drm: bridge: Return NULL on error from drm_bridge_get_edid()

The drm_bridge_get_edid() function is documented to return an error
pointer on error. The underlying .get_edid() operation, however, returns
NULL on error, and so do the drm_get_edid() and drm_do_get_edid()
functions upon which .get_edid() is usually implemented. Make
drm_bridge_get_edid() return NULL on error to be consistent.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200526011505.31884-6-laurent.pinchart+renesas@ideasonboard.com

diff --git a/drivers/gpu/drm/bridge/ti-tfp410.c b/drivers/gpu/drm/bridge/ti-tfp410.c
index 21d99b4..6467e6f 100644 (file)
--- a/drivers/gpu/drm/bridge/ti-tfp410.c
+++ b/drivers/gpu/drm/bridge/ti-tfp410.c
@@ -51,11 +51,15 @@ static int tfp410_get_modes(struct drm_connector *connector)
        struct edid *edid;
        int ret;
 
-       edid = drm_bridge_get_edid(dvi->next_bridge, connector);
-       if (IS_ERR_OR_NULL(edid)) {
-               if (edid != ERR_PTR(-ENOTSUPP))
+       if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
+               edid = drm_bridge_get_edid(dvi->next_bridge, connector);
+               if (!edid)
                        DRM_INFO("EDID read failed. Fallback to standard modes\n");
+       } else {
+               edid = NULL;
+       }
 
+       if (!edid) {
                /*
                 * No EDID, fallback on the XGA standard modes and prefer a mode
                 * pretty much anything can handle.

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index afdec8e..fe1e346 100644 (file)
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -1086,16 +1086,16 @@ EXPORT_SYMBOL_GPL(drm_bridge_get_modes);
  *
  * If the bridge supports output EDID retrieval, as reported by the
  * DRM_BRIDGE_OP_EDID bridge ops flag, call &drm_bridge_funcs.get_edid to
- * get the EDID and return it. Otherwise return ERR_PTR(-ENOTSUPP).
+ * get the EDID and return it. Otherwise return NULL.
  *
  * RETURNS:
- * The retrieved EDID on success, or an error pointer otherwise.
+ * The retrieved EDID on success, or NULL otherwise.
  */
 struct edid *drm_bridge_get_edid(struct drm_bridge *bridge,
                                 struct drm_connector *connector)
 {
        if (!(bridge->ops & DRM_BRIDGE_OP_EDID))
-               return ERR_PTR(-ENOTSUPP);
+               return NULL;
 
        return bridge->funcs->get_edid(bridge, connector);
 }