diff options
| -rw-r--r-- | src/backlight/backlight.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/src/backlight/backlight.c b/src/backlight/backlight.c index 691472cc3a..4d94ebf58a 100644 --- a/src/backlight/backlight.c +++ b/src/backlight/backlight.c @@ -225,11 +225,13 @@ static unsigned get_max_brightness(struct udev_device *device) { /* Some systems turn the backlight all the way off at the lowest levels. * clamp_brightness clamps the saved brightness to at least 1 or 5% of - * max_brightness. This avoids preserving an unreadably dim screen, which - * would otherwise force the user to disable state restoration. */ + * max_brightness in case of 'backlight' subsystem. This avoids preserving + * an unreadably dim screen, which would otherwise force the user to + * disable state restoration. */ static void clamp_brightness(struct udev_device *device, char **value, unsigned max_brightness) { int r; unsigned brightness, new_brightness, min_brightness; + const char *subsystem; r = safe_atou(*value, &brightness); if (r < 0) { @@ -237,7 +239,12 @@ static void clamp_brightness(struct udev_device *device, char **value, unsigned return; } - min_brightness = MAX(1U, max_brightness/20); + subsystem = udev_device_get_subsystem(device); + if (streq_ptr(subsystem, "backlight")) + min_brightness = MAX(1U, max_brightness/20); + else + min_brightness = 0; + new_brightness = CLAMP(brightness, min_brightness, max_brightness); if (new_brightness != brightness) { char *old_value = *value; |