[AMD Public Use]
-----Original Message----- From: Takashi Iwai tiwai@suse.de Sent: Saturday, February 6, 2021 7:29 AM To: Alex Deucher alexdeucher@gmail.com Cc: Deucher, Alexander Alexander.Deucher@amd.com; Koenig, Christian Christian.Koenig@amd.com; Li, Sun peng (Leo) Sunpeng.Li@amd.com; Wentland, Harry Harry.Wentland@amd.com; Maling list - DRI developers dri-devel@lists.freedesktop.org; amd-gfx list <amd- gfx@lists.freedesktop.org> Subject: Re: [PATCH 1/2] drm/amd/display: Fix the brightness read via aux
On Fri, 05 Feb 2021 17:36:44 +0100, Alex Deucher wrote:
On Wed, Feb 3, 2021 at 7:42 AM Takashi Iwai tiwai@suse.de wrote:
The current code tries to read the brightness value via dc_link_get_backlight_level() no matter whether it's controlled via aux or not, and this results in a bogus value returned. Fix it to read the current value via dc_link_get_backlight_level_nits() for the aux.
BugLink:
https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbu
gzilla.opensuse.org%2Fshow_bug.cgi%3Fid%3D1180749&data=04%7C01 %7
Calexander.deucher%40amd.com%7Ce5579cfe56f74b572f1508d8ca9ad0ac%7 C3d
d8961fe4884e608e11a82d994e183d%7C0%7C0%7C637482113562863043%7CU nknow
n%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1ha Wwi
LCJXVCI6Mn0%3D%7C1000&sdata=HVtqM2r6oxSWd3XGGQZotO8wrvM qCTcwfq1L
2%2FeCmSE%3D&reserved=0 BugLink:
https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgi
tlab.freedesktop.org%2Fdrm%2Famd%2F-
%2Fissues%2F1438&data=04%7C0
1%7Calexander.deucher%40amd.com%7Ce5579cfe56f74b572f1508d8ca9ad0 ac%7
C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637482113562863043% 7CUnk
nown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6I k1ha
WwiLCJXVCI6Mn0%3D%7C1000&sdata=TdYgwNJ%2FvkuoDLNb9ATFb1P yznlp%2F
P8TLuYSR%2BVkNqY%3D&reserved=0 Signed-off-by: Takashi Iwai tiwai@suse.de
This looks fine to me. FWIW, I have a similar patch set here: https://nam11.safelinks.protection.outlook.com/?url=https:%2F%2Fcgit.f
reedesktop.org%2F~agd5f%2Flinux%2Flog%2F%3Fh%3Dbacklight_wip& data=
04%7C01%7Calexander.deucher%40amd.com%7Ce5579cfe56f74b572f1508d8 ca9ad0
ac%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637482113562863 043%7CU
nknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI 6Ik1ha
WwiLCJXVCI6Mn0%3D%7C1000&sdata=aoMSY0nvHjrLocUPJtdgckqIH7x LUPbwpH0
ZjhuuJO8%3D&reserved=0
I'm fine to scratch mine as long as the issue gets fixed :)
FWIW, the biggest problem so far was the aux channel backlight didn't work as expected, the actual backlight isn't changed by the backlight sysfs write. (And the sysfs read gives a bogus value, but it's not the cause of the non- working backlight control.)
Does the aux channel backlight really work with the current code? Or is this rather a device-specific issue (e.g. broken BIOS) and we might need to come up with a deny list or such?
@Kazlauskas, Nicholas, @Siqueira, Rodrigo
Has there been any progress on the backlight fixes?
Alex