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+		reg_val = readw(pc->mmio_base + ECCTL2);
+		/* Disable APWM mode to put APWM output Low */
+		reg_val &= ~ECCTL2_APWM_MODE;
+		writew(reg_val, pc->mmio_base + ECCTL2);
+	}
+
+	pm_runtime_put_sync(pc->chip.dev);
+	return 0;
+}
+
+static int ecap_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
+		enum pwm_polarity polarity)
+{
+	struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
+	unsigned short reg_val;
+
+	pm_runtime_get_sync(pc->chip.dev);
+	reg_val = readw(pc->mmio_base + ECCTL2);
+	if (polarity == PWM_POLARITY_INVERSED)
+		/* Duty cycle defines LOW period of PWM */
+		reg_val |= ECCTL2_APWM_POL_LOW;
+	else
+		/* Duty cycle defines HIGH period of PWM */
+		reg_val &= ~ECCTL2_APWM_POL_LOW;
+
+	writew(reg_val, pc->mmio_base + ECCTL2);
+	pm_runtime_put_sync(pc->chip.dev);
+	return 0;
+}
+
+static int ecap_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
+	unsigned int reg_val;
+
+	/* Leave clock enabled on enabling PWM */
+	pm_runtime_get_sync(pc->chip.dev);
+
+	/*
+	 * Enable 'Free run Time stamp counter mode' to start counter
+	 * and  'APWM mode' to enable APWM output
+	 */
+	reg_val = readw(pc->mmio_base + ECCTL2);
+	reg_val |= ECCTL2_TSCTR_FREERUN | ECCTL2_APWM_MODE;
+	writew(reg_val, pc->mmio_base + ECCTL2);
+	return 0;
+}
+
+static void ecap_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
+	unsigned int reg_val;
+
+	/*
+	 * Disable 'Free run Time stamp counter mode' to stop counter
+	 * and 'APWM mode' to put APWM output to low
+	 */
+	reg_val = readw(pc->mmio_base + ECCTL2);
+	reg_val &= ~(ECCTL2_TSCTR_FREERUN | ECCTL2_APWM_MODE);
+	writew(reg_val, pc->mmio_base + ECCTL2);
+
+	/* Disable clock on PWM disable */
+	pm_runtime_put_sync(pc->chip.dev);
+}
+
+static void ecap_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+		dev_warn(chip->dev, "Removing PWM device without disabling\n");
+		pm_runtime_put_sync(chip->dev);
+	}
+}
+
+static const struct pwm_ops ecap_pwm_ops = {
+	.free		= ecap_pwm_free,
+	.config		= ecap_pwm_config,
+	.set_polarity	= ecap_pwm_set_polarity,
+	.enable		= ecap_pwm_enable,
+	.disable	= ecap_pwm_disable,
+	.owner		= THIS_MODULE,
+};
+
+static const struct of_device_id ecap_of_match[] = {
+	{ .compatible	= "ti,am33xx-ecap" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ecap_of_match);
+
+static int ecap_pwm_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *r;
+	struct clk *clk;
+	struct ecap_pwm_chip *pc;
+	u16 status;
+	struct pinctrl *pinctrl;
+
+	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+	if (IS_ERR(pinctrl))
+		dev_warn(&pdev->dev, "unable to select pin group\n");
+
+	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
+	if (!pc) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	clk = devm_clk_get(&pdev->dev, "fck");
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	pc->clk_rate = clk_get_rate(clk);
+	if (!pc->clk_rate) {
+		dev_err(&pdev->dev, "failed to get clock rate\n");
+		return -EINVAL;
+	}
+
+	pc->chip.dev = &pdev->dev;
+	pc->chip.ops = &ecap_pwm_ops;
+	pc->chip.of_xlate = of_pwm_xlate_with_flags;
+	pc->chip.of_pwm_n_cells = 3;
+	pc->chip.base = -1;
+	pc->chip.npwm = 1;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pc->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(pc->mmio_base))
+		return PTR_ERR(pc->mmio_base);
+
+	ret = pwmchip_add(&pc->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	status = pwmss_submodule_state_change(pdev->dev.parent,
+			PWMSS_ECAPCLK_EN);
+	if (!(status & PWMSS_ECAPCLK_EN_ACK)) {
+		dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
+		ret = -EINVAL;
+		goto pwmss_clk_failure;
+	}
+
+	pm_runtime_put_sync(&pdev->dev);
+
+	platform_set_drvdata(pdev, pc);
+	return 0;
+
+pwmss_clk_failure:
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pwmchip_remove(&pc->chip);
+	return ret;
+}
+
+static int ecap_pwm_remove(struct platform_device *pdev)
+{
+	struct ecap_pwm_chip *pc = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	/*
+	 * Due to hardware misbehaviour, acknowledge of the stop_req
+	 * is missing. Hence checking of the status bit skipped.
+	 */
+	pwmss_submodule_state_change(pdev->dev.parent, PWMSS_ECAPCLK_STOP_REQ);
+	pm_runtime_put_sync(&pdev->dev);
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	return pwmchip_remove(&pc->chip);
+}
+
+static void ecap_pwm_save_context(struct ecap_pwm_chip *pc)
+{
+	pm_runtime_get_sync(pc->chip.dev);
+	pc->ctx.ecctl2 = readw(pc->mmio_base + ECCTL2);
+	pc->ctx.cap4 = readl(pc->mmio_base + CAP4);
+	pc->ctx.cap3 = readl(pc->mmio_base + CAP3);
+	pm_runtime_put_sync(pc->chip.dev);
+}
+
+static void ecap_pwm_restore_context(struct ecap_pwm_chip *pc)
+{
+	writel(pc->ctx.cap3, pc->mmio_base + CAP3);
+	writel(pc->ctx.cap4, pc->mmio_base + CAP4);
+	writew(pc->ctx.ecctl2, pc->mmio_base + ECCTL2);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ecap_pwm_suspend(struct device *dev)
+{
+	struct ecap_pwm_chip *pc = dev_get_drvdata(dev);
+	struct pwm_device *pwm = pc->chip.pwms;
+
+	ecap_pwm_save_context(pc);
+
+	/* Disable explicitly if PWM is running */
+	if (test_bit(PWMF_ENABLED, &pwm->flags))
+		pm_runtime_put_sync(dev);
+
+	return 0;
+}
+
+static int ecap_pwm_resume(struct device *dev)
+{
+	struct ecap_pwm_chip *pc = dev_get_drvdata(dev);
+	struct pwm_device *pwm = pc->chip.pwms;
+
+	/* Enable explicitly if PWM was running */
+	if (test_bit(PWMF_ENABLED, &pwm->flags))
+		pm_runtime_get_sync(dev);
+
+	ecap_pwm_restore_context(pc);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(ecap_pwm_pm_ops, ecap_pwm_suspend, ecap_pwm_resume);
+
+static struct platform_driver ecap_pwm_driver = {
+	.driver = {
+		.name	= "ecap",
+		.owner	= THIS_MODULE,
+		.of_match_table = ecap_of_match,
+		.pm	= &ecap_pwm_pm_ops,
+	},
+	.probe = ecap_pwm_probe,
+	.remove = ecap_pwm_remove,
+};
+
+module_platform_driver(ecap_pwm_driver);
+
+MODULE_DESCRIPTION("ECAP PWM driver");
+MODULE_AUTHOR("Texas Instruments");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-tiehrpwm.c

@@ -0,0 +1,613 @@
+/*
+ * EHRPWM PWM driver
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc. - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+
+#include "pwm-tipwmss.h"
+
+/* EHRPWM registers and bits definitions */
+
+/* Time base module registers */
+#define TBCTL			0x00
+#define TBPRD			0x0A
+
+#define TBCTL_RUN_MASK		(BIT(15) | BIT(14))
+#define TBCTL_STOP_NEXT		0
+#define TBCTL_STOP_ON_CYCLE	BIT(14)
+#define TBCTL_FREE_RUN		(BIT(15) | BIT(14))
+#define TBCTL_PRDLD_MASK	BIT(3)
+#define TBCTL_PRDLD_SHDW	0
+#define TBCTL_PRDLD_IMDT	BIT(3)
+#define TBCTL_CLKDIV_MASK	(BIT(12) | BIT(11) | BIT(10) | BIT(9) | \
+				BIT(8) | BIT(7))
+#define TBCTL_CTRMODE_MASK	(BIT(1) | BIT(0))
+#define TBCTL_CTRMODE_UP	0
+#define TBCTL_CTRMODE_DOWN	BIT(0)
+#define TBCTL_CTRMODE_UPDOWN	BIT(1)
+#define TBCTL_CTRMODE_FREEZE	(BIT(1) | BIT(0))
+
+#define TBCTL_HSPCLKDIV_SHIFT	7
+#define TBCTL_CLKDIV_SHIFT	10
+
+#define CLKDIV_MAX		7
+#define HSPCLKDIV_MAX		7
+#define PERIOD_MAX		0xFFFF
+
+/* compare module registers */
+#define CMPA			0x12
+#define CMPB			0x14
+
+/* Action qualifier module registers */
+#define AQCTLA			0x16
+#define AQCTLB			0x18
+#define AQSFRC			0x1A
+#define AQCSFRC			0x1C
+
+#define AQCTL_CBU_MASK		(BIT(9) | BIT(8))
+#define AQCTL_CBU_FRCLOW	BIT(8)
+#define AQCTL_CBU_FRCHIGH	BIT(9)
+#define AQCTL_CBU_FRCTOGGLE	(BIT(9) | BIT(8))
+#define AQCTL_CAU_MASK		(BIT(5) | BIT(4))
+#define AQCTL_CAU_FRCLOW	BIT(4)
+#define AQCTL_CAU_FRCHIGH	BIT(5)
+#define AQCTL_CAU_FRCTOGGLE	(BIT(5) | BIT(4))
+#define AQCTL_PRD_MASK		(BIT(3) | BIT(2))
+#define AQCTL_PRD_FRCLOW	BIT(2)
+#define AQCTL_PRD_FRCHIGH	BIT(3)
+#define AQCTL_PRD_FRCTOGGLE	(BIT(3) | BIT(2))
+#define AQCTL_ZRO_MASK		(BIT(1) | BIT(0))
+#define AQCTL_ZRO_FRCLOW	BIT(0)
+#define AQCTL_ZRO_FRCHIGH	BIT(1)
+#define AQCTL_ZRO_FRCTOGGLE	(BIT(1) | BIT(0))
+
+#define AQCTL_CHANA_POLNORMAL	(AQCTL_CAU_FRCLOW | AQCTL_PRD_FRCHIGH | \
+				AQCTL_ZRO_FRCHIGH)
+#define AQCTL_CHANA_POLINVERSED	(AQCTL_CAU_FRCHIGH | AQCTL_PRD_FRCLOW | \
+				AQCTL_ZRO_FRCLOW)
+#define AQCTL_CHANB_POLNORMAL	(AQCTL_CBU_FRCLOW | AQCTL_PRD_FRCHIGH | \
+				AQCTL_ZRO_FRCHIGH)
+#define AQCTL_CHANB_POLINVERSED	(AQCTL_CBU_FRCHIGH | AQCTL_PRD_FRCLOW | \
+				AQCTL_ZRO_FRCLOW)
+
+#define AQSFRC_RLDCSF_MASK	(BIT(7) | BIT(6))
+#define AQSFRC_RLDCSF_ZRO	0
+#define AQSFRC_RLDCSF_PRD	BIT(6)
+#define AQSFRC_RLDCSF_ZROPRD	BIT(7)
+#define AQSFRC_RLDCSF_IMDT	(BIT(7) | BIT(6))
+
+#define AQCSFRC_CSFB_MASK	(BIT(3) | BIT(2))
+#define AQCSFRC_CSFB_FRCDIS	0
+#define AQCSFRC_CSFB_FRCLOW	BIT(2)
+#define AQCSFRC_CSFB_FRCHIGH	BIT(3)
+#define AQCSFRC_CSFB_DISSWFRC	(BIT(3) | BIT(2))
+#define AQCSFRC_CSFA_MASK	(BIT(1) | BIT(0))
+#define AQCSFRC_CSFA_FRCDIS	0
+#define AQCSFRC_CSFA_FRCLOW	BIT(0)
+#define AQCSFRC_CSFA_FRCHIGH	BIT(1)
+#define AQCSFRC_CSFA_DISSWFRC	(BIT(1) | BIT(0))
+
+#define NUM_PWM_CHANNEL		2	/* EHRPWM channels */
+
+struct ehrpwm_context {
+	u16 tbctl;
+	u16 tbprd;
+	u16 cmpa;
+	u16 cmpb;
+	u16 aqctla;
+	u16 aqctlb;
+	u16 aqsfrc;
+	u16 aqcsfrc;
+};
+
+struct ehrpwm_pwm_chip {
+	struct pwm_chip	chip;
+	unsigned int	clk_rate;
+	void __iomem	*mmio_base;
+	unsigned long period_cycles[NUM_PWM_CHANNEL];
+	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
+	struct	clk	*tbclk;
+	struct ehrpwm_context ctx;
+};
+
+static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct ehrpwm_pwm_chip, chip);
+}
+
+static u16 ehrpwm_read(void *base, int offset)
+{
+	return readw(base + offset);
+}
+
+static void ehrpwm_write(void *base, int offset, unsigned int val)
+{
+	writew(val & 0xFFFF, base + offset);
+}
+
+static void ehrpwm_modify(void *base, int offset,
+		unsigned short mask, unsigned short val)
+{
+	unsigned short regval;
+
+	regval = readw(base + offset);
+	regval &= ~mask;
+	regval |= val & mask;
+	writew(regval, base + offset);
+}
+
+/**
+ * set_prescale_div -	Set up the prescaler divider function
+ * @rqst_prescaler:	prescaler value min
+ * @prescale_div:	prescaler value set
+ * @tb_clk_div:		Time Base Control prescaler bits
+ */
+static int set_prescale_div(unsigned long rqst_prescaler,
+		unsigned short *prescale_div, unsigned short *tb_clk_div)
+{
+	unsigned int clkdiv, hspclkdiv;
+
+	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) {
+		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) {
+
+			/*
+			 * calculations for prescaler value :
+			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER.
+			 * HSPCLKDIVIDER =  2 ** hspclkdiv
+			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR*
+			 *		(2 * clkdiv),	if clkdiv != 0
+			 *
+			 * Configure prescale_div value such that period
+			 * register value is less than 65535.
+			 */
+
+			*prescale_div = (1 << clkdiv) *
+					(hspclkdiv ? (hspclkdiv * 2) : 1);
+			if (*prescale_div > rqst_prescaler) {
+				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) |
+					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT);
+				return 0;
+			}
+		}
+	}
+	return 1;
+}
+
+static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
+{
+	int aqctl_reg;
+	unsigned short aqctl_val, aqctl_mask;
+
+	/*
+	 * Configure PWM output to HIGH/LOW level on counter
+	 * reaches compare register value and LOW/HIGH level
+	 * on counter value reaches period register value and
+	 * zero value on counter
+	 */
+	if (chan == 1) {
+		aqctl_reg = AQCTLB;
+		aqctl_mask = AQCTL_CBU_MASK;
+
+		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
+			aqctl_val = AQCTL_CHANB_POLINVERSED;
+		else
+			aqctl_val = AQCTL_CHANB_POLNORMAL;
+	} else {
+		aqctl_reg = AQCTLA;
+		aqctl_mask = AQCTL_CAU_MASK;
+
+		if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
+			aqctl_val = AQCTL_CHANA_POLINVERSED;
+		else
+			aqctl_val = AQCTL_CHANA_POLNORMAL;
+	}
+
+	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
+	ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
+}
+
+/*
+ * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE
+ * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE
+ */
+static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
+{
+	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+	unsigned long long c;
+	unsigned long period_cycles, duty_cycles;
+	unsigned short ps_divval, tb_divval;
+	int i, cmp_reg;
+
+	if (period_ns > NSEC_PER_SEC)
+		return -ERANGE;
+
+	c = pc->clk_rate;
+	c = c * period_ns;
+	do_div(c, NSEC_PER_SEC);
+	period_cycles = (unsigned long)c;
+
+	if (period_cycles < 1) {
+		period_cycles = 1;
+		duty_cycles = 1;
+	} else {
+		c = pc->clk_rate;
+		c = c * duty_ns;
+		do_div(c, NSEC_PER_SEC);
+		duty_cycles = (unsigned long)c;
+	}
+
+	/*
+	 * Period values should be same for multiple PWM channels as IP uses
+	 * same period register for multiple channels.
+	 */
+	for (i = 0; i < NUM_PWM_CHANNEL; i++) {
+		if (pc->period_cycles[i] &&
+				(pc->period_cycles[i] != period_cycles)) {
+			/*
+			 * Allow channel to reconfigure period if no other
+			 * channels being configured.
+			 */
+			if (i == pwm->hwpwm)
+				continue;
+
+			dev_err(chip->dev, "Period value conflicts with channel %d\n",
+					i);
+			return -EINVAL;
+		}
+	}
+
+	pc->period_cycles[pwm->hwpwm] = period_cycles;
+
+	/* Configure clock prescaler to support Low frequency PWM wave */
+	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
+				&tb_divval)) {
+		dev_err(chip->dev, "Unsupported values\n");
+		return -EINVAL;
+	}
+
+	pm_runtime_get_sync(chip->dev);
+
+	/* Update clock prescaler values */
+	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CLKDIV_MASK, tb_divval);
+
+	/* Update period & duty cycle with presacler division */
+	period_cycles = period_cycles / ps_divval;
+	duty_cycles = duty_cycles / ps_divval;
+
+	/* Configure shadow loading on Period register */
+	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_PRDLD_MASK, TBCTL_PRDLD_SHDW);
+
+	ehrpwm_write(pc->mmio_base, TBPRD, period_cycles);
+
+	/* Configure ehrpwm counter for up-count mode */
+	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
+			TBCTL_CTRMODE_UP);
+
+	if (pwm->hwpwm == 1)
+		/* Channel 1 configured with compare B register */
+		cmp_reg = CMPB;
+	else
+		/* Channel 0 configured with compare A register */
+		cmp_reg = CMPA;
+
+	ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
+
+	pm_runtime_put_sync(chip->dev);
+	return 0;
+}
+
+static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
+		struct pwm_device *pwm,	enum pwm_polarity polarity)
+{
+	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+
+	/* Configuration of polarity in hardware delayed, do at enable */
+	pc->polarity[pwm->hwpwm] = polarity;
+	return 0;
+}
+
+static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+	unsigned short aqcsfrc_val, aqcsfrc_mask;
+	int ret;
+
+	/* Leave clock enabled on enabling PWM */
+	pm_runtime_get_sync(chip->dev);
+
+	/* Disabling Action Qualifier on PWM output */
+	if (pwm->hwpwm) {
+		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS;
+		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
+	} else {
+		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS;
+		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
+	}
+
+	/* Changes to shadow mode */
+	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
+			AQSFRC_RLDCSF_ZRO);
+
+	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
+
+	/* Channels polarity can be configured from action qualifier module */
+	configure_polarity(pc, pwm->hwpwm);
+
+	/* Enable TBCLK before enabling PWM device */
+	ret = clk_prepare_enable(pc->tbclk);
+	if (ret) {
+		pr_err("Failed to enable TBCLK for %s\n",
+				dev_name(pc->chip.dev));
+		return ret;
+	}
+
+	/* Enable time counter for free_run */
+	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN);
+	return 0;
+}
+
+static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+	unsigned short aqcsfrc_val, aqcsfrc_mask;
+
+	/* Action Qualifier puts PWM output low forcefully */
+	if (pwm->hwpwm) {
+		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW;
+		aqcsfrc_mask = AQCSFRC_CSFB_MASK;
+	} else {
+		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW;
+		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
+	}
+
+	/*
+	 * Changes to immediate action on Action Qualifier. This puts
+	 * Action Qualifier control on PWM output from next TBCLK
+	 */
+	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
+			AQSFRC_RLDCSF_IMDT);
+
+	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
+
+	/* Disabling TBCLK on PWM disable */
+	clk_disable_unprepare(pc->tbclk);
+
+	/* Stop Time base counter */
+	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_STOP_NEXT);
+
+	/* Disable clock on PWM disable */
+	pm_runtime_put_sync(chip->dev);
+}
+
+static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+
+	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+		dev_warn(chip->dev, "Removing PWM device without disabling\n");
+		pm_runtime_put_sync(chip->dev);
+	}
+
+	/* set period value to zero on free */
+	pc->period_cycles[pwm->hwpwm] = 0;
+}
+
+static const struct pwm_ops ehrpwm_pwm_ops = {
+	.free		= ehrpwm_pwm_free,
+	.config		= ehrpwm_pwm_config,
+	.set_polarity	= ehrpwm_pwm_set_polarity,
+	.enable		= ehrpwm_pwm_enable,
+	.disable	= ehrpwm_pwm_disable,
+	.owner		= THIS_MODULE,
+};
+
+static const struct of_device_id ehrpwm_of_match[] = {
+	{ .compatible	= "ti,am33xx-ehrpwm" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
+
+static int ehrpwm_pwm_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *r;
+	struct clk *clk;
+	struct ehrpwm_pwm_chip *pc;
+	u16 status;
+	struct pinctrl *pinctrl;
+
+	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+	if (IS_ERR(pinctrl))
+		dev_warn(&pdev->dev, "unable to select pin group\n");
+
+	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
+	if (!pc) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	clk = devm_clk_get(&pdev->dev, "fck");
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	pc->clk_rate = clk_get_rate(clk);
+	if (!pc->clk_rate) {
+		dev_err(&pdev->dev, "failed to get clock rate\n");
+		return -EINVAL;
+	}
+
+	pc->chip.dev = &pdev->dev;
+	pc->chip.ops = &ehrpwm_pwm_ops;
+	pc->chip.of_xlate = of_pwm_xlate_with_flags;
+	pc->chip.of_pwm_n_cells = 3;
+	pc->chip.base = -1;
+	pc->chip.npwm = NUM_PWM_CHANNEL;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pc->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(pc->mmio_base))
+		return PTR_ERR(pc->mmio_base);
+
+	/* Acquire tbclk for Time Base EHRPWM submodule */
+	pc->tbclk = devm_clk_get(&pdev->dev, "tbclk");
+	if (IS_ERR(pc->tbclk)) {
+		dev_err(&pdev->dev, "Failed to get tbclk\n");
+		return PTR_ERR(pc->tbclk);
+	}
+
+	ret = pwmchip_add(&pc->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		return ret;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	status = pwmss_submodule_state_change(pdev->dev.parent,
+			PWMSS_EPWMCLK_EN);
+	if (!(status & PWMSS_EPWMCLK_EN_ACK)) {
+		dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
+		ret = -EINVAL;
+		goto pwmss_clk_failure;
+	}
+
+	pm_runtime_put_sync(&pdev->dev);
+
+	platform_set_drvdata(pdev, pc);
+	return 0;
+
+pwmss_clk_failure:
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pwmchip_remove(&pc->chip);
+	return ret;
+}
+
+static int ehrpwm_pwm_remove(struct platform_device *pdev)
+{
+	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	/*
+	 * Due to hardware misbehaviour, acknowledge of the stop_req
+	 * is missing. Hence checking of the status bit skipped.
+	 */
+	pwmss_submodule_state_change(pdev->dev.parent, PWMSS_EPWMCLK_STOP_REQ);
+	pm_runtime_put_sync(&pdev->dev);
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	return pwmchip_remove(&pc->chip);
+}
+
+static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
+{
+	pm_runtime_get_sync(pc->chip.dev);
+	pc->ctx.tbctl = ehrpwm_read(pc->mmio_base, TBCTL);
+	pc->ctx.tbprd = ehrpwm_read(pc->mmio_base, TBPRD);
+	pc->ctx.cmpa = ehrpwm_read(pc->mmio_base, CMPA);
+	pc->ctx.cmpb = ehrpwm_read(pc->mmio_base, CMPB);
+	pc->ctx.aqctla = ehrpwm_read(pc->mmio_base, AQCTLA);
+	pc->ctx.aqctlb = ehrpwm_read(pc->mmio_base, AQCTLB);
+	pc->ctx.aqsfrc = ehrpwm_read(pc->mmio_base, AQSFRC);
+	pc->ctx.aqcsfrc = ehrpwm_read(pc->mmio_base, AQCSFRC);
+	pm_runtime_put_sync(pc->chip.dev);
+}
+
+static void ehrpwm_pwm_restore_context(struct ehrpwm_pwm_chip *pc)
+{
+	ehrpwm_write(pc->mmio_base, TBPRD, pc->ctx.tbprd);
+	ehrpwm_write(pc->mmio_base, CMPA, pc->ctx.cmpa);
+	ehrpwm_write(pc->mmio_base, CMPB, pc->ctx.cmpb);
+	ehrpwm_write(pc->mmio_base, AQCTLA, pc->ctx.aqctla);
+	ehrpwm_write(pc->mmio_base, AQCTLB, pc->ctx.aqctlb);
+	ehrpwm_write(pc->mmio_base, AQSFRC, pc->ctx.aqsfrc);
+	ehrpwm_write(pc->mmio_base, AQCSFRC, pc->ctx.aqcsfrc);
+	ehrpwm_write(pc->mmio_base, TBCTL, pc->ctx.tbctl);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ehrpwm_pwm_suspend(struct device *dev)
+{
+	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
+	int i;
+
+	ehrpwm_pwm_save_context(pc);
+	for (i = 0; i < pc->chip.npwm; i++) {
+		struct pwm_device *pwm = &pc->chip.pwms[i];
+
+		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+			continue;
+
+		/* Disable explicitly if PWM is running */
+		pm_runtime_put_sync(dev);
+	}
+	return 0;
+}
+
+static int ehrpwm_pwm_resume(struct device *dev)
+{
+	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < pc->chip.npwm; i++) {
+		struct pwm_device *pwm = &pc->chip.pwms[i];
+
+		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+			continue;
+
+		/* Enable explicitly if PWM was running */
+		pm_runtime_get_sync(dev);
+	}
+	ehrpwm_pwm_restore_context(pc);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
+		ehrpwm_pwm_resume);
+
+static struct platform_driver ehrpwm_pwm_driver = {
+	.driver = {
+		.name	= "ehrpwm",
+		.owner	= THIS_MODULE,
+		.of_match_table = ehrpwm_of_match,
+		.pm	= &ehrpwm_pwm_pm_ops,
+	},
+	.probe = ehrpwm_pwm_probe,
+	.remove = ehrpwm_pwm_remove,
+};
+
+module_platform_driver(ehrpwm_pwm_driver);
+
+MODULE_DESCRIPTION("EHRPWM PWM driver");
+MODULE_AUTHOR("Texas Instruments");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-tipwmss.c

@@ -0,0 +1,136 @@
+/*
+ * TI PWM Subsystem driver
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+
+#include "pwm-tipwmss.h"
+
+#define PWMSS_CLKCONFIG		0x8	/* Clock gating reg */
+#define PWMSS_CLKSTATUS		0xc	/* Clock gating status reg */
+
+struct pwmss_info {
+	void __iomem	*mmio_base;
+	struct mutex	pwmss_lock;
+	u16		pwmss_clkconfig;
+};
+
+u16 pwmss_submodule_state_change(struct device *dev, int set)
+{
+	struct pwmss_info *info = dev_get_drvdata(dev);
+	u16 val;
+
+	mutex_lock(&info->pwmss_lock);
+	val = readw(info->mmio_base + PWMSS_CLKCONFIG);
+	val |= set;
+	writew(val , info->mmio_base + PWMSS_CLKCONFIG);
+	mutex_unlock(&info->pwmss_lock);
+
+	return readw(info->mmio_base + PWMSS_CLKSTATUS);
+}
+EXPORT_SYMBOL(pwmss_submodule_state_change);
+
+static const struct of_device_id pwmss_of_match[] = {
+	{ .compatible	= "ti,am33xx-pwmss" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, pwmss_of_match);
+
+static int pwmss_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *r;
+	struct pwmss_info *info;
+	struct device_node *node = pdev->dev.of_node;
+
+	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	mutex_init(&info->pwmss_lock);
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	info->mmio_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(info->mmio_base))
+		return PTR_ERR(info->mmio_base);
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+	platform_set_drvdata(pdev, info);
+
+	/* Populate all the child nodes here... */
+	ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
+	if (ret)
+		dev_err(&pdev->dev, "no child node found\n");
+
+	return ret;
+}
+
+static int pwmss_remove(struct platform_device *pdev)
+{
+	struct pwmss_info *info = platform_get_drvdata(pdev);
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	mutex_destroy(&info->pwmss_lock);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int pwmss_suspend(struct device *dev)
+{
+	struct pwmss_info *info = dev_get_drvdata(dev);
+
+	info->pwmss_clkconfig = readw(info->mmio_base + PWMSS_CLKCONFIG);
+	pm_runtime_put_sync(dev);
+	return 0;
+}
+
+static int pwmss_resume(struct device *dev)
+{
+	struct pwmss_info *info = dev_get_drvdata(dev);
+
+	pm_runtime_get_sync(dev);
+	writew(info->pwmss_clkconfig, info->mmio_base + PWMSS_CLKCONFIG);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pwmss_pm_ops, pwmss_suspend, pwmss_resume);
+
+static struct platform_driver pwmss_driver = {
+	.driver	= {
+		.name	= "pwmss",
+		.owner	= THIS_MODULE,
+		.pm	= &pwmss_pm_ops,
+		.of_match_table	= pwmss_of_match,
+	},
+	.probe	= pwmss_probe,
+	.remove	= pwmss_remove,
+};
+
+module_platform_driver(pwmss_driver);
+
+MODULE_DESCRIPTION("PWM Subsystem driver");
+MODULE_AUTHOR("Texas Instruments");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-tipwmss.h

@@ -0,0 +1,39 @@
+/*
+ * TI PWM Subsystem driver
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __TIPWMSS_H
+#define __TIPWMSS_H
+
+/* PWM substem clock gating */
+#define PWMSS_ECAPCLK_EN	BIT(0)
+#define PWMSS_ECAPCLK_STOP_REQ	BIT(1)
+#define PWMSS_EPWMCLK_EN	BIT(8)
+#define PWMSS_EPWMCLK_STOP_REQ	BIT(9)
+
+#define PWMSS_ECAPCLK_EN_ACK	BIT(0)
+#define PWMSS_EPWMCLK_EN_ACK	BIT(8)
+
+#ifdef CONFIG_PWM_TIPWMSS
+extern u16 pwmss_submodule_state_change(struct device *dev, int set);
+#else
+static inline u16 pwmss_submodule_state_change(struct device *dev, int set)
+{
+	/* return success status value */
+	return 0xFFFF;
+}
+#endif
+#endif	/* __TIPWMSS_H */

drivers/pwm/pwm-twl-led.c

@@ -0,0 +1,347 @@
+/*
+ * Driver for TWL4030/6030 Pulse Width Modulator used as LED driver
+ *
+ * Copyright (C) 2012 Texas Instruments
+ * Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
+ *
+ * This driver is a complete rewrite of the former pwm-twl6030.c authorded by:
+ * Hemanth V <hemanthv@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/i2c/twl.h>
+#include <linux/slab.h>
+
+/*
+ * This driver handles the PWM driven LED terminals of TWL4030 and TWL6030.
+ * To generate the signal on TWL4030:
+ *  - LEDA uses PWMA
+ *  - LEDB uses PWMB
+ * TWL6030 has one LED pin with dedicated LEDPWM
+ */
+
+#define TWL4030_LED_MAX		0x7f
+#define TWL6030_LED_MAX		0xff
+
+/* Registers, bits and macro for TWL4030 */
+#define TWL4030_LEDEN_REG	0x00
+#define TWL4030_PWMA_REG	0x01
+
+#define TWL4030_LEDXON		(1 << 0)
+#define TWL4030_LEDXPWM		(1 << 4)
+#define TWL4030_LED_PINS	(TWL4030_LEDXON | TWL4030_LEDXPWM)
+#define TWL4030_LED_TOGGLE(led, x)	((x) << (led))
+
+/* Register, bits and macro for TWL6030 */
+#define TWL6030_LED_PWM_CTRL1	0xf4
+#define TWL6030_LED_PWM_CTRL2	0xf5
+
+#define TWL6040_LED_MODE_HW	0x00
+#define TWL6040_LED_MODE_ON	0x01
+#define TWL6040_LED_MODE_OFF	0x02
+#define TWL6040_LED_MODE_MASK	0x03
+
+struct twl_pwmled_chip {
+	struct pwm_chip chip;
+	struct mutex mutex;
+};
+
+static inline struct twl_pwmled_chip *to_twl(struct pwm_chip *chip)
+{
+	return container_of(chip, struct twl_pwmled_chip, chip);
+}
+
+static int twl4030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	int duty_cycle = DIV_ROUND_UP(duty_ns * TWL4030_LED_MAX, period_ns) + 1;
+	u8 pwm_config[2] = { 1, 0 };
+	int base, ret;
+
+	/*
+	 * To configure the duty period:
+	 * On-cycle is set to 1 (the minimum allowed value)
+	 * The off time of 0 is not configurable, so the mapping is:
+	 * 0 -> off cycle = 2,
+	 * 1 -> off cycle = 2,
+	 * 2 -> off cycle = 3,
+	 * 126 - > off cycle 127,
+	 * 127 - > off cycle 1
+	 * When on cycle == off cycle the PWM will be always on
+	 */
+	if (duty_cycle == 1)
+		duty_cycle = 2;
+	else if (duty_cycle > TWL4030_LED_MAX)
+		duty_cycle = 1;
+
+	base = pwm->hwpwm * 2 + TWL4030_PWMA_REG;
+
+	pwm_config[1] = duty_cycle;
+
+	ret = twl_i2c_write(TWL4030_MODULE_LED, pwm_config, base, 2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label);
+
+	return ret;
+}
+
+static int twl4030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label);
+		goto out;
+	}
+
+	val |= TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl4030_pwmled_disable(struct pwm_chip *chip,
+				   struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static int twl6030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	int duty_cycle = (duty_ns * TWL6030_LED_MAX) / period_ns;
+	u8 on_time;
+	int ret;
+
+	on_time = duty_cycle & 0xff;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, on_time,
+			       TWL6030_LED_PWM_CTRL1);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label);
+
+	return ret;
+}
+
+static int twl6030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n",
+			pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL6040_LED_MODE_MASK;
+	val |= TWL6040_LED_MODE_ON;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl6030_pwmled_disable(struct pwm_chip *chip,
+				   struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n",
+			pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL6040_LED_MODE_MASK;
+	val |= TWL6040_LED_MODE_OFF;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static int twl6030_pwmled_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n",
+			pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL6040_LED_MODE_MASK;
+	val |= TWL6040_LED_MODE_OFF;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl6030_pwmled_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwmled_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n",
+			pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL6040_LED_MODE_MASK;
+	val |= TWL6040_LED_MODE_HW;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static const struct pwm_ops twl4030_pwmled_ops = {
+	.enable = twl4030_pwmled_enable,
+	.disable = twl4030_pwmled_disable,
+	.config = twl4030_pwmled_config,
+	.owner = THIS_MODULE,
+};
+
+static const struct pwm_ops twl6030_pwmled_ops = {
+	.enable = twl6030_pwmled_enable,
+	.disable = twl6030_pwmled_disable,
+	.config = twl6030_pwmled_config,
+	.request = twl6030_pwmled_request,
+	.free = twl6030_pwmled_free,
+	.owner = THIS_MODULE,
+};
+
+static int twl_pwmled_probe(struct platform_device *pdev)
+{
+	struct twl_pwmled_chip *twl;
+	int ret;
+
+	twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL);
+	if (!twl)
+		return -ENOMEM;
+
+	if (twl_class_is_4030()) {
+		twl->chip.ops = &twl4030_pwmled_ops;
+		twl->chip.npwm = 2;
+	} else {
+		twl->chip.ops = &twl6030_pwmled_ops;
+		twl->chip.npwm = 1;
+	}
+
+	twl->chip.dev = &pdev->dev;
+	twl->chip.base = -1;
+	twl->chip.can_sleep = true;
+
+	mutex_init(&twl->mutex);
+
+	ret = pwmchip_add(&twl->chip);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, twl);
+
+	return 0;
+}
+
+static int twl_pwmled_remove(struct platform_device *pdev)
+{
+	struct twl_pwmled_chip *twl = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&twl->chip);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id twl_pwmled_of_match[] = {
+	{ .compatible = "ti,twl4030-pwmled" },
+	{ .compatible = "ti,twl6030-pwmled" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, twl_pwmled_of_match);
+#endif
+
+static struct platform_driver twl_pwmled_driver = {
+	.driver = {
+		.name = "twl-pwmled",
+		.of_match_table = of_match_ptr(twl_pwmled_of_match),
+	},
+	.probe = twl_pwmled_probe,
+	.remove = twl_pwmled_remove,
+};
+module_platform_driver(twl_pwmled_driver);
+
+MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
+MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030 LED outputs");
+MODULE_ALIAS("platform:twl-pwmled");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-twl.c

@@ -0,0 +1,359 @@
+/*
+ * Driver for TWL4030/6030 Generic Pulse Width Modulator
+ *
+ * Copyright (C) 2012 Texas Instruments
+ * Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/i2c/twl.h>
+#include <linux/slab.h>
+
+/*
+ * This driver handles the PWMs of TWL4030 and TWL6030.
+ * The TRM names for the PWMs on TWL4030 are: PWM0, PWM1
+ * TWL6030 also have two PWMs named in the TRM as PWM1, PWM2
+ */
+
+#define TWL_PWM_MAX		0x7f
+
+/* Registers, bits and macro for TWL4030 */
+#define TWL4030_GPBR1_REG	0x0c
+#define TWL4030_PMBR1_REG	0x0d
+
+/* GPBR1 register bits */
+#define TWL4030_PWMXCLK_ENABLE	(1 << 0)
+#define TWL4030_PWMX_ENABLE	(1 << 2)
+#define TWL4030_PWMX_BITS	(TWL4030_PWMX_ENABLE | TWL4030_PWMXCLK_ENABLE)
+#define TWL4030_PWM_TOGGLE(pwm, x)	((x) << (pwm))
+
+/* PMBR1 register bits */
+#define TWL4030_GPIO6_PWM0_MUTE_MASK		(0x03 << 2)
+#define TWL4030_GPIO6_PWM0_MUTE_PWM0		(0x01 << 2)
+#define TWL4030_GPIO7_VIBRASYNC_PWM1_MASK	(0x03 << 4)
+#define TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1	(0x03 << 4)
+
+/* Register, bits and macro for TWL6030 */
+#define TWL6030_TOGGLE3_REG	0x92
+
+#define TWL6030_PWMXR		(1 << 0)
+#define TWL6030_PWMXS		(1 << 1)
+#define TWL6030_PWMXEN		(1 << 2)
+#define TWL6030_PWM_TOGGLE(pwm, x)	((x) << (pwm * 3))
+
+struct twl_pwm_chip {
+	struct pwm_chip chip;
+	struct mutex mutex;
+	u8 twl6030_toggle3;
+	u8 twl4030_pwm_mux;
+};
+
+static inline struct twl_pwm_chip *to_twl(struct pwm_chip *chip)
+{
+	return container_of(chip, struct twl_pwm_chip, chip);
+}
+
+static int twl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	int duty_cycle = DIV_ROUND_UP(duty_ns * TWL_PWM_MAX, period_ns) + 1;
+	u8 pwm_config[2] = { 1, 0 };
+	int base, ret;
+
+	/*
+	 * To configure the duty period:
+	 * On-cycle is set to 1 (the minimum allowed value)
+	 * The off time of 0 is not configurable, so the mapping is:
+	 * 0 -> off cycle = 2,
+	 * 1 -> off cycle = 2,
+	 * 2 -> off cycle = 3,
+	 * 126 - > off cycle 127,
+	 * 127 - > off cycle 1
+	 * When on cycle == off cycle the PWM will be always on
+	 */
+	if (duty_cycle == 1)
+		duty_cycle = 2;
+	else if (duty_cycle > TWL_PWM_MAX)
+		duty_cycle = 1;
+
+	base = pwm->hwpwm * 3;
+
+	pwm_config[1] = duty_cycle;
+
+	ret = twl_i2c_write(TWL_MODULE_PWM, pwm_config, base, 2);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label);
+
+	return ret;
+}
+
+static int twl4030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label);
+		goto out;
+	}
+
+	val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
+
+	val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl4030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label);
+		goto out;
+	}
+
+	val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
+
+	val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static int twl4030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val, mask, bits;
+
+	if (pwm->hwpwm == 1) {
+		mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
+		bits = TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1;
+	} else {
+		mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
+		bits = TWL4030_GPIO6_PWM0_MUTE_PWM0;
+	}
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label);
+		goto out;
+	}
+
+	/* Save the current MUX configuration for the PWM */
+	twl->twl4030_pwm_mux &= ~mask;
+	twl->twl4030_pwm_mux |= (val & mask);
+
+	/* Select PWM functionality */
+	val &= ~mask;
+	val |= bits;
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val, mask;
+
+	if (pwm->hwpwm == 1)
+		mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
+	else
+		mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
+
+	mutex_lock(&twl->mutex);
+	ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label);
+		goto out;
+	}
+
+	/* Restore the MUX configuration for the PWM */
+	val &= ~mask;
+	val |= (twl->twl4030_pwm_mux & mask);
+
+	ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
+	if (ret < 0)
+		dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label);
+
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	val = twl->twl6030_toggle3;
+	val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
+	val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
+		goto out;
+	}
+
+	twl->twl6030_toggle3 = val;
+out:
+	mutex_unlock(&twl->mutex);
+	return ret;
+}
+
+static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct twl_pwm_chip *twl = to_twl(chip);
+	int ret;
+	u8 val;
+
+	mutex_lock(&twl->mutex);
+	val = twl->twl6030_toggle3;
+	val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
+	val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to read TOGGLE3\n", pwm->label);
+		goto out;
+	}
+
+	val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
+		goto out;
+	}
+
+	twl->twl6030_toggle3 = val;
+out:
+	mutex_unlock(&twl->mutex);
+}
+
+static const struct pwm_ops twl4030_pwm_ops = {
+	.config = twl_pwm_config,
+	.enable = twl4030_pwm_enable,
+	.disable = twl4030_pwm_disable,
+	.request = twl4030_pwm_request,
+	.free = twl4030_pwm_free,
+	.owner = THIS_MODULE,
+};
+
+static const struct pwm_ops twl6030_pwm_ops = {
+	.config = twl_pwm_config,
+	.enable = twl6030_pwm_enable,
+	.disable = twl6030_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static int twl_pwm_probe(struct platform_device *pdev)
+{
+	struct twl_pwm_chip *twl;
+	int ret;
+
+	twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL);
+	if (!twl)
+		return -ENOMEM;
+
+	if (twl_class_is_4030())
+		twl->chip.ops = &twl4030_pwm_ops;
+	else
+		twl->chip.ops = &twl6030_pwm_ops;
+
+	twl->chip.dev = &pdev->dev;
+	twl->chip.base = -1;
+	twl->chip.npwm = 2;
+	twl->chip.can_sleep = true;
+
+	mutex_init(&twl->mutex);
+
+	ret = pwmchip_add(&twl->chip);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, twl);
+
+	return 0;
+}
+
+static int twl_pwm_remove(struct platform_device *pdev)
+{
+	struct twl_pwm_chip *twl = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&twl->chip);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id twl_pwm_of_match[] = {
+	{ .compatible = "ti,twl4030-pwm" },
+	{ .compatible = "ti,twl6030-pwm" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, twl_pwm_of_match);
+#endif
+
+static struct platform_driver twl_pwm_driver = {
+	.driver = {
+		.name = "twl-pwm",
+		.of_match_table = of_match_ptr(twl_pwm_of_match),
+	},
+	.probe = twl_pwm_probe,
+	.remove = twl_pwm_remove,
+};
+module_platform_driver(twl_pwm_driver);
+
+MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
+MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030");
+MODULE_ALIAS("platform:twl-pwm");
+MODULE_LICENSE("GPL");

drivers/pwm/pwm-vt8500.c

@@ -0,0 +1,279 @@
+/*
+ * drivers/pwm/pwm-vt8500.c
+ *
+ * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+
+#include <asm/div64.h>
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+
+/*
+ * SoC architecture allocates register space for 4 PWMs but only
+ * 2 are currently implemented.
+ */
+#define VT8500_NR_PWMS	2
+
+#define REG_CTRL(pwm)		(((pwm) << 4) + 0x00)
+#define REG_SCALAR(pwm)		(((pwm) << 4) + 0x04)
+#define REG_PERIOD(pwm)		(((pwm) << 4) + 0x08)
+#define REG_DUTY(pwm)		(((pwm) << 4) + 0x0C)
+#define REG_STATUS		0x40
+
+#define CTRL_ENABLE		BIT(0)
+#define CTRL_INVERT		BIT(1)
+#define CTRL_AUTOLOAD		BIT(2)
+#define CTRL_STOP_IMM		BIT(3)
+#define CTRL_LOAD_PRESCALE	BIT(4)
+#define CTRL_LOAD_PERIOD	BIT(5)
+
+#define STATUS_CTRL_UPDATE	BIT(0)
+#define STATUS_SCALAR_UPDATE	BIT(1)
+#define STATUS_PERIOD_UPDATE	BIT(2)
+#define STATUS_DUTY_UPDATE	BIT(3)
+#define STATUS_ALL_UPDATE	0x0F
+
+struct vt8500_chip {
+	struct pwm_chip chip;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+#define to_vt8500_chip(chip)	container_of(chip, struct vt8500_chip, chip)
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+static inline void pwm_busy_wait(struct vt8500_chip *vt8500, int nr, u8 bitmask)
+{
+	int loops = msecs_to_loops(10);
+	u32 mask = bitmask << (nr << 8);
+
+	while ((readl(vt8500->base + REG_STATUS) & mask) && --loops)
+		cpu_relax();
+
+	if (unlikely(!loops))
+		dev_warn(vt8500->chip.dev, "Waiting for status bits 0x%x to clear timed out\n",
+			 mask);
+}
+
+static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
+{
+	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+	unsigned long long c;
+	unsigned long period_cycles, prescale, pv, dc;
+	int err;
+	u32 val;
+
+	err = clk_enable(vt8500->clk);
+	if (err < 0) {
+		dev_err(chip->dev, "failed to enable clock\n");
+		return err;
+	}
+
+	c = clk_get_rate(vt8500->clk);
+	c = c * period_ns;
+	do_div(c, 1000000000);
+	period_cycles = c;
+
+	if (period_cycles < 1)
+		period_cycles = 1;
+	prescale = (period_cycles - 1) / 4096;
+	pv = period_cycles / (prescale + 1) - 1;
+	if (pv > 4095)
+		pv = 4095;
+
+	if (prescale > 1023) {
+		clk_disable(vt8500->clk);
+		return -EINVAL;
+	}
+
+	c = (unsigned long long)pv * duty_ns;
+	do_div(c, period_ns);
+	dc = c;
+
+	writel(prescale, vt8500->base + REG_SCALAR(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_SCALAR_UPDATE);
+
+	writel(pv, vt8500->base + REG_PERIOD(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_PERIOD_UPDATE);
+
+	writel(dc, vt8500->base + REG_DUTY(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_DUTY_UPDATE);
+
+	val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
+	val |= CTRL_AUTOLOAD;
+	writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+
+	clk_disable(vt8500->clk);
+	return 0;
+}
+
+static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+	int err;
+	u32 val;
+
+	err = clk_enable(vt8500->clk);
+	if (err < 0) {
+		dev_err(chip->dev, "failed to enable clock\n");
+		return err;
+	}
+
+	val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
+	val |= CTRL_ENABLE;
+	writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+
+	return 0;
+}
+
+static void vt8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+	u32 val;
+
+	val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
+	val &= ~CTRL_ENABLE;
+	writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+
+	clk_disable(vt8500->clk);
+}
+
+static int vt8500_pwm_set_polarity(struct pwm_chip *chip,
+				   struct pwm_device *pwm,
+				   enum pwm_polarity polarity)
+{
+	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+	u32 val;
+
+	val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
+
+	if (polarity == PWM_POLARITY_INVERSED)
+		val |= CTRL_INVERT;
+	else
+		val &= ~CTRL_INVERT;
+
+	writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
+	pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+
+	return 0;
+}
+
+static struct pwm_ops vt8500_pwm_ops = {
+	.enable = vt8500_pwm_enable,
+	.disable = vt8500_pwm_disable,
+	.config = vt8500_pwm_config,
+	.set_polarity = vt8500_pwm_set_polarity,
+	.owner = THIS_MODULE,
+};
+
+static const struct of_device_id vt8500_pwm_dt_ids[] = {
+	{ .compatible = "via,vt8500-pwm", },
+	{ /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, vt8500_pwm_dt_ids);
+
+static int vt8500_pwm_probe(struct platform_device *pdev)
+{
+	struct vt8500_chip *chip;
+	struct resource *r;
+	struct device_node *np = pdev->dev.of_node;
+	int ret;
+
+	if (!np) {
+		dev_err(&pdev->dev, "invalid devicetree node\n");
+		return -EINVAL;
+	}
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (chip == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	chip->chip.dev = &pdev->dev;
+	chip->chip.ops = &vt8500_pwm_ops;
+	chip->chip.of_xlate = of_pwm_xlate_with_flags;
+	chip->chip.of_pwm_n_cells = 3;
+	chip->chip.base = -1;
+	chip->chip.npwm = VT8500_NR_PWMS;
+
+	chip->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(chip->clk)) {
+		dev_err(&pdev->dev, "clock source not specified\n");
+		return PTR_ERR(chip->clk);
+	}
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	chip->base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(chip->base))
+		return PTR_ERR(chip->base);
+
+	ret = clk_prepare(chip->clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to prepare clock\n");
+		return ret;
+	}
+
+	ret = pwmchip_add(&chip->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add PWM chip\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, chip);
+	return ret;
+}
+
+static int vt8500_pwm_remove(struct platform_device *pdev)
+{
+	struct vt8500_chip *chip;
+
+	chip = platform_get_drvdata(pdev);
+	if (chip == NULL)
+		return -ENODEV;
+
+	clk_unprepare(chip->clk);
+
+	return pwmchip_remove(&chip->chip);
+}
+
+static struct platform_driver vt8500_pwm_driver = {
+	.probe		= vt8500_pwm_probe,
+	.remove		= vt8500_pwm_remove,
+	.driver		= {
+		.name	= "vt8500-pwm",
+		.owner	= THIS_MODULE,
+		.of_match_table = vt8500_pwm_dt_ids,
+	},
+};
+module_platform_driver(vt8500_pwm_driver);
+
+MODULE_DESCRIPTION("VT8500 PWM Driver");
+MODULE_AUTHOR("Tony Prisk <linux@prisktech.co.nz>");
+MODULE_LICENSE("GPL v2");