[media] em28xx: start moving em28xx-v4l specific data to its own struct

That reduces a little bit the memory footprint when em28xx-video
is not loaded.
Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/usb/em28xx/em28xx-camera.c

@@ -365,7 +365,7 @@ int em28xx_init_camera(struct em28xx *dev)
 		dev->sensor_xtal = 4300000;
 		pdata.xtal = dev->sensor_xtal;
 		if (NULL ==
-		    v4l2_i2c_new_subdev_board(&dev->v4l2_dev, adap,
+		    v4l2_i2c_new_subdev_board(&dev->v4l2->v4l2_dev, adap,
 					      &mt9v011_info, NULL)) {
 			ret = -ENODEV;
 			break;
@@ -422,7 +422,7 @@ int em28xx_init_camera(struct em28xx *dev)
 		dev->sensor_yres = 480;
 
 		subdev =
-		     v4l2_i2c_new_subdev_board(&dev->v4l2_dev, adap,
+		     v4l2_i2c_new_subdev_board(&dev->v4l2->v4l2_dev, adap,
 					       &ov2640_info, NULL);
 		if (NULL == subdev) {
 			ret = -ENODEV;

drivers/media/usb/em28xx/em28xx.h

@@ -498,6 +498,12 @@ struct em28xx_eeprom {
 #define EM28XX_RESOURCE_VIDEO 0x01
 #define EM28XX_RESOURCE_VBI   0x02
 
+struct em28xx_v4l2 {
+	struct kref ref;
+
+	struct v4l2_device v4l2_dev;
+};
+
 struct em28xx_audio {
 	char name[50];
 	unsigned num_urb;
@@ -543,6 +549,7 @@ struct em28xx {
 	struct kref ref;
 
 	/* Sub-module data */
+	struct em28xx_v4l2 *v4l2;
 	struct em28xx_dvb *dvb;
 	struct em28xx_audio adev;
 	struct em28xx_IR *ir;
@@ -560,7 +567,6 @@ struct em28xx {
 	unsigned int has_alsa_audio:1;
 	unsigned int is_audio_only:1;
 
-	struct v4l2_device v4l2_dev;
 	struct v4l2_ctrl_handler ctrl_handler;
 	struct v4l2_clk *clk;
 	struct em28xx_board board;