drm/radeon/audio: make sure connector is valid in hotplug case

Avoids a crash when a monitor is hotplugged and the encoder
and connector are not linked yet.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=90681

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/gpu/drm/radeon/evergreen_hdmi.c b/drivers/gpu/drm/radeon/evergreen_hdmi.c
index 0926739c9fa7..9953356fe263 100644
--- a/drivers/gpu/drm/radeon/evergreen_hdmi.c
+++ b/drivers/gpu/drm/radeon/evergreen_hdmi.c
@@ -400,7 +400,7 @@ void evergreen_hdmi_enable(struct drm_encoder *encoder, bool enable)
         if (enable) {
                 struct drm_connector *connector = radeon_get_connector_for_encoder(encoder);
 
-                if (drm_detect_monitor_audio(radeon_connector_edid(connector))) {
+                if (connector && drm_detect_monitor_audio(radeon_connector_edid(connector))) {
                         WREG32(HDMI_INFOFRAME_CONTROL0 + dig->afmt->offset,
                                HDMI_AVI_INFO_SEND | /* enable AVI info frames */
                                HDMI_AVI_INFO_CONT | /* required for audio info values to be updated */
@@ -438,7 +438,8 @@ void evergreen_dp_enable(struct drm_encoder *encoder, bool enable)
         if (!dig || !dig->afmt)
                 return;
 
-        if (enable && drm_detect_monitor_audio(radeon_connector_edid(connector))) {
+        if (enable && connector &&
+            drm_detect_monitor_audio(radeon_connector_edid(connector))) {
                 struct drm_connector *connector = radeon_get_connector_for_encoder(encoder);
                 struct radeon_connector *radeon_connector = to_radeon_connector(connector);
                 struct radeon_connector_atom_dig *dig_connector;