drm/omap: Don't store display pointer in omap_connector structure

Display pipelines based on drm_bridge are handled from the bridge
closest to the CRTC. To move to that model we thus need to transition
away from walking pipelines in the other direction, and from accessing
the device at the end of the pipeline when possible.

Remove most accesses to the display device from the omap_connector
implementation, and don't store it in the omap_connector structure.

- For debug messages we can simply use the connector name instead.
- For type checks we can use the drm_connector type.
- For operation lookup we can start at the other end of the pipeline and
  locate the last matching device.

The display device is still passed to the connector init function in
order to find its type, which requires access to the end of the
pipeline.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/omap_connector.c

@@ -30,7 +30,6 @@
 struct omap_connector {
 	struct drm_connector base;
 	struct omap_dss_device *output;
-	struct omap_dss_device *display;
 	struct omap_dss_device *hpd;
 	bool hdmi_mode;
 };
@@ -103,20 +102,20 @@ omap_connector_find_device(struct drm_connector *connector,
 			   enum omap_dss_device_ops_flag op)
 {
 	struct omap_connector *omap_connector = to_omap_connector(connector);
-	struct omap_dss_device *dssdev;
+	struct omap_dss_device *dssdev = NULL;
+	struct omap_dss_device *d;
 
-	for (dssdev = omap_connector->display; dssdev; dssdev = dssdev->src) {
-		if (dssdev->ops_flags & op)
-			return dssdev;
+	for (d = omap_connector->output; d; d = d->next) {
+		if (d->ops_flags & op)
+			dssdev = d;
 	}
 
-	return NULL;
+	return dssdev;
 }
 
 static enum drm_connector_status omap_connector_detect(
 		struct drm_connector *connector, bool force)
 {
-	struct omap_connector *omap_connector = to_omap_connector(connector);
 	struct omap_dss_device *dssdev;
 	enum drm_connector_status status;
 
@@ -130,11 +129,10 @@ static enum drm_connector_status omap_connector_detect(
 
 		omap_connector_hpd_notify(connector, dssdev->src, status);
 	} else {
-		switch (omap_connector->display->type) {
-		case OMAP_DISPLAY_TYPE_DPI:
-		case OMAP_DISPLAY_TYPE_DBI:
-		case OMAP_DISPLAY_TYPE_SDI:
-		case OMAP_DISPLAY_TYPE_DSI:
+		switch (connector->connector_type) {
+		case DRM_MODE_CONNECTOR_DPI:
+		case DRM_MODE_CONNECTOR_LVDS:
+		case DRM_MODE_CONNECTOR_DSI:
 			status = connector_status_connected;
 			break;
 		default:
@@ -143,7 +141,7 @@ static enum drm_connector_status omap_connector_detect(
 		}
 	}
 
-	VERB("%s: %d (force=%d)", omap_connector->display->name, status, force);
+	VERB("%s: %d (force=%d)", connector->name, status, force);
 
 	return status;
 }
@@ -152,7 +150,7 @@ static void omap_connector_destroy(struct drm_connector *connector)
 {
 	struct omap_connector *omap_connector = to_omap_connector(connector);
 
-	DBG("%s", omap_connector->display->name);
+	DBG("%s", connector->name);
 
 	if (omap_connector->hpd) {
 		struct omap_dss_device *hpd = omap_connector->hpd;
@@ -166,7 +164,6 @@ static void omap_connector_destroy(struct drm_connector *connector)
 	drm_connector_cleanup(connector);
 
 	omapdss_device_put(omap_connector->output);
-	omapdss_device_put(omap_connector->display);
 
 	kfree(omap_connector);
 }
@@ -210,10 +207,9 @@ static int omap_connector_get_modes_edid(struct drm_connector *connector,
 
 static int omap_connector_get_modes(struct drm_connector *connector)
 {
-	struct omap_connector *omap_connector = to_omap_connector(connector);
 	struct omap_dss_device *dssdev;
 
-	DBG("%s", omap_connector->display->name);
+	DBG("%s", connector->name);
 
 	/*
 	 * If display exposes EDID, then we parse that in the normal way to
@@ -341,7 +337,6 @@ struct drm_connector *omap_connector_init(struct drm_device *dev,
 		goto fail;
 
 	omap_connector->output = omapdss_device_get(output);
-	omap_connector->display = omapdss_device_get(display);
 
 	connector = &omap_connector->base;
 	connector->interlace_allowed = 1;