diff options
| author | David Francis <David.Francis@amd.com> | 2018-11-06 11:06:04 -0500 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2018-11-06 14:02:06 -0500 |
| commit | 694d0775ca94beccfa8332d9284c1e8b6b19ad01 (patch) | |
| tree | 3232fb6ef6c16231410ba68395514c33b11c8fea /drivers/gpu | |
| parent | 45cf8c23f3564e3f39ae09b70b9dff24acae4a56 (diff) | |
| download | linux-694d0775ca94beccfa8332d9284c1e8b6b19ad01.tar.bz2 | |
drm/amd: Don't fail on backlight = 0
Amgpu's backlight update status function was
returning 1 (an error value) when the backlight
property was 0. This breaks users that assume
0 is a valid backlight value (which is a
correct assumption)
If the user passes in a backlight value of 0,
tell them everything is fine, then write a value of
1 to hardware.
Signed-off-by: David Francis <David.Francis@amd.com>
Bugzilla: https://bugs.freedesktop.org/108668
Fixes: 416615ea9578 ("drm/amd/display: set backlight level limit to 1")
Cc: Suresh.Guttula@amd.com
Cc: Harry.Wentland@amd.com
Cc: Samantham@posteo.net
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 67b547c64a3e..7505a33e00e1 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1573,21 +1573,23 @@ static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) { struct amdgpu_display_manager *dm = bl_get_data(bd); + /* backlight_pwm_u16_16 parameter is in unsigned 32 bit, 16 bit integer + * and 16 bit fractional, where 1.0 is max backlight value. + * bd->props.brightness is 8 bit format and needs to be converted by + * scaling via copy lower byte to upper byte of 16 bit value. + */ + uint32_t brightness = bd->props.brightness * 0x101; + /* * PWM interperts 0 as 100% rather than 0% because of HW - * limitation for level 0.So limiting minimum brightness level + * limitation for level 0. So limiting minimum brightness level * to 1. */ if (bd->props.brightness < 1) - return 1; + brightness = 0x101; - /* backlight_pwm_u16_16 parameter is in unsigned 32 bit, 16 bit integer - * and 16 bit fractional, where 1.0 is max backlight value. - * bd->props.brightness is 8 bit format and needs to be converted by - * scaling via copy lower byte to upper byte of 16 bit value. - */ if (dc_link_set_backlight_level(dm->backlight_link, - (bd->props.brightness * 0x101), 0, 0)) + brightness, 0, 0)) return 0; else return 1; |