drm/i915: do not default to 18 bpp for eDP if missing from VBT
commit 500a8cc466a24e2fbc4c86ef9c6467ae2ffdeb0c
Author: Zhenyu Wang <zhenyuw@linux.intel.com>
Date: Wed Jan 13 11:19:52 2010 +0800
drm/i915: parse eDP panel color depth from VBT block
originally introduced parsing bpp for eDP from VBT, with a default of 18
bpp if the eDP BIOS data block is not present. Turns out that default seems
to break the Macbook Pro with retina display, as noted in
commit 4344b813f105a19f793f1fd93ad775b784648b95
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Fri Aug 10 11:10:20 2012 +0200
drm/i915: ignore eDP bpc settings from vbt
Since we can't ignore bpc settings from VBT completely after all, get rid
of the default. Do not clamp eDP to 18 bpp by default if the eDP BDB is
missing from VBT.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
[danvet: paste in the updated commit message from irc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 4154bcd..b426d44 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3845,7 +3845,7 @@
/* Use VBT settings if we have an eDP panel */
unsigned int edp_bpc = dev_priv->edp.bpp / 3;
- if (edp_bpc < display_bpc) {
+ if (edp_bpc && edp_bpc < display_bpc) {
DRM_DEBUG_KMS("clamping display bpc (was %d) to eDP (%d)\n", display_bpc, edp_bpc);
display_bpc = edp_bpc;
}