drm/radeon/kms: simplify hotplug handler logic

In the hotplug handler, just use the drm dpms functions.
If the monitor is plugged in, turn it on, if it's not,
turn it off.  This also reduces power usage by turning
off the encoder and crtc when the monitor is unplugged.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/atombios_dp.c

@@ -613,18 +613,6 @@ static bool radeon_dp_get_link_status(struct radeon_connector *radeon_connector,
 	return true;
 }
 
-bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
-{
-	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
-	u8 link_status[DP_LINK_STATUS_SIZE];
-
-	if (!radeon_dp_get_link_status(radeon_connector, link_status))
-		return false;
-	if (dp_channel_eq_ok(link_status, dig_connector->dp_lane_count))
-		return false;
-	return true;
-}
-
 struct radeon_dp_link_train_info {
 	struct radeon_device *rdev;
 	struct drm_encoder *encoder;

drivers/gpu/drm/radeon/radeon_connectors.c

@@ -50,20 +50,15 @@ void radeon_connector_hotplug(struct drm_connector *connector)
 	struct radeon_device *rdev = dev->dev_private;
 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
 
-	if (radeon_connector->hpd.hpd != RADEON_HPD_NONE)
 	radeon_hpd_set_polarity(rdev, radeon_connector->hpd.hpd);
 
-	if ((connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) ||
-	    (connector->connector_type == DRM_MODE_CONNECTOR_eDP)) {
-		if ((radeon_dp_getsinktype(radeon_connector) == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
-		    (radeon_dp_getsinktype(radeon_connector) == CONNECTOR_OBJECT_ID_eDP)) {
-			if (radeon_dp_needs_link_train(radeon_connector)) {
-				if (connector->encoder)
-					radeon_dp_link_train(connector->encoder, connector);
-			}
-		}
+	/* pre-r600 did not always have the hpd pins mapped accurately to connectors */
+	if (rdev->family >= CHIP_R600) {
+		if (radeon_hpd_sense(rdev, radeon_connector->hpd.hpd))
+			drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
+		else
+			drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
 	}
-
 }
 
 static void radeon_property_change_mode(struct drm_encoder *encoder)

drivers/gpu/drm/radeon/radeon_mode.h

@@ -470,7 +470,6 @@ extern bool radeon_connector_encoder_is_hbr2(struct drm_connector *connector);
 extern bool radeon_connector_is_dp12_capable(struct drm_connector *connector);
 
 extern void radeon_connector_hotplug(struct drm_connector *connector);
-extern bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector);
 extern int radeon_dp_mode_valid_helper(struct drm_connector *connector,
 				       struct drm_display_mode *mode);
 extern void radeon_dp_set_link_config(struct drm_connector *connector,