Hi, there is an issue with Lenovo Thinkpad L540 very similar to those described here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1749420 or here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1788308 that is a bad looking color banding with dark colors mainly. It happens with any kernel starting from 4.8 up to the current. Signed-off-by: Francesco Paolo Lovergine <frankie@xxxxxxxxxx> --- drivers/gpu/drm/drm_edid.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 6325877c5fd6..48e06cc33e4d 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -141,6 +141,9 @@ static const struct edid_quirk { /* LGD panel of HP zBook 17 G2, eDP 10 bpc, but reports unknown bpc */ { "LGD", 764, EDID_QUIRK_FORCE_10BPC }, + /* LGD panel of Lenovo L540 reports 8 bpc, but is a 6 bpc panel */ + { "LGD", 0x038e, EDID_QUIRK_FORCE_6BPC }, + /* LG Philips LCD LP154W01-A5 */ { "LPL", 0, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE }, { "LPL", 0x2a00, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE }, -- 2.30.2 -- Francesco P. Lovergine
