The mutex for accessing lp855x registers is used in case of
 the user-space interaction.
 When the brightness is changed via the sysfs, the mutex is required.
 But the backlight class device already provides it.
 Thus, the lp855x mutex is unnecessary.

Signed-off-by: Milo(Woogyom) Kim <milo....@ti.com>
---
 drivers/video/backlight/lp855x_bl.c |   14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/video/backlight/lp855x_bl.c 
b/drivers/video/backlight/lp855x_bl.c
index c4fd72f..ff86531 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -35,7 +35,6 @@ struct lp855x {
        struct i2c_client *client;
        struct backlight_device *bl;
        struct device *dev;
-       struct mutex xfer_lock;
        struct lp855x_platform_data *pdata;
        struct pwm_device *pwm;
 };
@@ -44,14 +43,11 @@ static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 
*data)
 {
        int ret;
 
-       mutex_lock(&lp->xfer_lock);
        ret = i2c_smbus_read_byte_data(lp->client, reg);
        if (ret < 0) {
-               mutex_unlock(&lp->xfer_lock);
                dev_err(lp->dev, "failed to read 0x%.2x\n", reg);
                return ret;
        }
-       mutex_unlock(&lp->xfer_lock);
 
        *data = (u8)ret;
        return 0;
@@ -59,13 +55,7 @@ static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 
*data)
 
 static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data)
 {
-       int ret;
-
-       mutex_lock(&lp->xfer_lock);
-       ret = i2c_smbus_write_byte_data(lp->client, reg, data);
-       mutex_unlock(&lp->xfer_lock);
-
-       return ret;
+       return i2c_smbus_write_byte_data(lp->client, reg, data);
 }
 
 static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr)
@@ -278,8 +268,6 @@ static int lp855x_probe(struct i2c_client *cl, const struct 
i2c_device_id *id)
        lp->chip_id = id->driver_data;
        i2c_set_clientdata(cl, lp);
 
-       mutex_init(&lp->xfer_lock);
-
        ret = lp855x_init_registers(lp);
        if (ret) {
                dev_err(lp->dev, "i2c communication err: %d", ret);
-- 
1.7.9.5


Best Regards,
Milo


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to