drm/radeon: fix hotplug of DP to DVI|HDMI passive adapters (v2)

No need to retrain the link for passive adapters.

v2: agd5f
- no passive DP to VGA adapters, update comments
- assign radeon_connector_atom_dig after we are sure
  we have a digital connector as analog connectors
  have different private data.
- get new sink type before checking for retrain.  No
  need to check if it's no longer a DP connection.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 21 insertions, 8 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 2914c5761cfc..3524f17e3f05 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -64,14 +64,27 @@ void radeon_connector_hotplug(struct drm_connector *connector)
 
         /* just deal with DP (not eDP) here. */
         if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
-                int saved_dpms = connector->dpms;
-
-                /* Only turn off the display it it's physically disconnected */
-                if (!radeon_hpd_sense(rdev, radeon_connector->hpd.hpd))
-                        drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
-                else if (radeon_dp_needs_link_train(radeon_connector))
-                        drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
-                connector->dpms = saved_dpms;
+                struct radeon_connector_atom_dig *dig_connector =
+                        radeon_connector->con_priv;
+
+                /* if existing sink type was not DP no need to retrain */
+                if (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT)
+                        return;
+
+                /* first get sink type as it may be reset after (un)plug */
+                dig_connector->dp_sink_type = radeon_dp_getsinktype(radeon_connector);
+                /* don't do anything if sink is not display port, i.e.,
+                 * passive dp->(dvi|hdmi) adaptor
+                 */
+                if (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) {
+                        int saved_dpms = connector->dpms;
+                        /* Only turn off the display if it's physically disconnected */
+                        if (!radeon_hpd_sense(rdev, radeon_connector->hpd.hpd))
+                                drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
+                        else if (radeon_dp_needs_link_train(radeon_connector))
+                                drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
+                        connector->dpms = saved_dpms;
+                }
         }
 }