media: i2c: imx274: implement enum_mbus_code

Current driver supports only SRGGB 10 bit RAW bayer format.
Add the enum_mbus_code implementation to report this format supported.

 # v4l2-ctl -d /dev/v4l-subdev3 --list-subdev-mbus-codes
ioctl: VIDIOC_SUBDEV_ENUM_MBUS_CODE (pad=0)
        0x300f: MEDIA_BUS_FMT_SRGGB10_1X10
 #
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/i2c/imx274.c

@@ -1909,7 +1909,21 @@ static int imx274_set_frame_interval(struct stimx274 *priv,
 	return err;
 }
 
+static int imx274_enum_mbus_code(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_state *sd_state,
+				 struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index > 0)
+		return -EINVAL;
+
+	/* only supported format in the driver is Raw 10 bits SRGGB */
+	code->code = MEDIA_BUS_FMT_SRGGB10_1X10;
+
+	return 0;
+}
+
 static const struct v4l2_subdev_pad_ops imx274_pad_ops = {
+	.enum_mbus_code = imx274_enum_mbus_code,
 	.get_fmt = imx274_get_fmt,
 	.set_fmt = imx274_set_fmt,
 	.get_selection = imx274_get_selection,