[PATCH v3 1/6] leds: turris-omnia: drop unnecessary mutex locking

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Do not lock driver mutex in the global LED panel brightness sysfs
accessors brightness_show() and brightness_store().

The mutex locking is unnecessary here. The I2C transfers are guarded by
I2C core locking mechanism, and the LED commands itself do not interfere
with other commands.

Fixes: 089381b27abe ("leds: initial support for Turris Omnia LEDs")
Signed-off-by: Marek Behún <kabel@xxxxxxxxxx>
---
 drivers/leds/leds-turris-omnia.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c
index 64b2d7b6d3f3..bbd610100e41 100644
--- a/drivers/leds/leds-turris-omnia.c
+++ b/drivers/leds/leds-turris-omnia.c
@@ -156,12 +156,9 @@ static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
 			       char *buf)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	struct omnia_leds *leds = i2c_get_clientdata(client);
 	int ret;
 
-	mutex_lock(&leds->lock);
 	ret = i2c_smbus_read_byte_data(client, CMD_LED_GET_BRIGHTNESS);
-	mutex_unlock(&leds->lock);
 
 	if (ret < 0)
 		return ret;
@@ -173,7 +170,6 @@ static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
 				const char *buf, size_t count)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	struct omnia_leds *leds = i2c_get_clientdata(client);
 	unsigned long brightness;
 	int ret;
 
@@ -183,15 +179,10 @@ static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
 	if (brightness > 100)
 		return -EINVAL;
 
-	mutex_lock(&leds->lock);
 	ret = i2c_smbus_write_byte_data(client, CMD_LED_SET_BRIGHTNESS,
 					(u8)brightness);
-	mutex_unlock(&leds->lock);
-
-	if (ret < 0)
-		return ret;
 
-	return count;
+	return ret < 0 ? ret : count;
 }
 static DEVICE_ATTR_RW(brightness);
 
-- 
2.41.0




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux