Check only the eDP or the DP specific DPCD revision depending on the sink type. Pass the corresponding revision to the function, which allows getting the DSC caps of a branch device (in an MST topology, which has its own DPCD and so DPCD revision). Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_dp.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 0ef7cb8134b66..1bd11f9e308c1 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -3467,7 +3467,7 @@ bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp) return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED; } -static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp) +static void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, struct intel_dp *intel_dp) { struct drm_i915_private *i915 = dp_to_i915(intel_dp); @@ -3481,8 +3481,8 @@ static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp) intel_dp->fec_capable = 0; /* Cache the DSC DPCD if eDP or DP rev >= 1.4 */ - if (intel_dp->dpcd[DP_DPCD_REV] >= 0x14 || - intel_dp->edp_dpcd[0] >= DP_EDP_14) { + if ((intel_dp_is_edp(intel_dp) && dpcd_rev >= DP_EDP_14) || + (!intel_dp_is_edp(intel_dp) && dpcd_rev >= 0x14)) { if (drm_dp_dpcd_read(&intel_dp->aux, DP_DSC_SUPPORT, intel_dp->dsc_dpcd, sizeof(intel_dp->dsc_dpcd)) < 0) @@ -3674,7 +3674,8 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp) /* Read the eDP DSC DPCD registers */ if (HAS_DSC(dev_priv)) - intel_dp_get_dsc_sink_cap(intel_dp); + intel_dp_get_dsc_sink_cap(intel_dp->edp_dpcd[0], + intel_dp); /* * If needed, program our source OUI so we can make various Intel-specific AUX services @@ -5384,7 +5385,8 @@ intel_dp_detect(struct drm_connector *connector, /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */ if (HAS_DSC(dev_priv)) - intel_dp_get_dsc_sink_cap(intel_dp); + intel_dp_get_dsc_sink_cap(intel_dp->dpcd[DP_DPCD_REV], + intel_dp); intel_dp_configure_mst(intel_dp); -- 2.39.2