dm: video: bridge: add operation to read EDID

Add an operation to read EDID, since bridge may have ability to read
EDID from the panel that is connected to it, for example LCD<->eDP bridge.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>

drivers/video/bridge/video-bridge-uclass.c

@@ -8,6 +8,7 @@
 #include <common.h>
 #include <dm.h>
 #include <errno.h>
+#include <edid.h>
 #include <video_bridge.h>
 
 int video_bridge_set_backlight(struct udevice *dev, int percent)
@@ -45,6 +46,15 @@ int video_bridge_check_attached(struct udevice *dev)
 	return ops->check_attached(dev);
 }
 
+int video_bridge_read_edid(struct udevice *dev, u8 *buf, int buf_size)
+{
+	struct video_bridge_ops *ops = video_bridge_get_ops(dev);
+
+	if (!ops || !ops->read_edid)
+		return -ENOSYS;
+	return ops->read_edid(dev, buf, buf_size);
+}
+
 static int video_bridge_pre_probe(struct udevice *dev)
 {
 	struct video_bridge_priv *uc_priv = dev_get_uclass_priv(dev);

include/video_bridge.h

@@ -53,6 +53,16 @@ struct video_bridge_ops {
 	 * @return 0 if OK, -ve on error
 	 */
 	int (*set_backlight)(struct udevice *dev, int percent);
+
+	/**
+	 * read_edid() - Read information from EDID
+	 *
+	 * @dev:	Device to read from
+	 * @buf:	Buffer to read into
+	 * @buf_size:	Buffer size
+	 * @return number of bytes read, <=0 for error
+	 */
+	int (*read_edid)(struct udevice *dev, u8 *buf, int buf_size);
 };
 
 #define video_bridge_get_ops(dev) \
@@ -89,4 +99,14 @@ int video_bridge_set_active(struct udevice *dev, bool active);
  */
 int video_bridge_check_attached(struct udevice *dev);
 
+/**
+ * video_bridge_read_edid() - Read information from EDID
+ *
+ * @dev:	Device to read from
+ * @buf:	Buffer to read into
+ * @buf_size:	Buffer size
+ * @return number of bytes read, <=0 for error
+ */
+int video_bridge_read_edid(struct udevice *dev, u8 *buf, int buf_size);
+
 #endif