drivers/video/backlight/lp855x_bl.c: remove unnecessary mutex code
The mutex for accessing lp855x registers is used in case of the user-space
interaction. When the brightness is changed via 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.kim@ti.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index b437541..6e4db0c 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -35,7 +35,6 @@
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 @@
{
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_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)
@@ -281,8 +271,6 @@
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);