On Wed, Jan 25, 2012 at 08:16:25AM -0800, Keith Packard wrote: > It is never correct to use intel_crtc->bpp in intel_dp_link_required, > so instead pass an explicit bpp in to this function. This patch > only supports 18bpp and 24bpp modes, which means that 10bpc modes will > be computed incorrectly. Fixing that will require more extensive > changes, and so must be addressed separately from this bugfix. > > intel_dp_link_required is called from intel_dp_mode_valid and > intel_dp_mode_fixup. > > * intel_dp_mode_valid is called to list supported modes; in this case, > the current crtc values cannot be relevant as the modes in question > may never be selected. Thus, using intel_crtc->bpp is never right. > > * intel_dp_mode_fixup is called during mode setting, but it is run > well before ironlake_crtc_mode_set is called to set intel_crtc->bpp, > so using intel_crtc-bpp in this path can only ever get a stale > value. > > Cc: Lubos Kolouch <lubos.kolouch at gmail.com> > Cc: Adam Jackson <ajax at redhat.com> > Signed-off-by: Keith Packard <keithp at keithp.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42263 Tested-by: camalot at picnicpark.org (Dell Latitude 6510) Not the original reporter and might not exactly be this bug, but likely. -Daniel -- Daniel Vetter Mail: daniel at ffwll.ch Mobile: +41 (0)79 365 57 48
