/*
   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>

	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 <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-chip-ident.h>
#include <media/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>"

#define DRIVER_DESC         "Empia em28xx based USB video device driver"

#define EM28XX_VERSION "0.1.3"

#define em28xx_videodbg(fmt, arg...) do {\
	if (video_debug) \
		printk(KERN_INFO "%s %s :"fmt, \
			 dev->name, __func__ , ##arg); } while (0)

static unsigned int isoc_debug;
module_param(isoc_debug, int, 0644);
MODULE_PARM_DESC(isoc_debug, "enable debug messages [isoc transfers]");

#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);
MODULE_LICENSE("GPL");
MODULE_VERSION(EM28XX_VERSION);

static unsigned int video_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = UNSET };
static unsigned int vbi_nr[]   = {[0 ... (EM28XX_MAXBOARDS - 1)] = UNSET };
static unsigned int radio_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = UNSET };

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,
	},
};

/* supported controls */
/* Common to all boards */
static struct v4l2_queryctrl ac97_qctrl[] = {
	{
		.id = V4L2_CID_AUDIO_VOLUME,
		.type = V4L2_CTRL_TYPE_INTEGER,
		.name = "Volume",
		.minimum = 0x0,
		.maximum = 0x1f,
		.step = 0x1,
		.default_value = 0x1f,
		.flags = V4L2_CTRL_FLAG_SLIDER,
	}, {
		.id = V4L2_CID_AUDIO_MUTE,
		.type = V4L2_CTRL_TYPE_BOOLEAN,
		.name = "Mute",
		.minimum = 0,
		.maximum = 1,
		.step = 1,
		.default_value = 1,
		.flags = 0,
	}
};

/* ------------------------------------------------------------------
	DMA and thread functions
   ------------------------------------------------------------------*/

/*
 * Announces that a buffer were filled and request the next
 */
static inline void buffer_filled(struct em28xx *dev,
				  struct em28xx_dmaqueue *dma_q,
				  struct em28xx_buffer *buf)
{
	/* Advice that buffer was filled */
	em28xx_isocdbg("[%p/%d] wakeup\n", buf, buf->vb.i);
	buf->vb.state = VIDEOBUF_DONE;
	buf->vb.field_count++;
	do_gettimeofday(&buf->vb.ts);

	dev->isoc_ctl.vid_buf = NULL;

	list_del(&buf->vb.queue);
	wake_up(&buf->vb.done);
}

static inline void vbi_buffer_filled(struct em28xx *dev,
				     struct em28xx_dmaqueue *dma_q,
				     struct em28xx_buffer *buf)
{
	/* Advice that buffer was filled */
	em28xx_isocdbg("[%p/%d] wakeup\n", buf, buf->vb.i);

	buf->vb.state = VIDEOBUF_DONE;
	buf->vb.field_count++;
	do_gettimeofday(&buf->vb.ts);

	dev->isoc_ctl.vbi_buf = NULL;

	list_del(&buf->vb.queue);
	wake_up(&buf->vb.done);
}

/*
 * Identify the buffer header type and properly handles
 */
static void em28xx_copy_video(struct em28xx *dev,
			      struct em28xx_dmaqueue  *dma_q,
			      struct em28xx_buffer *buf,
			      unsigned char *p,
			      unsigned char *outp, unsigned long len)
{
	void *fieldstart, *startwrite, *startread;
	int  linesdone, currlinedone, offset, lencopy, remain;
	int bytesperline = dev->width << 1;

	if (dma_q->pos + len > buf->vb.size)
		len = buf->vb.size - dma_q->pos;

	startread = p;
	remain = len;

	if (dev->progressive)
		fieldstart = outp;
	else {
		/* Interlaces two half frames */
		if (buf->top_field)
			fieldstart = outp;
		else
			fieldstart = outp + bytesperline;
	}

	linesdone = dma_q->pos / bytesperline;
	currlinedone = dma_q->pos % bytesperline;

	if (dev->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 *)outp + buf->vb.size) {
		em28xx_isocdbg("Overflow of %zi bytes past buffer end (1)\n",
			       ((char *)startwrite + lencopy) -
			       ((char *)outp + buf->vb.size));
		remain = (char *)outp + buf->vb.size - (char *)startwrite;
		lencopy = remain;
	}
	if (lencopy <= 0)
		return;
	memcpy(startwrite, startread, lencopy);

	remain -= lencopy;

	while (remain > 0) {
		startwrite += lencopy + bytesperline;
		startread += lencopy;
		if (bytesperline > remain)
			lencopy = remain;
		else
			lencopy = bytesperline;

		if ((char *)startwrite + lencopy > (char *)outp +
		    buf->vb.size) {
			em28xx_isocdbg("Overflow of %zi bytes past buffer end"
				       "(2)\n",
				       ((char *)startwrite + lencopy) -
				       ((char *)outp + buf->vb.size));
			lencopy = remain = (char *)outp + buf->vb.size -
					   (char *)startwrite;
		}
		if (lencopy <= 0)
			break;

		memcpy(startwrite, startread, lencopy);

		remain -= lencopy;
	}

	dma_q->pos += len;
}

static void em28xx_copy_vbi(struct em28xx *dev,
			      struct em28xx_dmaqueue  *dma_q,
			      struct em28xx_buffer *buf,
			      unsigned char *p,
			      unsigned char *outp, unsigned long len)
{
	void *startwrite, *startread;
	int  offset;
	int bytesperline;

	if (dev == NULL) {
		em28xx_isocdbg("dev is null\n");
		return;
	}
	bytesperline = dev->vbi_width;

	if (dma_q == NULL) {
		em28xx_isocdbg("dma_q is null\n");
		return;
	}
	if (buf == NULL) {
		return;
	}
	if (p == NULL) {
		em28xx_isocdbg("p is null\n");
		return;
	}
	if (outp == NULL) {
		em28xx_isocdbg("outp is null\n");
		return;
	}

	if (dma_q->pos + len > buf->vb.size)
		len = buf->vb.size - dma_q->pos;

	startread = p;

	startwrite = outp + dma_q->pos;
	offset = dma_q->pos;

	/* Make sure the bottom field populates the second half of the frame */
	if (buf->top_field == 0) {
		startwrite += bytesperline * dev->vbi_height;
		offset += bytesperline * dev->vbi_height;
	}

	memcpy(startwrite, startread, len);
	dma_q->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);
	}
}

/*
 * video-buf generic routine to get the next available buffer
 */
static inline void get_next_buf(struct em28xx_dmaqueue *dma_q,
					  struct em28xx_buffer **buf)
{
	struct em28xx *dev = container_of(dma_q, struct em28xx, vidq);
	char *outp;

	if (list_empty(&dma_q->active)) {
		em28xx_isocdbg("No active queue to serve\n");
		dev->isoc_ctl.vid_buf = NULL;
		*buf = NULL;
		return;
	}

	/* Get the next buffer */
	*buf = list_entry(dma_q->active.next, struct em28xx_buffer, vb.queue);

	/* Cleans up buffer - Useful for testing for frame/URB loss */
	outp = videobuf_to_vmalloc(&(*buf)->vb);
	memset(outp, 0, (*buf)->vb.size);

	dev->isoc_ctl.vid_buf = *buf;

	return;
}

/*
 * video-buf generic routine to get the next available VBI buffer
 */
static inline void vbi_get_next_buf(struct em28xx_dmaqueue *dma_q,
				    struct em28xx_buffer **buf)
{
	struct em28xx *dev = container_of(dma_q, struct em28xx, vbiq);
	char *outp;

	if (list_empty(&dma_q->active)) {
		em28xx_isocdbg("No active queue to serve\n");
		dev->isoc_ctl.vbi_buf = NULL;
		*buf = NULL;
		return;
	}

	/* Get the next buffer */
	*buf = list_entry(dma_q->active.next, struct em28xx_buffer, vb.queue);
	/* Cleans up buffer - Useful for testing for frame/URB loss */
	outp = videobuf_to_vmalloc(&(*buf)->vb);
	memset(outp, 0x00, (*buf)->vb.size);

	dev->isoc_ctl.vbi_buf = *buf;

	return;
}

/*
 * Controls the isoc copy of each urb packet
 */
static inline int em28xx_isoc_copy(struct em28xx *dev, struct urb *urb)
{
	struct em28xx_buffer    *buf;
	struct em28xx_dmaqueue  *dma_q = &dev->vidq;
	unsigned char *outp = NULL;
	int i, len = 0, rc = 1;
	unsigned char *p;

	if (!dev)
		return 0;

	if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
		return 0;

	if (urb->status < 0) {
		print_err_status(dev, -1, urb->status);
		if (urb->status == -ENOENT)
			return 0;
	}

	buf = dev->isoc_ctl.vid_buf;
	if (buf != NULL)
		outp = videobuf_to_vmalloc(&buf->vb);

	for (i = 0; i < urb->number_of_packets; i++) {
		int status = urb->iso_frame_desc[i].status;

		if (status < 0) {
			print_err_status(dev, i, status);
			if (urb->iso_frame_desc[i].status != -EPROTO)
				continue;
		}

		len = urb->iso_frame_desc[i].actual_length - 4;

		if (urb->iso_frame_desc[i].actual_length <= 0) {
			/* em28xx_isocdbg("packet %d is empty",i); - spammy */
			continue;
		}
		if (urb->iso_frame_desc[i].actual_length >
						dev->max_pkt_size) {
			em28xx_isocdbg("packet bigger than packet size");
			continue;
		}

		p = urb->transfer_buffer + urb->iso_frame_desc[i].offset;

		/* FIXME: incomplete buffer checks where removed to make
		   logic simpler. Impacts of those changes should be evaluated
		 */
		if (p[0] == 0x33 && p[1] == 0x95 && p[2] == 0x00) {
			em28xx_isocdbg("VBI HEADER!!!\n");
			/* FIXME: Should add vbi copy */
			continue;
		}
		if (p[0] == 0x22 && p[1] == 0x5a) {
			em28xx_isocdbg("Video frame %d, length=%i, %s\n", p[2],
				       len, (p[2] & 1) ? "odd" : "even");

			if (dev->progressive || !(p[2] & 1)) {
				if (buf != NULL)
					buffer_filled(dev, dma_q, buf);
				get_next_buf(dma_q, &buf);
				if (buf == NULL)
					outp = NULL;
				else
					outp = videobuf_to_vmalloc(&buf->vb);
			}

			if (buf != NULL) {
				if (p[2] & 1)
					buf->top_field = 0;
				else
					buf->top_field = 1;
			}

			dma_q->pos = 0;
		}
		if (buf != NULL) {
			if (p[0] != 0x88 && p[0] != 0x22) {
				em28xx_isocdbg("frame is not complete\n");
				len += 4;
			} else {
				p += 4;
			}
			em28xx_copy_video(dev, dma_q, buf, p, outp, len);
		}
	}
	return rc;
}

/* Version of isoc handler that takes into account a mixture of video and
   VBI data */
static inline int em28xx_isoc_copy_vbi(struct em28xx *dev, struct urb *urb)
{
	struct em28xx_buffer    *buf, *vbi_buf;
	struct em28xx_dmaqueue  *dma_q = &dev->vidq;
	struct em28xx_dmaqueue  *vbi_dma_q = &dev->vbiq;
	unsigned char *outp = NULL;
	unsigned char *vbioutp = NULL;
	int i, len = 0, rc = 1;
	unsigned char *p;
	int vbi_size;

	if (!dev)
		return 0;

	if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
		return 0;

	if (urb->status < 0) {
		print_err_status(dev, -1, urb->status);
		if (urb->status == -ENOENT)
			return 0;
	}

	buf = dev->isoc_ctl.vid_buf;
	if (buf != NULL)
		outp = videobuf_to_vmalloc(&buf->vb);

	vbi_buf = dev->isoc_ctl.vbi_buf;
	if (vbi_buf != NULL)
		vbioutp = videobuf_to_vmalloc(&vbi_buf->vb);

	for (i = 0; i < urb->number_of_packets; i++) {
		int status = urb->iso_frame_desc[i].status;

		if (status < 0) {
			print_err_status(dev, i, status);
			if (urb->iso_frame_desc[i].status != -EPROTO)
				continue;
		}

		len = urb->iso_frame_desc[i].actual_length;
		if (urb->iso_frame_desc[i].actual_length <= 0) {
			/* em28xx_isocdbg("packet %d is empty",i); - spammy */
			continue;
		}
		if (urb->iso_frame_desc[i].actual_length >
						dev->max_pkt_size) {
			em28xx_isocdbg("packet bigger than packet size");
			continue;
		}

		p = urb->transfer_buffer + urb->iso_frame_desc[i].offset;

		/* capture type 0 = vbi start
		   capture type 1 = video start
		   capture type 2 = video in progress */
		if (p[0] == 0x33 && p[1] == 0x95) {
			dev->capture_type = 0;
			dev->vbi_read = 0;
			em28xx_isocdbg("VBI START HEADER!!!\n");
			dev->cur_field = p[2];
			p += 4;
			len -= 4;
		} else if (p[0] == 0x88 && p[1] == 0x88 &&
			   p[2] == 0x88 && p[3] == 0x88) {
			/* continuation */
			p += 4;
			len -= 4;
		} else if (p[0] == 0x22 && p[1] == 0x5a) {
			/* start video */
			p += 4;
			len -= 4;
		}

		vbi_size = dev->vbi_width * dev->vbi_height;

		if (dev->capture_type == 0) {
			if (dev->vbi_read >= vbi_size) {
				/* We've already read all the VBI data, so
				   treat the rest as video */
				em28xx_isocdbg("dev->vbi_read > vbi_size\n");
			} else if ((dev->vbi_read + len) < vbi_size) {
				/* This entire frame is VBI data */
				if (dev->vbi_read == 0 &&
				    (!(dev->cur_field & 1))) {
					/* Brand new frame */
					if (vbi_buf != NULL)
						vbi_buffer_filled(dev,
								  vbi_dma_q,
								  vbi_buf);
					vbi_get_next_buf(vbi_dma_q, &vbi_buf);
					if (vbi_buf == NULL)
						vbioutp = NULL;
					else
						vbioutp = videobuf_to_vmalloc(
							&vbi_buf->vb);
				}

				if (dev->vbi_read == 0) {
					vbi_dma_q->pos = 0;
					if (vbi_buf != NULL) {
						if (dev->cur_field & 1)
							vbi_buf->top_field = 0;
						else
							vbi_buf->top_field = 1;
					}
				}

				dev->vbi_read += len;
				em28xx_copy_vbi(dev, vbi_dma_q, vbi_buf, p,
						vbioutp, len);
			} else {
				/* Some of this frame is VBI data and some is
				   video data */
				int vbi_data_len = vbi_size - dev->vbi_read;
				dev->vbi_read += vbi_data_len;
				em28xx_copy_vbi(dev, vbi_dma_q, vbi_buf, p,
						vbioutp, vbi_data_len);
				dev->capture_type = 1;
				p += vbi_data_len;
				len -= vbi_data_len;
			}
		}

		if (dev->capture_type == 1) {
			dev->capture_type = 2;
			if (dev->progressive || !(dev->cur_field & 1)) {
				if (buf != NULL)
					buffer_filled(dev, dma_q, buf);
				get_next_buf(dma_q, &buf);
				if (buf == NULL)
					outp = NULL;
				else
					outp = videobuf_to_vmalloc(&buf->vb);
			}
			if (buf != NULL) {
				if (dev->cur_field & 1)
					buf->top_field = 0;
				else
					buf->top_field = 1;
			}

			dma_q->pos = 0;
		}

		if (buf != NULL && dev->capture_type == 2) {
			if (len >= 4 && p[0] == 0x88 && p[1] == 0x88 &&
			    p[2] == 0x88 && p[3] == 0x88) {
				p += 4;
				len -= 4;
			}
			if (len >= 4 && p[0] == 0x22 && p[1] == 0x5a) {
				em28xx_isocdbg("Video frame %d, len=%i, %s\n",
					       p[2], len, (p[2] & 1) ?
					       "odd" : "even");
				p += 4;
				len -= 4;
			}

			if (len > 0)
				em28xx_copy_video(dev, dma_q, buf, p, outp,
						  len);
		}
	}
	return rc;
}


/* ------------------------------------------------------------------
	Videobuf operations
   ------------------------------------------------------------------*/

static int
buffer_setup(struct videobuf_queue *vq, unsigned int *count, unsigned int *size)
{
	struct em28xx_fh *fh = vq->priv_data;
	struct em28xx        *dev = fh->dev;
	struct v4l2_frequency f;

	*size = (fh->dev->width * fh->dev->height * dev->format->depth + 7)
		>> 3;

	if (0 == *count)
		*count = EM28XX_DEF_BUF;

	if (*count < EM28XX_MIN_BUF)
		*count = EM28XX_MIN_BUF;

	/* Ask tuner to go to analog or radio mode */
	memset(&f, 0, sizeof(f));
	f.frequency = dev->ctl_freq;
	f.type = fh->radio ? V4L2_TUNER_RADIO : V4L2_TUNER_ANALOG_TV;

	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, s_frequency, &f);

	return 0;
}

/* This is called *without* dev->slock held; please keep it that way */
static void free_buffer(struct videobuf_queue *vq, struct em28xx_buffer *buf)
{
	struct em28xx_fh     *fh  = vq->priv_data;
	struct em28xx        *dev = fh->dev;
	unsigned long flags = 0;
	if (in_interrupt())
		BUG();

	/* We used to wait for the buffer to finish here, but this didn't work
	   because, as we were keeping the state as VIDEOBUF_QUEUED,
	   videobuf_queue_cancel marked it as finished for us.
	   (Also, it could wedge forever if the hardware was misconfigured.)

	   This should be safe; by the time we get here, the buffer isn't
	   queued anymore. If we ever start marking the buffers as
	   VIDEOBUF_ACTIVE, it won't be, though.
	*/
	spin_lock_irqsave(&dev->slock, flags);
	if (dev->isoc_ctl.vid_buf == buf)
		dev->isoc_ctl.vid_buf = NULL;
	spin_unlock_irqrestore(&dev->slock, flags);

	videobuf_vmalloc_free(&buf->vb);
	buf->vb.state = VIDEOBUF_NEEDS_INIT;
}

static int
buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
						enum v4l2_field field)
{
	struct em28xx_fh     *fh  = vq->priv_data;
	struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
	struct em28xx        *dev = fh->dev;
	int                  rc = 0, urb_init = 0;

	buf->vb.size = (fh->dev->width * fh->dev->height * dev->format->depth
			+ 7) >> 3;

	if (0 != buf->vb.baddr  &&  buf->vb.bsize < buf->vb.size)
		return -EINVAL;

	buf->vb.width  = dev->width;
	buf->vb.height = dev->height;
	buf->vb.field  = field;

	if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
		rc = videobuf_iolock(vq, &buf->vb, NULL);
		if (rc < 0)
			goto fail;
	}

	if (!dev->isoc_ctl.analog_bufs.num_bufs)
		urb_init = 1;

	if (urb_init) {
		if (em28xx_vbi_supported(dev) == 1)
			rc = em28xx_init_isoc(dev, EM28XX_ANALOG_MODE,
					      EM28XX_NUM_PACKETS,
					      EM28XX_NUM_BUFS,
					      dev->max_pkt_size,
					      em28xx_isoc_copy_vbi);
		else
			rc = em28xx_init_isoc(dev, EM28XX_ANALOG_MODE,
					      EM28XX_NUM_PACKETS,
					      EM28XX_NUM_BUFS,
					      dev->max_pkt_size,
					      em28xx_isoc_copy);
		if (rc < 0)
			goto fail;
	}

	buf->vb.state = VIDEOBUF_PREPARED;
	return 0;

fail:
	free_buffer(vq, buf);
	return rc;
}

static void
buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
{
	struct em28xx_buffer    *buf     = container_of(vb,
							struct em28xx_buffer,
							vb);
	struct em28xx_fh        *fh      = vq->priv_data;
	struct em28xx           *dev     = fh->dev;
	struct em28xx_dmaqueue  *vidq    = &dev->vidq;

	buf->vb.state = VIDEOBUF_QUEUED;
	list_add_tail(&buf->vb.queue, &vidq->active);

}

static void buffer_release(struct videobuf_queue *vq,
				struct videobuf_buffer *vb)
{
	struct em28xx_buffer   *buf  = container_of(vb,
						    struct em28xx_buffer,
						    vb);
	struct em28xx_fh       *fh   = vq->priv_data;
	struct em28xx          *dev  = (struct em28xx *)fh->dev;

	em28xx_isocdbg("em28xx: called buffer_release\n");

	free_buffer(vq, buf);
}

static struct videobuf_queue_ops em28xx_video_qops = {
	.buf_setup      = buffer_setup,
	.buf_prepare    = buffer_prepare,
	.buf_queue      = buffer_queue,
	.buf_release    = buffer_release,
};

/*********************  v4l2 interface  **************************************/

static void video_mux(struct em28xx *dev, int index)
{
	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(&dev->v4l2_dev, 0, video, s_routing,
			INPUT(index)->vmux, 0, 0);

	if (dev->board.has_msp34xx) {
		if (dev->i2s_speed) {
			v4l2_device_call_all(&dev->v4l2_dev, 0, audio,
				s_i2s_clock_freq, dev->i2s_speed);
		}
		/* Note: this is msp3400 specific */
		v4l2_device_call_all(&dev->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(&dev->v4l2_dev, 0, audio, s_routing,
			dev->ctl_ainput, dev->ctl_aoutput, 0);
	}

	em28xx_audio_analog_set(dev);
}

/* Usage lock check functions */
static int res_get(struct em28xx_fh *fh, unsigned int bit)
{
	struct em28xx    *dev = fh->dev;

	if (fh->resources & bit)
		/* have it already allocated */
		return 1;

	/* is it free? */
	if (dev->resources & bit) {
		/* no, someone else uses it */
		return 0;
	}
	/* it's free, grab it */
	fh->resources  |= bit;
	dev->resources |= bit;
	em28xx_videodbg("res: get %d\n", bit);
	return 1;
}

static int res_check(struct em28xx_fh *fh, unsigned int bit)
{
	return fh->resources & bit;
}

static int res_locked(struct em28xx *dev, unsigned int bit)
{
	return dev->resources & bit;
}

static void res_free(struct em28xx_fh *fh, unsigned int bits)
{
	struct em28xx    *dev = fh->dev;

	BUG_ON((fh->resources & bits) != bits);

	fh->resources  &= ~bits;
	dev->resources &= ~bits;
	em28xx_videodbg("res: put %d\n", bits);
}

static int get_ressource(struct em28xx_fh *fh)
{
	switch (fh->type) {
	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
		return EM28XX_RESOURCE_VIDEO;
	case V4L2_BUF_TYPE_VBI_CAPTURE:
		return EM28XX_RESOURCE_VBI;
	default:
		BUG();
		return 0;
	}
}

/*
 * ac97_queryctrl()
 * return the ac97 supported controls
 */
static int ac97_queryctrl(struct v4l2_queryctrl *qc)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(ac97_qctrl); i++) {
		if (qc->id && qc->id == ac97_qctrl[i].id) {
			memcpy(qc, &(ac97_qctrl[i]), sizeof(*qc));
			return 0;
		}
	}

	/* Control is not ac97 related */
	return 1;
}

/*
 * ac97_get_ctrl()
 * return the current values for ac97 mute and volume
 */
static int ac97_get_ctrl(struct em28xx *dev, struct v4l2_control *ctrl)
{
	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		ctrl->value = dev->mute;
		return 0;
	case V4L2_CID_AUDIO_VOLUME:
		ctrl->value = dev->volume;
		return 0;
	default:
		/* Control is not ac97 related */
		return 1;
	}
}

/*
 * ac97_set_ctrl()
 * set values for ac97 mute and volume
 */
static int ac97_set_ctrl(struct em28xx *dev, const struct v4l2_control *ctrl)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(ac97_qctrl); i++)
		if (ctrl->id == ac97_qctrl[i].id)
			goto handle;

	/* Announce that hasn't handle it */
	return 1;

handle:
	if (ctrl->value < ac97_qctrl[i].minimum ||
	    ctrl->value > ac97_qctrl[i].maximum)
		return -ERANGE;

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		dev->mute = ctrl->value;
		break;
	case V4L2_CID_AUDIO_VOLUME:
		dev->volume = ctrl->value;
		break;
	}

	return em28xx_audio_analog_set(dev);
}

static int check_dev(struct em28xx *dev)
{
	if (dev->state & DEV_DISCONNECTED) {
		em28xx_errdev("v4l2 ioctl: device not present\n");
		return -ENODEV;
	}

	if (dev->state & DEV_MISCONFIGURED) {
		em28xx_errdev("v4l2 ioctl: device is misconfigured; "
			      "close and open it again\n");
		return -EIO;
	}
	return 0;
}

static void get_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 >= 0x4000)
		*hscale = 0x3fff;

	*vscale = (((unsigned long)maxh) << 12) / height - 4096L;
	if (*vscale >= 0x4000)
		*vscale = 0x3fff;
}

/* ------------------------------------------------------------------
	IOCTL vidioc handling
   ------------------------------------------------------------------*/

static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
					struct v4l2_format *f)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	f->fmt.pix.width = dev->width;
	f->fmt.pix.height = dev->height;
	f->fmt.pix.pixelformat = dev->format->fourcc;
	f->fmt.pix.bytesperline = (dev->width * dev->format->depth + 7) >> 3;
	f->fmt.pix.sizeimage = f->fmt.pix.bytesperline  * dev->height;
	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;

	/* FIXME: TOP? NONE? BOTTOM? ALTENATE? */
	if (dev->progressive)
		f->fmt.pix.field = V4L2_FIELD_NONE;
	else
		f->fmt.pix.field = dev->interlaced ?
			   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_fh      *fh    = priv;
	struct em28xx         *dev   = fh->dev;
	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);
	}

	get_scale(dev, width, height, &hscale, &vscale);

	width = (((unsigned long)maxw) << 12) / (hscale + 4096L);
	height = (((unsigned long)maxh) << 12) / (vscale + 4096L);

	f->fmt.pix.width = width;
	f->fmt.pix.height = height;
	f->fmt.pix.pixelformat = fmt->fourcc;
	f->fmt.pix.bytesperline = (dev->width * fmt->depth + 7) >> 3;
	f->fmt.pix.sizeimage = f->fmt.pix.bytesperline * height;
	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
	if (dev->progressive)
		f->fmt.pix.field = V4L2_FIELD_NONE;
	else
		f->fmt.pix.field = dev->interlaced ?
			   V4L2_FIELD_INTERLACED : V4L2_FIELD_TOP;

	return 0;
}

static int em28xx_set_video_format(struct em28xx *dev, unsigned int fourcc,
				   unsigned width, unsigned height)
{
	struct em28xx_fmt     *fmt;

	fmt = format_by_fourcc(fourcc);
	if (!fmt)
		return -EINVAL;

	dev->format = fmt;
	dev->width  = width;
	dev->height = height;

	/* set new image size */
	get_scale(dev, dev->width, dev->height, &dev->hscale, &dev->vscale);

	em28xx_set_alternate(dev);
	em28xx_resolution_set(dev);

	return 0;
}

static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
			struct v4l2_format *f)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	vidioc_try_fmt_vid_cap(file, priv, f);

	if (videobuf_queue_is_busy(&fh->vb_vidq)) {
		em28xx_errdev("%s queue busy\n", __func__);
		return -EBUSY;
	}

	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_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	int                rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	*norm = dev->norm;

	return 0;
}

static int vidioc_querystd(struct file *file, void *priv, v4l2_std_id *norm)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	int                rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	v4l2_device_call_all(&dev->v4l2_dev, 0, video, querystd, norm);

	return 0;
}

static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id *norm)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	struct v4l2_format f;
	int                rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	dev->norm = *norm;

	/* Adjusts width/height, if needed */
	f.fmt.pix.width = dev->width;
	f.fmt.pix.height = dev->height;
	vidioc_try_fmt_vid_cap(file, priv, &f);

	/* set new image size */
	dev->width = f.fmt.pix.width;
	dev->height = f.fmt.pix.height;
	get_scale(dev, dev->width, dev->height, &dev->hscale, &dev->vscale);

	em28xx_resolution_set(dev);
	v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_std, dev->norm);

	return 0;
}

static int vidioc_g_parm(struct file *file, void *priv,
			 struct v4l2_streamparm *p)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	int rc = 0;

	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	if (dev->board.is_webcam)
		rc = v4l2_device_call_until_err(&dev->v4l2_dev, 0,
						video, g_parm, p);
	else
		v4l2_video_std_frame_period(dev->norm,
						 &p->parm.capture.timeperframe);

	return rc;
}

static int vidioc_s_parm(struct file *file, void *priv,
			 struct v4l2_streamparm *p)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;

	if (!dev->board.is_webcam)
		return -EINVAL;

	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	return v4l2_device_call_until_err(&dev->v4l2_dev, 0, video, s_parm, p);
}

static const char *iname[] = {
	[EM28XX_VMUX_COMPOSITE1] = "Composite1",
	[EM28XX_VMUX_COMPOSITE2] = "Composite2",
	[EM28XX_VMUX_COMPOSITE3] = "Composite3",
	[EM28XX_VMUX_COMPOSITE4] = "Composite4",
	[EM28XX_VMUX_SVIDEO]     = "S-Video",
	[EM28XX_VMUX_TELEVISION] = "Television",
	[EM28XX_VMUX_CABLE]      = "Cable TV",
	[EM28XX_VMUX_DVB]        = "DVB",
	[EM28XX_VMUX_DEBUG]      = "for debug only",
};

static int vidioc_enum_input(struct file *file, void *priv,
				struct v4l2_input *i)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	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) ||
		(EM28XX_VMUX_CABLE == INPUT(n)->type))
		i->type = V4L2_INPUT_TYPE_TUNER;

	i->std = dev->vdev->tvnorms;

	return 0;
}

static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;

	*i = dev->ctl_input;

	return 0;
}

static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
{
	struct em28xx_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;
	int                rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	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_fh   *fh    = priv;
	struct em28xx      *dev   = fh->dev;

	if (!dev->audio_mode.has_audio)
		return -EINVAL;

	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_fh   *fh  = priv;
	struct em28xx      *dev = fh->dev;


	if (!dev->audio_mode.has_audio)
		return -EINVAL;

	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_queryctrl(struct file *file, void *priv,
				struct v4l2_queryctrl *qc)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   id  = qc->id;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	memset(qc, 0, sizeof(*qc));

	qc->id = id;

	/* enumerate AC97 controls */
	if (dev->audio_mode.ac97 != EM28XX_NO_AC97) {
		rc = ac97_queryctrl(qc);
		if (!rc)
			return 0;
	}

	/* enumerate V4L2 device controls */
	v4l2_device_call_all(&dev->v4l2_dev, 0, core, queryctrl, qc);

	if (qc->type)
		return 0;
	else
		return -EINVAL;
}

/*
 * FIXME: This is an indirect way to check if a control exists at a
 * subdev. Instead of that hack, maybe the better would be to change all
 * subdevs to return -ENOIOCTLCMD, if an ioctl is not supported.
 */
static int check_subdev_ctrl(struct em28xx *dev, int id)
{
	struct v4l2_queryctrl qc;

	memset(&qc, 0, sizeof(qc));
	qc.id = id;

	/* enumerate V4L2 device controls */
	v4l2_device_call_all(&dev->v4l2_dev, 0, core, queryctrl, &qc);

	if (qc.type)
		return 0;
	else
		return -EINVAL;
}

static int vidioc_g_ctrl(struct file *file, void *priv,
				struct v4l2_control *ctrl)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;
	rc = 0;

	/* Set an AC97 control */
	if (dev->audio_mode.ac97 != EM28XX_NO_AC97)
		rc = ac97_get_ctrl(dev, ctrl);
	else
		rc = 1;

	/* It were not an AC97 control. Sends it to the v4l2 dev interface */
	if (rc == 1) {
		if (check_subdev_ctrl(dev, ctrl->id))
			return -EINVAL;

		v4l2_device_call_all(&dev->v4l2_dev, 0, core, g_ctrl, ctrl);
		rc = 0;
	}

	return rc;
}

static int vidioc_s_ctrl(struct file *file, void *priv,
				struct v4l2_control *ctrl)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	/* Set an AC97 control */
	if (dev->audio_mode.ac97 != EM28XX_NO_AC97)
		rc = ac97_set_ctrl(dev, ctrl);
	else
		rc = 1;

	/* It isn't an AC97 control. Sends it to the v4l2 dev interface */
	if (rc == 1) {
		rc = check_subdev_ctrl(dev, ctrl->id);
		if (!rc)
			v4l2_device_call_all(&dev->v4l2_dev, 0,
					     core, s_ctrl, ctrl);
		/*
		 * 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->value;
			rc = em28xx_audio_analog_set(dev);
			break;
		case V4L2_CID_AUDIO_VOLUME:
			dev->volume = ctrl->value;
			rc = em28xx_audio_analog_set(dev);
		}
	}
	return (rc < 0) ? rc : 0;
}

static int vidioc_g_tuner(struct file *file, void *priv,
				struct v4l2_tuner *t)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (0 != t->index)
		return -EINVAL;

	strcpy(t->name, "Tuner");
	t->type = V4L2_TUNER_ANALOG_TV;

	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, g_tuner, t);
	return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv,
				struct v4l2_tuner *t)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (0 != t->index)
		return -EINVAL;

	v4l2_device_call_all(&dev->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_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	f->type = fh->radio ? V4L2_TUNER_RADIO : V4L2_TUNER_ANALOG_TV;
	f->frequency = dev->ctl_freq;
	return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
				struct v4l2_frequency *f)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (0 != f->tuner)
		return -EINVAL;

	if (unlikely(0 == fh->radio && f->type != V4L2_TUNER_ANALOG_TV))
		return -EINVAL;
	if (unlikely(1 == fh->radio && f->type != V4L2_TUNER_RADIO))
		return -EINVAL;

	dev->ctl_freq = f->frequency;
	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, s_frequency, f);

	return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
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_chip_ident(struct file *file, void *priv,
	       struct v4l2_dbg_chip_ident *chip)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	chip->ident = V4L2_IDENT_NONE;
	chip->revision = 0;

	v4l2_device_call_all(&dev->v4l2_dev, 0, core, g_chip_ident, chip);

	return 0;
}


static int vidioc_g_register(struct file *file, void *priv,
			     struct v4l2_dbg_register *reg)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int ret;

	switch (reg->match.type) {
	case V4L2_CHIP_MATCH_AC97:
		ret = em28xx_read_ac97(dev, reg->reg);
		if (ret < 0)
			return ret;

		reg->val = ret;
		reg->size = 1;
		return 0;
	case V4L2_CHIP_MATCH_I2C_DRIVER:
		v4l2_device_call_all(&dev->v4l2_dev, 0, core, g_register, reg);
		return 0;
	case V4L2_CHIP_MATCH_I2C_ADDR:
		/* TODO: is this correct? */
		v4l2_device_call_all(&dev->v4l2_dev, 0, core, g_register, reg);
		return 0;
	default:
		if (!v4l2_chip_match_host(&reg->match))
			return -EINVAL;
	}

	/* 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 = 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,
			     struct v4l2_dbg_register *reg)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	__le16 buf;

	switch (reg->match.type) {
	case V4L2_CHIP_MATCH_AC97:
		return em28xx_write_ac97(dev, reg->reg, reg->val);
	case V4L2_CHIP_MATCH_I2C_DRIVER:
		v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_register, reg);
		return 0;
	case V4L2_CHIP_MATCH_I2C_ADDR:
		/* TODO: is this correct? */
		v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_register, reg);
		return 0;
	default:
		if (!v4l2_chip_match_host(&reg->match))
			return -EINVAL;
	}

	/* 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_cropcap(struct file *file, void *priv,
					struct v4l2_cropcap *cc)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	if (cc->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	cc->bounds.left = 0;
	cc->bounds.top = 0;
	cc->bounds.width = dev->width;
	cc->bounds.height = dev->height;
	cc->defrect = cc->bounds;
	cc->pixelaspect.numerator = 54;	/* 4:3 FIXME: remove magic numbers */
	cc->pixelaspect.denominator = 59;

	return 0;
}

static int vidioc_streamon(struct file *file, void *priv,
					enum v4l2_buf_type type)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc = -EINVAL;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (unlikely(type != fh->type))
		return -EINVAL;

	em28xx_videodbg("vidioc_streamon fh=%p t=%d fh->res=%d dev->res=%d\n",
			fh, type, fh->resources, dev->resources);

	if (unlikely(!res_get(fh, get_ressource(fh))))
		return -EBUSY;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		rc = videobuf_streamon(&fh->vb_vidq);
	else if (fh->type == V4L2_BUF_TYPE_VBI_CAPTURE)
		rc = videobuf_streamon(&fh->vb_vbiq);

	return rc;
}

static int vidioc_streamoff(struct file *file, void *priv,
					enum v4l2_buf_type type)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    fh->type != V4L2_BUF_TYPE_VBI_CAPTURE)
		return -EINVAL;
	if (type != fh->type)
		return -EINVAL;

	em28xx_videodbg("vidioc_streamoff fh=%p t=%d fh->res=%d dev->res=%d\n",
			fh, type, fh->resources, dev->resources);

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
		if (res_check(fh, EM28XX_RESOURCE_VIDEO)) {
			videobuf_streamoff(&fh->vb_vidq);
			res_free(fh, EM28XX_RESOURCE_VIDEO);
		}
	} else if (fh->type == V4L2_BUF_TYPE_VBI_CAPTURE) {
		if (res_check(fh, EM28XX_RESOURCE_VBI)) {
			videobuf_streamoff(&fh->vb_vbiq);
			res_free(fh, EM28XX_RESOURCE_VBI);
		}
	}

	return 0;
}

static int vidioc_querycap(struct file *file, void  *priv,
					struct v4l2_capability *cap)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	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));

	cap->capabilities =
			V4L2_CAP_SLICED_VBI_CAPTURE |
			V4L2_CAP_VIDEO_CAPTURE |
			V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;

	if (dev->vbi_dev)
		cap->capabilities |= V4L2_CAP_VBI_CAPTURE;

	if (dev->audio_mode.has_audio)
		cap->capabilities |= V4L2_CAP_AUDIO;

	if (dev->tuner_type != TUNER_ABSENT)
		cap->capabilities |= V4L2_CAP_TUNER;

	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_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	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;
	fsize->stepwise.min_width = 48;
	fsize->stepwise.min_height = 32;
	fsize->stepwise.max_width = maxw;
	fsize->stepwise.max_height = maxh;
	fsize->stepwise.step_width = 1;
	fsize->stepwise.step_height = 1;
	return 0;
}

/* Sliced VBI ioctls */
static int vidioc_g_fmt_sliced_vbi_cap(struct file *file, void *priv,
					struct v4l2_format *f)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	f->fmt.sliced.service_set = 0;
	v4l2_device_call_all(&dev->v4l2_dev, 0, vbi, g_sliced_fmt, &f->fmt.sliced);

	if (f->fmt.sliced.service_set == 0)
		rc = -EINVAL;

	return rc;
}

static int vidioc_try_set_sliced_vbi_cap(struct file *file, void *priv,
			struct v4l2_format *f)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	v4l2_device_call_all(&dev->v4l2_dev, 0, vbi, g_sliced_fmt, &f->fmt.sliced);

	if (f->fmt.sliced.service_set == 0)
		return -EINVAL;

	return 0;
}

/* RAW VBI ioctls */

static int vidioc_g_fmt_vbi_cap(struct file *file, void *priv,
				struct v4l2_format *format)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	format->fmt.vbi.samples_per_line = dev->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] = dev->vbi_height;
	format->fmt.vbi.count[1] = dev->vbi_height;

	/* Varies by video standard (NTSC, PAL, etc.) */
	if (dev->norm & V4L2_STD_525_60) {
		/* NTSC */
		format->fmt.vbi.start[0] = 10;
		format->fmt.vbi.start[1] = 273;
	} else if (dev->norm & V4L2_STD_625_50) {
		/* PAL */
		format->fmt.vbi.start[0] = 6;
		format->fmt.vbi.start[1] = 318;
	}

	return 0;
}

static int vidioc_s_fmt_vbi_cap(struct file *file, void *priv,
				struct v4l2_format *format)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;

	format->fmt.vbi.samples_per_line = dev->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] = dev->vbi_height;
	format->fmt.vbi.count[1] = dev->vbi_height;

	/* Varies by video standard (NTSC, PAL, etc.) */
	if (dev->norm & V4L2_STD_525_60) {
		/* NTSC */
		format->fmt.vbi.start[0] = 10;
		format->fmt.vbi.start[1] = 273;
	} else if (dev->norm & V4L2_STD_625_50) {
		/* PAL */
		format->fmt.vbi.start[0] = 6;
		format->fmt.vbi.start[1] = 318;
	}

	return 0;
}

static int vidioc_reqbufs(struct file *file, void *priv,
			  struct v4l2_requestbuffers *rb)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return videobuf_reqbufs(&fh->vb_vidq, rb);
	else
		return videobuf_reqbufs(&fh->vb_vbiq, rb);
}

static int vidioc_querybuf(struct file *file, void *priv,
			   struct v4l2_buffer *b)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return videobuf_querybuf(&fh->vb_vidq, b);
	else {
		/* FIXME: I'm not sure yet whether this is a bug in zvbi or
		   the videobuf framework, but we probably shouldn't be
		   returning a buffer larger than that which was asked for.
		   At a minimum, it causes a crash in zvbi since it does
		   a memcpy based on the source buffer length */
		int result = videobuf_querybuf(&fh->vb_vbiq, b);
		b->length = dev->vbi_width * dev->vbi_height * 2;

		return result;
	}
}

static int vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *b)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return videobuf_qbuf(&fh->vb_vidq, b);
	else
		return videobuf_qbuf(&fh->vb_vbiq, b);
}

static int vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *b)
{
	struct em28xx_fh      *fh  = priv;
	struct em28xx         *dev = fh->dev;
	int                   rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return videobuf_dqbuf(&fh->vb_vidq, b, file->f_flags &
				      O_NONBLOCK);
	else
		return videobuf_dqbuf(&fh->vb_vbiq, b, file->f_flags &
				      O_NONBLOCK);
}

/* ----------------------------------------------------------- */
/* RADIO ESPECIFIC IOCTLS                                      */
/* ----------------------------------------------------------- */

static int radio_querycap(struct file *file, void  *priv,
			  struct v4l2_capability *cap)
{
	struct em28xx *dev = ((struct em28xx_fh *)priv)->dev;

	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));

	cap->capabilities = V4L2_CAP_TUNER;
	return 0;
}

static int radio_g_tuner(struct file *file, void *priv,
			 struct v4l2_tuner *t)
{
	struct em28xx *dev = ((struct em28xx_fh *)priv)->dev;

	if (unlikely(t->index > 0))
		return -EINVAL;

	strcpy(t->name, "Radio");
	t->type = V4L2_TUNER_RADIO;

	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, g_tuner, t);

	return 0;
}

static int radio_enum_input(struct file *file, void *priv,
			    struct v4l2_input *i)
{
	if (i->index != 0)
		return -EINVAL;
	strcpy(i->name, "Radio");
	i->type = V4L2_INPUT_TYPE_TUNER;

	return 0;
}

static int radio_g_audio(struct file *file, void *priv, struct v4l2_audio *a)
{
	if (unlikely(a->index))
		return -EINVAL;

	strcpy(a->name, "Radio");
	return 0;
}

static int radio_s_tuner(struct file *file, void *priv,
			 struct v4l2_tuner *t)
{
	struct em28xx *dev = ((struct em28xx_fh *)priv)->dev;

	if (0 != t->index)
		return -EINVAL;

	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, s_tuner, t);

	return 0;
}

static int radio_s_audio(struct file *file, void *fh,
			 const struct v4l2_audio *a)
{
	return 0;
}

static int radio_s_input(struct file *file, void *fh, unsigned int i)
{
	return 0;
}

static int radio_queryctrl(struct file *file, void *priv,
			   struct v4l2_queryctrl *qc)
{
	int i;

	if (qc->id <  V4L2_CID_BASE ||
		qc->id >= V4L2_CID_LASTP1)
		return -EINVAL;

	for (i = 0; i < ARRAY_SIZE(ac97_qctrl); i++) {
		if (qc->id && qc->id == ac97_qctrl[i].id) {
			memcpy(qc, &(ac97_qctrl[i]), sizeof(*qc));
			return 0;
		}
	}

	return -EINVAL;
}

/*
 * em28xx_v4l2_open()
 * inits the device and starts isoc transfer
 */
static int em28xx_v4l2_open(struct file *filp)
{
	int errCode = 0, radio = 0;
	struct video_device *vdev = video_devdata(filp);
	struct em28xx *dev = video_drvdata(filp);
	enum v4l2_buf_type fh_type = 0;
	struct em28xx_fh *fh;
	enum v4l2_field field;

	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:
		radio = 1;
		break;
	}

	em28xx_videodbg("open dev=%s type=%s users=%d\n",
			video_device_node_name(vdev), v4l2_type_names[fh_type],
			dev->users);


	if (mutex_lock_interruptible(&dev->lock))
		return -ERESTARTSYS;
	fh = kzalloc(sizeof(struct em28xx_fh), GFP_KERNEL);
	if (!fh) {
		em28xx_errdev("em28xx-video.c: Out of memory?!\n");
		mutex_unlock(&dev->lock);
		return -ENOMEM;
	}
	fh->dev = dev;
	fh->radio = radio;
	fh->type = fh_type;
	filp->private_data = fh;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE && dev->users == 0) {
		em28xx_set_mode(dev, EM28XX_ANALOG_MODE);
		em28xx_set_alternate(dev);
		em28xx_resolution_set(dev);

		/* Needed, since GPIO might have disabled power of
		   some i2c device
		 */
		em28xx_wake_i2c(dev);

	}
	if (fh->radio) {
		em28xx_videodbg("video_open: setting radio device\n");
		v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, s_radio);
	}

	dev->users++;

	if (dev->progressive)
		field = V4L2_FIELD_NONE;
	else
		field = V4L2_FIELD_INTERLACED;

	videobuf_queue_vmalloc_init(&fh->vb_vidq, &em28xx_video_qops,
				    NULL, &dev->slock,
				    V4L2_BUF_TYPE_VIDEO_CAPTURE, field,
				    sizeof(struct em28xx_buffer), fh, &dev->lock);

	videobuf_queue_vmalloc_init(&fh->vb_vbiq, &em28xx_vbi_qops,
				    NULL, &dev->slock,
				    V4L2_BUF_TYPE_VBI_CAPTURE,
				    V4L2_FIELD_SEQ_TB,
				    sizeof(struct em28xx_buffer), fh, &dev->lock);
	mutex_unlock(&dev->lock);

	return errCode;
}

/*
 * em28xx_realease_resources()
 * unregisters the v4l2,i2c and usb devices
 * called when the device gets disconected or at module unload
*/
void em28xx_release_analog_resources(struct em28xx *dev)
{

	/*FIXME: I2C IR should be disconnected */

	if (dev->radio_dev) {
		if (video_is_registered(dev->radio_dev))
			video_unregister_device(dev->radio_dev);
		else
			video_device_release(dev->radio_dev);
		dev->radio_dev = NULL;
	}
	if (dev->vbi_dev) {
		em28xx_info("V4L2 device %s deregistered\n",
			    video_device_node_name(dev->vbi_dev));
		if (video_is_registered(dev->vbi_dev))
			video_unregister_device(dev->vbi_dev);
		else
			video_device_release(dev->vbi_dev);
		dev->vbi_dev = NULL;
	}
	if (dev->vdev) {
		em28xx_info("V4L2 device %s deregistered\n",
			    video_device_node_name(dev->vdev));
		if (video_is_registered(dev->vdev))
			video_unregister_device(dev->vdev);
		else
			video_device_release(dev->vdev);
		dev->vdev = NULL;
	}
}

/*
 * 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_fh *fh  = filp->private_data;
	struct em28xx    *dev = fh->dev;
	int              errCode;

	em28xx_videodbg("users=%d\n", dev->users);

	mutex_lock(&dev->lock);
	if (res_check(fh, EM28XX_RESOURCE_VIDEO)) {
		videobuf_stop(&fh->vb_vidq);
		res_free(fh, EM28XX_RESOURCE_VIDEO);
	}

	if (res_check(fh, EM28XX_RESOURCE_VBI)) {
		videobuf_stop(&fh->vb_vbiq);
		res_free(fh, EM28XX_RESOURCE_VBI);
	}

	if (dev->users == 1) {
		/* the device is already disconnect,
		   free the remaining resources */
		if (dev->state & DEV_DISCONNECTED) {
			em28xx_release_resources(dev);
			kfree(dev->alt_max_pkt_size);
			mutex_unlock(&dev->lock);
			kfree(dev);
			kfree(fh);
			return 0;
		}

		/* Save some power by putting tuner to sleep */
		v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_power, 0);

		/* do this before setting alternate! */
		em28xx_uninit_isoc(dev, EM28XX_ANALOG_MODE);
		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);
		}
	}

	videobuf_mmap_free(&fh->vb_vidq);
	videobuf_mmap_free(&fh->vb_vbiq);
	kfree(fh);
	dev->users--;
	mutex_unlock(&dev->lock);
	return 0;
}

/*
 * em28xx_v4l2_read()
 * will allocate buffers when called for the first time
 */
static ssize_t
em28xx_v4l2_read(struct file *filp, char __user *buf, size_t count,
		 loff_t *pos)
{
	struct em28xx_fh *fh = filp->private_data;
	struct em28xx *dev = fh->dev;
	int rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (mutex_lock_interruptible(&dev->lock))
		return -ERESTARTSYS;
	/* FIXME: read() is not prepared to allow changing the video
	   resolution while streaming. Seems a bug at em28xx_set_fmt
	 */

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
		if (res_locked(dev, EM28XX_RESOURCE_VIDEO))
			rc = -EBUSY;
		else
			rc = videobuf_read_stream(&fh->vb_vidq, buf, count, pos, 0,
					filp->f_flags & O_NONBLOCK);
	} else if (fh->type == V4L2_BUF_TYPE_VBI_CAPTURE) {
		if (!res_get(fh, EM28XX_RESOURCE_VBI))
			rc = -EBUSY;
		else
			rc = videobuf_read_stream(&fh->vb_vbiq, buf, count, pos, 0,
					filp->f_flags & O_NONBLOCK);
	}
	mutex_unlock(&dev->lock);

	return rc;
}

/*
 * em28xx_poll()
 * will allocate buffers when called for the first time
 */
static unsigned int em28xx_poll(struct file *filp, poll_table *wait)
{
	struct em28xx_fh *fh = filp->private_data;
	struct em28xx *dev = fh->dev;
	int rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
		if (!res_get(fh, EM28XX_RESOURCE_VIDEO))
			return POLLERR;
		return videobuf_poll_stream(filp, &fh->vb_vidq, wait);
	} else if (fh->type == V4L2_BUF_TYPE_VBI_CAPTURE) {
		if (!res_get(fh, EM28XX_RESOURCE_VBI))
			return POLLERR;
		return videobuf_poll_stream(filp, &fh->vb_vbiq, wait);
	} else {
		return POLLERR;
	}
}

static unsigned int em28xx_v4l2_poll(struct file *filp, poll_table *wait)
{
	struct em28xx_fh *fh = filp->private_data;
	struct em28xx *dev = fh->dev;
	unsigned int res;

	mutex_lock(&dev->lock);
	res = em28xx_poll(filp, wait);
	mutex_unlock(&dev->lock);
	return res;
}

/*
 * em28xx_v4l2_mmap()
 */
static int em28xx_v4l2_mmap(struct file *filp, struct vm_area_struct *vma)
{
	struct em28xx_fh *fh    = filp->private_data;
	struct em28xx	 *dev   = fh->dev;
	int		 rc;

	rc = check_dev(dev);
	if (rc < 0)
		return rc;

	if (mutex_lock_interruptible(&dev->lock))
		return -ERESTARTSYS;
	if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		rc = videobuf_mmap_mapper(&fh->vb_vidq, vma);
	else if (fh->type == V4L2_BUF_TYPE_VBI_CAPTURE)
		rc = videobuf_mmap_mapper(&fh->vb_vbiq, vma);
	mutex_unlock(&dev->lock);

	em28xx_videodbg("vma start=0x%08lx, size=%ld, ret=%d\n",
		(unsigned long)vma->vm_start,
		(unsigned long)vma->vm_end-(unsigned long)vma->vm_start,
		rc);

	return rc;
}

static const struct v4l2_file_operations em28xx_v4l_fops = {
	.owner         = THIS_MODULE,
	.open          = em28xx_v4l2_open,
	.release       = em28xx_v4l2_close,
	.read          = em28xx_v4l2_read,
	.poll          = em28xx_v4l2_poll,
	.mmap          = em28xx_v4l2_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_s_fmt_vbi_cap       = vidioc_s_fmt_vbi_cap,
	.vidioc_enum_framesizes     = vidioc_enum_framesizes,
	.vidioc_g_audio             = vidioc_g_audio,
	.vidioc_s_audio             = vidioc_s_audio,
	.vidioc_cropcap             = vidioc_cropcap,
	.vidioc_g_fmt_sliced_vbi_cap   = vidioc_g_fmt_sliced_vbi_cap,
	.vidioc_try_fmt_sliced_vbi_cap = vidioc_try_set_sliced_vbi_cap,
	.vidioc_s_fmt_sliced_vbi_cap   = vidioc_try_set_sliced_vbi_cap,

	.vidioc_reqbufs             = vidioc_reqbufs,
	.vidioc_querybuf            = vidioc_querybuf,
	.vidioc_qbuf                = vidioc_qbuf,
	.vidioc_dqbuf               = vidioc_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_queryctrl           = vidioc_queryctrl,
	.vidioc_g_ctrl              = vidioc_g_ctrl,
	.vidioc_s_ctrl              = vidioc_s_ctrl,
	.vidioc_streamon            = vidioc_streamon,
	.vidioc_streamoff           = vidioc_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,
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.vidioc_g_register          = vidioc_g_register,
	.vidioc_s_register          = vidioc_s_register,
	.vidioc_g_chip_ident        = vidioc_g_chip_ident,
#endif
};

static const struct video_device em28xx_video_template = {
	.fops                       = &em28xx_v4l_fops,
	.release                    = video_device_release,
	.ioctl_ops 		    = &video_ioctl_ops,

	.tvnorms                    = V4L2_STD_ALL,
	.current_norm               = V4L2_STD_PAL,
};

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      = radio_querycap,
	.vidioc_g_tuner       = radio_g_tuner,
	.vidioc_enum_input    = radio_enum_input,
	.vidioc_g_audio       = radio_g_audio,
	.vidioc_s_tuner       = radio_s_tuner,
	.vidioc_s_audio       = radio_s_audio,
	.vidioc_s_input       = radio_s_input,
	.vidioc_queryctrl     = radio_queryctrl,
	.vidioc_g_ctrl        = vidioc_g_ctrl,
	.vidioc_s_ctrl        = vidioc_s_ctrl,
	.vidioc_g_frequency   = vidioc_g_frequency,
	.vidioc_s_frequency   = vidioc_s_frequency,
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.vidioc_g_register    = vidioc_g_register,
	.vidioc_s_register    = vidioc_s_register,
#endif
};

static struct video_device em28xx_radio_template = {
	.name                 = "em28xx-radio",
	.fops                 = &radio_fops,
	.ioctl_ops 	      = &radio_ioctl_ops,
};

/******************************** usb interface ******************************/



static struct video_device *em28xx_vdev_init(struct em28xx *dev,
					const struct video_device *template,
					const char *type_name)
{
	struct video_device *vfd;

	vfd = video_device_alloc();
	if (NULL == vfd)
		return NULL;

	*vfd		= *template;
	vfd->v4l2_dev	= &dev->v4l2_dev;
	vfd->release	= video_device_release;
	vfd->debug	= video_debug;
	vfd->lock	= &dev->lock;

	snprintf(vfd->name, sizeof(vfd->name), "%s %s",
		 dev->name, type_name);

	video_set_drvdata(vfd, dev);
	return vfd;
}

int em28xx_register_analog_devices(struct em28xx *dev)
{
      u8 val;
	int ret;
	unsigned int maxw;

	printk(KERN_INFO "%s: v4l2 driver version %s\n",
		dev->name, EM28XX_VERSION);

	/* set default norm */
	dev->norm = em28xx_video_template.current_norm;
	v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_std, dev->norm);
	dev->interlaced = EM28XX_INTERLACED_DEFAULT;

	/* Analog specific initialization */
	dev->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);
	em28xx_colorlevels_set_default(dev);
	em28xx_compression_disable(dev);

	/* allocate and fill video video_device struct */
	dev->vdev = em28xx_vdev_init(dev, &em28xx_video_template, "video");
	if (!dev->vdev) {
		em28xx_errdev("cannot allocate video_device.\n");
		return -ENODEV;
	}

	/* register v4l2 video video_device */
	ret = video_register_device(dev->vdev, VFL_TYPE_GRABBER,
				       video_nr[dev->devno]);
	if (ret) {
		em28xx_errdev("unable to register video device (error=%i).\n",
			      ret);
		return ret;
	}

	/* Allocate and fill vbi video_device struct */
	if (em28xx_vbi_supported(dev) == 1) {
		dev->vbi_dev = em28xx_vdev_init(dev, &em28xx_video_template,
						"vbi");

		/* register v4l2 vbi video_device */
		ret = video_register_device(dev->vbi_dev, VFL_TYPE_VBI,
					    vbi_nr[dev->devno]);
		if (ret < 0) {
			em28xx_errdev("unable to register vbi device\n");
			return ret;
		}
	}

	if (em28xx_boards[dev->model].radio.type == EM28XX_RADIO) {
		dev->radio_dev = em28xx_vdev_init(dev, &em28xx_radio_template,
						  "radio");
		if (!dev->radio_dev) {
			em28xx_errdev("cannot allocate video_device.\n");
			return -ENODEV;
		}
		ret = video_register_device(dev->radio_dev, VFL_TYPE_RADIO,
					    radio_nr[dev->devno]);
		if (ret < 0) {
			em28xx_errdev("can't register radio device\n");
			return ret;
		}
		em28xx_info("Registered radio device as %s\n",
			    video_device_node_name(dev->radio_dev));
	}

	em28xx_info("V4L2 video device registered as %s\n",
		    video_device_node_name(dev->vdev));

	if (dev->vbi_dev)
		em28xx_info("V4L2 VBI device registered as %s\n",
			    video_device_node_name(dev->vbi_dev));

	return 0;
}