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 <fran...@debian.org>
---
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
