From 424e06e3da2cbf986d7421f98b90fe5cf4b57be5 Mon Sep 17 00:00:00 2001 From: Jingoo Han Date: Mon, 17 Dec 2012 16:01:10 -0800 Subject: [PATCH] drivers/video/backlight/lcd.c: return ENXIO when ops functions cannot be called 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 Cc: Richard Purdie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/backlight/lcd.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c index a5d0d024bb92..34fb6bd798c8 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); -- 2.20.1