summaryrefslogtreecommitdiff
path: root/drivers/video
diff options
context:
space:
mode:
authorThomas Weißschuh <linux@weissschuh.net>2021-09-07 14:47:51 +0200
committerLee Jones <lee.jones@linaro.org>2021-09-23 10:48:00 +0100
commit563edf85ce18a90dd0a7b39e279a691d937205f6 (patch)
tree488fbe262c7625113baa8425b2d86c9a82f9cc04 /drivers/video
parent33a5471f8da976bf271a1ebbd6b9d163cb0cb6aa (diff)
backlight: Propagate errors from get_brightness()
backlight.h documents "struct backlight_ops->get_brightness()" to return a negative errno on failure. So far these errors have not been handled in the backlight core. This leads to negative values being exposed through sysfs although only positive values are documented to be reported. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/backlight/backlight.c22
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index fc990e576340..4ae6fae94ac2 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -292,10 +292,13 @@ static ssize_t actual_brightness_show(struct device *dev,
struct backlight_device *bd = to_backlight_device(dev);
mutex_lock(&bd->ops_lock);
- if (bd->ops && bd->ops->get_brightness)
- rc = sprintf(buf, "%d\n", bd->ops->get_brightness(bd));
- else
+ if (bd->ops && bd->ops->get_brightness) {
+ rc = bd->ops->get_brightness(bd);
+ if (rc >= 0)
+ rc = sprintf(buf, "%d\n", rc);
+ } else {
rc = sprintf(buf, "%d\n", bd->props.brightness);
+ }
mutex_unlock(&bd->ops_lock);
return rc;
@@ -381,9 +384,18 @@ ATTRIBUTE_GROUPS(bl_device);
void backlight_force_update(struct backlight_device *bd,
enum backlight_update_reason reason)
{
+ int brightness;
+
mutex_lock(&bd->ops_lock);
- if (bd->ops && bd->ops->get_brightness)
- bd->props.brightness = bd->ops->get_brightness(bd);
+ if (bd->ops && bd->ops->get_brightness) {
+ brightness = bd->ops->get_brightness(bd);
+ if (brightness >= 0)
+ bd->props.brightness = brightness;
+ else
+ dev_err(&bd->dev,
+ "Could not update brightness from device: %pe\n",
+ ERR_PTR(brightness));
+ }
mutex_unlock(&bd->ops_lock);
backlight_generate_event(bd, reason);
}