[PATCH 3/5] drm/i915/dp: Pass DPCD device descriptor to intel_dp_get_dsc_sink_cap()

[Imre Deak <imre.deak@intel.com>]

Pass the DPCD sink/branch device descriptor along with the
is_branch/sink flag to intel_dp_get_dsc_sink_cap(). These will be used
by a follow up change to read out the branch device's DSC overall
throughput/line width capabilities and to detect a throughput/link-bpp
quirk.

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c     | 5 ++++-
 drivers/gpu/drm/i915/display/intel_dp.h     | 5 ++++-
 drivers/gpu/drm/i915/display/intel_dp_mst.c | 9 ++++++++-
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index a963a58c87372..8cc123b0fd752 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4204,7 +4204,9 @@ static void intel_dp_read_dsc_dpcd(struct drm_dp_aux *aux,
 		    dsc_dpcd);
 }
 
-void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, struct intel_connector *connector)
+void intel_dp_get_dsc_sink_cap(u8 dpcd_rev,
+			       const struct drm_dp_desc *desc, bool is_branch,
+			       struct intel_connector *connector)
 {
 	struct intel_display *display = to_intel_display(connector);
 
@@ -4255,6 +4257,7 @@ intel_dp_detect_dsc_caps(struct intel_dp *intel_dp, struct intel_connector *conn
 					   connector);
 	else
 		intel_dp_get_dsc_sink_cap(intel_dp->dpcd[DP_DPCD_REV],
+					  &intel_dp->desc, drm_dp_is_branch(intel_dp->dpcd),
 					  connector);
 }
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index f90cfd1dbbd05..b379443e0211e 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -12,6 +12,7 @@ enum intel_output_format;
 enum pipe;
 enum port;
 struct drm_connector_state;
+struct drm_dp_desc;
 struct drm_dp_vsc_sdp;
 struct drm_encoder;
 struct drm_modeset_acquire_ctx;
@@ -199,7 +200,9 @@ bool intel_dp_compute_config_limits(struct intel_dp *intel_dp,
 				    bool dsc,
 				    struct link_config_limits *limits);
 
-void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, struct intel_connector *connector);
+void intel_dp_get_dsc_sink_cap(u8 dpcd_rev,
+			       const struct drm_dp_desc *desc, bool is_branch,
+			       struct intel_connector *connector);
 bool intel_dp_has_gamut_metadata_dip(struct intel_encoder *encoder);
 
 bool intel_dp_link_params_valid(struct intel_dp *intel_dp, int link_rate,
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 352f7ef29c281..f2266b2653046 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -1658,6 +1658,7 @@ intel_dp_mst_read_decompression_port_dsc_caps(struct intel_dp *intel_dp,
 					      struct intel_connector *connector)
 {
 	u8 dpcd_caps[DP_RECEIVER_CAP_SIZE];
+	struct drm_dp_desc desc;
 
 	if (!connector->dp.dsc_decompression_aux)
 		return;
@@ -1665,7 +1666,13 @@ intel_dp_mst_read_decompression_port_dsc_caps(struct intel_dp *intel_dp,
 	if (drm_dp_read_dpcd_caps(connector->dp.dsc_decompression_aux, dpcd_caps) < 0)
 		return;
 
-	intel_dp_get_dsc_sink_cap(dpcd_caps[DP_DPCD_REV], connector);
+	if (drm_dp_read_desc(connector->dp.dsc_decompression_aux, &desc,
+			     drm_dp_is_branch(dpcd_caps)) < 0)
+		return;
+
+	intel_dp_get_dsc_sink_cap(dpcd_caps[DP_DPCD_REV],
+				  &desc, drm_dp_is_branch(dpcd_caps),
+				  connector);
 }
 
 static bool detect_dsc_hblank_expansion_quirk(const struct intel_connector *connector)
-- 
2.49.1