[PATCH] backlight: lcd: return ENXIO when ops functions cannot becalled

From: Jingoo Han
Date: Fri Nov 16 2012 - 03:36:14 EST


Previously, when ops functions cannot be called,
lcd_show_contrast() and lcd_store_contrast() returned 0,
instead of ENXIO.

Thus, in this case, a local variable 'rc' for return value
should be initialized as ENXIO, after kstrtoul() is called.

Signed-off-by: Jingoo Han <jg1.han@xxxxxxxxxxx>
Cc: Richard Purdie <rpurdie@xxxxxxxxx>
---
drivers/video/backlight/lcd.c | 8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
index a5d0d02..34fb6bd 100644
--- a/drivers/video/backlight/lcd.c
+++ b/drivers/video/backlight/lcd.c
@@ -108,7 +108,7 @@ static ssize_t lcd_show_power(struct device *dev, struct device_attribute *attr,
static ssize_t lcd_store_power(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
- int rc = -ENXIO;
+ int rc;
struct lcd_device *ld = to_lcd_device(dev);
unsigned long power;

@@ -116,6 +116,8 @@ static ssize_t lcd_store_power(struct device *dev,
if (rc)
return rc;

+ rc = -ENXIO;
+
mutex_lock(&ld->ops_lock);
if (ld->ops && ld->ops->set_power) {
pr_debug("set power to %lu\n", power);
@@ -144,7 +146,7 @@ static ssize_t lcd_show_contrast(struct device *dev,
static ssize_t lcd_store_contrast(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
- int rc = -ENXIO;
+ int rc;
struct lcd_device *ld = to_lcd_device(dev);
unsigned long contrast;

@@ -152,6 +154,8 @@ static ssize_t lcd_store_contrast(struct device *dev,
if (rc)
return rc;

+ rc = -ENXIO;
+
mutex_lock(&ld->ops_lock);
if (ld->ops && ld->ops->set_contrast) {
pr_debug("set contrast to %lu\n", contrast);
--
1.7.2.5


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