drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check

Now that we have DRM_BRIDGE_ATTACH_NO_CONNECTOR framework, handle the
HDCP state change in bridge atomic check as well to enable correct
functioning for HDCP in both DRM_BRIDGE_ATTACH_NO_CONNECTOR and
!DRM_BRIDGE_ATTACH_NO_CONNECTOR case.

Without this patch, when using DRM_BRIDGE_ATTACH_NO_CONNECTOR flag, HDCP
state changes would not be properly handled during atomic commits,
potentially leading to HDCP authentication failures or incorrect
protection status for content requiring HDCP encryption.

Fixes: 6a3608eae6d33 ("drm: bridge: cdns-mhdp8546: Enable HDCP")
Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patch.msgid.link/20251209120332.3559893-4-h-shenoy@ti.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index 3f5cc4e90927dc20d3b239a5936f41298bb12814..c7cd0234d16861b265df436815fe8bfd6a5df377 100644 (file)
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -2123,6 +2123,10 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
 {
        struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
        const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
+       struct drm_connector_state *old_state, *new_state;
+       struct drm_atomic_state *state = crtc_state->state;
+       struct drm_connector *conn = mhdp->connector_ptr;
+       u64 old_cp, new_cp;
 
        mutex_lock(&mhdp->link_mutex);
 
@@ -2142,6 +2146,25 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
        if (mhdp->info)
                bridge_state->input_bus_cfg.flags = *mhdp->info->input_bus_flags;
 
+       if (conn && mhdp->hdcp_supported) {
+               old_state = drm_atomic_get_old_connector_state(state, conn);
+               new_state = drm_atomic_get_new_connector_state(state, conn);
+               old_cp = old_state->content_protection;
+               new_cp = new_state->content_protection;
+
+               if (old_state->hdcp_content_type != new_state->hdcp_content_type &&
+                   new_cp != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
+                       new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
+                       crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
+                       crtc_state->mode_changed = true;
+               }
+
+               if (!new_state->crtc) {
+                       if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
+                               new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
+               }
+       }
+
        mutex_unlock(&mhdp->link_mutex);
        return 0;
 }