drm/bridge: Fix lvds-encoder since the panel_bridge rework.

The panel_bridge bridge attaches to the panel's OF node, not the
lvds-encoder's node.  Put in a little no-op bridge of our own so that
our consumers can still find a bridge where they expect.

This also fixes an unintended unregistration and leak of the
panel-bridge on module remove.

Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 13dfc0540a57 ("drm/bridge: Refactor out the panel wrapper from the lvds-encoder bri
dge.")
Tested-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114191647.22207-1-eric@anholt.net

diff --git a/drivers/gpu/drm/bridge/lvds-encoder.c b/drivers/gpu/drm/bridge/lvds-encoder.c
index 0903ba574f61c4d1ab40a0e18d77d852bd282c0a..75b0d3f6e4de919301b63af95b28d2b7af4bf79e 100644 (file)
--- a/drivers/gpu/drm/bridge/lvds-encoder.c
+++ b/drivers/gpu/drm/bridge/lvds-encoder.c
@@ -13,13 +13,37 @@
 
 #include <linux/of_graph.h>
 
+struct lvds_encoder {
+       struct drm_bridge bridge;
+       struct drm_bridge *panel_bridge;
+};
+
+static int lvds_encoder_attach(struct drm_bridge *bridge)
+{
+       struct lvds_encoder *lvds_encoder = container_of(bridge,
+                                                        struct lvds_encoder,
+                                                        bridge);
+
+       return drm_bridge_attach(bridge->encoder, lvds_encoder->panel_bridge,
+                                bridge);
+}
+
+static struct drm_bridge_funcs funcs = {
+       .attach = lvds_encoder_attach,
+};
+
 static int lvds_encoder_probe(struct platform_device *pdev)
 {
        struct device_node *port;
        struct device_node *endpoint;
        struct device_node *panel_node;
        struct drm_panel *panel;
-       struct drm_bridge *bridge;
+       struct lvds_encoder *lvds_encoder;
+
+       lvds_encoder = devm_kzalloc(&pdev->dev, sizeof(*lvds_encoder),
+                                   GFP_KERNEL);
+       if (!lvds_encoder)
+               return -ENOMEM;
 
        /* Locate the panel DT node. */
        port = of_graph_get_port_by_id(pdev->dev.of_node, 1);
@@ -49,20 +73,30 @@ static int lvds_encoder_probe(struct platform_device *pdev)
                return -EPROBE_DEFER;
        }
 
-       bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_LVDS);
-       if (IS_ERR(bridge))
-               return PTR_ERR(bridge);
+       lvds_encoder->panel_bridge =
+               devm_drm_panel_bridge_add(&pdev->dev,
+                                         panel, DRM_MODE_CONNECTOR_LVDS);
+       if (IS_ERR(lvds_encoder->panel_bridge))
+               return PTR_ERR(lvds_encoder->panel_bridge);
+
+       /* The panel_bridge bridge is attached to the panel's of_node,
+        * but we need a bridge attached to our of_node for our user
+        * to look up.
+        */
+       lvds_encoder->bridge.of_node = pdev->dev.of_node;
+       lvds_encoder->bridge.funcs = &funcs;
+       drm_bridge_add(&lvds_encoder->bridge);
 
-       platform_set_drvdata(pdev, bridge);
+       platform_set_drvdata(pdev, lvds_encoder);
 
        return 0;
 }
 
 static int lvds_encoder_remove(struct platform_device *pdev)
 {
-       struct drm_bridge *bridge = platform_get_drvdata(pdev);
+       struct lvds_encoder *lvds_encoder = platform_get_drvdata(pdev);
 
-       drm_bridge_remove(bridge);
+       drm_bridge_remove(&lvds_encoder->bridge);
 
        return 0;
 }