pwm: twl-led: Drop driver local locking

The pwm core already serializes .apply(). twl6030's .request() and .free()
are also already serialized against .apply() because there is only a single
PWM. So the mutex doesn't add any additional protection and can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/c1c7f646190f7cb2fe43b10959aa8dade80cb79e.1750788649.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>

diff --git a/drivers/pwm/pwm-twl-led.c b/drivers/pwm/pwm-twl-led.c
index 4b10a8dab31244f2daa4db2a8037363bffd91908..a555cc3be4b313d6c0ff5784011794c74c1a9af1 100644 (file)
--- a/drivers/pwm/pwm-twl-led.c
+++ b/drivers/pwm/pwm-twl-led.c
@@ -61,10 +61,6 @@
 #define TWL6040_LED_MODE_OFF   0x02
 #define TWL6040_LED_MODE_MASK  0x03
 
-struct twl_pwmled_chip {
-       struct mutex mutex;
-};
-
 static inline struct twl_pwmled_chip *to_twl(struct pwm_chip *chip)
 {
        return pwmchip_get_drvdata(chip);
@@ -106,15 +102,13 @@ static int twl4030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 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(pwmchip_parent(chip), "%s: Failed to read LEDEN\n", pwm->label);
-               goto out;
+               return ret;
        }
 
        val |= TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS);
@@ -123,23 +117,19 @@ static int twl4030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm)
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%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(pwmchip_parent(chip), "%s: Failed to read LEDEN\n", pwm->label);
-               goto out;
+               return;
        }
 
        val &= ~TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS);
@@ -147,9 +137,6 @@ static void twl4030_pwmled_disable(struct pwm_chip *chip,
        ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG);
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
-
-out:
-       mutex_unlock(&twl->mutex);
 }
 
 static int twl4030_pwmled_apply(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -209,16 +196,14 @@ static int twl6030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 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(pwmchip_parent(chip), "%s: Failed to read PWM_CTRL2\n",
                        pwm->label);
-               goto out;
+               return ret;
        }
 
        val &= ~TWL6040_LED_MODE_MASK;
@@ -228,24 +213,20 @@ static int twl6030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm)
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%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(pwmchip_parent(chip), "%s: Failed to read PWM_CTRL2\n",
                        pwm->label);
-               goto out;
+               return;
        }
 
        val &= ~TWL6040_LED_MODE_MASK;
@@ -254,9 +235,6 @@ static void twl6030_pwmled_disable(struct pwm_chip *chip,
        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
-
-out:
-       mutex_unlock(&twl->mutex);
 }
 
 static int twl6030_pwmled_apply(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -287,16 +265,14 @@ static int twl6030_pwmled_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 
 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(pwmchip_parent(chip), "%s: Failed to read PWM_CTRL2\n",
                        pwm->label);
-               goto out;
+               return ret;
        }
 
        val &= ~TWL6040_LED_MODE_MASK;
@@ -306,23 +282,19 @@ static int twl6030_pwmled_request(struct pwm_chip *chip, struct pwm_device *pwm)
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%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(pwmchip_parent(chip), "%s: Failed to read PWM_CTRL2\n",
                        pwm->label);
-               goto out;
+               return;
        }
 
        val &= ~TWL6040_LED_MODE_MASK;
@@ -331,9 +303,6 @@ static void twl6030_pwmled_free(struct pwm_chip *chip, struct pwm_device *pwm)
        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2);
        if (ret < 0)
                dev_err(pwmchip_parent(chip), "%s: Failed to free PWM\n", pwm->label);
-
-out:
-       mutex_unlock(&twl->mutex);
 }
 
 static const struct pwm_ops twl6030_pwmled_ops = {
@@ -345,7 +314,6 @@ static const struct pwm_ops twl6030_pwmled_ops = {
 static int twl_pwmled_probe(struct platform_device *pdev)
 {
        struct pwm_chip *chip;
-       struct twl_pwmled_chip *twl;
        unsigned int npwm;
        const struct pwm_ops *ops;
 
@@ -357,15 +325,12 @@ static int twl_pwmled_probe(struct platform_device *pdev)
                npwm = 1;
        }
 
-       chip = devm_pwmchip_alloc(&pdev->dev, npwm, sizeof(*twl));
+       chip = devm_pwmchip_alloc(&pdev->dev, npwm, 0);
        if (IS_ERR(chip))
                return PTR_ERR(chip);
-       twl = to_twl(chip);
 
        chip->ops = ops;
 
-       mutex_init(&twl->mutex);
-
        return devm_pwmchip_add(&pdev->dev, chip);
 }