drm/i915: Fix ivb cpu edp vswing
authorVille Syrjälä <ville.syrjala@linux.intel.com>
Tue, 12 May 2020 17:41:41 +0000 (20:41 +0300)
committerVille Syrjälä <ville.syrjala@linux.intel.com>
Wed, 3 Jun 2020 13:23:21 +0000 (16:23 +0300)
commit33520eae45f1c97670c8de7adec1cb5ab6a94416
tree7331dd35c1a1378b5d7650c1e730bdc7e72a1b0b
parentda882e6bb968b04195c32072376c4206f64037ef
drm/i915: Fix ivb cpu edp vswing

According to the DP spec supporting vswing 1 + preemph 2 is
mandatory. We don't have the hw settings for that though. In
order to pretend to follow the DP spec let's just select
vswing 0 + preemph 2 in this case (the DP spec says to use
the requested preemph in preference to the vswing when the
requested values aren't supported).

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200512174145.3186-4-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
drivers/gpu/drm/i915/display/intel_dp.c