[RFC PATCH v1 04/12] drm/bridge-connector: set the PATH property for the connector

[Dmitry Baryshkov]

In order to properly identify connectors (in particular, DisplayPort
connectors wrapped into USB-C) allow bridge drivers to specify the value
to be used for connector's PATH property.

Signed-off-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org>
---
 drivers/gpu/drm/drm_bridge_connector.c | 12 ++++++++++++
 include/drm/drm_bridge.h               |  7 +++++++
 2 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/drm_bridge_connector.c 
b/drivers/gpu/drm/drm_bridge_connector.c
index bf73960c2c2a..008d730e1c2f 100644
--- a/drivers/gpu/drm/drm_bridge_connector.c
+++ b/drivers/gpu/drm/drm_bridge_connector.c
@@ -331,6 +331,7 @@ struct drm_connector *drm_bridge_connector_init(struct 
drm_device *drm,
        struct drm_connector *connector;
        struct i2c_adapter *ddc = NULL;
        struct drm_bridge *bridge, *panel_bridge = NULL;
+       const char *path = NULL;
        int connector_type;
        int ret;
 
@@ -377,6 +378,9 @@ struct drm_connector *drm_bridge_connector_init(struct 
drm_device *drm,
                        connector->fwnode = 
fwnode_handle_get(of_fwnode_handle(bridge->of_node));
 #endif
 
+               if (bridge->path)
+                       path = bridge->path;
+
                if (bridge->ddc)
                        ddc = bridge->ddc;
 
@@ -405,6 +409,14 @@ struct drm_connector *drm_bridge_connector_init(struct 
drm_device *drm,
                connector->polled = DRM_CONNECTOR_POLL_CONNECT
                                  | DRM_CONNECTOR_POLL_DISCONNECT;
 
+       if (path) {
+               drm_object_attach_property(&connector->base,
+                                          drm->mode_config.path_property,
+                                          0);
+
+               drm_connector_set_path_property(connector, path);
+       }
+
        if (panel_bridge)
                drm_panel_bridge_set_orientation(connector, panel_bridge);
 
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index c339fc85fd07..98e9d76474f4 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -753,6 +753,13 @@ struct drm_bridge {
         * before the peripheral.
         */
        bool pre_enable_prev_first;
+       /**
+        * @path: the 'path' of the bridge. For bridges at the end of this
+        * chain this is used to set the 'PATH' property of the connector.
+        * This string is not freed manually, so one either should use a static
+        * string here or a devres-allocated one.
+        */
+       const char *path;
        /**
         * @ddc: Associated I2C adapter for DDC access, if any.
         */
-- 
2.39.2