Merge tag 'pwm/for-4.14-rc1' of...

Merge tag 'pwm/for-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "The changes for this release include a new driver for the PWM
  controller found on SoCs of the ZTX ZX family. Support for an old
  SH-Mobile SoC has been dropped and the Rockchip and MediaTek drivers
  gain support for more generations.

  Other than that there are a bunch of coding style fixes, minor bug
  fixes and cleanup as well as documentation patches"

* tag 'pwm/for-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (32 commits)
  pwm: pwm-samsung: fix suspend/resume support
  pwm: samsung: Remove redundant checks from pwm_samsung_config()
  pwm: mediatek: Disable clock on PWM configuration failure
  dt-bindings: pwm: Add MT2712/MT7622 information
  pwm: mediatek: Fix clock control issue
  pwm: mediatek: Fix PWM source clock selection
  pwm: mediatek: Fix Kconfig description
  pwm: tegra: Explicitly request exclusive reset control
  pwm: hibvt: Explicitly request exclusive reset control
  pwm: tiehrpwm: Set driver data before runtime PM enable
  pwm: tiehrpwm: Miscellaneous coding style fixups
  pwm: tiecap: Set driver data before runtime PM enable
  pwm: tiecap: Miscellaneous coding style fixups
  dt-bindings: pwm: tiecap: Add TI 66AK2G SoC specific compatible
  pwm: tiehrpwm: fix clock imbalance in probe error path
  pwm: tiehrpwm: Fix runtime PM imbalance at unbind
  pwm: Kconfig: Enable pwm-tiecap to be built for Keystone
  pwm: Add ZTE ZX PWM device driver
  dt-bindings: pwm: Add bindings doc for ZTE ZX PWM controller
  pwm: bcm2835: Support for polarity setting via DT
  ...

Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt

@@ -6,7 +6,7 @@ Required properties:
 - clocks: This clock defines the base clock frequency of the PWM hardware
   system, the period and the duty_cycle of the PWM signal is a multiple of
   the base period.
-- #pwm-cells: Should be 2. See pwm.txt in this directory for a description of
+- #pwm-cells: Should be 3. See pwm.txt in this directory for a description of
   the cells format.
 
 Examples:
@@ -15,7 +15,7 @@ pwm@2020c000 {
 	compatible = "brcm,bcm2835-pwm";
 	reg = <0x2020c000 0x28>;
 	clocks = <&clk_pwm>;
-	#pwm-cells = <2>;
+	#pwm-cells = <3>;
 };
 
 clocks {

Documentation/devicetree/bindings/pwm/pwm-mediatek.txt

@@ -2,6 +2,8 @@ MediaTek PWM controller
 
 Required properties:
  - compatible: should be "mediatek,<name>-pwm":
+   - "mediatek,mt2712-pwm": found on mt2712 SoC.
+   - "mediatek,mt7622-pwm": found on mt7622 SoC.
    - "mediatek,mt7623-pwm": found on mt7623 SoC.
  - reg: physical base address and length of the controller's registers.
  - #pwm-cells: must be 2. See pwm.txt in this directory for a description of
@@ -10,7 +12,9 @@ Required properties:
  - clock-names: must contain the following:
    - "top": the top clock generator
    - "main": clock used by the PWM core
-   - "pwm1-5": the five per PWM clocks
+   - "pwm1-8": the eight per PWM clocks for mt2712
+   - "pwm1-6": the six per PWM clocks for mt7622
+   - "pwm1-5": the five per PWM clocks for mt7623
  - pinctrl-names: Must contain a "default" entry.
  - pinctrl-0: One property must exist for each entry in pinctrl-names.
    See pinctrl/pinctrl-bindings.txt for details of the property values.

Documentation/devicetree/bindings/pwm/pwm-rockchip.txt

@@ -3,10 +3,17 @@ Rockchip PWM controller
 Required properties:
  - compatible: should be "rockchip,<name>-pwm"
    "rockchip,rk2928-pwm": found on RK29XX,RK3066 and RK3188 SoCs
-   "rockchip,rk3288-pwm": found on RK3288 SoC
+   "rockchip,rk3288-pwm": found on RK3288 SOC
+   "rockchip,rv1108-pwm", "rockchip,rk3288-pwm": found on RV1108 SoC
    "rockchip,vop-pwm": found integrated in VOP on RK3288 SoC
  - reg: physical base address and length of the controller's registers
- - clocks: phandle and clock specifier of the PWM reference clock
+ - clocks: See ../clock/clock-bindings.txt
+   - For older hardware (rk2928, rk3066, rk3188, rk3228, rk3288, rk3399):
+     - There is one clock that's used both to derive the functional clock
+       for the device and as the bus clock.
+   - For newer hardware (rk3328 and future socs): specified by name
+     - "pwm": This is used to derive the functional clock.
+     - "pclk": This is the APB bus clock.
  - #pwm-cells: must be 2 (rk2928) or 3 (rk3288). See pwm.txt in this directory
    for a description of the cell format.
 

Documentation/devicetree/bindings/pwm/pwm-tiecap.txt

@@ -6,6 +6,7 @@ Required properties:
   for am4372 - compatible = "ti,am4372-ecap", "ti,am3352-ecap", "ti,am33xx-ecap";
   for da850  - compatible = "ti,da850-ecap", "ti,am3352-ecap", "ti,am33xx-ecap";
   for dra746 - compatible = "ti,dra746-ecap", "ti,am3352-ecap";
+  for 66ak2g - compatible = "ti,k2g-ecap", "ti,am3352-ecap";
 - #pwm-cells: should be 3. See pwm.txt in this directory for a description of
   the cells format. The PWM channel index ranges from 0 to 4. The only third
   cell flag supported by this binding is PWM_POLARITY_INVERTED.

Documentation/devicetree/bindings/pwm/pwm-zx.txt

+ZTE ZX PWM controller
+
+Required properties:
+ - compatible: Should be "zte,zx296718-pwm".
+ - reg: Physical base address and length of the controller's registers.
+ - clocks : The phandle and specifier referencing the controller's clocks.
+ - clock-names: "pclk" for PCLK, "wclk" for WCLK to the PWM controller.  The
+   PCLK is for register access, while WCLK is the reference clock for
+   calculating period and duty cycles.
+ - #pwm-cells: Should be 3. See pwm.txt in this directory for a description of
+   the cells format.
+
+Example:
+
+	pwm: pwm@1439000 {
+		compatible = "zte,zx296718-pwm";
+		reg = <0x1439000 0x1000>;
+		clocks = <&lsp1crm LSP1_PWM_PCLK>,
+			 <&lsp1crm LSP1_PWM_WCLK>;
+		clock-names = "pclk", "wclk";
+		#pwm-cells = <3>;
+	};

Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt

@@ -6,7 +6,6 @@ Required Properties:
     - "renesas,tpu-r8a73a4": for R8A77A4 (R-Mobile APE6) compatible PWM controller.
     - "renesas,tpu-r8a7740": for R8A7740 (R-Mobile A1) compatible PWM controller.
     - "renesas,tpu-r8a7790": for R8A7790 (R-Car H2) compatible PWM controller.
-    - "renesas,tpu-sh7372": for SH7372 (SH-Mobile AP4) compatible PWM controller.
     - "renesas,tpu": for generic R-Car TPU PWM controller.
 
   - reg: Base address and length of each memory resource used by the PWM

drivers/pwm/Kconfig

@@ -300,7 +300,7 @@ config PWM_MEDIATEK
 	  Generic PWM framework driver for Mediatek ARM SoC.
 
 	  To compile this driver as a module, choose M here: the module
-	  will be called pwm-mxs.
+	  will be called pwm-mediatek.
 
 config PWM_MXS
 	tristate "Freescale MXS PWM support"
@@ -456,7 +456,7 @@ config PWM_TEGRA
 
 config  PWM_TIECAP
 	tristate "ECAP PWM support"
-	depends on ARCH_OMAP2PLUS || ARCH_DAVINCI_DA8XX
+	depends on ARCH_OMAP2PLUS || ARCH_DAVINCI_DA8XX || ARCH_KEYSTONE
 	help
 	  PWM driver support for the ECAP APWM controller found on AM33XX
 	  TI SOC
@@ -510,4 +510,13 @@ config PWM_VT8500
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-vt8500.
 
+config PWM_ZX
+	tristate "ZTE ZX PWM support"
+	depends on ARCH_ZX
+	help
+	  Generic PWM framework driver for ZTE ZX family SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-zx.
+
 endif

drivers/pwm/Makefile

@@ -50,3 +50,4 @@ 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
+obj-$(CONFIG_PWM_ZX)		+= pwm-zx.o

drivers/pwm/pwm-bcm2835.c

@@ -167,6 +167,8 @@ static int bcm2835_pwm_probe(struct platform_device *pdev)
 	pc->chip.dev = &pdev->dev;
 	pc->chip.ops = &bcm2835_pwm_ops;
 	pc->chip.npwm = 2;
+	pc->chip.of_xlate = of_pwm_xlate_with_flags;
+	pc->chip.of_pwm_n_cells = 3;
 
 	platform_set_drvdata(pdev, pc);
 

drivers/pwm/pwm-hibvt.c

@@ -208,7 +208,7 @@ static int hibvt_pwm_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
-	pwm_chip->rstc = devm_reset_control_get(&pdev->dev, NULL);
+	pwm_chip->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
 	if (IS_ERR(pwm_chip->rstc)) {
 		clk_disable_unprepare(pwm_chip->clk);
 		return PTR_ERR(pwm_chip->rstc);

drivers/pwm/pwm-mediatek.c

@@ -2,6 +2,7 @@
  * Mediatek Pulse Width Modulator driver
  *
  * Copyright (C) 2015 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2017 Zhi Mao <zhi.mao@mediatek.com>
  *
  * This file is licensed under the terms of the GNU General Public
  * License version 2. This program is licensed "as is" without any
@@ -29,6 +30,8 @@
 #define PWMDWIDTH		0x2c
 #define PWMTHRES		0x30
 
+#define PWM_CLK_DIV_MAX		7
+
 enum {
 	MTK_CLK_MAIN = 0,
 	MTK_CLK_TOP,
@@ -61,6 +64,42 @@ static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct pwm_chip *chip)
 	return container_of(chip, struct mtk_pwm_chip, chip);
 }
 
+static int mtk_pwm_clk_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
+	int ret;
+
+	ret = clk_prepare_enable(pc->clks[MTK_CLK_TOP]);
+	if (ret < 0)
+		return ret;
+
+	ret = clk_prepare_enable(pc->clks[MTK_CLK_MAIN]);
+	if (ret < 0)
+		goto disable_clk_top;
+
+	ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+	if (ret < 0)
+		goto disable_clk_main;
+
+	return 0;
+
+disable_clk_main:
+	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
+disable_clk_top:
+	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
+
+	return ret;
+}
+
+static void mtk_pwm_clk_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
+
+	clk_disable_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
+	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
+}
+
 static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
 				unsigned int offset)
 {
@@ -80,6 +119,11 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
 	struct clk *clk = pc->clks[MTK_CLK_PWM1 + pwm->hwpwm];
 	u32 resolution, clkdiv = 0;
+	int ret;
+
+	ret = mtk_pwm_clk_enable(chip, pwm);
+	if (ret < 0)
+		return ret;
 
 	resolution = NSEC_PER_SEC / clk_get_rate(clk);
 
@@ -88,13 +132,18 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		clkdiv++;
 	}
 
-	if (clkdiv > 7)
+	if (clkdiv > PWM_CLK_DIV_MAX) {
+		mtk_pwm_clk_disable(chip, pwm);
+		dev_err(chip->dev, "period %d not supported\n", period_ns);
 		return -EINVAL;
+	}
 
-	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | BIT(3) | clkdiv);
+	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv);
 	mtk_pwm_writel(pc, pwm->hwpwm, PWMDWIDTH, period_ns / resolution);
 	mtk_pwm_writel(pc, pwm->hwpwm, PWMTHRES, duty_ns / resolution);
 
+	mtk_pwm_clk_disable(chip, pwm);
+
 	return 0;
 }
 
@@ -104,7 +153,7 @@ static int mtk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	u32 value;
 	int ret;
 
-	ret = clk_prepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+	ret = mtk_pwm_clk_enable(chip, pwm);
 	if (ret < 0)
 		return ret;
 
@@ -124,7 +173,7 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	value &= ~BIT(pwm->hwpwm);
 	writel(value, pc->regs);
 
-	clk_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+	mtk_pwm_clk_disable(chip, pwm);
 }
 
 static const struct pwm_ops mtk_pwm_ops = {
@@ -156,14 +205,6 @@ static int mtk_pwm_probe(struct platform_device *pdev)
 			return PTR_ERR(pc->clks[i]);
 	}
 
-	ret = clk_prepare(pc->clks[MTK_CLK_TOP]);
-	if (ret < 0)
-		return ret;
-
-	ret = clk_prepare(pc->clks[MTK_CLK_MAIN]);
-	if (ret < 0)
-		goto disable_clk_top;
-
 	platform_set_drvdata(pdev, pc);
 
 	pc->chip.dev = &pdev->dev;
@@ -174,26 +215,15 @@ static int mtk_pwm_probe(struct platform_device *pdev)
 	ret = pwmchip_add(&pc->chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
-		goto disable_clk_main;
+		return ret;
 	}
 
 	return 0;
-
-disable_clk_main:
-	clk_unprepare(pc->clks[MTK_CLK_MAIN]);
-disable_clk_top:
-	clk_unprepare(pc->clks[MTK_CLK_TOP]);
-
-	return ret;
 }
 
 static int mtk_pwm_remove(struct platform_device *pdev)
 {
 	struct mtk_pwm_chip *pc = platform_get_drvdata(pdev);
-	unsigned int i;
-
-	for (i = 0; i < pc->chip.npwm; i++)
-		pwm_disable(&pc->chip.pwms[i]);
 
 	return pwmchip_remove(&pc->chip);
 }

drivers/pwm/pwm-meson.c

@@ -441,7 +441,7 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
 	for (i = 0; i < meson->chip.npwm; i++) {
 		struct meson_pwm_channel *channel = &channels[i];
 
-		snprintf(name, sizeof(name), "%s#mux%u", np->full_name, i);
+		snprintf(name, sizeof(name), "%pOF#mux%u", np, i);
 
 		init.name = name;
 		init.ops = &clk_mux_ops;

drivers/pwm/pwm-pca9685.c

@@ -241,11 +241,11 @@ static inline int pca9685_pwm_gpio_probe(struct pca9685 *pca)
 }
 #endif
 
-static void pca9685_set_sleep_mode(struct pca9685 *pca, int sleep)
+static void pca9685_set_sleep_mode(struct pca9685 *pca, bool enable)
 {
 	regmap_update_bits(pca->regmap, PCA9685_MODE1,
-			   MODE1_SLEEP, sleep ? MODE1_SLEEP : 0);
-	if (!sleep) {
+			   MODE1_SLEEP, enable ? MODE1_SLEEP : 0);
+	if (!enable) {
 		/* Wait 500us for the oscillator to be back up */
 		udelay(500);
 	}
@@ -272,13 +272,13 @@ static int pca9685_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 			 * state is guaranteed active here.
 			 */
 			/* Put chip into sleep mode */
-			pca9685_set_sleep_mode(pca, 1);
+			pca9685_set_sleep_mode(pca, true);
 
 			/* Change the chip-wide output frequency */
 			regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);
 
 			/* Wake the chip up */
-			pca9685_set_sleep_mode(pca, 0);
+			pca9685_set_sleep_mode(pca, false);
 
 			pca->period_ns = period_ns;
 		} else {
@@ -534,7 +534,7 @@ static int pca9685_pwm_runtime_suspend(struct device *dev)
 	struct i2c_client *client = to_i2c_client(dev);
 	struct pca9685 *pca = i2c_get_clientdata(client);
 
-	pca9685_set_sleep_mode(pca, 1);
+	pca9685_set_sleep_mode(pca, true);
 	return 0;
 }
 
@@ -543,7 +543,7 @@ static int pca9685_pwm_runtime_resume(struct device *dev)
 	struct i2c_client *client = to_i2c_client(dev);
 	struct pca9685 *pca = i2c_get_clientdata(client);
 
-	pca9685_set_sleep_mode(pca, 0);
+	pca9685_set_sleep_mode(pca, false);
 	return 0;
 }
 #endif

drivers/pwm/pwm-renesas-tpu.c

@@ -455,7 +455,6 @@ static const struct of_device_id tpu_of_table[] = {
 	{ .compatible = "renesas,tpu-r8a73a4", },
 	{ .compatible = "renesas,tpu-r8a7740", },
 	{ .compatible = "renesas,tpu-r8a7790", },
-	{ .compatible = "renesas,tpu-sh7372", },
 	{ .compatible = "renesas,tpu", },
 	{ },
 };

drivers/pwm/pwm-rockchip.c

@@ -27,12 +27,15 @@
 #define PWM_DUTY_NEGATIVE	(0 << 3)
 #define PWM_INACTIVE_NEGATIVE	(0 << 4)
 #define PWM_INACTIVE_POSITIVE	(1 << 4)
+#define PWM_POLARITY_MASK	(PWM_DUTY_POSITIVE | PWM_INACTIVE_POSITIVE)
 #define PWM_OUTPUT_LEFT		(0 << 5)
+#define PWM_LOCK_EN		(1 << 6)
 #define PWM_LP_DISABLE		(0 << 8)
 
 struct rockchip_pwm_chip {
 	struct pwm_chip chip;
 	struct clk *clk;
+	struct clk *pclk;
 	const struct rockchip_pwm_data *data;
 	void __iomem *base;
 };
@@ -48,13 +51,8 @@ struct rockchip_pwm_data {
 	struct rockchip_pwm_regs regs;
 	unsigned int prescaler;
 	bool supports_polarity;
-	const struct pwm_ops *ops;
-
-	void (*set_enable)(struct pwm_chip *chip,
-			   struct pwm_device *pwm, bool enable,
-			   enum pwm_polarity polarity);
-	void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm,
-			  struct pwm_state *state);
+	bool supports_lock;
+	u32 enable_conf;
 };
 
 static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
@@ -62,90 +60,18 @@ static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
 	return container_of(c, struct rockchip_pwm_chip, chip);
 }
 
-static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip,
-				       struct pwm_device *pwm, bool enable,
-				       enum pwm_polarity polarity)
-{
-	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
-	u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
-	u32 val;
-
-	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
-
-	if (enable)
-		val |= enable_conf;
-	else
-		val &= ~enable_conf;
-
-	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
-}
-
-static void rockchip_pwm_get_state_v1(struct pwm_chip *chip,
-				      struct pwm_device *pwm,
-				      struct pwm_state *state)
-{
-	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
-	u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
-	u32 val;
-
-	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
-	if ((val & enable_conf) == enable_conf)
-		state->enabled = true;
-}
-
-static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip,
-				       struct pwm_device *pwm, bool enable,
-				       enum pwm_polarity polarity)
-{
-	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
-	u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
-			  PWM_CONTINUOUS;
-	u32 val;
-
-	if (polarity == PWM_POLARITY_INVERSED)
-		enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
-	else
-		enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
-
-	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
-
-	if (enable)
-		val |= enable_conf;
-	else
-		val &= ~enable_conf;
-
-	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
-}
-
-static void rockchip_pwm_get_state_v2(struct pwm_chip *chip,
-				      struct pwm_device *pwm,
-				      struct pwm_state *state)
-{
-	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
-	u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
-			  PWM_CONTINUOUS;
-	u32 val;
-
-	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
-	if ((val & enable_conf) != enable_conf)
-		return;
-
-	state->enabled = true;
-
-	if (!(val & PWM_DUTY_POSITIVE))
-		state->polarity = PWM_POLARITY_INVERSED;
-}
-
 static void rockchip_pwm_get_state(struct pwm_chip *chip,
 				   struct pwm_device *pwm,
 				   struct pwm_state *state)
 {
 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+	u32 enable_conf = pc->data->enable_conf;
 	unsigned long clk_rate;
 	u64 tmp;
+	u32 val;
 	int ret;
 
-	ret = clk_enable(pc->clk);
+	ret = clk_enable(pc->pclk);
 	if (ret)
 		return;
 
@@ -157,19 +83,31 @@ static void rockchip_pwm_get_state(struct pwm_chip *chip,
 
 	tmp = readl_relaxed(pc->base + pc->data->regs.duty);
 	tmp *= pc->data->prescaler * NSEC_PER_SEC;
-	state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+	state->duty_cycle =  DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+
+	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+	if (pc->data->supports_polarity)
+		state->enabled = ((val & enable_conf) != enable_conf) ?
+				 false : true;
+	else
+		state->enabled = ((val & enable_conf) == enable_conf) ?
+				 true : false;
 
-	pc->data->get_state(chip, pwm, state);
+	if (pc->data->supports_polarity) {
+		if (!(val & PWM_DUTY_POSITIVE))
+			state->polarity = PWM_POLARITY_INVERSED;
+	}
 
-	clk_disable(pc->clk);
+	clk_disable(pc->pclk);
 }
 
-static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
-			       int duty_ns, int period_ns)
+static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			       struct pwm_state *state)
 {
 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
 	unsigned long period, duty;
 	u64 clk_rate, div;
+	u32 ctrl;
 
 	clk_rate = clk_get_rate(pc->clk);
 
@@ -178,26 +116,53 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * bits, every possible input period can be obtained using the
 	 * default prescaler value for all practical clock rate values.
 	 */
-	div = clk_rate * period_ns;
+	div = clk_rate * state->period;
 	period = DIV_ROUND_CLOSEST_ULL(div,
 				       pc->data->prescaler * NSEC_PER_SEC);
 
-	div = clk_rate * duty_ns;
+	div = clk_rate * state->duty_cycle;
 	duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
 
+	/*
+	 * Lock the period and duty of previous configuration, then
+	 * change the duty and period, that would not be effective.
+	 */
+	ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
+	if (pc->data->supports_lock) {
+		ctrl |= PWM_LOCK_EN;
+		writel_relaxed(ctrl, pc->base + pc->data->regs.ctrl);
+	}
+
 	writel(period, pc->base + pc->data->regs.period);
 	writel(duty, pc->base + pc->data->regs.duty);
 
-	return 0;
+	if (pc->data->supports_polarity) {
+		ctrl &= ~PWM_POLARITY_MASK;
+		if (state->polarity == PWM_POLARITY_INVERSED)
+			ctrl |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
+		else
+			ctrl |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
+	}
+
+	/*
+	 * Unlock and set polarity at the same time,
+	 * the configuration of duty, period and polarity
+	 * would be effective together at next period.
+	 */
+	if (pc->data->supports_lock)
+		ctrl &= ~PWM_LOCK_EN;
+
+	writel(ctrl, pc->base + pc->data->regs.ctrl);
 }
 
 static int rockchip_pwm_enable(struct pwm_chip *chip,
-			 struct pwm_device *pwm,
-			 bool enable,
-			 enum pwm_polarity polarity)
+			       struct pwm_device *pwm,
+			       bool enable)
 {
 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+	u32 enable_conf = pc->data->enable_conf;
 	int ret;
+	u32 val;
 
 	if (enable) {
 		ret = clk_enable(pc->clk);
@@ -205,7 +170,14 @@ static int rockchip_pwm_enable(struct pwm_chip *chip,
 			return ret;
 	}
 
-	pc->data->set_enable(chip, pwm, enable, polarity);
+	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+
+	if (enable)
+		val |= enable_conf;
+	else
+		val &= ~enable_conf;
+
+	writel_relaxed(val, pc->base + pc->data->regs.ctrl);
 
 	if (!enable)
 		clk_disable(pc->clk);
@@ -219,33 +191,26 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
 	struct pwm_state curstate;
 	bool enabled;
-	int ret;
+	int ret = 0;
 
-	pwm_get_state(pwm, &curstate);
-	enabled = curstate.enabled;
-
-	ret = clk_enable(pc->clk);
+	ret = clk_enable(pc->pclk);
 	if (ret)
 		return ret;
 
-	if (state->polarity != curstate.polarity && enabled) {
-		ret = rockchip_pwm_enable(chip, pwm, false, state->polarity);
+	pwm_get_state(pwm, &curstate);
+	enabled = curstate.enabled;
+
+	if (state->polarity != curstate.polarity && enabled &&
+	    !pc->data->supports_lock) {
+		ret = rockchip_pwm_enable(chip, pwm, false);
 		if (ret)
 			goto out;
 		enabled = false;
 	}
 
-	ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period);
-	if (ret) {
-		if (enabled != curstate.enabled)
-			rockchip_pwm_enable(chip, pwm, !enabled,
-				      state->polarity);
-		goto out;
-	}
-
+	rockchip_pwm_config(chip, pwm, state);
 	if (state->enabled != enabled) {
-		ret = rockchip_pwm_enable(chip, pwm, state->enabled,
-				    state->polarity);
+		ret = rockchip_pwm_enable(chip, pwm, state->enabled);
 		if (ret)
 			goto out;
 	}
@@ -257,18 +222,12 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	rockchip_pwm_get_state(chip, pwm, state);
 
 out:
-	clk_disable(pc->clk);
+	clk_disable(pc->pclk);
 
 	return ret;
 }
 
-static const struct pwm_ops rockchip_pwm_ops_v1 = {
-	.get_state = rockchip_pwm_get_state,
-	.apply = rockchip_pwm_apply,
-	.owner = THIS_MODULE,
-};
-
-static const struct pwm_ops rockchip_pwm_ops_v2 = {
+static const struct pwm_ops rockchip_pwm_ops = {
 	.get_state = rockchip_pwm_get_state,
 	.apply = rockchip_pwm_apply,
 	.owner = THIS_MODULE,
@@ -282,9 +241,9 @@ static const struct rockchip_pwm_data pwm_data_v1 = {
 		.ctrl = 0x0c,
 	},
 	.prescaler = 2,
-	.ops = &rockchip_pwm_ops_v1,
-	.set_enable = rockchip_pwm_set_enable_v1,
-	.get_state = rockchip_pwm_get_state_v1,
+	.supports_polarity = false,
+	.supports_lock = false,
+	.enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN,
 };
 
 static const struct rockchip_pwm_data pwm_data_v2 = {
@@ -296,9 +255,9 @@ static const struct rockchip_pwm_data pwm_data_v2 = {
 	},
 	.prescaler = 1,
 	.supports_polarity = true,
-	.ops = &rockchip_pwm_ops_v2,
-	.set_enable = rockchip_pwm_set_enable_v2,
-	.get_state = rockchip_pwm_get_state_v2,
+	.supports_lock = false,
+	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+		       PWM_CONTINUOUS,
 };
 
 static const struct rockchip_pwm_data pwm_data_vop = {
@@ -310,15 +269,30 @@ static const struct rockchip_pwm_data pwm_data_vop = {
 	},
 	.prescaler = 1,
 	.supports_polarity = true,
-	.ops = &rockchip_pwm_ops_v2,
-	.set_enable = rockchip_pwm_set_enable_v2,
-	.get_state = rockchip_pwm_get_state_v2,
+	.supports_lock = false,
+	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+		       PWM_CONTINUOUS,
+};
+
+static const struct rockchip_pwm_data pwm_data_v3 = {
+	.regs = {
+		.duty = 0x08,
+		.period = 0x04,
+		.cntr = 0x00,
+		.ctrl = 0x0c,
+	},
+	.prescaler = 1,
+	.supports_polarity = true,
+	.supports_lock = true,
+	.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+		       PWM_CONTINUOUS,
 };
 
 static const struct of_device_id rockchip_pwm_dt_ids[] = {
 	{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
 	{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
 	{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
+	{ .compatible = "rockchip,rk3328-pwm", .data = &pwm_data_v3},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
@@ -328,7 +302,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
 	const struct of_device_id *id;
 	struct rockchip_pwm_chip *pc;
 	struct resource *r;
-	int ret;
+	int ret, count;
 
 	id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
 	if (!id)
@@ -343,19 +317,49 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
 	if (IS_ERR(pc->base))
 		return PTR_ERR(pc->base);
 
-	pc->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(pc->clk))
-		return PTR_ERR(pc->clk);
+	pc->clk = devm_clk_get(&pdev->dev, "pwm");
+	if (IS_ERR(pc->clk)) {
+		pc->clk = devm_clk_get(&pdev->dev, NULL);
+		if (IS_ERR(pc->clk)) {
+			ret = PTR_ERR(pc->clk);
+			if (ret != -EPROBE_DEFER)
+				dev_err(&pdev->dev, "Can't get bus clk: %d\n",
+					ret);
+			return ret;
+		}
+	}
+
+	count = of_count_phandle_with_args(pdev->dev.of_node,
+					   "clocks", "#clock-cells");
+	if (count == 2)
+		pc->pclk = devm_clk_get(&pdev->dev, "pclk");
+	else
+		pc->pclk = pc->clk;
+
+	if (IS_ERR(pc->pclk)) {
+		ret = PTR_ERR(pc->pclk);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Can't get APB clk: %d\n", ret);
+		return ret;
+	}
 
 	ret = clk_prepare_enable(pc->clk);
-	if (ret)
+	if (ret) {
+		dev_err(&pdev->dev, "Can't prepare enable bus clk: %d\n", ret);
 		return ret;
+	}
+
+	ret = clk_prepare(pc->pclk);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't prepare APB clk: %d\n", ret);
+		goto err_clk;
+	}
 
 	platform_set_drvdata(pdev, pc);
 
 	pc->data = id->data;
 	pc->chip.dev = &pdev->dev;
-	pc->chip.ops = pc->data->ops;
+	pc->chip.ops = &rockchip_pwm_ops;
 	pc->chip.base = -1;
 	pc->chip.npwm = 1;
 
@@ -368,12 +372,20 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
 	if (ret < 0) {
 		clk_unprepare(pc->clk);
 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+		goto err_pclk;
 	}
 
 	/* Keep the PWM clk enabled if the PWM appears to be up and running. */
 	if (!pwm_is_enabled(pc->chip.pwms))
 		clk_disable(pc->clk);
 
+	return 0;
+
+err_pclk:
+	clk_unprepare(pc->pclk);
+err_clk:
+	clk_disable_unprepare(pc->clk);
+
 	return ret;
 }
 
@@ -395,6 +407,7 @@ static int rockchip_pwm_remove(struct platform_device *pdev)
 	if (pwm_is_enabled(pc->chip.pwms))
 		clk_disable(pc->clk);
 
+	clk_unprepare(pc->pclk);
 	clk_unprepare(pc->clk);
 
 	return pwmchip_remove(&pc->chip);

drivers/pwm/pwm-samsung.c

@@ -3,6 +3,7 @@
  * Copyright (c) 2008 Simtec Electronics
  *     Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
  * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
+ * Copyright (c) 2017 Samsung Electronics Co., Ltd.
  *
  * PWM driver for Samsung SoCs
  *
@@ -74,6 +75,7 @@ struct samsung_pwm_channel {
  * @chip:		generic PWM chip
  * @variant:		local copy of hardware variant data
  * @inverter_mask:	inverter status for all channels - one bit per channel
+ * @disabled_mask:	disabled status for all channels - one bit per channel
  * @base:		base address of mapped PWM registers
  * @base_clk:		base clock used to drive the timers
  * @tclk0:		external clock 0 (can be ERR_PTR if not present)
@@ -83,6 +85,7 @@ struct samsung_pwm_chip {
 	struct pwm_chip chip;
 	struct samsung_pwm_variant variant;
 	u8 inverter_mask;
+	u8 disabled_mask;
 
 	void __iomem *base;
 	struct clk *base_clk;
@@ -257,6 +260,8 @@ static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	tcon |= TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan);
 	writel(tcon, our_chip->base + REG_TCON);
 
+	our_chip->disabled_mask &= ~BIT(pwm->hwpwm);
+
 	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
 
 	return 0;
@@ -275,6 +280,8 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	tcon &= ~TCON_AUTORELOAD(tcon_chan);
 	writel(tcon, our_chip->base + REG_TCON);
 
+	our_chip->disabled_mask |= BIT(pwm->hwpwm);
+
 	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
 }
 
@@ -297,8 +304,8 @@ static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
 	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
 }
 
-static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
-			      int duty_ns, int period_ns)
+static int __pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
+				int duty_ns, int period_ns, bool force_period)
 {
 	struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
 	struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
@@ -312,9 +319,6 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	if (period_ns > NSEC_PER_SEC)
 		return -ERANGE;
 
-	if (period_ns == chan->period_ns && duty_ns == chan->duty_ns)
-		return 0;
-
 	tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));
 	oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm));
 
@@ -322,7 +326,7 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	++tcnt;
 
 	/* Check to see if we are changing the clock rate of the PWM. */
-	if (chan->period_ns != period_ns) {
+	if (chan->period_ns != period_ns || force_period) {
 		unsigned long tin_rate;
 		u32 period;
 
@@ -381,6 +385,12 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	return 0;
 }
 
+static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			      int duty_ns, int period_ns)
+{
+	return __pwm_samsung_config(chip, pwm, duty_ns, period_ns, false);
+}
+
 static void pwm_samsung_set_invert(struct samsung_pwm_chip *chip,
 				   unsigned int channel, bool invert)
 {
@@ -592,51 +602,41 @@ static int pwm_samsung_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_SLEEP
-static int pwm_samsung_suspend(struct device *dev)
+static int pwm_samsung_resume(struct device *dev)
 {
-	struct samsung_pwm_chip *chip = dev_get_drvdata(dev);
+	struct samsung_pwm_chip *our_chip = dev_get_drvdata(dev);
+	struct pwm_chip *chip = &our_chip->chip;
 	unsigned int i;
 
-	/*
-	 * No one preserves these values during suspend so reset them.
-	 * Otherwise driver leaves PWM unconfigured if same values are
-	 * passed to pwm_config() next time.
-	 */
-	for (i = 0; i < SAMSUNG_PWM_NUM; ++i) {
-		struct pwm_device *pwm = &chip->chip.pwms[i];
+	for (i = 0; i < SAMSUNG_PWM_NUM; i++) {
+		struct pwm_device *pwm = &chip->pwms[i];
 		struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
 
 		if (!chan)
 			continue;
 
-		chan->period_ns = 0;
-		chan->duty_ns = 0;
-	}
-
-	return 0;
-}
+		if (our_chip->variant.output_mask & BIT(i))
+			pwm_samsung_set_invert(our_chip, i,
+					our_chip->inverter_mask & BIT(i));
 
-static int pwm_samsung_resume(struct device *dev)
-{
-	struct samsung_pwm_chip *chip = dev_get_drvdata(dev);
-	unsigned int chan;
+		if (chan->period_ns) {
+			__pwm_samsung_config(chip, pwm, chan->duty_ns,
+					     chan->period_ns, true);
+			/* needed to make PWM disable work on Odroid-XU3 */
+			pwm_samsung_manual_update(our_chip, pwm);
+		}
 
-	/*
-	 * Inverter setting must be preserved across suspend/resume
-	 * as nobody really seems to configure it more than once.
-	 */
-	for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan) {
-		if (chip->variant.output_mask & BIT(chan))
-			pwm_samsung_set_invert(chip, chan,
-					chip->inverter_mask & BIT(chan));
+		if (our_chip->disabled_mask & BIT(i))
+			pwm_samsung_disable(chip, pwm);
+		else
+			pwm_samsung_enable(chip, pwm);
 	}
 
 	return 0;
 }
 #endif
 
-static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, pwm_samsung_suspend,
-			 pwm_samsung_resume);
+static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume);
 
 static struct platform_driver pwm_samsung_driver = {
 	.driver		= {

drivers/pwm/pwm-tegra.c

@@ -218,7 +218,7 @@ static int tegra_pwm_probe(struct platform_device *pdev)
 	 */
 	pwm->clk_rate = clk_get_rate(pwm->clk);
 
-	pwm->rst = devm_reset_control_get(&pdev->dev, "pwm");
+	pwm->rst = devm_reset_control_get_exclusive(&pdev->dev, "pwm");
 	if (IS_ERR(pwm->rst)) {
 		ret = PTR_ERR(pwm->rst);
 		dev_err(&pdev->dev, "Reset control is not found: %d\n", ret);

drivers/pwm/pwm-tiecap.c

@@ -39,15 +39,15 @@
 #define ECCTL2_TSCTR_FREERUN	BIT(4)
 
 struct ecap_context {
-	u32	cap3;
-	u32	cap4;
-	u16	ecctl2;
+	u32 cap3;
+	u32 cap4;
+	u16 ecctl2;
 };
 
 struct ecap_pwm_chip {
-	struct pwm_chip	chip;
-	unsigned int	clk_rate;
-	void __iomem	*mmio_base;
+	struct pwm_chip chip;
+	unsigned int clk_rate;
+	void __iomem *mmio_base;
 	struct ecap_context ctx;
 };
 
@@ -64,9 +64,9 @@ 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);
+	u32 period_cycles, duty_cycles;
 	unsigned long long c;
-	unsigned long period_cycles, duty_cycles;
-	unsigned int reg_val;
+	u16 value;
 
 	if (period_ns > NSEC_PER_SEC)
 		return -ERANGE;
@@ -74,7 +74,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	c = pc->clk_rate;
 	c = c * period_ns;
 	do_div(c, NSEC_PER_SEC);
-	period_cycles = (unsigned long)c;
+	period_cycles = (u32)c;
 
 	if (period_cycles < 1) {
 		period_cycles = 1;
@@ -83,17 +83,17 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		c = pc->clk_rate;
 		c = c * duty_ns;
 		do_div(c, NSEC_PER_SEC);
-		duty_cycles = (unsigned long)c;
+		duty_cycles = (u32)c;
 	}
 
 	pm_runtime_get_sync(pc->chip.dev);
 
-	reg_val = readw(pc->mmio_base + ECCTL2);
+	value = readw(pc->mmio_base + ECCTL2);
 
 	/* Configure APWM mode & disable sync option */
-	reg_val |= ECCTL2_APWM_MODE | ECCTL2_SYNC_SEL_DISA;
+	value |= ECCTL2_APWM_MODE | ECCTL2_SYNC_SEL_DISA;
 
-	writew(reg_val, pc->mmio_base + ECCTL2);
+	writew(value, pc->mmio_base + ECCTL2);
 
 	if (!pwm_is_enabled(pwm)) {
 		/* Update active registers if not running */
@@ -110,40 +110,45 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	}
 
 	if (!pwm_is_enabled(pwm)) {
-		reg_val = readw(pc->mmio_base + ECCTL2);
+		value = 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);
+		value &= ~ECCTL2_APWM_MODE;
+		writew(value, 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)
+				 enum pwm_polarity polarity)
 {
 	struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
-	unsigned short reg_val;
+	u16 value;
 
 	pm_runtime_get_sync(pc->chip.dev);
-	reg_val = readw(pc->mmio_base + ECCTL2);
+
+	value = readw(pc->mmio_base + ECCTL2);
+
 	if (polarity == PWM_POLARITY_INVERSED)
 		/* Duty cycle defines LOW period of PWM */
-		reg_val |= ECCTL2_APWM_POL_LOW;
+		value |= ECCTL2_APWM_POL_LOW;
 	else
 		/* Duty cycle defines HIGH period of PWM */
-		reg_val &= ~ECCTL2_APWM_POL_LOW;
+		value &= ~ECCTL2_APWM_POL_LOW;
+
+	writew(value, pc->mmio_base + ECCTL2);
 
-	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;
+	u16 value;
 
 	/* Leave clock enabled on enabling PWM */
 	pm_runtime_get_sync(pc->chip.dev);
@@ -152,24 +157,25 @@ static int ecap_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	 * 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);
+	value = readw(pc->mmio_base + ECCTL2);
+	value |= ECCTL2_TSCTR_FREERUN | ECCTL2_APWM_MODE;
+	writew(value, 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;
+	u16 value;
 
 	/*
 	 * 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);
+	value = readw(pc->mmio_base + ECCTL2);
+	value &= ~(ECCTL2_TSCTR_FREERUN | ECCTL2_APWM_MODE);
+	writew(value, pc->mmio_base + ECCTL2);
 
 	/* Disable clock on PWM disable */
 	pm_runtime_put_sync(pc->chip.dev);
@@ -184,12 +190,12 @@ static void ecap_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 }
 
 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,
+	.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[] = {
@@ -202,10 +208,10 @@ MODULE_DEVICE_TABLE(of, ecap_of_match);
 static int ecap_pwm_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
-	int ret;
+	struct ecap_pwm_chip *pc;
 	struct resource *r;
 	struct clk *clk;
-	struct ecap_pwm_chip *pc;
+	int ret;
 
 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
 	if (!pc)
@@ -248,9 +254,9 @@ static int ecap_pwm_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	platform_set_drvdata(pdev, pc);
 	pm_runtime_enable(&pdev->dev);
 
-	platform_set_drvdata(pdev, pc);
 	return 0;
 }
 
@@ -259,6 +265,7 @@ static int ecap_pwm_remove(struct platform_device *pdev)
 	struct ecap_pwm_chip *pc = platform_get_drvdata(pdev);
 
 	pm_runtime_disable(&pdev->dev);
+
 	return pwmchip_remove(&pc->chip);
 }
 
@@ -311,14 +318,13 @@ 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",
+		.name = "ecap",
 		.of_match_table = ecap_of_match,
-		.pm	= &ecap_pwm_pm_ops,
+		.pm = &ecap_pwm_pm_ops,
 	},
 	.probe = ecap_pwm_probe,
 	.remove = ecap_pwm_remove,
 };
-
 module_platform_driver(ecap_pwm_driver);
 
 MODULE_DESCRIPTION("ECAP PWM driver");

drivers/pwm/pwm-tiehrpwm.c

@@ -122,12 +122,12 @@ struct ehrpwm_context {
 };
 
 struct ehrpwm_pwm_chip {
-	struct pwm_chip	chip;
-	unsigned int	clk_rate;
-	void __iomem	*mmio_base;
+	struct pwm_chip chip;
+	unsigned long clk_rate;
+	void __iomem *mmio_base;
 	unsigned long period_cycles[NUM_PWM_CHANNEL];
 	enum pwm_polarity polarity[NUM_PWM_CHANNEL];
-	struct	clk	*tbclk;
+	struct clk *tbclk;
 	struct ehrpwm_context ctx;
 };
 
@@ -136,25 +136,26 @@ static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
 	return container_of(chip, struct ehrpwm_pwm_chip, chip);
 }
 
-static inline u16 ehrpwm_read(void __iomem *base, int offset)
+static inline u16 ehrpwm_read(void __iomem *base, unsigned int offset)
 {
 	return readw(base + offset);
 }
 
-static inline void ehrpwm_write(void __iomem *base, int offset, unsigned int val)
+static inline void ehrpwm_write(void __iomem *base, unsigned int offset,
+				u16 value)
 {
-	writew(val & 0xFFFF, base + offset);
+	writew(value, base + offset);
 }
 
-static void ehrpwm_modify(void __iomem *base, int offset,
-		unsigned short mask, unsigned short val)
+static void ehrpwm_modify(void __iomem *base, unsigned int offset, u16 mask,
+			  u16 value)
 {
-	unsigned short regval;
+	unsigned short val;
 
-	regval = readw(base + offset);
-	regval &= ~mask;
-	regval |= val & mask;
-	writew(regval, base + offset);
+	val = readw(base + offset);
+	val &= ~mask;
+	val |= value & mask;
+	writew(val, base + offset);
 }
 
 /**
@@ -163,14 +164,13 @@ static void ehrpwm_modify(void __iomem *base, int offset,
  * @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)
+static int set_prescale_div(unsigned long rqst_prescaler, u16 *prescale_div,
+			    u16 *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.
@@ -191,13 +191,14 @@ static int set_prescale_div(unsigned long rqst_prescaler,
 			}
 		}
 	}
+
 	return 1;
 }
 
 static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
 {
-	int aqctl_reg;
-	unsigned short aqctl_val, aqctl_mask;
+	u16 aqctl_val, aqctl_mask;
+	unsigned int aqctl_reg;
 
 	/*
 	 * Configure PWM output to HIGH/LOW level on counter
@@ -232,13 +233,13 @@ static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
  * 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)
+			     int duty_ns, int period_ns)
 {
 	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+	u32 period_cycles, duty_cycles;
+	u16 ps_divval, tb_divval;
+	unsigned int i, cmp_reg;
 	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;
@@ -272,8 +273,9 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 			if (i == pwm->hwpwm)
 				continue;
 
-			dev_err(chip->dev, "Period value conflicts with channel %d\n",
-					i);
+			dev_err(chip->dev,
+				"period value conflicts with channel %u\n",
+				i);
 			return -EINVAL;
 		}
 	}
@@ -282,7 +284,7 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	/* Configure clock prescaler to support Low frequency PWM wave */
 	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
-				&tb_divval)) {
+			     &tb_divval)) {
 		dev_err(chip->dev, "Unsupported values\n");
 		return -EINVAL;
 	}
@@ -303,7 +305,7 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	/* Configure ehrpwm counter for up-count mode */
 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
-			TBCTL_CTRMODE_UP);
+		      TBCTL_CTRMODE_UP);
 
 	if (pwm->hwpwm == 1)
 		/* Channel 1 configured with compare B register */
@@ -315,23 +317,26 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	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 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;
+	u16 aqcsfrc_val, aqcsfrc_mask;
 	int ret;
 
 	/* Leave clock enabled on enabling PWM */
@@ -348,7 +353,7 @@ static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 	/* Changes to shadow mode */
 	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
-			AQSFRC_RLDCSF_ZRO);
+		      AQSFRC_RLDCSF_ZRO);
 
 	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
 
@@ -358,20 +363,21 @@ static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	/* Enable TBCLK before enabling PWM device */
 	ret = clk_enable(pc->tbclk);
 	if (ret) {
-		dev_err(chip->dev, "Failed to enable TBCLK for %s\n",
-			dev_name(pc->chip.dev));
+		dev_err(chip->dev, "Failed to enable TBCLK for %s: %d\n",
+			dev_name(pc->chip.dev), ret);
 		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;
+	u16 aqcsfrc_val, aqcsfrc_mask;
 
 	/* Action Qualifier puts PWM output low forcefully */
 	if (pwm->hwpwm) {
@@ -387,7 +393,7 @@ static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	 * Action Qualifier control on PWM output from next TBCLK
 	 */
 	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
-			AQSFRC_RLDCSF_IMDT);
+		      AQSFRC_RLDCSF_IMDT);
 
 	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
 
@@ -415,17 +421,17 @@ static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 }
 
 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,
+	.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,am3352-ehrpwm" },
-	{ .compatible	= "ti,am33xx-ehrpwm" },
+	{ .compatible = "ti,am3352-ehrpwm" },
+	{ .compatible = "ti,am33xx-ehrpwm" },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
@@ -433,10 +439,10 @@ MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
 static int ehrpwm_pwm_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
-	int ret;
+	struct ehrpwm_pwm_chip *pc;
 	struct resource *r;
 	struct clk *clk;
-	struct ehrpwm_pwm_chip *pc;
+	int ret;
 
 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
 	if (!pc)
@@ -489,13 +495,18 @@ static int ehrpwm_pwm_probe(struct platform_device *pdev)
 	ret = pwmchip_add(&pc->chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
-		return ret;
+		goto err_clk_unprepare;
 	}
 
+	platform_set_drvdata(pdev, pc);
 	pm_runtime_enable(&pdev->dev);
 
-	platform_set_drvdata(pdev, pc);
 	return 0;
+
+err_clk_unprepare:
+	clk_unprepare(pc->tbclk);
+
+	return ret;
 }
 
 static int ehrpwm_pwm_remove(struct platform_device *pdev)
@@ -504,8 +515,8 @@ static int ehrpwm_pwm_remove(struct platform_device *pdev)
 
 	clk_unprepare(pc->tbclk);
 
-	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+
 	return pwmchip_remove(&pc->chip);
 }
 
@@ -513,6 +524,7 @@ static int ehrpwm_pwm_remove(struct platform_device *pdev)
 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);
@@ -521,6 +533,7 @@ static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
 	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);
 }
 
@@ -539,9 +552,10 @@ static void ehrpwm_pwm_restore_context(struct ehrpwm_pwm_chip *pc)
 static int ehrpwm_pwm_suspend(struct device *dev)
 {
 	struct ehrpwm_pwm_chip *pc = dev_get_drvdata(dev);
-	int i;
+	unsigned int i;
 
 	ehrpwm_pwm_save_context(pc);
+
 	for (i = 0; i < pc->chip.npwm; i++) {
 		struct pwm_device *pwm = &pc->chip.pwms[i];
 
@@ -551,13 +565,14 @@ static int ehrpwm_pwm_suspend(struct device *dev)
 		/* 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;
+	unsigned int i;
 
 	for (i = 0; i < pc->chip.npwm; i++) {
 		struct pwm_device *pwm = &pc->chip.pwms[i];
@@ -568,24 +583,25 @@ static int ehrpwm_pwm_resume(struct device *dev)
 		/* 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);
+			 ehrpwm_pwm_resume);
 
 static struct platform_driver ehrpwm_pwm_driver = {
 	.driver = {
-		.name	= "ehrpwm",
+		.name = "ehrpwm",
 		.of_match_table = ehrpwm_of_match,
-		.pm	= &ehrpwm_pwm_pm_ops,
+		.pm = &ehrpwm_pwm_pm_ops,
 	},
 	.probe = ehrpwm_pwm_probe,
 	.remove = ehrpwm_pwm_remove,
 };
-
 module_platform_driver(ehrpwm_pwm_driver);
 
 MODULE_DESCRIPTION("EHRPWM PWM driver");

drivers/pwm/pwm-vt8500.c

@@ -241,6 +241,7 @@ static int vt8500_pwm_probe(struct platform_device *pdev)
 	ret = pwmchip_add(&chip->chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed to add PWM chip\n");
+		clk_unprepare(chip->clk);
 		return ret;
 	}
 

drivers/pwm/pwm-zx.c

+/*
+ * Copyright (C) 2017 Sanechips Technology Co., Ltd.
+ * Copyright 2017 Linaro Ltd.
+ *
+ * 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/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+#define ZX_PWM_MODE		0x0
+#define ZX_PWM_CLKDIV_SHIFT	2
+#define ZX_PWM_CLKDIV_MASK	GENMASK(11, 2)
+#define ZX_PWM_CLKDIV(x)	(((x) << ZX_PWM_CLKDIV_SHIFT) & \
+					 ZX_PWM_CLKDIV_MASK)
+#define ZX_PWM_POLAR		BIT(1)
+#define ZX_PWM_EN		BIT(0)
+#define ZX_PWM_PERIOD		0x4
+#define ZX_PWM_DUTY		0x8
+
+#define ZX_PWM_CLKDIV_MAX	1023
+#define ZX_PWM_PERIOD_MAX	65535
+
+struct zx_pwm_chip {
+	struct pwm_chip chip;
+	struct clk *pclk;
+	struct clk *wclk;
+	void __iomem *base;
+};
+
+static inline struct zx_pwm_chip *to_zx_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct zx_pwm_chip, chip);
+}
+
+static inline u32 zx_pwm_readl(struct zx_pwm_chip *zpc, unsigned int hwpwm,
+			       unsigned int offset)
+{
+	return readl(zpc->base + (hwpwm + 1) * 0x10 + offset);
+}
+
+static inline void zx_pwm_writel(struct zx_pwm_chip *zpc, unsigned int hwpwm,
+				 unsigned int offset, u32 value)
+{
+	writel(value, zpc->base + (hwpwm + 1) * 0x10 + offset);
+}
+
+static void zx_pwm_set_mask(struct zx_pwm_chip *zpc, unsigned int hwpwm,
+			    unsigned int offset, u32 mask, u32 value)
+{
+	u32 data;
+
+	data = zx_pwm_readl(zpc, hwpwm, offset);
+	data &= ~mask;
+	data |= value & mask;
+	zx_pwm_writel(zpc, hwpwm, offset, data);
+}
+
+static void zx_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+			     struct pwm_state *state)
+{
+	struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
+	unsigned long rate;
+	unsigned int div;
+	u32 value;
+	u64 tmp;
+
+	value = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_MODE);
+
+	if (value & ZX_PWM_POLAR)
+		state->polarity = PWM_POLARITY_NORMAL;
+	else
+		state->polarity = PWM_POLARITY_INVERSED;
+
+	if (value & ZX_PWM_EN)
+		state->enabled = true;
+	else
+		state->enabled = false;
+
+	div = (value & ZX_PWM_CLKDIV_MASK) >> ZX_PWM_CLKDIV_SHIFT;
+	rate = clk_get_rate(zpc->wclk);
+
+	tmp = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_PERIOD);
+	tmp *= div * NSEC_PER_SEC;
+	state->period = DIV_ROUND_CLOSEST_ULL(tmp, rate);
+
+	tmp = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_DUTY);
+	tmp *= div * NSEC_PER_SEC;
+	state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, rate);
+}
+
+static int zx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+			 unsigned int duty_ns, unsigned int period_ns)
+{
+	struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
+	unsigned int period_cycles, duty_cycles;
+	unsigned long long c;
+	unsigned int div = 1;
+	unsigned long rate;
+
+	/* Find out the best divider */
+	rate = clk_get_rate(zpc->wclk);
+
+	while (1) {
+		c = rate / div;
+		c = c * period_ns;
+		do_div(c, NSEC_PER_SEC);
+
+		if (c < ZX_PWM_PERIOD_MAX)
+			break;
+
+		div++;
+
+		if (div > ZX_PWM_CLKDIV_MAX)
+			return -ERANGE;
+	}
+
+	/* Calculate duty cycles */
+	period_cycles = c;
+	c *= duty_ns;
+	do_div(c, period_ns);
+	duty_cycles = c;
+
+	/*
+	 * If the PWM is being enabled, we have to temporarily disable it
+	 * before configuring the registers.
+	 */
+	if (pwm_is_enabled(pwm))
+		zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_EN, 0);
+
+	/* Set up registers */
+	zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_CLKDIV_MASK,
+			ZX_PWM_CLKDIV(div));
+	zx_pwm_writel(zpc, pwm->hwpwm, ZX_PWM_PERIOD, period_cycles);
+	zx_pwm_writel(zpc, pwm->hwpwm, ZX_PWM_DUTY, duty_cycles);
+
+	/* Re-enable the PWM if needed */
+	if (pwm_is_enabled(pwm))
+		zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
+				ZX_PWM_EN, ZX_PWM_EN);
+
+	return 0;
+}
+
+static int zx_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			struct pwm_state *state)
+{
+	struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
+	struct pwm_state cstate;
+	int ret;
+
+	pwm_get_state(pwm, &cstate);
+
+	if (state->polarity != cstate.polarity)
+		zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_POLAR,
+				(state->polarity == PWM_POLARITY_INVERSED) ?
+				 0 : ZX_PWM_POLAR);
+
+	if (state->period != cstate.period ||
+	    state->duty_cycle != cstate.duty_cycle) {
+		ret = zx_pwm_config(chip, pwm, state->duty_cycle,
+				    state->period);
+		if (ret)
+			return ret;
+	}
+
+	if (state->enabled != cstate.enabled) {
+		if (state->enabled) {
+			ret = clk_prepare_enable(zpc->wclk);
+			if (ret)
+				return ret;
+
+			zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
+					ZX_PWM_EN, ZX_PWM_EN);
+		} else {
+			zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
+					ZX_PWM_EN, 0);
+			clk_disable_unprepare(zpc->wclk);
+		}
+	}
+
+	return 0;
+}
+
+static const struct pwm_ops zx_pwm_ops = {
+	.apply = zx_pwm_apply,
+	.get_state = zx_pwm_get_state,
+	.owner = THIS_MODULE,
+};
+
+static int zx_pwm_probe(struct platform_device *pdev)
+{
+	struct zx_pwm_chip *zpc;
+	struct resource *res;
+	unsigned int i;
+	int ret;
+
+	zpc = devm_kzalloc(&pdev->dev, sizeof(*zpc), GFP_KERNEL);
+	if (!zpc)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	zpc->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(zpc->base))
+		return PTR_ERR(zpc->base);
+
+	zpc->pclk = devm_clk_get(&pdev->dev, "pclk");
+	if (IS_ERR(zpc->pclk))
+		return PTR_ERR(zpc->pclk);
+
+	zpc->wclk = devm_clk_get(&pdev->dev, "wclk");
+	if (IS_ERR(zpc->wclk))
+		return PTR_ERR(zpc->wclk);
+
+	ret = clk_prepare_enable(zpc->pclk);
+	if (ret)
+		return ret;
+
+	zpc->chip.dev = &pdev->dev;
+	zpc->chip.ops = &zx_pwm_ops;
+	zpc->chip.base = -1;
+	zpc->chip.npwm = 4;
+	zpc->chip.of_xlate = of_pwm_xlate_with_flags;
+	zpc->chip.of_pwm_n_cells = 3;
+
+	/*
+	 * PWM devices may be enabled by firmware, and let's disable all of
+	 * them initially to save power.
+	 */
+	for (i = 0; i < zpc->chip.npwm; i++)
+		zx_pwm_set_mask(zpc, i, ZX_PWM_MODE, ZX_PWM_EN, 0);
+
+	ret = pwmchip_add(&zpc->chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, zpc);
+
+	return 0;
+}
+
+static int zx_pwm_remove(struct platform_device *pdev)
+{
+	struct zx_pwm_chip *zpc = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = pwmchip_remove(&zpc->chip);
+	clk_disable_unprepare(zpc->pclk);
+
+	return ret;
+}
+
+static const struct of_device_id zx_pwm_dt_ids[] = {
+	{ .compatible = "zte,zx296718-pwm", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, zx_pwm_dt_ids);
+
+static struct platform_driver zx_pwm_driver = {
+	.driver = {
+		.name = "zx-pwm",
+		.of_match_table = zx_pwm_dt_ids,
+	},
+	.probe = zx_pwm_probe,
+	.remove = zx_pwm_remove,
+};
+module_platform_driver(zx_pwm_driver);
+
+MODULE_ALIAS("platform:zx-pwm");
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_DESCRIPTION("ZTE ZX PWM Driver");
+MODULE_LICENSE("GPL v2");