drm/omap: Move HPD disconnection handling to omap_connector

On HDMI outputs, CEC support requires notification of HPD signal
deassertion. The HPD signal can be handled by various omap_dss_device
instances in the pipeline, and all of them forward HPD events to the
OMAP4 internal HDMI encoder.

Knowledge of the DSS internals need to be removed from the
omap_dss_device instances in order to migrate to drm_bridge. To do so,
move HPD handling for CEC to the omap_connector.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/displays/connector-hdmi.c

@@ -137,13 +137,8 @@ static int hdmic_read_edid(struct omap_dss_device *dssdev,
 static bool hdmic_detect(struct omap_dss_device *dssdev)
 {
 	struct panel_drv_data *ddata = to_panel_data(dssdev);
-	struct omap_dss_device *src = dssdev->src;
-	bool connected;
 
-	connected = gpiod_get_value_cansleep(ddata->hpd_gpio);
-	if (!connected && src->ops->hdmi.lost_hotplug)
-		src->ops->hdmi.lost_hotplug(src);
-	return connected;
+	return gpiod_get_value_cansleep(ddata->hpd_gpio);
 }
 
 static void hdmic_register_hpd_cb(struct omap_dss_device *dssdev,

drivers/gpu/drm/omapdrm/displays/encoder-tpd12s015.c

@@ -130,13 +130,8 @@ static int tpd_read_edid(struct omap_dss_device *dssdev,
 static bool tpd_detect(struct omap_dss_device *dssdev)
 {
 	struct panel_drv_data *ddata = to_panel_data(dssdev);
-	struct omap_dss_device *src = dssdev->src;
-	bool connected;
 
-	connected = gpiod_get_value_cansleep(ddata->hpd_gpio);
-	if (!connected && src->ops->hdmi.lost_hotplug)
-		src->ops->hdmi.lost_hotplug(src);
-	return connected;
+	return gpiod_get_value_cansleep(ddata->hpd_gpio);
 }
 
 static void tpd_register_hpd_cb(struct omap_dss_device *dssdev,

drivers/gpu/drm/omapdrm/omap_connector.c

@@ -34,6 +34,22 @@ struct omap_connector {
 	bool hdmi_mode;
 };
 
+static void omap_connector_hpd_notify(struct drm_connector *connector,
+				      struct omap_dss_device *src,
+				      enum drm_connector_status status)
+{
+	if (status == connector_status_disconnected) {
+		/*
+		 * If the source is an HDMI encoder, notify it of disconnection.
+		 * This is required to let the HDMI encoder reset any internal
+		 * state related to connection status, such as the CEC address.
+		 */
+		if (src && src->type == OMAP_DISPLAY_TYPE_HDMI &&
+		    src->ops->hdmi.lost_hotplug)
+			src->ops->hdmi.lost_hotplug(src);
+	}
+}
+
 static void omap_connector_hpd_cb(void *cb_data,
 				  enum drm_connector_status status)
 {
@@ -47,8 +63,12 @@ static void omap_connector_hpd_cb(void *cb_data,
 	connector->status = status;
 	mutex_unlock(&dev->mode_config.mutex);
 
-	if (old_status != status)
-		drm_kms_helper_hotplug_event(dev);
+	if (old_status == status)
+		return;
+
+	omap_connector_hpd_notify(connector, omap_connector->hpd, status);
+
+	drm_kms_helper_hotplug_event(dev);
 }
 
 void omap_connector_enable_hpd(struct drm_connector *connector)
@@ -103,10 +123,11 @@ static enum drm_connector_status omap_connector_detect(
 					    OMAP_DSS_DEVICE_OP_DETECT);
 
 	if (dssdev) {
-		if (dssdev->ops->detect(dssdev))
-			status = connector_status_connected;
-		else
-			status = connector_status_disconnected;
+		status = dssdev->ops->detect(dssdev)
+		       ? connector_status_connected
+		       : connector_status_disconnected;
+
+		omap_connector_hpd_notify(connector, dssdev->src, status);
 	} else {
 		switch (omap_connector->dssdev->type) {
 		case OMAP_DISPLAY_TYPE_DPI: