1 files changed, 68 insertions, 86 deletions

diff --git a/drivers/pwm/pwm-iqs620a.c b/drivers/pwm/pwm-iqs620a.c
index 674f0e238ba0..13e5e138c8e9 100644
--- a/drivers/pwm/pwm-iqs620a.c
+++ b/drivers/pwm/pwm-iqs620a.c
@@ -25,37 +25,60 @@
 #include <linux/regmap.h>
 #include <linux/slab.h>
 
-#define IQS620_PWR_SETTINGS			0xD2
+#define IQS620_PWR_SETTINGS			0xd2
 #define IQS620_PWR_SETTINGS_PWM_OUT		BIT(7)
 
-#define IQS620_PWM_DUTY_CYCLE			0xD8
+#define IQS620_PWM_DUTY_CYCLE			0xd8
 
 #define IQS620_PWM_PERIOD_NS			1000000
 
 struct iqs620_pwm_private {
 	struct iqs62x_core *iqs62x;
-	struct pwm_chip chip;
+	struct device *dev;
 	struct notifier_block notifier;
 	struct mutex lock;
-	bool out_en;
-	u8 duty_val;
+	unsigned int duty_scale;
 };
 
+static inline struct iqs620_pwm_private *iqs620_pwm_from_chip(struct pwm_chip *chip)
+{
+	return pwmchip_get_drvdata(chip);
+}
+
+static int iqs620_pwm_init(struct iqs620_pwm_private *iqs620_pwm,
+			   unsigned int duty_scale)
+{
+	struct iqs62x_core *iqs62x = iqs620_pwm->iqs62x;
+	int ret;
+
+	if (!duty_scale)
+		return regmap_clear_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
+					 IQS620_PWR_SETTINGS_PWM_OUT);
+
+	ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
+			   duty_scale - 1);
+	if (ret)
+		return ret;
+
+	return regmap_set_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
+			       IQS620_PWR_SETTINGS_PWM_OUT);
+}
+
 static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 			    const struct pwm_state *state)
 {
 	struct iqs620_pwm_private *iqs620_pwm;
-	struct iqs62x_core *iqs62x;
-	int duty_scale, ret;
+	unsigned int duty_cycle;
+	unsigned int duty_scale;
+	int ret;
 
 	if (state->polarity != PWM_POLARITY_NORMAL)
-		return -ENOTSUPP;
+		return -EINVAL;
 
 	if (state->period < IQS620_PWM_PERIOD_NS)
 		return -EINVAL;
 
-	iqs620_pwm = container_of(chip, struct iqs620_pwm_private, chip);
-	iqs62x = iqs620_pwm->iqs62x;
+	iqs620_pwm = iqs620_pwm_from_chip(chip);
 
 	/*
 	 * The duty cycle generated by the device is calculated as follows:
@@ -69,73 +92,54 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * For lower duty cycles (e.g. 0), the PWM output is simply disabled to
 	 * allow an external pull-down resistor to hold the GPIO3/LTX pin low.
 	 */
-	duty_scale = state->duty_cycle * 256 / IQS620_PWM_PERIOD_NS;
-
-	mutex_lock(&iqs620_pwm->lock);
-
-	if (!state->enabled || !duty_scale) {
-		ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
-					 IQS620_PWR_SETTINGS_PWM_OUT, 0);
-		if (ret)
-			goto err_mutex;
-	}
-
-	if (duty_scale) {
-		u8 duty_val = min(duty_scale - 1, 0xFF);
-
-		ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
-				   duty_val);
-		if (ret)
-			goto err_mutex;
+	duty_cycle = min_t(u64, state->duty_cycle, IQS620_PWM_PERIOD_NS);
+	duty_scale = duty_cycle * 256 / IQS620_PWM_PERIOD_NS;
 
-		iqs620_pwm->duty_val = duty_val;
-	}
+	if (!state->enabled)
+		duty_scale = 0;
 
-	if (state->enabled && duty_scale) {
-		ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
-					 IQS620_PWR_SETTINGS_PWM_OUT, 0xFF);
-		if (ret)
-			goto err_mutex;
-	}
+	mutex_lock(&iqs620_pwm->lock);
 
-	iqs620_pwm->out_en = state->enabled;
+	ret = iqs620_pwm_init(iqs620_pwm, duty_scale);
+	if (!ret)
+		iqs620_pwm->duty_scale = duty_scale;
 
-err_mutex:
 	mutex_unlock(&iqs620_pwm->lock);
 
 	return ret;
 }
 
-static void iqs620_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
-				 struct pwm_state *state)
+static int iqs620_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+				struct pwm_state *state)
 {
 	struct iqs620_pwm_private *iqs620_pwm;
 
-	iqs620_pwm = container_of(chip, struct iqs620_pwm_private, chip);
+	iqs620_pwm = iqs620_pwm_from_chip(chip);
 
 	mutex_lock(&iqs620_pwm->lock);
 
 	/*
 	 * Since the device cannot generate a 0% duty cycle, requests to do so
 	 * cause subsequent calls to iqs620_pwm_get_state to report the output
-	 * as disabled with duty cycle equal to that which was in use prior to
-	 * the request. This is not ideal, but is the best compromise based on
+	 * as disabled. This is not ideal, but is the best compromise based on
 	 * the capabilities of the device.
 	 */
-	state->enabled = iqs620_pwm->out_en;
-	state->duty_cycle = DIV_ROUND_UP((iqs620_pwm->duty_val + 1) *
+	state->enabled = iqs620_pwm->duty_scale > 0;
+	state->duty_cycle = DIV_ROUND_UP(iqs620_pwm->duty_scale *
 					 IQS620_PWM_PERIOD_NS, 256);
 
 	mutex_unlock(&iqs620_pwm->lock);
 
 	state->period = IQS620_PWM_PERIOD_NS;
+	state->polarity = PWM_POLARITY_NORMAL;
+
+	return 0;
 }
 
 static int iqs620_pwm_notifier(struct notifier_block *notifier,
 			       unsigned long event_flags, void *context)
 {
 	struct iqs620_pwm_private *iqs620_pwm;
-	struct iqs62x_core *iqs62x;
 	int ret;
 
 	if (!(event_flags & BIT(IQS62X_EVENT_SYS_RESET)))
@@ -143,7 +147,6 @@ static int iqs620_pwm_notifier(struct notifier_block *notifier,
 
 	iqs620_pwm = container_of(notifier, struct iqs620_pwm_private,
 				  notifier);
-	iqs62x = iqs620_pwm->iqs62x;
 
 	mutex_lock(&iqs620_pwm->lock);
 
@@ -152,20 +155,12 @@ static int iqs620_pwm_notifier(struct notifier_block *notifier,
 	 * of a device reset, so nothing else is printed here unless there is
 	 * an additional failure.
 	 */
-	ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
-			   iqs620_pwm->duty_val);
-	if (ret)
-		goto err_mutex;
+	ret = iqs620_pwm_init(iqs620_pwm, iqs620_pwm->duty_scale);
 
-	ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
-				 IQS620_PWR_SETTINGS_PWM_OUT,
-				 iqs620_pwm->out_en ? 0xFF : 0);
-
-err_mutex:
 	mutex_unlock(&iqs620_pwm->lock);
 
 	if (ret) {
-		dev_err(iqs620_pwm->chip.dev,
+		dev_err(iqs620_pwm->dev,
 			"Failed to re-initialize device: %d\n", ret);
 		return NOTIFY_BAD;
 	}
@@ -176,7 +171,6 @@ err_mutex:
 static const struct pwm_ops iqs620_pwm_ops = {
 	.apply = iqs620_pwm_apply,
 	.get_state = iqs620_pwm_get_state,
-	.owner = THIS_MODULE,
 };
 
 static void iqs620_pwm_notifier_unregister(void *context)
@@ -187,38 +181,39 @@ static void iqs620_pwm_notifier_unregister(void *context)
 	ret = blocking_notifier_chain_unregister(&iqs620_pwm->iqs62x->nh,
 						 &iqs620_pwm->notifier);
 	if (ret)
-		dev_err(iqs620_pwm->chip.dev,
+		dev_err(iqs620_pwm->dev,
 			"Failed to unregister notifier: %d\n", ret);
 }
 
 static int iqs620_pwm_probe(struct platform_device *pdev)
 {
 	struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);
+	struct pwm_chip *chip;
 	struct iqs620_pwm_private *iqs620_pwm;
 	unsigned int val;
 	int ret;
 
-	iqs620_pwm = devm_kzalloc(&pdev->dev, sizeof(*iqs620_pwm), GFP_KERNEL);
-	if (!iqs620_pwm)
-		return -ENOMEM;
+	chip = devm_pwmchip_alloc(&pdev->dev, 1, sizeof(*iqs620_pwm));
+	if (IS_ERR(chip))
+		return PTR_ERR(chip);
 
-	platform_set_drvdata(pdev, iqs620_pwm);
+	iqs620_pwm = iqs620_pwm_from_chip(chip);
+	iqs620_pwm->dev = &pdev->dev;
 	iqs620_pwm->iqs62x = iqs62x;
 
 	ret = regmap_read(iqs62x->regmap, IQS620_PWR_SETTINGS, &val);
 	if (ret)
 		return ret;
-	iqs620_pwm->out_en = val & IQS620_PWR_SETTINGS_PWM_OUT;
 
-	ret = regmap_read(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE, &val);
-	if (ret)
-		return ret;
-	iqs620_pwm->duty_val = val;
+	if (val & IQS620_PWR_SETTINGS_PWM_OUT) {
+		ret = regmap_read(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE, &val);
+		if (ret)
+			return ret;
+
+		iqs620_pwm->duty_scale = val + 1;
+	}
 
-	iqs620_pwm->chip.dev = &pdev->dev;
-	iqs620_pwm->chip.ops = &iqs620_pwm_ops;
-	iqs620_pwm->chip.base = -1;
-	iqs620_pwm->chip.npwm = 1;
+	chip->ops = &iqs620_pwm_ops;
 
 	mutex_init(&iqs620_pwm->lock);
 
@@ -236,31 +231,18 @@ static int iqs620_pwm_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	ret = pwmchip_add(&iqs620_pwm->chip);
+	ret = devm_pwmchip_add(&pdev->dev, chip);
 	if (ret)
 		dev_err(&pdev->dev, "Failed to add device: %d\n", ret);
 
 	return ret;
 }
 
-static int iqs620_pwm_remove(struct platform_device *pdev)
-{
-	struct iqs620_pwm_private *iqs620_pwm = platform_get_drvdata(pdev);
-	int ret;
-
-	ret = pwmchip_remove(&iqs620_pwm->chip);
-	if (ret)
-		dev_err(&pdev->dev, "Failed to remove device: %d\n", ret);
-
-	return ret;
-}
-
 static struct platform_driver iqs620_pwm_platform_driver = {
 	.driver = {
 		.name = "iqs620a-pwm",
 	},
 	.probe = iqs620_pwm_probe,
-	.remove = iqs620_pwm_remove,
 };
 module_platform_driver(iqs620_pwm_platform_driver);