diff options
| author | Denis Tikhomirov <dvtikhomirov@gmail.com> | 2014-06-05 23:59:40 +0400 |
|---|---|---|
| committer | Lennart Poettering <lennart@poettering.net> | 2014-06-10 18:57:48 +0200 |
| commit | 4cd2b2cf8ca585d15ebc859701b346658262b5bb (patch) | |
| tree | 557a0b696d91b77493f0d580fae6d4d4adc1d9ca /src | |
| parent | 51cb9d734a182c4892a6b31f58d75489a2ca432b (diff) | |
backlight: Do not clamp brightness for LEDs
https://bugs.freedesktop.org/show_bug.cgi?id=77092
On Thu, Jun 05, 2014 at 08:37:20AM +0200, Lennart Poettering wrote:
> The patch is line-broken, please send an uncorrupted patch!
I am very sorry, I forgot that my client limits line width. I will use
mutt now on.
> clamp_brightness() clamps the brightness value to the range of the
> actual device. This is a recent addition that was added to deal with
> driver updates where the resolution is changed. I don't think this part
> should be dropped for LED devices. The clamp_brightness() call hence
> should be called unconditionally, however, internally it should use a
> different min_brightness value if something is an !backlight devices...
Thank you for explanation, this sounds very reasonable to me. Please,
see updated patch:
Diffstat (limited to 'src')
| -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; |