4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Kai-Heng Feng kai.heng.feng@canonical.com
commit 06998a756a3865817b87a129a7e5d5bb66dc1ec3 upstream.
Similar to commit e10aec652f31 ("drm/edid: Add 6 bpc quirk for display AEO model 0."), the EDID reports "DFP 1.x compliant TMDS" but it support 6bpc instead of 8 bpc.
Hence, use 6 bpc quirk for this panel.
Fixes: 196f954e2509 ("drm/i915/dp: Revert "drm/i915/dp: fall back to 18 bpp when sink capability is unknown"") BugLink: https://bugs.launchpad.net/bugs/1749420 Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com Reviewed-by: Mario Kleiner mario.kleiner.de@gmail.com Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch Link: https://patchwork.freedesktop.org/patch/msgid/20180218085359.7817-1-kai.heng... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/drm_edid.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -106,6 +106,9 @@ static struct edid_quirk { /* AEO model 0 reports 8 bpc, but is a 6 bpc panel */ { "AEO", 0, EDID_QUIRK_FORCE_6BPC },
+ /* CPT panel of Asus UX303LA reports 8 bpc, but is a 6 bpc panel */ + { "CPT", 0x17df, EDID_QUIRK_FORCE_6BPC }, + /* Belinea 10 15 55 */ { "MAX", 1516, EDID_QUIRK_PREFER_LARGE_60 }, { "MAX", 0x77e, EDID_QUIRK_PREFER_LARGE_60 },