Debug log the sink's MST capability, including single-stream sideband
messaging support, and the decision whether to enable MST mode or not.
Cc: Arun R Murthy <arun.r.murthy@xxxxxxxxx>
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_dp.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index e0b8ee6bde79..4dd9c50226d1 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4008,18 +4008,27 @@ static bool intel_dp_mst_detect(struct intel_dp *intel_dp)
{
struct drm_i915_private *i915 = dp_to_i915(intel_dp);
struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
- bool sink_can_mst = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd) == DP_MST_CAPABLE;
+ enum drm_dp_mst_mode sink_mst_mode;
+ const char *mst_mode_str;
+
+ sink_mst_mode = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd);
+
+ if (sink_mst_mode == DP_MST_SIDEBAND_MSG)
+ mst_mode_str = "single-stream sideband messaging";
+ else
+ mst_mode_str = str_yes_no(sink_mst_mode == DP_MST_CAPABLE);
intel_dp->is_mst = i915->display.params.enable_dp_mst &&
intel_dp_mst_source_support(intel_dp) &&
- sink_can_mst;
+ sink_mst_mode == DP_MST_CAPABLE;
drm_dbg_kms(&i915->drm,
- "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s\n",
+ "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s -> enable: %s\n",
encoder->base.base.id, encoder->base.name,
str_yes_no(intel_dp_mst_source_support(intel_dp)),
- str_yes_no(sink_can_mst),
- str_yes_no(i915->display.params.enable_dp_mst));
+ mst_mode_str,
+ str_yes_no(i915->display.params.enable_dp_mst),
+ str_yes_no(intel_dp->is_mst));
return intel_dp->is_mst;
}
--
2.39.2
