text: /*
     em28xx-video.c - driver for Empia EM2800/EM2820/2840 USB
  		    video capture devices
  
     Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
  		      Markus Rechberger <mrechberger@gmail.com>
  		      Mauro Carvalho Chehab <mchehab@infradead.org>
  		      Sascha Sommer <saschasommer@freenet.de>
     Copyright (C) 2012 Frank Schäfer <fschaefer.oss@googlemail.com>
  
  	Some parts based on SN9C10x PC Camera Controllers GPL driver made
  		by Luca Risolia <luca.risolia@studio.unibo.it>
  
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.
  
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
  
     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  #include <linux/init.h>
  #include <linux/list.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/bitmap.h>
  #include <linux/usb.h>
  #include <linux/i2c.h>
  #include <linux/mm.h>
  #include <linux/mutex.h>
  #include <linux/slab.h>
  
  #include "em28xx.h"
  #include "em28xx-v4l.h"
  #include <media/v4l2-common.h>
  #include <media/v4l2-ioctl.h>
  #include <media/v4l2-event.h>
  #include <media/v4l2-clk.h>
  #include <media/drv-intf/msp3400.h>
  #include <media/tuner.h>
  
  #define DRIVER_AUTHOR "Ludovico Cavedon <cavedon@sssup.it>, " \
  		      "Markus Rechberger <mrechberger@gmail.com>, " \
  		      "Mauro Carvalho Chehab <mchehab@infradead.org>, " \
  		      "Sascha Sommer <saschasommer@freenet.de>"
  
  static unsigned int isoc_debug;
  module_param(isoc_debug, int, 0644);
  MODULE_PARM_DESC(isoc_debug, "enable debug messages [isoc transfers]");
  
  static unsigned int disable_vbi;
  module_param(disable_vbi, int, 0644);
  MODULE_PARM_DESC(disable_vbi, "disable vbi support");
  
  static int alt;
  module_param(alt, int, 0644);
  MODULE_PARM_DESC(alt, "alternate setting to use for video endpoint");
  
  #define em28xx_videodbg(fmt, arg...) do {\
  	if (video_debug) \
  		printk(KERN_INFO "%s %s :"fmt, \
  			 dev->name, __func__ , ##arg); } while (0)
  
  #define em28xx_isocdbg(fmt, arg...) \
  do {\
  	if (isoc_debug) { \
  		printk(KERN_INFO "%s %s :"fmt, \
  			 dev->name, __func__ , ##arg); \
  	} \
    } while (0)
  
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC " - v4l2 interface");
  MODULE_LICENSE("GPL");
  MODULE_VERSION(EM28XX_VERSION);
  
  #define EM25XX_FRMDATAHDR_BYTE1			0x02
  #define EM25XX_FRMDATAHDR_BYTE2_STILL_IMAGE	0x20
  #define EM25XX_FRMDATAHDR_BYTE2_FRAME_END	0x02
  #define EM25XX_FRMDATAHDR_BYTE2_FRAME_ID	0x01
  #define EM25XX_FRMDATAHDR_BYTE2_MASK	(EM25XX_FRMDATAHDR_BYTE2_STILL_IMAGE | \
  					 EM25XX_FRMDATAHDR_BYTE2_FRAME_END |   \
  					 EM25XX_FRMDATAHDR_BYTE2_FRAME_ID)
  
  static unsigned int video_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U };
  static unsigned int vbi_nr[]   = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U };
  static unsigned int radio_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U };
  
  module_param_array(video_nr, int, NULL, 0444);
  module_param_array(vbi_nr, int, NULL, 0444);
  module_param_array(radio_nr, int, NULL, 0444);
  MODULE_PARM_DESC(video_nr, "video device numbers");
  MODULE_PARM_DESC(vbi_nr,   "vbi device numbers");
  MODULE_PARM_DESC(radio_nr, "radio device numbers");
  
  static unsigned int video_debug;
  module_param(video_debug, int, 0644);
  MODULE_PARM_DESC(video_debug, "enable debug messages [video]");
  
  /* supported video standards */
  static struct em28xx_fmt format[] = {
  	{
  		.name     = "16 bpp YUY2, 4:2:2, packed",
  		.fourcc   = V4L2_PIX_FMT_YUYV,
  		.depth    = 16,
  		.reg	  = EM28XX_OUTFMT_YUV422_Y0UY1V,
  	}, {
  		.name     = "16 bpp RGB 565, LE",
  		.fourcc   = V4L2_PIX_FMT_RGB565,
  		.depth    = 16,
  		.reg      = EM28XX_OUTFMT_RGB_16_656,
  	}, {
  		.name     = "8 bpp Bayer BGBG..GRGR",
  		.fourcc   = V4L2_PIX_FMT_SBGGR8,
  		.depth    = 8,
  		.reg      = EM28XX_OUTFMT_RGB_8_BGBG,
  	}, {
  		.name     = "8 bpp Bayer GRGR..BGBG",
  		.fourcc   = V4L2_PIX_FMT_SGRBG8,
  		.depth    = 8,
  		.reg      = EM28XX_OUTFMT_RGB_8_GRGR,
  	}, {
  		.name     = "8 bpp Bayer GBGB..RGRG",
  		.fourcc   = V4L2_PIX_FMT_SGBRG8,
  		.depth    = 8,
  		.reg      = EM28XX_OUTFMT_RGB_8_GBGB,
  	}, {
  		.name     = "12 bpp YUV411",
  		.fourcc   = V4L2_PIX_FMT_YUV411P,
  		.depth    = 12,
  		.reg      = EM28XX_OUTFMT_YUV411,
  	},
  };
  
  /*FIXME: maxw should be dependent of alt mode */
  static inline unsigned int norm_maxw(struct em28xx *dev)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	if (dev->board.is_webcam)
  		return v4l2->sensor_xres;
  
  	if (dev->board.max_range_640_480)
  		return 640;
  
  	return 720;
  }
  
  static inline unsigned int norm_maxh(struct em28xx *dev)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	if (dev->board.is_webcam)
  		return v4l2->sensor_yres;
  
  	if (dev->board.max_range_640_480)
  		return 480;
  
  	return (v4l2->norm & V4L2_STD_625_50) ? 576 : 480;
  }
  
  static int em28xx_vbi_supported(struct em28xx *dev)
  {
  	/* Modprobe option to manually disable */
  	if (disable_vbi == 1)
  		return 0;
  
  	if (dev->board.is_webcam)
  		return 0;
  
  	/* FIXME: check subdevices for VBI support */
  
  	if (dev->chip_id == CHIP_ID_EM2860 ||
  	    dev->chip_id == CHIP_ID_EM2883)
  		return 1;
  
  	/* Version of em28xx that does not support VBI */
  	return 0;
  }
  
  /*
   * em28xx_wake_i2c()
   * configure i2c attached devices
   */
  static void em28xx_wake_i2c(struct em28xx *dev)
  {
  	struct v4l2_device *v4l2_dev = &dev->v4l2->v4l2_dev;
  
  	v4l2_device_call_all(v4l2_dev, 0, core,  reset, 0);
  	v4l2_device_call_all(v4l2_dev, 0, video, s_routing,
  			     INPUT(dev->ctl_input)->vmux, 0, 0);
  }
  
  static int em28xx_colorlevels_set_default(struct em28xx *dev)
  {
  	em28xx_write_reg(dev, EM28XX_R20_YGAIN, CONTRAST_DEFAULT);
  	em28xx_write_reg(dev, EM28XX_R21_YOFFSET, BRIGHTNESS_DEFAULT);
  	em28xx_write_reg(dev, EM28XX_R22_UVGAIN, SATURATION_DEFAULT);
  	em28xx_write_reg(dev, EM28XX_R23_UOFFSET, BLUE_BALANCE_DEFAULT);
  	em28xx_write_reg(dev, EM28XX_R24_VOFFSET, RED_BALANCE_DEFAULT);
  	em28xx_write_reg(dev, EM28XX_R25_SHARPNESS, SHARPNESS_DEFAULT);
  
  	em28xx_write_reg(dev, EM28XX_R14_GAMMA, 0x20);
  	em28xx_write_reg(dev, EM28XX_R15_RGAIN, 0x20);
  	em28xx_write_reg(dev, EM28XX_R16_GGAIN, 0x20);
  	em28xx_write_reg(dev, EM28XX_R17_BGAIN, 0x20);
  	em28xx_write_reg(dev, EM28XX_R18_ROFFSET, 0x00);
  	em28xx_write_reg(dev, EM28XX_R19_GOFFSET, 0x00);
  	return em28xx_write_reg(dev, EM28XX_R1A_BOFFSET, 0x00);
  }
  
  static int em28xx_set_outfmt(struct em28xx *dev)
  {
  	int ret;
  	u8 fmt, vinctrl;
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	fmt = v4l2->format->reg;
  	if (!dev->is_em25xx)
  		fmt |= 0x20;
  	/*
  	 * NOTE: it's not clear if this is really needed !
  	 * The datasheets say bit 5 is a reserved bit and devices seem to work
  	 * fine without it. But the Windows driver sets it for em2710/50+em28xx
  	 * devices and we've always been setting it, too.
  	 *
  	 * em2765 (em25xx, em276x/7x/8x) devices do NOT work with this bit set,
  	 * it's likely used for an additional (compressed ?) format there.
  	 */
  	ret = em28xx_write_reg(dev, EM28XX_R27_OUTFMT, fmt);
  	if (ret < 0)
  		return ret;
  
  	ret = em28xx_write_reg(dev, EM28XX_R10_VINMODE, v4l2->vinmode);
  	if (ret < 0)
  		return ret;
  
  	vinctrl = v4l2->vinctl;
  	if (em28xx_vbi_supported(dev) == 1) {
  		vinctrl |= EM28XX_VINCTRL_VBI_RAW;
  		em28xx_write_reg(dev, EM28XX_R34_VBI_START_H, 0x00);
  		em28xx_write_reg(dev, EM28XX_R36_VBI_WIDTH, v4l2->vbi_width/4);
  		em28xx_write_reg(dev, EM28XX_R37_VBI_HEIGHT, v4l2->vbi_height);
  		if (v4l2->norm & V4L2_STD_525_60) {
  			/* NTSC */
  			em28xx_write_reg(dev, EM28XX_R35_VBI_START_V, 0x09);
  		} else if (v4l2->norm & V4L2_STD_625_50) {
  			/* PAL */
  			em28xx_write_reg(dev, EM28XX_R35_VBI_START_V, 0x07);
  		}
  	}
  
  	return em28xx_write_reg(dev, EM28XX_R11_VINCTRL, vinctrl);
  }
  
  static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
  				  u8 ymin, u8 ymax)
  {
  	em28xx_videodbg("em28xx Scale: (%d,%d)-(%d,%d)\n",
  			xmin, ymin, xmax, ymax);
  
  	em28xx_write_regs(dev, EM28XX_R28_XMIN, &xmin, 1);
  	em28xx_write_regs(dev, EM28XX_R29_XMAX, &xmax, 1);
  	em28xx_write_regs(dev, EM28XX_R2A_YMIN, &ymin, 1);
  	return em28xx_write_regs(dev, EM28XX_R2B_YMAX, &ymax, 1);
  }
  
  static void em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
  				    u16 width, u16 height)
  {
  	u8 cwidth = width >> 2;
  	u8 cheight = height >> 2;
  	u8 overflow = (height >> 9 & 0x02) | (width >> 10 & 0x01);
  	/* NOTE: size limit: 2047x1023 = 2MPix */
  
  	em28xx_videodbg("capture area set to (%d,%d): %dx%d\n",
  			hstart, vstart,
  		       ((overflow & 2) << 9 | cwidth << 2),
  		       ((overflow & 1) << 10 | cheight << 2));
  
  	em28xx_write_regs(dev, EM28XX_R1C_HSTART, &hstart, 1);
  	em28xx_write_regs(dev, EM28XX_R1D_VSTART, &vstart, 1);
  	em28xx_write_regs(dev, EM28XX_R1E_CWIDTH, &cwidth, 1);
  	em28xx_write_regs(dev, EM28XX_R1F_CHEIGHT, &cheight, 1);
  	em28xx_write_regs(dev, EM28XX_R1B_OFLOW, &overflow, 1);
  
  	/* FIXME: function/meaning of these registers ? */
  	/* FIXME: align width+height to multiples of 4 ?! */
  	if (dev->is_em25xx) {
  		em28xx_write_reg(dev, 0x34, width >> 4);
  		em28xx_write_reg(dev, 0x35, height >> 4);
  	}
  }
  
  static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
  {
  	u8 mode = 0x00;
  	/* the em2800 scaler only supports scaling down to 50% */
  
  	if (dev->board.is_em2800) {
  		mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
  	} else {
  		u8 buf[2];
  
  		buf[0] = h;
  		buf[1] = h >> 8;
  		em28xx_write_regs(dev, EM28XX_R30_HSCALELOW, (char *)buf, 2);
  
  		buf[0] = v;
  		buf[1] = v >> 8;
  		em28xx_write_regs(dev, EM28XX_R32_VSCALELOW, (char *)buf, 2);
  		/* it seems that both H and V scalers must be active
  		   to work correctly */
  		mode = (h || v) ? 0x30 : 0x00;
  	}
  	return em28xx_write_reg(dev, EM28XX_R26_COMPR, mode);
  }
  
  /* FIXME: this only function read values from dev */
  static int em28xx_resolution_set(struct em28xx *dev)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	int width = norm_maxw(dev);
  	int height = norm_maxh(dev);
  
  	/* Properly setup VBI */
  	v4l2->vbi_width = 720;
  	if (v4l2->norm & V4L2_STD_525_60)
  		v4l2->vbi_height = 12;
  	else
  		v4l2->vbi_height = 18;
  
  	em28xx_set_outfmt(dev);
  
  	em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
  
  	/* If we don't set the start position to 2 in VBI mode, we end up
  	   with line 20/21 being YUYV encoded instead of being in 8-bit
  	   greyscale.  The core of the issue is that line 21 (and line 23 for
  	   PAL WSS) are inside of active video region, and as a result they
  	   get the pixelformatting associated with that area.  So by cropping
  	   it out, we end up with the same format as the rest of the VBI
  	   region */
  	if (em28xx_vbi_supported(dev) == 1)
  		em28xx_capture_area_set(dev, 0, 2, width, height);
  	else
  		em28xx_capture_area_set(dev, 0, 0, width, height);
  
  	return em28xx_scaler_set(dev, v4l2->hscale, v4l2->vscale);
  }
  
  /* Set USB alternate setting for analog video */
  static int em28xx_set_alternate(struct em28xx *dev)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	int errCode;
  	int i;
  	unsigned int min_pkt_size = v4l2->width * 2 + 4;
  
  	/* NOTE: for isoc transfers, only alt settings > 0 are allowed
  		 bulk transfers seem to work only with alt=0 ! */
  	dev->alt = 0;
  	if ((alt > 0) && (alt < dev->num_alt)) {
  		em28xx_videodbg("alternate forced to %d\n", dev->alt);
  		dev->alt = alt;
  		goto set_alt;
  	}
  	if (dev->analog_xfer_bulk)
  		goto set_alt;
  
  	/* When image size is bigger than a certain value,
  	   the frame size should be increased, otherwise, only
  	   green screen will be received.
  	 */
  	if (v4l2->width * 2 * v4l2->height > 720 * 240 * 2)
  		min_pkt_size *= 2;
  
  	for (i = 0; i < dev->num_alt; i++) {
  		/* stop when the selected alt setting offers enough bandwidth */
  		if (dev->alt_max_pkt_size_isoc[i] >= min_pkt_size) {
  			dev->alt = i;
  			break;
  		/* otherwise make sure that we end up with the maximum bandwidth
  		   because the min_pkt_size equation might be wrong...
  		*/
  		} else if (dev->alt_max_pkt_size_isoc[i] >
  			   dev->alt_max_pkt_size_isoc[dev->alt])
  			dev->alt = i;
  	}
  
  set_alt:
  	/* NOTE: for bulk transfers, we need to call usb_set_interface()
  	 * even if the previous settings were the same. Otherwise streaming
  	 * fails with all urbs having status = -EOVERFLOW ! */
  	if (dev->analog_xfer_bulk) {
  		dev->max_pkt_size = 512; /* USB 2.0 spec */
  		dev->packet_multiplier = EM28XX_BULK_PACKET_MULTIPLIER;
  	} else { /* isoc */
  		em28xx_videodbg("minimum isoc packet size: %u (alt=%d)\n",
  				min_pkt_size, dev->alt);
  		dev->max_pkt_size =
  				  dev->alt_max_pkt_size_isoc[dev->alt];
  		dev->packet_multiplier = EM28XX_NUM_ISOC_PACKETS;
  	}
  	em28xx_videodbg("setting alternate %d with wMaxPacketSize=%u\n",
  			dev->alt, dev->max_pkt_size);
  	errCode = usb_set_interface(dev->udev, dev->ifnum, dev->alt);
  	if (errCode < 0) {
  		em28xx_errdev("cannot change alternate number to %d (error=%i)\n",
  			      dev->alt, errCode);
  		return errCode;
  	}
  	return 0;
  }
  
  /* ------------------------------------------------------------------
  	DMA and thread functions
     ------------------------------------------------------------------*/
  
  /*
   * Finish the current buffer
   */
  static inline void finish_buffer(struct em28xx *dev,
  				 struct em28xx_buffer *buf)
  {
  	em28xx_isocdbg("[%p/%d] wakeup\n", buf, buf->top_field);
  
  	buf->vb.sequence = dev->v4l2->field_count++;
  	if (dev->v4l2->progressive)
  		buf->vb.field = V4L2_FIELD_NONE;
  	else
  		buf->vb.field = V4L2_FIELD_INTERLACED;
  	buf->vb.vb2_buf.timestamp = ktime_get_ns();
  
  	vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
  }
  
  /*
   * Copy picture data from USB buffer to videobuf buffer
   */
  static void em28xx_copy_video(struct em28xx *dev,
  			      struct em28xx_buffer *buf,
  			      unsigned char *usb_buf,
  			      unsigned long len)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	void *fieldstart, *startwrite, *startread;
  	int  linesdone, currlinedone, offset, lencopy, remain;
  	int bytesperline = v4l2->width << 1;
  
  	if (buf->pos + len > buf->length)
  		len = buf->length - buf->pos;
  
  	startread = usb_buf;
  	remain = len;
  
  	if (v4l2->progressive || buf->top_field)
  		fieldstart = buf->vb_buf;
  	else /* interlaced mode, even nr. of lines */
  		fieldstart = buf->vb_buf + bytesperline;
  
  	linesdone = buf->pos / bytesperline;
  	currlinedone = buf->pos % bytesperline;
  
  	if (v4l2->progressive)
  		offset = linesdone * bytesperline + currlinedone;
  	else
  		offset = linesdone * bytesperline * 2 + currlinedone;
  
  	startwrite = fieldstart + offset;
  	lencopy = bytesperline - currlinedone;
  	lencopy = lencopy > remain ? remain : lencopy;
  
  	if ((char *)startwrite + lencopy > (char *)buf->vb_buf + buf->length) {
  		em28xx_isocdbg("Overflow of %zu bytes past buffer end (1)\n",
  			       ((char *)startwrite + lencopy) -
  			      ((char *)buf->vb_buf + buf->length));
  		remain = (char *)buf->vb_buf + buf->length -
  			 (char *)startwrite;
  		lencopy = remain;
  	}
  	if (lencopy <= 0)
  		return;
  	memcpy(startwrite, startread, lencopy);
  
  	remain -= lencopy;
  
  	while (remain > 0) {
  		if (v4l2->progressive)
  			startwrite += lencopy;
  		else
  			startwrite += lencopy + bytesperline;
  		startread += lencopy;
  		if (bytesperline > remain)
  			lencopy = remain;
  		else
  			lencopy = bytesperline;
  
  		if ((char *)startwrite + lencopy > (char *)buf->vb_buf +
  		    buf->length) {
  			em28xx_isocdbg("Overflow of %zu bytes past buffer end"
  				       "(2)\n",
  				       ((char *)startwrite + lencopy) -
  				       ((char *)buf->vb_buf + buf->length));
  			lencopy = remain = (char *)buf->vb_buf + buf->length -
  				(char *)startwrite;
  		}
  		if (lencopy <= 0)
  			break;
  
  		memcpy(startwrite, startread, lencopy);
  
  		remain -= lencopy;
  	}
  
  	buf->pos += len;
  }
  
  /*
   * Copy VBI data from USB buffer to videobuf buffer
   */
  static void em28xx_copy_vbi(struct em28xx *dev,
  			    struct em28xx_buffer *buf,
  			    unsigned char *usb_buf,
  			    unsigned long len)
  {
  	unsigned int offset;
  
  	if (buf->pos + len > buf->length)
  		len = buf->length - buf->pos;
  
  	offset = buf->pos;
  	/* Make sure the bottom field populates the second half of the frame */
  	if (buf->top_field == 0)
  		offset += dev->v4l2->vbi_width * dev->v4l2->vbi_height;
  
  	memcpy(buf->vb_buf + offset, usb_buf, len);
  	buf->pos += len;
  }
  
  static inline void print_err_status(struct em28xx *dev,
  				    int packet, int status)
  {
  	char *errmsg = "Unknown";
  
  	switch (status) {
  	case -ENOENT:
  		errmsg = "unlinked synchronuously";
  		break;
  	case -ECONNRESET:
  		errmsg = "unlinked asynchronuously";
  		break;
  	case -ENOSR:
  		errmsg = "Buffer error (overrun)";
  		break;
  	case -EPIPE:
  		errmsg = "Stalled (device not responding)";
  		break;
  	case -EOVERFLOW:
  		errmsg = "Babble (bad cable?)";
  		break;
  	case -EPROTO:
  		errmsg = "Bit-stuff error (bad cable?)";
  		break;
  	case -EILSEQ:
  		errmsg = "CRC/Timeout (could be anything)";
  		break;
  	case -ETIME:
  		errmsg = "Device does not respond";
  		break;
  	}
  	if (packet < 0) {
  		em28xx_isocdbg("URB status %d [%s].\n",	status, errmsg);
  	} else {
  		em28xx_isocdbg("URB packet %d, status %d [%s].\n",
  			       packet, status, errmsg);
  	}
  }
  
  /*
   * get the next available buffer from dma queue
   */
  static inline struct em28xx_buffer *get_next_buf(struct em28xx *dev,
  						 struct em28xx_dmaqueue *dma_q)
  {
  	struct em28xx_buffer *buf;
  
  	if (list_empty(&dma_q->active)) {
  		em28xx_isocdbg("No active queue to serve\n");
  		return NULL;
  	}
  
  	/* Get the next buffer */
  	buf = list_entry(dma_q->active.next, struct em28xx_buffer, list);
  	/* Cleans up buffer - Useful for testing for frame/URB loss */
  	list_del(&buf->list);
  	buf->pos = 0;
  	buf->vb_buf = buf->mem;
  
  	return buf;
  }
  
  /*
   * Finish the current buffer if completed and prepare for the next field
   */
  static struct em28xx_buffer *
  finish_field_prepare_next(struct em28xx *dev,
  			  struct em28xx_buffer *buf,
  			  struct em28xx_dmaqueue *dma_q)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	if (v4l2->progressive || v4l2->top_field) { /* Brand new frame */
  		if (buf != NULL)
  			finish_buffer(dev, buf);
  		buf = get_next_buf(dev, dma_q);
  	}
  	if (buf != NULL) {
  		buf->top_field = v4l2->top_field;
  		buf->pos = 0;
  	}
  
  	return buf;
  }
  
  /*
   * Process data packet according to the em2710/em2750/em28xx frame data format
   */
  static inline void process_frame_data_em28xx(struct em28xx *dev,
  					     unsigned char *data_pkt,
  					     unsigned int  data_len)
  {
  	struct em28xx_v4l2      *v4l2 = dev->v4l2;
  	struct em28xx_buffer    *buf = dev->usb_ctl.vid_buf;
  	struct em28xx_buffer    *vbi_buf = dev->usb_ctl.vbi_buf;
  	struct em28xx_dmaqueue  *dma_q = &dev->vidq;
  	struct em28xx_dmaqueue  *vbi_dma_q = &dev->vbiq;
  
  	/* capture type 0 = vbi start
  	   capture type 1 = vbi in progress
  	   capture type 2 = video start
  	   capture type 3 = video in progress */
  	if (data_len >= 4) {
  		/* NOTE: Headers are always 4 bytes and
  		 * never split across packets */
  		if (data_pkt[0] == 0x88 && data_pkt[1] == 0x88 &&
  		    data_pkt[2] == 0x88 && data_pkt[3] == 0x88) {
  			/* Continuation */
  			data_pkt += 4;
  			data_len -= 4;
  		} else if (data_pkt[0] == 0x33 && data_pkt[1] == 0x95) {
  			/* Field start (VBI mode) */
  			v4l2->capture_type = 0;
  			v4l2->vbi_read = 0;
  			em28xx_isocdbg("VBI START HEADER !!!\n");
  			v4l2->top_field = !(data_pkt[2] & 1);
  			data_pkt += 4;
  			data_len -= 4;
  		} else if (data_pkt[0] == 0x22 && data_pkt[1] == 0x5a) {
  			/* Field start (VBI disabled) */
  			v4l2->capture_type = 2;
  			em28xx_isocdbg("VIDEO START HEADER !!!\n");
  			v4l2->top_field = !(data_pkt[2] & 1);
  			data_pkt += 4;
  			data_len -= 4;
  		}
  	}
  	/* NOTE: With bulk transfers, intermediate data packets
  	 * have no continuation header */
  
  	if (v4l2->capture_type == 0) {
  		vbi_buf = finish_field_prepare_next(dev, vbi_buf, vbi_dma_q);
  		dev->usb_ctl.vbi_buf = vbi_buf;
  		v4l2->capture_type = 1;
  	}
  
  	if (v4l2->capture_type == 1) {
  		int vbi_size = v4l2->vbi_width * v4l2->vbi_height;
  		int vbi_data_len = ((v4l2->vbi_read + data_len) > vbi_size) ?
  				   (vbi_size - v4l2->vbi_read) : data_len;
  
  		/* Copy VBI data */
  		if (vbi_buf != NULL)
  			em28xx_copy_vbi(dev, vbi_buf, data_pkt, vbi_data_len);
  		v4l2->vbi_read += vbi_data_len;
  
  		if (vbi_data_len < data_len) {
  			/* Continue with copying video data */
  			v4l2->capture_type = 2;
  			data_pkt += vbi_data_len;
  			data_len -= vbi_data_len;
  		}
  	}
  
  	if (v4l2->capture_type == 2) {
  		buf = finish_field_prepare_next(dev, buf, dma_q);
  		dev->usb_ctl.vid_buf = buf;
  		v4l2->capture_type = 3;
  	}
  
  	if (v4l2->capture_type == 3 && buf != NULL && data_len > 0)
  		em28xx_copy_video(dev, buf, data_pkt, data_len);
  }
  
  /*
   * Process data packet according to the em25xx/em276x/7x/8x frame data format
   */
  static inline void process_frame_data_em25xx(struct em28xx *dev,
  					     unsigned char *data_pkt,
  					     unsigned int  data_len)
  {
  	struct em28xx_buffer    *buf = dev->usb_ctl.vid_buf;
  	struct em28xx_dmaqueue  *dmaq = &dev->vidq;
  	struct em28xx_v4l2      *v4l2 = dev->v4l2;
  	bool frame_end = false;
  
  	/* Check for header */
  	/* NOTE: at least with bulk transfers, only the first packet
  	 * has a header and has always set the FRAME_END bit         */
  	if (data_len >= 2) {	/* em25xx header is only 2 bytes long */
  		if ((data_pkt[0] == EM25XX_FRMDATAHDR_BYTE1) &&
  		    ((data_pkt[1] & ~EM25XX_FRMDATAHDR_BYTE2_MASK) == 0x00)) {
  			v4l2->top_field = !(data_pkt[1] &
  					   EM25XX_FRMDATAHDR_BYTE2_FRAME_ID);
  			frame_end = data_pkt[1] &
  				    EM25XX_FRMDATAHDR_BYTE2_FRAME_END;
  			data_pkt += 2;
  			data_len -= 2;
  		}
  
  		/* Finish field and prepare next (BULK only) */
  		if (dev->analog_xfer_bulk && frame_end) {
  			buf = finish_field_prepare_next(dev, buf, dmaq);
  			dev->usb_ctl.vid_buf = buf;
  		}
  		/* NOTE: in ISOC mode when a new frame starts and buf==NULL,
  		 * we COULD already prepare a buffer here to avoid skipping the
  		 * first frame.
  		 */
  	}
  
  	/* Copy data */
  	if (buf != NULL && data_len > 0)
  		em28xx_copy_video(dev, buf, data_pkt, data_len);
  
  	/* Finish frame (ISOC only) => avoids lag of 1 frame */
  	if (!dev->analog_xfer_bulk && frame_end) {
  		buf = finish_field_prepare_next(dev, buf, dmaq);
  		dev->usb_ctl.vid_buf = buf;
  	}
  
  	/* NOTE: Tested with USB bulk transfers only !
  	 * The wording in the datasheet suggests that isoc might work different.
  	 * The current code assumes that with isoc transfers each packet has a
  	 * header like with the other em28xx devices.
  	 */
  	/* NOTE: Support for interlaced mode is pure theory. It has not been
  	 * tested and it is unknown if these devices actually support it. */
  	/* NOTE: No VBI support yet (these chips likely do not support VBI). */
  }
  
  /* Processes and copies the URB data content (video and VBI data) */
  static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
  {
  	int xfer_bulk, num_packets, i;
  	unsigned char *usb_data_pkt;
  	unsigned int usb_data_len;
  
  	if (!dev)
  		return 0;
  
  	if (dev->disconnected)
  		return 0;
  
  	if (urb->status < 0)
  		print_err_status(dev, -1, urb->status);
  
  	xfer_bulk = usb_pipebulk(urb->pipe);
  
  	if (xfer_bulk) /* bulk */
  		num_packets = 1;
  	else /* isoc */
  		num_packets = urb->number_of_packets;
  
  	for (i = 0; i < num_packets; i++) {
  		if (xfer_bulk) { /* bulk */
  			usb_data_len = urb->actual_length;
  
  			usb_data_pkt = urb->transfer_buffer;
  		} else { /* isoc */
  			if (urb->iso_frame_desc[i].status < 0) {
  				print_err_status(dev, i,
  						 urb->iso_frame_desc[i].status);
  				if (urb->iso_frame_desc[i].status != -EPROTO)
  					continue;
  			}
  
  			usb_data_len = urb->iso_frame_desc[i].actual_length;
  			if (usb_data_len > dev->max_pkt_size) {
  				em28xx_isocdbg("packet bigger than packet size");
  				continue;
  			}
  
  			usb_data_pkt = urb->transfer_buffer +
  				       urb->iso_frame_desc[i].offset;
  		}
  
  		if (usb_data_len == 0) {
  			/* NOTE: happens very often with isoc transfers */
  			/* em28xx_usbdbg("packet %d is empty",i); - spammy */
  			continue;
  		}
  
  		if (dev->is_em25xx)
  			process_frame_data_em25xx(dev,
  						  usb_data_pkt, usb_data_len);
  		else
  			process_frame_data_em28xx(dev,
  						  usb_data_pkt, usb_data_len);
  
  	}
  	return 1;
  }
  
  static int get_ressource(enum v4l2_buf_type f_type)
  {
  	switch (f_type) {
  	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
  		return EM28XX_RESOURCE_VIDEO;
  	case V4L2_BUF_TYPE_VBI_CAPTURE:
  		return EM28XX_RESOURCE_VBI;
  	default:
  		BUG();
  	}
  }
  
  /* Usage lock check functions */
  static int res_get(struct em28xx *dev, enum v4l2_buf_type f_type)
  {
  	int res_type = get_ressource(f_type);
  
  	/* is it free? */
  	if (dev->resources & res_type) {
  		/* no, someone else uses it */
  		return -EBUSY;
  	}
  
  	/* it's free, grab it */
  	dev->resources |= res_type;
  	em28xx_videodbg("res: get %d\n", res_type);
  	return 0;
  }
  
  static void res_free(struct em28xx *dev, enum v4l2_buf_type f_type)
  {
  	int res_type = get_ressource(f_type);
  
  	dev->resources &= ~res_type;
  	em28xx_videodbg("res: put %d\n", res_type);
  }
  
  static void em28xx_v4l2_media_release(struct em28xx *dev)
  {
  #ifdef CONFIG_MEDIA_CONTROLLER
  	int i;
  
  	for (i = 0; i < MAX_EM28XX_INPUT; i++) {
  		if (!INPUT(i)->type)
  			return;
  		media_device_unregister_entity(&dev->input_ent[i]);
  	}
  #endif
  }
  
  /*
   * Media Controller helper functions
   */
  
  static int em28xx_enable_analog_tuner(struct em28xx *dev)
  {
  #ifdef CONFIG_MEDIA_CONTROLLER
  	struct media_device *mdev = dev->media_dev;
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	struct media_entity *source;
  	struct media_link *link, *found_link = NULL;
  	int ret, active_links = 0;
  
  	if (!mdev || !v4l2->decoder)
  		return 0;
  
  	/*
  	 * This will find the tuner that is connected into the decoder.
  	 * Technically, this is not 100% correct, as the device may be
  	 * using an analog input instead of the tuner. However, as we can't
  	 * do DVB streaming while the DMA engine is being used for V4L2,
  	 * this should be enough for the actual needs.
  	 */
  	list_for_each_entry(link, &v4l2->decoder->links, list) {
  		if (link->sink->entity == v4l2->decoder) {
  			found_link = link;
  			if (link->flags & MEDIA_LNK_FL_ENABLED)
  				active_links++;
  			break;
  		}
  	}
  
  	if (active_links == 1 || !found_link)
  		return 0;
  
  	source = found_link->source->entity;
  	list_for_each_entry(link, &source->links, list) {
  		struct media_entity *sink;
  		int flags = 0;
  
  		sink = link->sink->entity;
  
  		if (sink == v4l2->decoder)
  			flags = MEDIA_LNK_FL_ENABLED;
  
  		ret = media_entity_setup_link(link, flags);
  		if (ret) {
  			pr_err("Couldn't change link %s->%s to %s. Error %d\n",
  			       source->name, sink->name,
  			       flags ? "enabled" : "disabled",
  			       ret);
  			return ret;
  		} else
  			em28xx_videodbg("link %s->%s was %s\n",
  					source->name, sink->name,
  					flags ? "ENABLED" : "disabled");
  	}
  #endif
  	return 0;
  }
  
  static const char * const iname[] = {
  	[EM28XX_VMUX_COMPOSITE]  = "Composite",
  	[EM28XX_VMUX_SVIDEO]     = "S-Video",
  	[EM28XX_VMUX_TELEVISION] = "Television",
  	[EM28XX_RADIO]           = "Radio",
  };
  
  static void em28xx_v4l2_create_entities(struct em28xx *dev)
  {
  #if defined(CONFIG_MEDIA_CONTROLLER)
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	int ret, i;
  
  	/* Initialize Video, VBI and Radio pads */
  	v4l2->video_pad.flags = MEDIA_PAD_FL_SINK;
  	ret = media_entity_pads_init(&v4l2->vdev.entity, 1, &v4l2->video_pad);
  	if (ret < 0)
  		pr_err("failed to initialize video media entity!\n");
  
  	if (em28xx_vbi_supported(dev)) {
  		v4l2->vbi_pad.flags = MEDIA_PAD_FL_SINK;
  		ret = media_entity_pads_init(&v4l2->vbi_dev.entity, 1,
  					     &v4l2->vbi_pad);
  		if (ret < 0)
  			pr_err("failed to initialize vbi media entity!\n");
  	}
  
  	/* Webcams don't have input connectors */
  	if (dev->board.is_webcam)
  		return;
  
  	/* Create entities for each input connector */
  	for (i = 0; i < MAX_EM28XX_INPUT; i++) {
  		struct media_entity *ent = &dev->input_ent[i];
  
  		if (!INPUT(i)->type)
  			break;
  
  		ent->name = iname[INPUT(i)->type];
  		ent->flags = MEDIA_ENT_FL_CONNECTOR;
  		dev->input_pad[i].flags = MEDIA_PAD_FL_SOURCE;
  
  		switch (INPUT(i)->type) {
  		case EM28XX_VMUX_COMPOSITE:
  			ent->function = MEDIA_ENT_F_CONN_COMPOSITE;
  			break;
  		case EM28XX_VMUX_SVIDEO:
  			ent->function = MEDIA_ENT_F_CONN_SVIDEO;
  			break;
  		default: /* EM28XX_VMUX_TELEVISION or EM28XX_RADIO */
  			if (dev->tuner_type != TUNER_ABSENT)
  				ent->function = MEDIA_ENT_F_CONN_RF;
  			break;
  		}
  
  		ret = media_entity_pads_init(ent, 1, &dev->input_pad[i]);
  		if (ret < 0)
  			pr_err("failed to initialize input pad[%d]!\n", i);
  
  		ret = media_device_register_entity(dev->media_dev, ent);
  		if (ret < 0)
  			pr_err("failed to register input entity %d!\n", i);
  	}
  #endif
  }
  
  
  /* ------------------------------------------------------------------
  	Videobuf2 operations
     ------------------------------------------------------------------*/
  
  static int queue_setup(struct vb2_queue *vq,
  		       unsigned int *nbuffers, unsigned int *nplanes,
  		       unsigned int sizes[], void *alloc_ctxs[])
  {
  	struct em28xx *dev = vb2_get_drv_priv(vq);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	unsigned long size =
  		    (v4l2->width * v4l2->height * v4l2->format->depth + 7) >> 3;
  
  	if (*nplanes)
  		return sizes[0] < size ? -EINVAL : 0;
  	*nplanes = 1;
  	sizes[0] = size;
  
  	em28xx_enable_analog_tuner(dev);
  
  	return 0;
  }
  
  static int
  buffer_prepare(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct em28xx        *dev = vb2_get_drv_priv(vb->vb2_queue);
  	struct em28xx_v4l2   *v4l2 = dev->v4l2;
  	unsigned long size;
  
  	em28xx_videodbg("%s, field=%d\n", __func__, vbuf->field);
  
  	size = (v4l2->width * v4l2->height * v4l2->format->depth + 7) >> 3;
  
  	if (vb2_plane_size(vb, 0) < size) {
  		em28xx_videodbg("%s data will not fit into plane (%lu < %lu)\n",
  				__func__, vb2_plane_size(vb, 0), size);
  		return -EINVAL;
  	}
  	vb2_set_plane_payload(vb, 0, size);
  
  	return 0;
  }
  
  int em28xx_start_analog_streaming(struct vb2_queue *vq, unsigned int count)
  {
  	struct em28xx *dev = vb2_get_drv_priv(vq);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	struct v4l2_frequency f;
  	struct v4l2_fh *owner;
  	int rc = 0;
  
  	em28xx_videodbg("%s\n", __func__);
  
  	/* Make sure streaming is not already in progress for this type
  	   of filehandle (e.g. video, vbi) */
  	rc = res_get(dev, vq->type);
  	if (rc)
  		return rc;
  
  	if (v4l2->streaming_users == 0) {
  		/* First active streaming user, so allocate all the URBs */
  
  		/* Allocate the USB bandwidth */
  		em28xx_set_alternate(dev);
  
  		/* Needed, since GPIO might have disabled power of
  		   some i2c device
  		*/
  		em28xx_wake_i2c(dev);
  
  		v4l2->capture_type = -1;
  		rc = em28xx_init_usb_xfer(dev, EM28XX_ANALOG_MODE,
  					  dev->analog_xfer_bulk,
  					  EM28XX_NUM_BUFS,
  					  dev->max_pkt_size,
  					  dev->packet_multiplier,
  					  em28xx_urb_data_copy);
  		if (rc < 0)
  			return rc;
  
  		/*
  		 * djh: it's not clear whether this code is still needed.  I'm
  		 * leaving it in here for now entirely out of concern for
  		 * backward compatibility (the old code did it)
  		 */
  
  		/* Ask tuner to go to analog or radio mode */
  		memset(&f, 0, sizeof(f));
  		f.frequency = v4l2->frequency;
  		owner = (struct v4l2_fh *)vq->owner;
  		if (owner && owner->vdev->vfl_type == VFL_TYPE_RADIO)
  			f.type = V4L2_TUNER_RADIO;
  		else
  			f.type = V4L2_TUNER_ANALOG_TV;
  		v4l2_device_call_all(&v4l2->v4l2_dev,
  				     0, tuner, s_frequency, &f);
  
  		/* Enable video stream at TV decoder */
  		v4l2_device_call_all(&v4l2->v4l2_dev, 0, video, s_stream, 1);
  	}
  
  	v4l2->streaming_users++;
  
  	return rc;
  }
  
  static void em28xx_stop_streaming(struct vb2_queue *vq)
  {
  	struct em28xx *dev = vb2_get_drv_priv(vq);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	struct em28xx_dmaqueue *vidq = &dev->vidq;
  	unsigned long flags = 0;
  
  	em28xx_videodbg("%s\n", __func__);
  
  	res_free(dev, vq->type);
  
  	if (v4l2->streaming_users-- == 1) {
  		/* Disable video stream at TV decoder */
  		v4l2_device_call_all(&v4l2->v4l2_dev, 0, video, s_stream, 0);
  
  		/* Last active user, so shutdown all the URBS */
  		em28xx_uninit_usb_xfer(dev, EM28XX_ANALOG_MODE);
  	}
  
  	spin_lock_irqsave(&dev->slock, flags);
  	if (dev->usb_ctl.vid_buf != NULL) {
  		vb2_buffer_done(&dev->usb_ctl.vid_buf->vb.vb2_buf,
  				VB2_BUF_STATE_ERROR);
  		dev->usb_ctl.vid_buf = NULL;
  	}
  	while (!list_empty(&vidq->active)) {
  		struct em28xx_buffer *buf;
  
  		buf = list_entry(vidq->active.next, struct em28xx_buffer, list);
  		list_del(&buf->list);
  		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
  	}
  	spin_unlock_irqrestore(&dev->slock, flags);
  }
  
  void em28xx_stop_vbi_streaming(struct vb2_queue *vq)
  {
  	struct em28xx *dev = vb2_get_drv_priv(vq);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  	unsigned long flags = 0;
  
  	em28xx_videodbg("%s\n", __func__);
  
  	res_free(dev, vq->type);
  
  	if (v4l2->streaming_users-- == 1) {
  		/* Disable video stream at TV decoder */
  		v4l2_device_call_all(&v4l2->v4l2_dev, 0, video, s_stream, 0);
  
  		/* Last active user, so shutdown all the URBS */
  		em28xx_uninit_usb_xfer(dev, EM28XX_ANALOG_MODE);
  	}
  
  	spin_lock_irqsave(&dev->slock, flags);
  	if (dev->usb_ctl.vbi_buf != NULL) {
  		vb2_buffer_done(&dev->usb_ctl.vbi_buf->vb.vb2_buf,
  				VB2_BUF_STATE_ERROR);
  		dev->usb_ctl.vbi_buf = NULL;
  	}
  	while (!list_empty(&vbiq->active)) {
  		struct em28xx_buffer *buf;
  
  		buf = list_entry(vbiq->active.next, struct em28xx_buffer, list);
  		list_del(&buf->list);
  		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
  	}
  	spin_unlock_irqrestore(&dev->slock, flags);
  }
  
  static void
  buffer_queue(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  	struct em28xx_buffer *buf =
  		container_of(vbuf, struct em28xx_buffer, vb);
  	struct em28xx_dmaqueue *vidq = &dev->vidq;
  	unsigned long flags = 0;
  
  	em28xx_videodbg("%s\n", __func__);
  	buf->mem = vb2_plane_vaddr(vb, 0);
  	buf->length = vb2_plane_size(vb, 0);
  
  	spin_lock_irqsave(&dev->slock, flags);
  	list_add_tail(&buf->list, &vidq->active);
  	spin_unlock_irqrestore(&dev->slock, flags);
  }
  
  static struct vb2_ops em28xx_video_qops = {
  	.queue_setup    = queue_setup,
  	.buf_prepare    = buffer_prepare,
  	.buf_queue      = buffer_queue,
  	.start_streaming = em28xx_start_analog_streaming,
  	.stop_streaming = em28xx_stop_streaming,
  	.wait_prepare   = vb2_ops_wait_prepare,
  	.wait_finish    = vb2_ops_wait_finish,
  };
  
  static int em28xx_vb2_setup(struct em28xx *dev)
  {
  	int rc;
  	struct vb2_queue *q;
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	/* Setup Videobuf2 for Video capture */
  	q = &v4l2->vb_vidq;
  	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  	q->io_modes = VB2_READ | VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
  	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	q->drv_priv = dev;
  	q->buf_struct_size = sizeof(struct em28xx_buffer);
  	q->ops = &em28xx_video_qops;
  	q->mem_ops = &vb2_vmalloc_memops;
  
  	rc = vb2_queue_init(q);
  	if (rc < 0)
  		return rc;
  
  	/* Setup Videobuf2 for VBI capture */
  	q = &v4l2->vb_vbiq;
  	q->type = V4L2_BUF_TYPE_VBI_CAPTURE;
  	q->io_modes = VB2_READ | VB2_MMAP | VB2_USERPTR;
  	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	q->drv_priv = dev;
  	q->buf_struct_size = sizeof(struct em28xx_buffer);
  	q->ops = &em28xx_vbi_qops;
  	q->mem_ops = &vb2_vmalloc_memops;
  
  	rc = vb2_queue_init(q);
  	if (rc < 0)
  		return rc;
  
  	return 0;
  }
  
  /*********************  v4l2 interface  **************************************/
  
  static void video_mux(struct em28xx *dev, int index)
  {
  	struct v4l2_device *v4l2_dev = &dev->v4l2->v4l2_dev;
  
  	dev->ctl_input = index;
  	dev->ctl_ainput = INPUT(index)->amux;
  	dev->ctl_aoutput = INPUT(index)->aout;
  
  	if (!dev->ctl_aoutput)
  		dev->ctl_aoutput = EM28XX_AOUT_MASTER;
  
  	v4l2_device_call_all(v4l2_dev, 0, video, s_routing,
  			     INPUT(index)->vmux, 0, 0);
  
  	if (dev->board.has_msp34xx) {
  		if (dev->i2s_speed) {
  			v4l2_device_call_all(v4l2_dev, 0, audio,
  					     s_i2s_clock_freq, dev->i2s_speed);
  		}
  		/* Note: this is msp3400 specific */
  		v4l2_device_call_all(v4l2_dev, 0, audio, s_routing,
  				     dev->ctl_ainput,
  				     MSP_OUTPUT(MSP_SC_IN_DSP_SCART1), 0);
  	}
  
  	if (dev->board.adecoder != EM28XX_NOADECODER) {
  		v4l2_device_call_all(v4l2_dev, 0, audio, s_routing,
  				     dev->ctl_ainput, dev->ctl_aoutput, 0);
  	}
  
  	em28xx_audio_analog_set(dev);
  }
  
  static void em28xx_ctrl_notify(struct v4l2_ctrl *ctrl, void *priv)
  {
  	struct em28xx *dev = priv;
  
  	/*
  	 * In the case of non-AC97 volume controls, we still need
  	 * to do some setups at em28xx, in order to mute/unmute
  	 * and to adjust audio volume. However, the value ranges
  	 * should be checked by the corresponding V4L subdriver.
  	 */
  	switch (ctrl->id) {
  	case V4L2_CID_AUDIO_MUTE:
  		dev->mute = ctrl->val;
  		em28xx_audio_analog_set(dev);
  		break;
  	case V4L2_CID_AUDIO_VOLUME:
  		dev->volume = ctrl->val;
  		em28xx_audio_analog_set(dev);
  		break;
  	}
  }
  
  static int em28xx_s_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct em28xx_v4l2 *v4l2 =
  		  container_of(ctrl->handler, struct em28xx_v4l2, ctrl_handler);
  	struct em28xx *dev = v4l2->dev;
  	int ret = -EINVAL;
  
  	switch (ctrl->id) {
  	case V4L2_CID_AUDIO_MUTE:
  		dev->mute = ctrl->val;
  		ret = em28xx_audio_analog_set(dev);
  		break;
  	case V4L2_CID_AUDIO_VOLUME:
  		dev->volume = ctrl->val;
  		ret = em28xx_audio_analog_set(dev);
  		break;
  	case V4L2_CID_CONTRAST:
  		ret = em28xx_write_reg(dev, EM28XX_R20_YGAIN, ctrl->val);
  		break;
  	case V4L2_CID_BRIGHTNESS:
  		ret = em28xx_write_reg(dev, EM28XX_R21_YOFFSET, ctrl->val);
  		break;
  	case V4L2_CID_SATURATION:
  		ret = em28xx_write_reg(dev, EM28XX_R22_UVGAIN, ctrl->val);
  		break;
  	case V4L2_CID_BLUE_BALANCE:
  		ret = em28xx_write_reg(dev, EM28XX_R23_UOFFSET, ctrl->val);
  		break;
  	case V4L2_CID_RED_BALANCE:
  		ret = em28xx_write_reg(dev, EM28XX_R24_VOFFSET, ctrl->val);
  		break;
  	case V4L2_CID_SHARPNESS:
  		ret = em28xx_write_reg(dev, EM28XX_R25_SHARPNESS, ctrl->val);
  		break;
  	}
  
  	return (ret < 0) ? ret : 0;
  }
  
  static const struct v4l2_ctrl_ops em28xx_ctrl_ops = {
  	.s_ctrl = em28xx_s_ctrl,
  };
  
  static void size_to_scale(struct em28xx *dev,
  			  unsigned int width, unsigned int height,
  			unsigned int *hscale, unsigned int *vscale)
  {
  	unsigned int          maxw = norm_maxw(dev);
  	unsigned int          maxh = norm_maxh(dev);
  
  	*hscale = (((unsigned long)maxw) << 12) / width - 4096L;
  	if (*hscale > EM28XX_HVSCALE_MAX)
  		*hscale = EM28XX_HVSCALE_MAX;
  
  	*vscale = (((unsigned long)maxh) << 12) / height - 4096L;
  	if (*vscale > EM28XX_HVSCALE_MAX)
  		*vscale = EM28XX_HVSCALE_MAX;
  }
  
  static void scale_to_size(struct em28xx *dev,
  			  unsigned int hscale, unsigned int vscale,
  			  unsigned int *width, unsigned int *height)
  {
  	unsigned int          maxw = norm_maxw(dev);
  	unsigned int          maxh = norm_maxh(dev);
  
  	*width = (((unsigned long)maxw) << 12) / (hscale + 4096L);
  	*height = (((unsigned long)maxh) << 12) / (vscale + 4096L);
  
  	/* Don't let width or height to be zero */
  	if (*width < 1)
  		*width = 1;
  	if (*height < 1)
  		*height = 1;
  }
  
  /* ------------------------------------------------------------------
  	IOCTL vidioc handling
     ------------------------------------------------------------------*/
  
  static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
  				struct v4l2_format *f)
  {
  	struct em28xx         *dev = video_drvdata(file);
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  
  	f->fmt.pix.width = v4l2->width;
  	f->fmt.pix.height = v4l2->height;
  	f->fmt.pix.pixelformat = v4l2->format->fourcc;
  	f->fmt.pix.bytesperline = (v4l2->width * v4l2->format->depth + 7) >> 3;
  	f->fmt.pix.sizeimage = f->fmt.pix.bytesperline * v4l2->height;
  	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
  
  	/* FIXME: TOP? NONE? BOTTOM? ALTENATE? */
  	if (v4l2->progressive)
  		f->fmt.pix.field = V4L2_FIELD_NONE;
  	else
  		f->fmt.pix.field = v4l2->interlaced_fieldmode ?
  			   V4L2_FIELD_INTERLACED : V4L2_FIELD_TOP;
  	return 0;
  }
  
  static struct em28xx_fmt *format_by_fourcc(unsigned int fourcc)
  {
  	unsigned int i;
  
  	for (i = 0; i < ARRAY_SIZE(format); i++)
  		if (format[i].fourcc == fourcc)
  			return &format[i];
  
  	return NULL;
  }
  
  static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
  				  struct v4l2_format *f)
  {
  	struct em28xx         *dev   = video_drvdata(file);
  	struct em28xx_v4l2    *v4l2  = dev->v4l2;
  	unsigned int          width  = f->fmt.pix.width;
  	unsigned int          height = f->fmt.pix.height;
  	unsigned int          maxw   = norm_maxw(dev);
  	unsigned int          maxh   = norm_maxh(dev);
  	unsigned int          hscale, vscale;
  	struct em28xx_fmt     *fmt;
  
  	fmt = format_by_fourcc(f->fmt.pix.pixelformat);
  	if (!fmt) {
  		em28xx_videodbg("Fourcc format (%08x) invalid.\n",
  				f->fmt.pix.pixelformat);
  		return -EINVAL;
  	}
  
  	if (dev->board.is_em2800) {
  		/* the em2800 can only scale down to 50% */
  		height = height > (3 * maxh / 4) ? maxh : maxh / 2;
  		width = width > (3 * maxw / 4) ? maxw : maxw / 2;
  		/*
  		 * MaxPacketSize for em2800 is too small to capture at full
  		 * resolution use half of maxw as the scaler can only scale
  		 * to 50%
  		 */
  		if (width == maxw && height == maxh)
  			width /= 2;
  	} else {
  		/* width must even because of the YUYV format
  		   height must be even because of interlacing */
  		v4l_bound_align_image(&width, 48, maxw, 1, &height, 32, maxh,
  				      1, 0);
  	}
  	/* Avoid division by zero at size_to_scale */
  	if (width < 1)
  		width = 1;
  	if (height < 1)
  		height = 1;
  
  	size_to_scale(dev, width, height, &hscale, &vscale);
  	scale_to_size(dev, hscale, vscale, &width, &height);
  
  	f->fmt.pix.width = width;
  	f->fmt.pix.height = height;
  	f->fmt.pix.pixelformat = fmt->fourcc;
  	f->fmt.pix.bytesperline = (width * fmt->depth + 7) >> 3;
  	f->fmt.pix.sizeimage = f->fmt.pix.bytesperline * height;
  	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
  	if (v4l2->progressive)
  		f->fmt.pix.field = V4L2_FIELD_NONE;
  	else
  		f->fmt.pix.field = v4l2->interlaced_fieldmode ?
  			   V4L2_FIELD_INTERLACED : V4L2_FIELD_TOP;
  	f->fmt.pix.priv = 0;
  
  	return 0;
  }
  
  static int em28xx_set_video_format(struct em28xx *dev, unsigned int fourcc,
  				   unsigned width, unsigned height)
  {
  	struct em28xx_fmt     *fmt;
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  
  	fmt = format_by_fourcc(fourcc);
  	if (!fmt)
  		return -EINVAL;
  
  	v4l2->format = fmt;
  	v4l2->width  = width;
  	v4l2->height = height;
  
  	/* set new image size */
  	size_to_scale(dev, v4l2->width, v4l2->height,
  		      &v4l2->hscale, &v4l2->vscale);
  
  	em28xx_resolution_set(dev);
  
  	return 0;
  }
  
  static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
  				struct v4l2_format *f)
  {
  	struct em28xx *dev = video_drvdata(file);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	if (vb2_is_busy(&v4l2->vb_vidq))
  		return -EBUSY;
  
  	vidioc_try_fmt_vid_cap(file, priv, f);
  
  	return em28xx_set_video_format(dev, f->fmt.pix.pixelformat,
  				f->fmt.pix.width, f->fmt.pix.height);
  }
  
  static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	*norm = dev->v4l2->norm;
  
  	return 0;
  }
  
  static int vidioc_querystd(struct file *file, void *priv, v4l2_std_id *norm)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	v4l2_device_call_all(&dev->v4l2->v4l2_dev, 0, video, querystd, norm);
  
  	return 0;
  }
  
  static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id norm)
  {
  	struct em28xx      *dev  = video_drvdata(file);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	struct v4l2_format f;
  
  	if (norm == v4l2->norm)
  		return 0;
  
  	if (v4l2->streaming_users > 0)
  		return -EBUSY;
  
  	v4l2->norm = norm;
  
  	/* Adjusts width/height, if needed */
  	f.fmt.pix.width = 720;
  	f.fmt.pix.height = (norm & V4L2_STD_525_60) ? 480 : 576;
  	vidioc_try_fmt_vid_cap(file, priv, &f);
  
  	/* set new image size */
  	v4l2->width = f.fmt.pix.width;
  	v4l2->height = f.fmt.pix.height;
  	size_to_scale(dev, v4l2->width, v4l2->height,
  		      &v4l2->hscale, &v4l2->vscale);
  
  	em28xx_resolution_set(dev);
  	v4l2_device_call_all(&v4l2->v4l2_dev, 0, video, s_std, v4l2->norm);
  
  	return 0;
  }
  
  static int vidioc_g_parm(struct file *file, void *priv,
  			 struct v4l2_streamparm *p)
  {
  	struct em28xx      *dev  = video_drvdata(file);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	int rc = 0;
  
  	p->parm.capture.readbuffers = EM28XX_MIN_BUF;
  	if (dev->board.is_webcam)
  		rc = v4l2_device_call_until_err(&v4l2->v4l2_dev, 0,
  						video, g_parm, p);
  	else
  		v4l2_video_std_frame_period(v4l2->norm,
  					    &p->parm.capture.timeperframe);
  
  	return rc;
  }
  
  static int vidioc_s_parm(struct file *file, void *priv,
  			 struct v4l2_streamparm *p)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	p->parm.capture.readbuffers = EM28XX_MIN_BUF;
  	return v4l2_device_call_until_err(&dev->v4l2->v4l2_dev,
  					  0, video, s_parm, p);
  }
  
  static int vidioc_enum_input(struct file *file, void *priv,
  			     struct v4l2_input *i)
  {
  	struct em28xx *dev = video_drvdata(file);
  	unsigned int       n;
  
  	n = i->index;
  	if (n >= MAX_EM28XX_INPUT)
  		return -EINVAL;
  	if (0 == INPUT(n)->type)
  		return -EINVAL;
  
  	i->index = n;
  	i->type = V4L2_INPUT_TYPE_CAMERA;
  
  	strcpy(i->name, iname[INPUT(n)->type]);
  
  	if ((EM28XX_VMUX_TELEVISION == INPUT(n)->type))
  		i->type = V4L2_INPUT_TYPE_TUNER;
  
  	i->std = dev->v4l2->vdev.tvnorms;
  	/* webcams do not have the STD API */
  	if (dev->board.is_webcam)
  		i->capabilities = 0;
  
  	return 0;
  }
  
  static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	*i = dev->ctl_input;
  
  	return 0;
  }
  
  static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (i >= MAX_EM28XX_INPUT)
  		return -EINVAL;
  	if (0 == INPUT(i)->type)
  		return -EINVAL;
  
  	video_mux(dev, i);
  	return 0;
  }
  
  static int vidioc_g_audio(struct file *file, void *priv, struct v4l2_audio *a)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	switch (a->index) {
  	case EM28XX_AMUX_VIDEO:
  		strcpy(a->name, "Television");
  		break;
  	case EM28XX_AMUX_LINE_IN:
  		strcpy(a->name, "Line In");
  		break;
  	case EM28XX_AMUX_VIDEO2:
  		strcpy(a->name, "Television alt");
  		break;
  	case EM28XX_AMUX_PHONE:
  		strcpy(a->name, "Phone");
  		break;
  	case EM28XX_AMUX_MIC:
  		strcpy(a->name, "Mic");
  		break;
  	case EM28XX_AMUX_CD:
  		strcpy(a->name, "CD");
  		break;
  	case EM28XX_AMUX_AUX:
  		strcpy(a->name, "Aux");
  		break;
  	case EM28XX_AMUX_PCM_OUT:
  		strcpy(a->name, "PCM");
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	a->index = dev->ctl_ainput;
  	a->capability = V4L2_AUDCAP_STEREO;
  
  	return 0;
  }
  
  static int vidioc_s_audio(struct file *file, void *priv, const struct v4l2_audio *a)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (a->index >= MAX_EM28XX_INPUT)
  		return -EINVAL;
  	if (0 == INPUT(a->index)->type)
  		return -EINVAL;
  
  	dev->ctl_ainput = INPUT(a->index)->amux;
  	dev->ctl_aoutput = INPUT(a->index)->aout;
  
  	if (!dev->ctl_aoutput)
  		dev->ctl_aoutput = EM28XX_AOUT_MASTER;
  
  	return 0;
  }
  
  static int vidioc_g_tuner(struct file *file, void *priv,
  			  struct v4l2_tuner *t)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (0 != t->index)
  		return -EINVAL;
  
  	strcpy(t->name, "Tuner");
  
  	v4l2_device_call_all(&dev->v4l2->v4l2_dev, 0, tuner, g_tuner, t);
  	return 0;
  }
  
  static int vidioc_s_tuner(struct file *file, void *priv,
  			  const struct v4l2_tuner *t)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (0 != t->index)
  		return -EINVAL;
  
  	v4l2_device_call_all(&dev->v4l2->v4l2_dev, 0, tuner, s_tuner, t);
  	return 0;
  }
  
  static int vidioc_g_frequency(struct file *file, void *priv,
  			      struct v4l2_frequency *f)
  {
  	struct em28xx         *dev = video_drvdata(file);
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  
  	if (0 != f->tuner)
  		return -EINVAL;
  
  	f->frequency = v4l2->frequency;
  	return 0;
  }
  
  static int vidioc_s_frequency(struct file *file, void *priv,
  			      const struct v4l2_frequency *f)
  {
  	struct v4l2_frequency  new_freq = *f;
  	struct em28xx             *dev  = video_drvdata(file);
  	struct em28xx_v4l2        *v4l2 = dev->v4l2;
  
  	if (0 != f->tuner)
  		return -EINVAL;
  
  	v4l2_device_call_all(&v4l2->v4l2_dev, 0, tuner, s_frequency, f);
  	v4l2_device_call_all(&v4l2->v4l2_dev, 0, tuner, g_frequency, &new_freq);
  	v4l2->frequency = new_freq.frequency;
  
  	return 0;
  }
  
  #ifdef CONFIG_VIDEO_ADV_DEBUG
  static int vidioc_g_chip_info(struct file *file, void *priv,
  			      struct v4l2_dbg_chip_info *chip)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (chip->match.addr > 1)
  		return -EINVAL;
  	if (chip->match.addr == 1)
  		strlcpy(chip->name, "ac97", sizeof(chip->name));
  	else
  		strlcpy(chip->name,
  			dev->v4l2->v4l2_dev.name, sizeof(chip->name));
  	return 0;
  }
  
  static int em28xx_reg_len(int reg)
  {
  	switch (reg) {
  	case EM28XX_R40_AC97LSB:
  	case EM28XX_R30_HSCALELOW:
  	case EM28XX_R32_VSCALELOW:
  		return 2;
  	default:
  		return 1;
  	}
  }
  
  static int vidioc_g_register(struct file *file, void *priv,
  			     struct v4l2_dbg_register *reg)
  {
  	struct em28xx *dev = video_drvdata(file);
  	int ret;
  
  	if (reg->match.addr > 1)
  		return -EINVAL;
  	if (reg->match.addr) {
  		ret = em28xx_read_ac97(dev, reg->reg);
  		if (ret < 0)
  			return ret;
  
  		reg->val = ret;
  		reg->size = 1;
  		return 0;
  	}
  
  	/* Match host */
  	reg->size = em28xx_reg_len(reg->reg);
  	if (reg->size == 1) {
  		ret = em28xx_read_reg(dev, reg->reg);
  
  		if (ret < 0)
  			return ret;
  
  		reg->val = ret;
  	} else {
  		__le16 val = 0;
  
  		ret = dev->em28xx_read_reg_req_len(dev, USB_REQ_GET_STATUS,
  						   reg->reg, (char *)&val, 2);
  		if (ret < 0)
  			return ret;
  
  		reg->val = le16_to_cpu(val);
  	}
  
  	return 0;
  }
  
  static int vidioc_s_register(struct file *file, void *priv,
  			     const struct v4l2_dbg_register *reg)
  {
  	struct em28xx *dev = video_drvdata(file);
  	__le16 buf;
  
  	if (reg->match.addr > 1)
  		return -EINVAL;
  	if (reg->match.addr)
  		return em28xx_write_ac97(dev, reg->reg, reg->val);
  
  	/* Match host */
  	buf = cpu_to_le16(reg->val);
  
  	return em28xx_write_regs(dev, reg->reg, (char *)&buf,
  			       em28xx_reg_len(reg->reg));
  }
  #endif
  
  static int vidioc_querycap(struct file *file, void  *priv,
  			   struct v4l2_capability *cap)
  {
  	struct video_device   *vdev = video_devdata(file);
  	struct em28xx         *dev  = video_drvdata(file);
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  
  	strlcpy(cap->driver, "em28xx", sizeof(cap->driver));
  	strlcpy(cap->card, em28xx_boards[dev->model].name, sizeof(cap->card));
  	usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
  
  	if (vdev->vfl_type == VFL_TYPE_GRABBER)
  		cap->device_caps = V4L2_CAP_READWRITE |
  			V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
  	else if (vdev->vfl_type == VFL_TYPE_RADIO)
  		cap->device_caps = V4L2_CAP_RADIO;
  	else
  		cap->device_caps = V4L2_CAP_READWRITE | V4L2_CAP_VBI_CAPTURE;
  
  	if (dev->int_audio_type != EM28XX_INT_AUDIO_NONE)
  		cap->device_caps |= V4L2_CAP_AUDIO;
  
  	if (dev->tuner_type != TUNER_ABSENT)
  		cap->device_caps |= V4L2_CAP_TUNER;
  
  	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS |
  		V4L2_CAP_READWRITE | V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
  	if (video_is_registered(&v4l2->vbi_dev))
  		cap->capabilities |= V4L2_CAP_VBI_CAPTURE;
  	if (video_is_registered(&v4l2->radio_dev))
  		cap->capabilities |= V4L2_CAP_RADIO;
  	return 0;
  }
  
  static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
  				   struct v4l2_fmtdesc *f)
  {
  	if (unlikely(f->index >= ARRAY_SIZE(format)))
  		return -EINVAL;
  
  	strlcpy(f->description, format[f->index].name, sizeof(f->description));
  	f->pixelformat = format[f->index].fourcc;
  
  	return 0;
  }
  
  static int vidioc_enum_framesizes(struct file *file, void *priv,
  				  struct v4l2_frmsizeenum *fsize)
  {
  	struct em28xx         *dev = video_drvdata(file);
  	struct em28xx_fmt     *fmt;
  	unsigned int	      maxw = norm_maxw(dev);
  	unsigned int	      maxh = norm_maxh(dev);
  
  	fmt = format_by_fourcc(fsize->pixel_format);
  	if (!fmt) {
  		em28xx_videodbg("Fourcc format (%08x) invalid.\n",
  				fsize->pixel_format);
  		return -EINVAL;
  	}
  
  	if (dev->board.is_em2800) {
  		if (fsize->index > 1)
  			return -EINVAL;
  		fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
  		fsize->discrete.width = maxw / (1 + fsize->index);
  		fsize->discrete.height = maxh / (1 + fsize->index);
  		return 0;
  	}
  
  	if (fsize->index != 0)
  		return -EINVAL;
  
  	/* Report a continuous range */
  	fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
  	scale_to_size(dev, EM28XX_HVSCALE_MAX, EM28XX_HVSCALE_MAX,
  		      &fsize->stepwise.min_width, &fsize->stepwise.min_height);
  	if (fsize->stepwise.min_width < 48)
  		fsize->stepwise.min_width = 48;
  	if (fsize->stepwise.min_height < 38)
  		fsize->stepwise.min_height = 38;
  	fsize->stepwise.max_width = maxw;
  	fsize->stepwise.max_height = maxh;
  	fsize->stepwise.step_width = 1;
  	fsize->stepwise.step_height = 1;
  	return 0;
  }
  
  /* RAW VBI ioctls */
  
  static int vidioc_g_fmt_vbi_cap(struct file *file, void *priv,
  				struct v4l2_format *format)
  {
  	struct em28xx         *dev  = video_drvdata(file);
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  
  	format->fmt.vbi.samples_per_line = v4l2->vbi_width;
  	format->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
  	format->fmt.vbi.offset = 0;
  	format->fmt.vbi.flags = 0;
  	format->fmt.vbi.sampling_rate = 6750000 * 4 / 2;
  	format->fmt.vbi.count[0] = v4l2->vbi_height;
  	format->fmt.vbi.count[1] = v4l2->vbi_height;
  	memset(format->fmt.vbi.reserved, 0, sizeof(format->fmt.vbi.reserved));
  
  	/* Varies by video standard (NTSC, PAL, etc.) */
  	if (v4l2->norm & V4L2_STD_525_60) {
  		/* NTSC */
  		format->fmt.vbi.start[0] = 10;
  		format->fmt.vbi.start[1] = 273;
  	} else if (v4l2->norm & V4L2_STD_625_50) {
  		/* PAL */
  		format->fmt.vbi.start[0] = 6;
  		format->fmt.vbi.start[1] = 318;
  	}
  
  	return 0;
  }
  
  /* ----------------------------------------------------------- */
  /* RADIO ESPECIFIC IOCTLS                                      */
  /* ----------------------------------------------------------- */
  
  static int radio_g_tuner(struct file *file, void *priv,
  			 struct v4l2_tuner *t)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (unlikely(t->index > 0))
  		return -EINVAL;
  
  	strcpy(t->name, "Radio");
  
  	v4l2_device_call_all(&dev->v4l2->v4l2_dev, 0, tuner, g_tuner, t);
  
  	return 0;
  }
  
  static int radio_s_tuner(struct file *file, void *priv,
  			 const struct v4l2_tuner *t)
  {
  	struct em28xx *dev = video_drvdata(file);
  
  	if (0 != t->index)
  		return -EINVAL;
  
  	v4l2_device_call_all(&dev->v4l2->v4l2_dev, 0, tuner, s_tuner, t);
  
  	return 0;
  }
  
  /*
   * em28xx_free_v4l2() - Free struct em28xx_v4l2
   *
   * @ref: struct kref for struct em28xx_v4l2
   *
   * Called when all users of struct em28xx_v4l2 are gone
   */
  static void em28xx_free_v4l2(struct kref *ref)
  {
  	struct em28xx_v4l2 *v4l2 = container_of(ref, struct em28xx_v4l2, ref);
  
  	v4l2->dev->v4l2 = NULL;
  	kfree(v4l2);
  }
  
  /*
   * em28xx_v4l2_open()
   * inits the device and starts isoc transfer
   */
  static int em28xx_v4l2_open(struct file *filp)
  {
  	struct video_device *vdev = video_devdata(filp);
  	struct em28xx *dev = video_drvdata(filp);
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  	enum v4l2_buf_type fh_type = 0;
  	int ret;
  
  	switch (vdev->vfl_type) {
  	case VFL_TYPE_GRABBER:
  		fh_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  		break;
  	case VFL_TYPE_VBI:
  		fh_type = V4L2_BUF_TYPE_VBI_CAPTURE;
  		break;
  	case VFL_TYPE_RADIO:
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	em28xx_videodbg("open dev=%s type=%s users=%d\n",
  			video_device_node_name(vdev), v4l2_type_names[fh_type],
  			v4l2->users);
  
  	if (mutex_lock_interruptible(&dev->lock))
  		return -ERESTARTSYS;
  
  	ret = v4l2_fh_open(filp);
  	if (ret) {
  		em28xx_errdev("%s: v4l2_fh_open() returned error %d\n",
  			      __func__, ret);
  		mutex_unlock(&dev->lock);
  		return ret;
  	}
  
  	if (v4l2->users == 0) {
  		em28xx_set_mode(dev, EM28XX_ANALOG_MODE);
  
  		if (vdev->vfl_type != VFL_TYPE_RADIO)
  			em28xx_resolution_set(dev);
  
  		/*
  		 * Needed, since GPIO might have disabled power
  		 * of some i2c devices
  		 */
  		em28xx_wake_i2c(dev);
  	}
  
  	if (vdev->vfl_type == VFL_TYPE_RADIO) {
  		em28xx_videodbg("video_open: setting radio device\n");
  		v4l2_device_call_all(&v4l2->v4l2_dev, 0, tuner, s_radio);
  	}
  
  	kref_get(&dev->ref);
  	kref_get(&v4l2->ref);
  	v4l2->users++;
  
  	mutex_unlock(&dev->lock);
  
  	return 0;
  }
  
  /*
   * em28xx_v4l2_fini()
   * unregisters the v4l2,i2c and usb devices
   * called when the device gets disconected or at module unload
  */
  static int em28xx_v4l2_fini(struct em28xx *dev)
  {
  	struct em28xx_v4l2 *v4l2 = dev->v4l2;
  
  	if (dev->is_audio_only) {
  		/* Shouldn't initialize IR for this interface */
  		return 0;
  	}
  
  	if (!dev->has_video) {
  		/* This device does not support the v4l2 extension */
  		return 0;
  	}
  
  	if (v4l2 == NULL)
  		return 0;
  
  	em28xx_info("Closing video extension\n");
  
  	mutex_lock(&dev->lock);
  
  	v4l2_device_disconnect(&v4l2->v4l2_dev);
  
  	em28xx_uninit_usb_xfer(dev, EM28XX_ANALOG_MODE);
  
  	em28xx_v4l2_media_release(dev);
  
  	if (video_is_registered(&v4l2->radio_dev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->radio_dev));
  		video_unregister_device(&v4l2->radio_dev);
  	}
  	if (video_is_registered(&v4l2->vbi_dev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->vbi_dev));
  		video_unregister_device(&v4l2->vbi_dev);
  	}
  	if (video_is_registered(&v4l2->vdev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->vdev));
  		video_unregister_device(&v4l2->vdev);
  	}
  
  	v4l2_ctrl_handler_free(&v4l2->ctrl_handler);
  	v4l2_device_unregister(&v4l2->v4l2_dev);
  
  	if (v4l2->clk) {
  		v4l2_clk_unregister_fixed(v4l2->clk);
  		v4l2->clk = NULL;
  	}
  
  	kref_put(&v4l2->ref, em28xx_free_v4l2);
  
  	mutex_unlock(&dev->lock);
  
  	kref_put(&dev->ref, em28xx_free_device);
  
  	return 0;
  }
  
  static int em28xx_v4l2_suspend(struct em28xx *dev)
  {
  	if (dev->is_audio_only)
  		return 0;
  
  	if (!dev->has_video)
  		return 0;
  
  	em28xx_info("Suspending video extension\n");
  	em28xx_stop_urbs(dev);
  	return 0;
  }
  
  static int em28xx_v4l2_resume(struct em28xx *dev)
  {
  	if (dev->is_audio_only)
  		return 0;
  
  	if (!dev->has_video)
  		return 0;
  
  	em28xx_info("Resuming video extension\n");
  	/* what do we do here */
  	return 0;
  }
  
  /*
   * em28xx_v4l2_close()
   * stops streaming and deallocates all resources allocated by the v4l2
   * calls and ioctls
   */
  static int em28xx_v4l2_close(struct file *filp)
  {
  	struct em28xx         *dev  = video_drvdata(filp);
  	struct em28xx_v4l2    *v4l2 = dev->v4l2;
  	int              errCode;
  
  	em28xx_videodbg("users=%d\n", v4l2->users);
  
  	vb2_fop_release(filp);
  	mutex_lock(&dev->lock);
  
  	if (v4l2->users == 1) {
  		/* No sense to try to write to the device */
  		if (dev->disconnected)
  			goto exit;
  
  		/* Save some power by putting tuner to sleep */
  		v4l2_device_call_all(&v4l2->v4l2_dev, 0, core, s_power, 0);
  
  		/* do this before setting alternate! */
  		em28xx_set_mode(dev, EM28XX_SUSPEND);
  
  		/* set alternate 0 */
  		dev->alt = 0;
  		em28xx_videodbg("setting alternate 0\n");
  		errCode = usb_set_interface(dev->udev, 0, 0);
  		if (errCode < 0) {
  			em28xx_errdev("cannot change alternate number to "
  					"0 (error=%i)\n", errCode);
  		}
  	}
  
  exit:
  	v4l2->users--;
  	kref_put(&v4l2->ref, em28xx_free_v4l2);
  	mutex_unlock(&dev->lock);
  	kref_put(&dev->ref, em28xx_free_device);
  
  	return 0;
  }
  
  static const struct v4l2_file_operations em28xx_v4l_fops = {
  	.owner         = THIS_MODULE,
  	.open          = em28xx_v4l2_open,
  	.release       = em28xx_v4l2_close,
  	.read          = vb2_fop_read,
  	.poll          = vb2_fop_poll,
  	.mmap          = vb2_fop_mmap,
  	.unlocked_ioctl = video_ioctl2,
  };
  
  static const struct v4l2_ioctl_ops video_ioctl_ops = {
  	.vidioc_querycap            = vidioc_querycap,
  	.vidioc_enum_fmt_vid_cap    = vidioc_enum_fmt_vid_cap,
  	.vidioc_g_fmt_vid_cap       = vidioc_g_fmt_vid_cap,
  	.vidioc_try_fmt_vid_cap     = vidioc_try_fmt_vid_cap,
  	.vidioc_s_fmt_vid_cap       = vidioc_s_fmt_vid_cap,
  	.vidioc_g_fmt_vbi_cap       = vidioc_g_fmt_vbi_cap,
  	.vidioc_try_fmt_vbi_cap     = vidioc_g_fmt_vbi_cap,
  	.vidioc_s_fmt_vbi_cap       = vidioc_g_fmt_vbi_cap,
  	.vidioc_enum_framesizes     = vidioc_enum_framesizes,
  	.vidioc_g_audio             = vidioc_g_audio,
  	.vidioc_s_audio             = vidioc_s_audio,
  
  	.vidioc_reqbufs             = vb2_ioctl_reqbufs,
  	.vidioc_create_bufs         = vb2_ioctl_create_bufs,
  	.vidioc_prepare_buf         = vb2_ioctl_prepare_buf,
  	.vidioc_querybuf            = vb2_ioctl_querybuf,
  	.vidioc_qbuf                = vb2_ioctl_qbuf,
  	.vidioc_dqbuf               = vb2_ioctl_dqbuf,
  
  	.vidioc_g_std               = vidioc_g_std,
  	.vidioc_querystd            = vidioc_querystd,
  	.vidioc_s_std               = vidioc_s_std,
  	.vidioc_g_parm		    = vidioc_g_parm,
  	.vidioc_s_parm		    = vidioc_s_parm,
  	.vidioc_enum_input          = vidioc_enum_input,
  	.vidioc_g_input             = vidioc_g_input,
  	.vidioc_s_input             = vidioc_s_input,
  	.vidioc_streamon            = vb2_ioctl_streamon,
  	.vidioc_streamoff           = vb2_ioctl_streamoff,
  	.vidioc_g_tuner             = vidioc_g_tuner,
  	.vidioc_s_tuner             = vidioc_s_tuner,
  	.vidioc_g_frequency         = vidioc_g_frequency,
  	.vidioc_s_frequency         = vidioc_s_frequency,
  	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
  #ifdef CONFIG_VIDEO_ADV_DEBUG
  	.vidioc_g_chip_info         = vidioc_g_chip_info,
  	.vidioc_g_register          = vidioc_g_register,
  	.vidioc_s_register          = vidioc_s_register,
  #endif
  };
  
  static const struct video_device em28xx_video_template = {
  	.fops		= &em28xx_v4l_fops,
  	.ioctl_ops	= &video_ioctl_ops,
  	.release	= video_device_release_empty,
  	.tvnorms	= V4L2_STD_ALL,
  };
  
  static const struct v4l2_file_operations radio_fops = {
  	.owner         = THIS_MODULE,
  	.open          = em28xx_v4l2_open,
  	.release       = em28xx_v4l2_close,
  	.unlocked_ioctl = video_ioctl2,
  };
  
  static const struct v4l2_ioctl_ops radio_ioctl_ops = {
  	.vidioc_querycap      = vidioc_querycap,
  	.vidioc_g_tuner       = radio_g_tuner,
  	.vidioc_s_tuner       = radio_s_tuner,
  	.vidioc_g_frequency   = vidioc_g_frequency,
  	.vidioc_s_frequency   = vidioc_s_frequency,
  	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
  #ifdef CONFIG_VIDEO_ADV_DEBUG
  	.vidioc_g_chip_info   = vidioc_g_chip_info,
  	.vidioc_g_register    = vidioc_g_register,
  	.vidioc_s_register    = vidioc_s_register,
  #endif
  };
  
  static struct video_device em28xx_radio_template = {
  	.fops		= &radio_fops,
  	.ioctl_ops	= &radio_ioctl_ops,
  	.release	= video_device_release_empty,
  };
  
  /* I2C possible address to saa7115, tvp5150, msp3400, tvaudio */
  static unsigned short saa711x_addrs[] = {
  	0x4a >> 1, 0x48 >> 1,   /* SAA7111, SAA7111A and SAA7113 */
  	0x42 >> 1, 0x40 >> 1,   /* SAA7114, SAA7115 and SAA7118 */
  	I2C_CLIENT_END };
  
  static unsigned short tvp5150_addrs[] = {
  	0xb8 >> 1,
  	0xba >> 1,
  	I2C_CLIENT_END
  };
  
  static unsigned short msp3400_addrs[] = {
  	0x80 >> 1,
  	0x88 >> 1,
  	I2C_CLIENT_END
  };
  
  /******************************** usb interface ******************************/
  
  static void em28xx_vdev_init(struct em28xx *dev,
  			     struct video_device *vfd,
  			     const struct video_device *template,
  			     const char *type_name)
  {
  	*vfd		= *template;
  	vfd->v4l2_dev	= &dev->v4l2->v4l2_dev;
  	vfd->lock	= &dev->lock;
  	if (dev->board.is_webcam)
  		vfd->tvnorms = 0;
  
  	snprintf(vfd->name, sizeof(vfd->name), "%s %s",
  		 dev->name, type_name);
  
  	video_set_drvdata(vfd, dev);
  }
  
  static void em28xx_tuner_setup(struct em28xx *dev, unsigned short tuner_addr)
  {
  	struct em28xx_v4l2      *v4l2 = dev->v4l2;
  	struct v4l2_device      *v4l2_dev = &v4l2->v4l2_dev;
  	struct tuner_setup      tun_setup;
  	struct v4l2_frequency   f;
  
  	memset(&tun_setup, 0, sizeof(tun_setup));
  
  	tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
  	tun_setup.tuner_callback = em28xx_tuner_callback;
  
  	if (dev->board.radio.type) {
  		tun_setup.type = dev->board.radio.type;
  		tun_setup.addr = dev->board.radio_addr;
  
  		v4l2_device_call_all(v4l2_dev,
  				     0, tuner, s_type_addr, &tun_setup);
  	}
  
  	if ((dev->tuner_type != TUNER_ABSENT) && (dev->tuner_type)) {
  		tun_setup.type   = dev->tuner_type;
  		tun_setup.addr   = tuner_addr;
  
  		v4l2_device_call_all(v4l2_dev,
  				     0, tuner, s_type_addr, &tun_setup);
  	}
  
  	if (dev->board.tda9887_conf) {
  		struct v4l2_priv_tun_config tda9887_cfg;
  
  		tda9887_cfg.tuner = TUNER_TDA9887;
  		tda9887_cfg.priv = &dev->board.tda9887_conf;
  
  		v4l2_device_call_all(v4l2_dev,
  				     0, tuner, s_config, &tda9887_cfg);
  	}
  
  	if (dev->tuner_type == TUNER_XC2028) {
  		struct v4l2_priv_tun_config  xc2028_cfg;
  		struct xc2028_ctrl           ctl;
  
  		memset(&xc2028_cfg, 0, sizeof(xc2028_cfg));
  		memset(&ctl, 0, sizeof(ctl));
  
  		em28xx_setup_xc3028(dev, &ctl);
  
  		xc2028_cfg.tuner = TUNER_XC2028;
  		xc2028_cfg.priv  = &ctl;
  
  		v4l2_device_call_all(v4l2_dev, 0, tuner, s_config, &xc2028_cfg);
  	}
  
  	/* configure tuner */
  	f.tuner = 0;
  	f.type = V4L2_TUNER_ANALOG_TV;
  	f.frequency = 9076;     /* just a magic number */
  	v4l2->frequency = f.frequency;
  	v4l2_device_call_all(v4l2_dev, 0, tuner, s_frequency, &f);
  }
  
  static int em28xx_v4l2_init(struct em28xx *dev)
  {
  	u8 val;
  	int ret;
  	unsigned int maxw;
  	struct v4l2_ctrl_handler *hdl;
  	struct em28xx_v4l2 *v4l2;
  
  	if (dev->is_audio_only) {
  		/* Shouldn't initialize IR for this interface */
  		return 0;
  	}
  
  	if (!dev->has_video) {
  		/* This device does not support the v4l2 extension */
  		return 0;
  	}
  
  	em28xx_info("Registering V4L2 extension\n");
  
  	mutex_lock(&dev->lock);
  
  	v4l2 = kzalloc(sizeof(struct em28xx_v4l2), GFP_KERNEL);
  	if (v4l2 == NULL) {
  		em28xx_info("em28xx_v4l: memory allocation failed\n");
  		mutex_unlock(&dev->lock);
  		return -ENOMEM;
  	}
  	kref_init(&v4l2->ref);
  	v4l2->dev = dev;
  	dev->v4l2 = v4l2;
  
  #ifdef CONFIG_MEDIA_CONTROLLER
  	v4l2->v4l2_dev.mdev = dev->media_dev;
  #endif
  	ret = v4l2_device_register(&dev->udev->dev, &v4l2->v4l2_dev);
  	if (ret < 0) {
  		em28xx_errdev("Call to v4l2_device_register() failed!\n");
  		goto err;
  	}
  
  	hdl = &v4l2->ctrl_handler;
  	v4l2_ctrl_handler_init(hdl, 8);
  	v4l2->v4l2_dev.ctrl_handler = hdl;
  
  	if (dev->board.is_webcam)
  		v4l2->progressive = true;
  
  	/*
  	 * Default format, used for tvp5150 or saa711x output formats
  	 */
  	v4l2->vinmode = 0x10;
  	v4l2->vinctl  = EM28XX_VINCTRL_INTERLACED |
  			EM28XX_VINCTRL_CCIR656_ENABLE;
  
  	/* request some modules */
  
  	if (dev->board.has_msp34xx)
  		v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  				    &dev->i2c_adap[dev->def_i2c_bus],
  				    "msp3400", 0, msp3400_addrs);
  
  	if (dev->board.decoder == EM28XX_SAA711X)
  		v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  				    &dev->i2c_adap[dev->def_i2c_bus],
  				    "saa7115_auto", 0, saa711x_addrs);
  
  	if (dev->board.decoder == EM28XX_TVP5150)
  		v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  				    &dev->i2c_adap[dev->def_i2c_bus],
  				    "tvp5150", 0, tvp5150_addrs);
  
  	if (dev->board.adecoder == EM28XX_TVAUDIO)
  		v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  				    &dev->i2c_adap[dev->def_i2c_bus],
  				    "tvaudio", dev->board.tvaudio_addr, NULL);
  
  	/* Initialize tuner and camera */
  
  	if (dev->board.tuner_type != TUNER_ABSENT) {
  		unsigned short tuner_addr = dev->board.tuner_addr;
  		int has_demod = (dev->board.tda9887_conf & TDA9887_PRESENT);
  
  		if (dev->board.radio.type)
  			v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  					    &dev->i2c_adap[dev->def_i2c_bus],
  					    "tuner", dev->board.radio_addr,
  					    NULL);
  
  		if (has_demod)
  			v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  					    &dev->i2c_adap[dev->def_i2c_bus],
  					    "tuner", 0,
  					    v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
  		if (tuner_addr == 0) {
  			enum v4l2_i2c_tuner_type type =
  				has_demod ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;
  			struct v4l2_subdev *sd;
  
  			sd = v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  						 &dev->i2c_adap[dev->def_i2c_bus],
  						 "tuner", 0,
  						 v4l2_i2c_tuner_addrs(type));
  
  			if (sd)
  				tuner_addr = v4l2_i2c_subdev_addr(sd);
  		} else {
  			v4l2_i2c_new_subdev(&v4l2->v4l2_dev,
  					    &dev->i2c_adap[dev->def_i2c_bus],
  					    "tuner", tuner_addr, NULL);
  		}
  
  		em28xx_tuner_setup(dev, tuner_addr);
  	}
  
  	if (dev->em28xx_sensor != EM28XX_NOSENSOR)
  		em28xx_init_camera(dev);
  
  	/* Configure audio */
  	ret = em28xx_audio_setup(dev);
  	if (ret < 0) {
  		em28xx_errdev("%s: Error while setting audio - error [%d]!\n",
  			      __func__, ret);
  		goto unregister_dev;
  	}
  	if (dev->audio_mode.ac97 != EM28XX_NO_AC97) {
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_AUDIO_VOLUME, 0, 0x1f, 1, 0x1f);
  	} else {
  		/* install the em28xx notify callback */
  		v4l2_ctrl_notify(v4l2_ctrl_find(hdl, V4L2_CID_AUDIO_MUTE),
  				 em28xx_ctrl_notify, dev);
  		v4l2_ctrl_notify(v4l2_ctrl_find(hdl, V4L2_CID_AUDIO_VOLUME),
  				 em28xx_ctrl_notify, dev);
  	}
  
  	/* wake i2c devices */
  	em28xx_wake_i2c(dev);
  
  	/* init video dma queues */
  	INIT_LIST_HEAD(&dev->vidq.active);
  	INIT_LIST_HEAD(&dev->vbiq.active);
  
  	if (dev->board.has_msp34xx) {
  		/* Send a reset to other chips via gpio */
  		ret = em28xx_write_reg(dev, EM2820_R08_GPIO_CTRL, 0xf7);
  		if (ret < 0) {
  			em28xx_errdev("%s: em28xx_write_reg - msp34xx(1) failed! error [%d]\n",
  				      __func__, ret);
  			goto unregister_dev;
  		}
  		msleep(3);
  
  		ret = em28xx_write_reg(dev, EM2820_R08_GPIO_CTRL, 0xff);
  		if (ret < 0) {
  			em28xx_errdev("%s: em28xx_write_reg - msp34xx(2) failed! error [%d]\n",
  				      __func__, ret);
  			goto unregister_dev;
  		}
  		msleep(3);
  	}
  
  	/* set default norm */
  	v4l2->norm = V4L2_STD_PAL;
  	v4l2_device_call_all(&v4l2->v4l2_dev, 0, video, s_std, v4l2->norm);
  	v4l2->interlaced_fieldmode = EM28XX_INTERLACED_DEFAULT;
  
  	/* Analog specific initialization */
  	v4l2->format = &format[0];
  
  	maxw = norm_maxw(dev);
  	/* MaxPacketSize for em2800 is too small to capture at full resolution
  	 * use half of maxw as the scaler can only scale to 50% */
  	if (dev->board.is_em2800)
  		maxw /= 2;
  
  	em28xx_set_video_format(dev, format[0].fourcc,
  				maxw, norm_maxh(dev));
  
  	video_mux(dev, 0);
  
  	/* Audio defaults */
  	dev->mute = 1;
  	dev->volume = 0x1f;
  
  /*	em28xx_write_reg(dev, EM28XX_R0E_AUDIOSRC, 0xc0); audio register */
  	val = (u8)em28xx_read_reg(dev, EM28XX_R0F_XCLK);
  	em28xx_write_reg(dev, EM28XX_R0F_XCLK,
  			 (EM28XX_XCLK_AUDIO_UNMUTE | val));
  
  	em28xx_set_outfmt(dev);
  
  	/* Add image controls */
  	/* NOTE: at this point, the subdevices are already registered, so bridge
  	 * controls are only added/enabled when no subdevice provides them */
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_CONTRAST))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_CONTRAST,
  				  0, 0x1f, 1, CONTRAST_DEFAULT);
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_BRIGHTNESS))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_BRIGHTNESS,
  				  -0x80, 0x7f, 1, BRIGHTNESS_DEFAULT);
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_SATURATION))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_SATURATION,
  				  0, 0x1f, 1, SATURATION_DEFAULT);
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_BLUE_BALANCE))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_BLUE_BALANCE,
  				  -0x30, 0x30, 1, BLUE_BALANCE_DEFAULT);
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_RED_BALANCE))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_RED_BALANCE,
  				  -0x30, 0x30, 1, RED_BALANCE_DEFAULT);
  	if (NULL == v4l2_ctrl_find(hdl, V4L2_CID_SHARPNESS))
  		v4l2_ctrl_new_std(hdl, &em28xx_ctrl_ops,
  				  V4L2_CID_SHARPNESS,
  				  0, 0x0f, 1, SHARPNESS_DEFAULT);
  
  	/* Reset image controls */
  	em28xx_colorlevels_set_default(dev);
  	v4l2_ctrl_handler_setup(hdl);
  	ret = hdl->error;
  	if (ret)
  		goto unregister_dev;
  
  	/* allocate and fill video video_device struct */
  	em28xx_vdev_init(dev, &v4l2->vdev, &em28xx_video_template, "video");
  	mutex_init(&v4l2->vb_queue_lock);
  	mutex_init(&v4l2->vb_vbi_queue_lock);
  	v4l2->vdev.queue = &v4l2->vb_vidq;
  	v4l2->vdev.queue->lock = &v4l2->vb_queue_lock;
  
  	/* disable inapplicable ioctls */
  	if (dev->board.is_webcam) {
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_QUERYSTD);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_G_STD);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_S_STD);
  	} else {
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_S_PARM);
  	}
  	if (dev->tuner_type == TUNER_ABSENT) {
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_G_TUNER);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_S_TUNER);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_G_FREQUENCY);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_S_FREQUENCY);
  	}
  	if (dev->int_audio_type == EM28XX_INT_AUDIO_NONE) {
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_G_AUDIO);
  		v4l2_disable_ioctl(&v4l2->vdev, VIDIOC_S_AUDIO);
  	}
  
  	/* register v4l2 video video_device */
  	ret = video_register_device(&v4l2->vdev, VFL_TYPE_GRABBER,
  				    video_nr[dev->devno]);
  	if (ret) {
  		em28xx_errdev("unable to register video device (error=%i).\n",
  			      ret);
  		goto unregister_dev;
  	}
  
  	/* Allocate and fill vbi video_device struct */
  	if (em28xx_vbi_supported(dev) == 1) {
  		em28xx_vdev_init(dev, &v4l2->vbi_dev, &em28xx_video_template,
  				"vbi");
  
  		v4l2->vbi_dev.queue = &v4l2->vb_vbiq;
  		v4l2->vbi_dev.queue->lock = &v4l2->vb_vbi_queue_lock;
  
  		/* disable inapplicable ioctls */
  		v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_S_PARM);
  		if (dev->tuner_type == TUNER_ABSENT) {
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_G_TUNER);
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_S_TUNER);
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_G_FREQUENCY);
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_S_FREQUENCY);
  		}
  		if (dev->int_audio_type == EM28XX_INT_AUDIO_NONE) {
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_G_AUDIO);
  			v4l2_disable_ioctl(&v4l2->vbi_dev, VIDIOC_S_AUDIO);
  		}
  
  		/* register v4l2 vbi video_device */
  		ret = video_register_device(&v4l2->vbi_dev, VFL_TYPE_VBI,
  					    vbi_nr[dev->devno]);
  		if (ret < 0) {
  			em28xx_errdev("unable to register vbi device\n");
  			goto unregister_dev;
  		}
  	}
  
  	if (em28xx_boards[dev->model].radio.type == EM28XX_RADIO) {
  		em28xx_vdev_init(dev, &v4l2->radio_dev, &em28xx_radio_template,
  				   "radio");
  		ret = video_register_device(&v4l2->radio_dev, VFL_TYPE_RADIO,
  					    radio_nr[dev->devno]);
  		if (ret < 0) {
  			em28xx_errdev("can't register radio device\n");
  			goto unregister_dev;
  		}
  		em28xx_info("Registered radio device as %s\n",
  			    video_device_node_name(&v4l2->radio_dev));
  	}
  
  	/* Init entities at the Media Controller */
  	em28xx_v4l2_create_entities(dev);
  
  #ifdef CONFIG_MEDIA_CONTROLLER
  	ret = v4l2_mc_create_media_graph(dev->media_dev);
  	if (ret) {
  		em28xx_errdev("failed to create media graph\n");
  		em28xx_v4l2_media_release(dev);
  		goto unregister_dev;
  	}
  #endif
  
  	em28xx_info("V4L2 video device registered as %s\n",
  		    video_device_node_name(&v4l2->vdev));
  
  	if (video_is_registered(&v4l2->vbi_dev))
  		em28xx_info("V4L2 VBI device registered as %s\n",
  			    video_device_node_name(&v4l2->vbi_dev));
  
  	/* Save some power by putting tuner to sleep */
  	v4l2_device_call_all(&v4l2->v4l2_dev, 0, core, s_power, 0);
  
  	/* initialize videobuf2 stuff */
  	em28xx_vb2_setup(dev);
  
  	em28xx_info("V4L2 extension successfully initialized\n");
  
  	kref_get(&dev->ref);
  
  	mutex_unlock(&dev->lock);
  	return 0;
  
  unregister_dev:
  	if (video_is_registered(&v4l2->radio_dev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->radio_dev));
  		video_unregister_device(&v4l2->radio_dev);
  	}
  	if (video_is_registered(&v4l2->vbi_dev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->vbi_dev));
  		video_unregister_device(&v4l2->vbi_dev);
  	}
  	if (video_is_registered(&v4l2->vdev)) {
  		em28xx_info("V4L2 device %s deregistered\n",
  			    video_device_node_name(&v4l2->vdev));
  		video_unregister_device(&v4l2->vdev);
  	}
  
  	v4l2_ctrl_handler_free(&v4l2->ctrl_handler);
  	v4l2_device_unregister(&v4l2->v4l2_dev);
  err:
  	dev->v4l2 = NULL;
  	kref_put(&v4l2->ref, em28xx_free_v4l2);
  	mutex_unlock(&dev->lock);
  	return ret;
  }
  
  static struct em28xx_ops v4l2_ops = {
  	.id   = EM28XX_V4L2,
  	.name = "Em28xx v4l2 Extension",
  	.init = em28xx_v4l2_init,
  	.fini = em28xx_v4l2_fini,
  	.suspend = em28xx_v4l2_suspend,
  	.resume = em28xx_v4l2_resume,
  };
  
  static int __init em28xx_video_register(void)
  {
  	return em28xx_register_extension(&v4l2_ops);
  }
  
  static void __exit em28xx_video_unregister(void)
  {
  	em28xx_unregister_extension(&v4l2_ops);
  }
  
  module_init(em28xx_video_register);
  module_exit(em28xx_video_unregister);
  