drm/i915/dp: Fix connector DSC HW state readout

The DSC HW state of DP connectors is read out during driver loading and
system resume in intel_modeset_update_connector_atomic_state(). This
function is called for all connectors though and so the state of DSI
connectors will also get updated incorrectly, triggering a WARN there
wrt. the DSC decompression AUX device.

Fix the above by moving the DSC state readout to a new DP connector
specific sync_state() hook. This is anyway the logical place to update
the connector object's state vs. the connector's atomic state.

Fixes: b2608c6b3212 ("drm/i915/dp_mst: Enable MST DSC decompression for all streams")
Reported-and-tested-by: Drew Davenport <[email protected]>
Closes: https://lore.kernel.org/all/[email protected]
Reviewed-by: Ankit Nautiyal <[email protected]>
Signed-off-by: Imre Deak <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit a62e145981500996ea76af3d740ce0c0d74c5be0)
Signed-off-by: Joonas Lahtinen <[email protected]>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index ae647d03af25..38efc8d177d0 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5859,6 +5859,19 @@ intel_dp_connector_unregister(struct drm_connector *connector)
 	intel_connector_unregister(connector);
 }
 
+void intel_dp_connector_sync_state(struct intel_connector *connector,
+				   const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *i915 = to_i915(connector->base.dev);
+
+	if (crtc_state && crtc_state->dsc.compression_enable) {
+		drm_WARN_ON(&i915->drm, !connector->dp.dsc_decompression_aux);
+		connector->dp.dsc_decompression_enabled = true;
+	} else {
+		connector->dp.dsc_decompression_enabled = false;
+	}
+}
+
 void intel_dp_encoder_flush_work(struct drm_encoder *encoder)
 {
 	struct intel_digital_port *dig_port = enc_to_dig_port(to_intel_encoder(encoder));