Merge tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "There are two new drivers, one for the BCM2835 (Raspberry Pi) and one
  used in conjunction with the LCD controller on various Atmel SoCs.
  The Samsung PWM driver can now be built for 64-bit ARM (Exynos7).

  A couple of fixes have been applied to the FTM PWM driver and system
  sleep support was added"

* tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling
  pwm: ftm: Add Power Management support for FTM PWM
  pwm: ftm: Add regmap rbtree type cache support
  pwm: ftm: Correctly track usage count
  pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7
  pwm: add DT bindings documentation for atmel-hlcdc-pwm driver
  pwm: add support for atmel-hlcdc-pwm device
  pwm: Add BCM2835 PWM driver

5 files changed, 587 insertions, 5 deletions

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index ef2dd2e..a3ecf58 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -50,6 +50,17 @@ config PWM_ATMEL
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-atmel.
 
+config PWM_ATMEL_HLCDC_PWM
+	tristate "Atmel HLCDC PWM support"
+	depends on MFD_ATMEL_HLCDC
+	help
+	  Generic PWM framework driver for the PWM output of the HLCDC
+	  (Atmel High-end LCD Controller). This PWM output is mainly used
+	  to control the LCD backlight.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-atmel-hlcdc.
+
 config PWM_ATMEL_TCB
 	tristate "Atmel TC Block PWM support"
 	depends on ATMEL_TCLIB && OF
@@ -71,6 +82,15 @@ config PWM_BCM_KONA
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-bcm-kona.
 
+config PWM_BCM2835
+	tristate "BCM2835 PWM support"
+	depends on ARCH_BCM2835
+	help
+	  PWM framework driver for BCM2835 controller (Raspberry Pi)
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-bcm2835.
+
 config PWM_BFIN
 	tristate "Blackfin PWM support"
 	depends on BFIN_GPTIMERS
@@ -235,7 +255,7 @@ config PWM_ROCKCHIP
 
 config PWM_SAMSUNG
 	tristate "Samsung PWM support"
-	depends on PLAT_SAMSUNG
+	depends on PLAT_SAMSUNG || ARCH_EXYNOS
 	help
 	  Generic PWM framework driver for Samsung.
 
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index c458606..65259ac 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -2,8 +2,10 @@ obj-$(CONFIG_PWM)		+= core.o
 obj-$(CONFIG_PWM_SYSFS)		+= sysfs.o
 obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o
 obj-$(CONFIG_PWM_ATMEL)		+= pwm-atmel.o
+obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM)	+= pwm-atmel-hlcdc.o
 obj-$(CONFIG_PWM_ATMEL_TCB)	+= pwm-atmel-tcb.o
 obj-$(CONFIG_PWM_BCM_KONA)	+= pwm-bcm-kona.o
+obj-$(CONFIG_PWM_BCM2835)	+= pwm-bcm2835.o
 obj-$(CONFIG_PWM_BFIN)		+= pwm-bfin.o
 obj-$(CONFIG_PWM_CLPS711X)	+= pwm-clps711x.o
 obj-$(CONFIG_PWM_EP93XX)	+= pwm-ep93xx.o
diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
new file mode 100644
index 0000000..e7a785f
--- /dev/null
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2014 Free Electrons
+ * Copyright (C) 2014 Atmel
+ *
+ * Author: Boris BREZILLON <boris.brezillon@free-electrons.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/clk.h>
+#include <linux/delay.h>
+#include <linux/mfd/atmel-hlcdc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+
+#define ATMEL_HLCDC_PWMCVAL_MASK	GENMASK(15, 8)
+#define ATMEL_HLCDC_PWMCVAL(x)		(((x) << 8) & ATMEL_HLCDC_PWMCVAL_MASK)
+#define ATMEL_HLCDC_PWMPOL		BIT(4)
+#define ATMEL_HLCDC_PWMPS_MASK		GENMASK(2, 0)
+#define ATMEL_HLCDC_PWMPS_MAX		0x6
+#define ATMEL_HLCDC_PWMPS(x)		((x) & ATMEL_HLCDC_PWMPS_MASK)
+
+struct atmel_hlcdc_pwm_errata {
+	bool slow_clk_erratum;
+	bool div1_clk_erratum;
+};
+
+struct atmel_hlcdc_pwm {
+	struct pwm_chip chip;
+	struct atmel_hlcdc *hlcdc;
+	struct clk *cur_clk;
+	const struct atmel_hlcdc_pwm_errata *errata;
+};
+
+static inline struct atmel_hlcdc_pwm *to_atmel_hlcdc_pwm(struct pwm_chip *chip)
+{
+	return container_of(chip, struct atmel_hlcdc_pwm, chip);
+}
+
+static int atmel_hlcdc_pwm_config(struct pwm_chip *c,
+				  struct pwm_device *pwm,
+				  int duty_ns, int period_ns)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	struct clk *new_clk = hlcdc->slow_clk;
+	u64 pwmcval = duty_ns * 256;
+	unsigned long clk_freq;
+	u64 clk_period_ns;
+	u32 pwmcfg;
+	int pres;
+
+	if (!chip->errata || !chip->errata->slow_clk_erratum) {
+		clk_freq = clk_get_rate(new_clk);
+		clk_period_ns = (u64)NSEC_PER_SEC * 256;
+		do_div(clk_period_ns, clk_freq);
+	}
+
+	/* Errata: cannot use slow clk on some IP revisions */
+	if ((chip->errata && chip->errata->slow_clk_erratum) ||
+	    clk_period_ns > period_ns) {
+		new_clk = hlcdc->sys_clk;
+		clk_freq = clk_get_rate(new_clk);
+		clk_period_ns = (u64)NSEC_PER_SEC * 256;
+		do_div(clk_period_ns, clk_freq);
+	}
+
+	for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) {
+		/* Errata: cannot divide by 1 on some IP revisions */
+		if (!pres && chip->errata && chip->errata->div1_clk_erratum)
+			continue;
+
+		if ((clk_period_ns << pres) >= period_ns)
+			break;
+	}
+
+	if (pres > ATMEL_HLCDC_PWMPS_MAX)
+		return -EINVAL;
+
+	pwmcfg = ATMEL_HLCDC_PWMPS(pres);
+
+	if (new_clk != chip->cur_clk) {
+		u32 gencfg = 0;
+		int ret;
+
+		ret = clk_prepare_enable(new_clk);
+		if (ret)
+			return ret;
+
+		clk_disable_unprepare(chip->cur_clk);
+		chip->cur_clk = new_clk;
+
+		if (new_clk == hlcdc->sys_clk)
+			gencfg = ATMEL_HLCDC_CLKPWMSEL;
+
+		ret = regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(0),
+					 ATMEL_HLCDC_CLKPWMSEL, gencfg);
+		if (ret)
+			return ret;
+	}
+
+	do_div(pwmcval, period_ns);
+
+	/*
+	 * The PWM duty cycle is configurable from 0/256 to 255/256 of the
+	 * period cycle. Hence we can't set a duty cycle occupying the
+	 * whole period cycle if we're asked to.
+	 * Set it to 255 if pwmcval is greater than 256.
+	 */
+	if (pwmcval > 255)
+		pwmcval = 255;
+
+	pwmcfg |= ATMEL_HLCDC_PWMCVAL(pwmcval);
+
+	return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
+				  ATMEL_HLCDC_PWMCVAL_MASK |
+				  ATMEL_HLCDC_PWMPS_MASK,
+				  pwmcfg);
+}
+
+static int atmel_hlcdc_pwm_set_polarity(struct pwm_chip *c,
+					struct pwm_device *pwm,
+					enum pwm_polarity polarity)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 cfg = 0;
+
+	if (polarity == PWM_POLARITY_NORMAL)
+		cfg = ATMEL_HLCDC_PWMPOL;
+
+	return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
+				  ATMEL_HLCDC_PWMPOL, cfg);
+}
+
+static int atmel_hlcdc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 status;
+	int ret;
+
+	ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_PWM);
+	if (ret)
+		return ret;
+
+	while (true) {
+		ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
+		if (ret)
+			return ret;
+
+		if ((status & ATMEL_HLCDC_PWM) != 0)
+			break;
+
+		usleep_range(1, 10);
+	}
+
+	return 0;
+}
+
+static void atmel_hlcdc_pwm_disable(struct pwm_chip *c,
+				    struct pwm_device *pwm)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 status;
+	int ret;
+
+	ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_PWM);
+	if (ret)
+		return;
+
+	while (true) {
+		ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
+		if (ret)
+			return;
+
+		if ((status & ATMEL_HLCDC_PWM) == 0)
+			break;
+
+		usleep_range(1, 10);
+	}
+}
+
+static const struct pwm_ops atmel_hlcdc_pwm_ops = {
+	.config = atmel_hlcdc_pwm_config,
+	.set_polarity = atmel_hlcdc_pwm_set_polarity,
+	.enable = atmel_hlcdc_pwm_enable,
+	.disable = atmel_hlcdc_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_at91sam9x5_errata = {
+	.slow_clk_erratum = true,
+};
+
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_sama5d3_errata = {
+	.div1_clk_erratum = true,
+};
+
+static const struct of_device_id atmel_hlcdc_dt_ids[] = {
+	{
+		.compatible = "atmel,at91sam9x5-hlcdc",
+		.data = &atmel_hlcdc_pwm_at91sam9x5_errata,
+	},
+	{
+		.compatible = "atmel,sama5d3-hlcdc",
+		.data = &atmel_hlcdc_pwm_sama5d3_errata,
+	},
+	{ /* sentinel */ },
+};
+
+static int atmel_hlcdc_pwm_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	struct atmel_hlcdc_pwm *chip;
+	struct atmel_hlcdc *hlcdc;
+	int ret;
+
+	hlcdc = dev_get_drvdata(dev->parent);
+
+	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(hlcdc->periph_clk);
+	if (ret)
+		return ret;
+
+	match = of_match_node(atmel_hlcdc_dt_ids, dev->parent->of_node);
+	if (match)
+		chip->errata = match->data;
+
+	chip->hlcdc = hlcdc;
+	chip->chip.ops = &atmel_hlcdc_pwm_ops;
+	chip->chip.dev = dev;
+	chip->chip.base = -1;
+	chip->chip.npwm = 1;
+	chip->chip.of_xlate = of_pwm_xlate_with_flags;
+	chip->chip.of_pwm_n_cells = 3;
+	chip->chip.can_sleep = 1;
+
+	ret = pwmchip_add(&chip->chip);
+	if (ret) {
+		clk_disable_unprepare(hlcdc->periph_clk);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, chip);
+
+	return 0;
+}
+
+static int atmel_hlcdc_pwm_remove(struct platform_device *pdev)
+{
+	struct atmel_hlcdc_pwm *chip = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = pwmchip_remove(&chip->chip);
+	if (ret)
+		return ret;
+
+	clk_disable_unprepare(chip->hlcdc->periph_clk);
+
+	return 0;
+}
+
+static const struct of_device_id atmel_hlcdc_pwm_dt_ids[] = {
+	{ .compatible = "atmel,hlcdc-pwm" },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver atmel_hlcdc_pwm_driver = {
+	.driver = {
+		.name = "atmel-hlcdc-pwm",
+		.of_match_table = atmel_hlcdc_pwm_dt_ids,
+	},
+	.probe = atmel_hlcdc_pwm_probe,
+	.remove = atmel_hlcdc_pwm_remove,
+};
+module_platform_driver(atmel_hlcdc_pwm_driver);
+
+MODULE_ALIAS("platform:atmel-hlcdc-pwm");
+MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
+MODULE_DESCRIPTION("Atmel HLCDC PWM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c
new file mode 100644
index 0000000..b4c7f95
--- /dev/null
+++ b/drivers/pwm/pwm-bcm2835.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright 2014 Bart Tanghe <bart.tanghe@thomasmore.be>
+ *
+ * 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/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+#define PWM_CONTROL		0x000
+#define PWM_CONTROL_SHIFT(x)	((x) * 8)
+#define PWM_CONTROL_MASK	0xff
+#define PWM_MODE		0x80		/* set timer in PWM mode */
+#define PWM_ENABLE		(1 << 0)
+#define PWM_POLARITY		(1 << 4)
+
+#define PERIOD(x)		(((x) * 0x10) + 0x10)
+#define DUTY(x)			(((x) * 0x10) + 0x14)
+
+#define MIN_PERIOD		108		/* 9.2 MHz max. PWM clock */
+
+struct bcm2835_pwm {
+	struct pwm_chip chip;
+	struct device *dev;
+	unsigned long scaler;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+static inline struct bcm2835_pwm *to_bcm2835_pwm(struct pwm_chip *chip)
+{
+	return container_of(chip, struct bcm2835_pwm, chip);
+}
+
+static int bcm2835_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+	u32 value;
+
+	value = readl(pc->base + PWM_CONTROL);
+	value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm));
+	value |= (PWM_MODE << PWM_CONTROL_SHIFT(pwm->hwpwm));
+	writel(value, pc->base + PWM_CONTROL);
+
+	return 0;
+}
+
+static void bcm2835_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+	u32 value;
+
+	value = readl(pc->base + PWM_CONTROL);
+	value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm));
+	writel(value, pc->base + PWM_CONTROL);
+}
+
+static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+
+	if (period_ns <= MIN_PERIOD) {
+		dev_err(pc->dev, "period %d not supported, minimum %d\n",
+			period_ns, MIN_PERIOD);
+		return -EINVAL;
+	}
+
+	writel(duty_ns / pc->scaler, pc->base + DUTY(pwm->hwpwm));
+	writel(period_ns / pc->scaler, pc->base + PERIOD(pwm->hwpwm));
+
+	return 0;
+}
+
+static int bcm2835_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+	u32 value;
+
+	value = readl(pc->base + PWM_CONTROL);
+	value |= PWM_ENABLE << PWM_CONTROL_SHIFT(pwm->hwpwm);
+	writel(value, pc->base + PWM_CONTROL);
+
+	return 0;
+}
+
+static void bcm2835_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+	u32 value;
+
+	value = readl(pc->base + PWM_CONTROL);
+	value &= ~(PWM_ENABLE << PWM_CONTROL_SHIFT(pwm->hwpwm));
+	writel(value, pc->base + PWM_CONTROL);
+}
+
+static int bcm2835_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
+				enum pwm_polarity polarity)
+{
+	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+	u32 value;
+
+	value = readl(pc->base + PWM_CONTROL);
+
+	if (polarity == PWM_POLARITY_NORMAL)
+		value &= ~(PWM_POLARITY << PWM_CONTROL_SHIFT(pwm->hwpwm));
+	else
+		value |= PWM_POLARITY << PWM_CONTROL_SHIFT(pwm->hwpwm);
+
+	writel(value, pc->base + PWM_CONTROL);
+
+	return 0;
+}
+
+static const struct pwm_ops bcm2835_pwm_ops = {
+	.request = bcm2835_pwm_request,
+	.free = bcm2835_pwm_free,
+	.config = bcm2835_pwm_config,
+	.enable = bcm2835_pwm_enable,
+	.disable = bcm2835_pwm_disable,
+	.set_polarity = bcm2835_set_polarity,
+	.owner = THIS_MODULE,
+};
+
+static int bcm2835_pwm_probe(struct platform_device *pdev)
+{
+	struct bcm2835_pwm *pc;
+	struct resource *res;
+	int ret;
+
+	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
+	if (!pc)
+		return -ENOMEM;
+
+	pc->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pc->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(pc->base))
+		return PTR_ERR(pc->base);
+
+	pc->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(pc->clk)) {
+		dev_err(&pdev->dev, "clock not found: %ld\n", PTR_ERR(pc->clk));
+		return PTR_ERR(pc->clk);
+	}
+
+	ret = clk_prepare_enable(pc->clk);
+	if (ret)
+		return ret;
+
+	pc->scaler = NSEC_PER_SEC / clk_get_rate(pc->clk);
+
+	pc->chip.dev = &pdev->dev;
+	pc->chip.ops = &bcm2835_pwm_ops;
+	pc->chip.npwm = 2;
+
+	platform_set_drvdata(pdev, pc);
+
+	ret = pwmchip_add(&pc->chip);
+	if (ret < 0)
+		goto add_fail;
+
+	return 0;
+
+add_fail:
+	clk_disable_unprepare(pc->clk);
+	return ret;
+}
+
+static int bcm2835_pwm_remove(struct platform_device *pdev)
+{
+	struct bcm2835_pwm *pc = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(pc->clk);
+
+	return pwmchip_remove(&pc->chip);
+}
+
+static const struct of_device_id bcm2835_pwm_of_match[] = {
+	{ .compatible = "brcm,bcm2835-pwm", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, bcm2835_pwm_of_match);
+
+static struct platform_driver bcm2835_pwm_driver = {
+	.driver = {
+		.name = "bcm2835-pwm",
+		.of_match_table = bcm2835_pwm_of_match,
+	},
+	.probe = bcm2835_pwm_probe,
+	.remove = bcm2835_pwm_remove,
+};
+module_platform_driver(bcm2835_pwm_driver);
+
+MODULE_AUTHOR("Bart Tanghe <bart.tanghe@thomasmore.be");
+MODULE_DESCRIPTION("Broadcom BCM2835 PWM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 0f2cc7e..f9dfc8b 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -17,6 +17,7 @@
 #include <linux/mutex.h>
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
 #include <linux/pwm.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
@@ -299,7 +300,7 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
 {
 	int ret;
 
-	if (fpc->use_count != 0)
+	if (fpc->use_count++ != 0)
 		return 0;
 
 	/* select counter clock source */
@@ -316,8 +317,6 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
 		return ret;
 	}
 
-	fpc->use_count++;
-
 	return 0;
 }
 
@@ -399,12 +398,23 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
 	return 0;
 }
 
+static bool fsl_pwm_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case FTM_CNT:
+		return true;
+	}
+	return false;
+}
+
 static const struct regmap_config fsl_pwm_regmap_config = {
 	.reg_bits = 32,
 	.reg_stride = 4,
 	.val_bits = 32,
 
 	.max_register = FTM_PWMLOAD,
+	.volatile_reg = fsl_pwm_volatile_reg,
+	.cache_type = REGCACHE_RBTREE,
 };
 
 static int fsl_pwm_probe(struct platform_device *pdev)
@@ -427,7 +437,7 @@ static int fsl_pwm_probe(struct platform_device *pdev)
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
-	fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
+	fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "ftm_sys", base,
 						&fsl_pwm_regmap_config);
 	if (IS_ERR(fpc->regmap)) {
 		dev_err(&pdev->dev, "regmap init failed\n");
@@ -478,6 +488,51 @@ static int fsl_pwm_remove(struct platform_device *pdev)
 	return pwmchip_remove(&fpc->chip);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int fsl_pwm_suspend(struct device *dev)
+{
+	struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
+	u32 val;
+
+	regcache_cache_only(fpc->regmap, true);
+	regcache_mark_dirty(fpc->regmap);
+
+	/* read from cache */
+	regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+	if ((val & 0xFF) != 0xFF) {
+		clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
+		clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
+		clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
+	}
+
+	return 0;
+}
+
+static int fsl_pwm_resume(struct device *dev)
+{
+	struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
+	u32 val;
+
+	/* read from cache */
+	regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+	if ((val & 0xFF) != 0xFF) {
+		clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
+		clk_prepare_enable(fpc->clk[fpc->cnt_select]);
+		clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
+	}
+
+	/* restore all registers from cache */
+	regcache_cache_only(fpc->regmap, false);
+	regcache_sync(fpc->regmap);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops fsl_pwm_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(fsl_pwm_suspend, fsl_pwm_resume)
+};
+
 static const struct of_device_id fsl_pwm_dt_ids[] = {
 	{ .compatible = "fsl,vf610-ftm-pwm", },
 	{ /* sentinel */ }
@@ -488,6 +543,7 @@ static struct platform_driver fsl_pwm_driver = {
 	.driver = {
 		.name = "fsl-ftm-pwm",
 		.of_match_table = fsl_pwm_dt_ids,
+		.pm = &fsl_pwm_pm_ops,
 	},
 	.probe = fsl_pwm_probe,
 	.remove = fsl_pwm_remove,