When crtc state need_modeset is true it is not necessary it is going to be a real modeset, it can turns to be a fastset instead of modeset. This turns content protection property to be DESIRED and hdcp update_pipe left with property to be in DESIRED state but actual hdcp->value was ENABLED.
This issue is caught with DP MST setup, where we have multiple connector in same DP_MST topology. When disabling HDCP on one of DP MST connector leads to set the crtc state need_modeset to true for all other crtc driving the other DP-MST topology connectors. This turns up other DP MST connectors CP property to be DESIRED despite the actual hdcp->value is ENABLED. Above scenario fails the DP MST HDCP IGT test, disabling HDCP on one MST stream should not cause to disable HDCP on another MST stream on same DP MST topology.
v2: Fix WARN_ON(connector->base.registration_state == DRM_CONNECTOR_REGISTERED) v3: Commit log improvement. [Uma] Added a comment before scheduling prop_work. [Uma]
Fixes: 33f9a623bfc6 ("drm/i915/hdcp: Update CP as per the kernel internal state") Cc: Ramalingam C ramalingam.c@intel.com Reviewed-by: Uma Shankar uma.shankar@intel.com Reviewed-by: Ramalingam C ramalingam.c@intel.com Signed-off-by: Anshuman Gupta anshuman.gupta@intel.com --- drivers/gpu/drm/i915/display/intel_hdcp.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c index b2a4bbcfdcd2..eee8263405b9 100644 --- a/drivers/gpu/drm/i915/display/intel_hdcp.c +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c @@ -2221,6 +2221,14 @@ void intel_hdcp_update_pipe(struct intel_atomic_state *state, desired_and_not_enabled = hdcp->value != DRM_MODE_CONTENT_PROTECTION_ENABLED; mutex_unlock(&hdcp->mutex); + /* + * If HDCP already ENABLED and CP property is DESIRED, schedule + * prop_work to update correct CP property to user space. + */ + if (!desired_and_not_enabled && !content_protection_type_changed) { + drm_connector_get(&connector->base); + schedule_work(&hdcp->prop_work); + } }
if (desired_and_not_enabled || content_protection_type_changed)