/*
 * ispvideo.c
 *
 * TI OMAP3 ISP - Generic video node
 *
 * Copyright (C) 2009-2010 Nokia Corporation
 *
 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 *	     Sakari Ailus <sakari.ailus@iki.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <asm/cacheflush.h>
#include <linux/clk.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/omap-iommu.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-ioctl.h>

#include "ispvideo.h"
#include "isp.h"


/* -----------------------------------------------------------------------------
 * Helper functions
 */

/*
 * NOTE: When adding new media bus codes, always remember to add
 * corresponding in-memory formats to the table below!!!
 */
static struct isp_format_info formats[] = {
	{ V4L2_MBUS_FMT_Y8_1X8, V4L2_MBUS_FMT_Y8_1X8,
	  V4L2_MBUS_FMT_Y8_1X8, V4L2_MBUS_FMT_Y8_1X8,
	  V4L2_PIX_FMT_GREY, 8, 1, },
	{ V4L2_MBUS_FMT_Y10_1X10, V4L2_MBUS_FMT_Y10_1X10,
	  V4L2_MBUS_FMT_Y10_1X10, V4L2_MBUS_FMT_Y8_1X8,
	  V4L2_PIX_FMT_Y10, 10, 2, },
	{ V4L2_MBUS_FMT_Y12_1X12, V4L2_MBUS_FMT_Y10_1X10,
	  V4L2_MBUS_FMT_Y12_1X12, V4L2_MBUS_FMT_Y8_1X8,
	  V4L2_PIX_FMT_Y12, 12, 2, },
	{ V4L2_MBUS_FMT_SBGGR8_1X8, V4L2_MBUS_FMT_SBGGR8_1X8,
	  V4L2_MBUS_FMT_SBGGR8_1X8, V4L2_MBUS_FMT_SBGGR8_1X8,
	  V4L2_PIX_FMT_SBGGR8, 8, 1, },
	{ V4L2_MBUS_FMT_SGBRG8_1X8, V4L2_MBUS_FMT_SGBRG8_1X8,
	  V4L2_MBUS_FMT_SGBRG8_1X8, V4L2_MBUS_FMT_SGBRG8_1X8,
	  V4L2_PIX_FMT_SGBRG8, 8, 1, },
	{ V4L2_MBUS_FMT_SGRBG8_1X8, V4L2_MBUS_FMT_SGRBG8_1X8,
	  V4L2_MBUS_FMT_SGRBG8_1X8, V4L2_MBUS_FMT_SGRBG8_1X8,
	  V4L2_PIX_FMT_SGRBG8, 8, 1, },
	{ V4L2_MBUS_FMT_SRGGB8_1X8, V4L2_MBUS_FMT_SRGGB8_1X8,
	  V4L2_MBUS_FMT_SRGGB8_1X8, V4L2_MBUS_FMT_SRGGB8_1X8,
	  V4L2_PIX_FMT_SRGGB8, 8, 1, },
	{ V4L2_MBUS_FMT_SBGGR10_DPCM8_1X8, V4L2_MBUS_FMT_SBGGR10_DPCM8_1X8,
	  V4L2_MBUS_FMT_SBGGR10_1X10, 0,
	  V4L2_PIX_FMT_SBGGR10DPCM8, 8, 1, },
	{ V4L2_MBUS_FMT_SGBRG10_DPCM8_1X8, V4L2_MBUS_FMT_SGBRG10_DPCM8_1X8,
	  V4L2_MBUS_FMT_SGBRG10_1X10, 0,
	  V4L2_PIX_FMT_SGBRG10DPCM8, 8, 1, },
	{ V4L2_MBUS_FMT_SGRBG10_DPCM8_1X8, V4L2_MBUS_FMT_SGRBG10_DPCM8_1X8,
	  V4L2_MBUS_FMT_SGRBG10_1X10, 0,
	  V4L2_PIX_FMT_SGRBG10DPCM8, 8, 1, },
	{ V4L2_MBUS_FMT_SRGGB10_DPCM8_1X8, V4L2_MBUS_FMT_SRGGB10_DPCM8_1X8,
	  V4L2_MBUS_FMT_SRGGB10_1X10, 0,
	  V4L2_PIX_FMT_SRGGB10DPCM8, 8, 1, },
	{ V4L2_MBUS_FMT_SBGGR10_1X10, V4L2_MBUS_FMT_SBGGR10_1X10,
	  V4L2_MBUS_FMT_SBGGR10_1X10, V4L2_MBUS_FMT_SBGGR8_1X8,
	  V4L2_PIX_FMT_SBGGR10, 10, 2, },
	{ V4L2_MBUS_FMT_SGBRG10_1X10, V4L2_MBUS_FMT_SGBRG10_1X10,
	  V4L2_MBUS_FMT_SGBRG10_1X10, V4L2_MBUS_FMT_SGBRG8_1X8,
	  V4L2_PIX_FMT_SGBRG10, 10, 2, },
	{ V4L2_MBUS_FMT_SGRBG10_1X10, V4L2_MBUS_FMT_SGRBG10_1X10,
	  V4L2_MBUS_FMT_SGRBG10_1X10, V4L2_MBUS_FMT_SGRBG8_1X8,
	  V4L2_PIX_FMT_SGRBG10, 10, 2, },
	{ V4L2_MBUS_FMT_SRGGB10_1X10, V4L2_MBUS_FMT_SRGGB10_1X10,
	  V4L2_MBUS_FMT_SRGGB10_1X10, V4L2_MBUS_FMT_SRGGB8_1X8,
	  V4L2_PIX_FMT_SRGGB10, 10, 2, },
	{ V4L2_MBUS_FMT_SBGGR12_1X12, V4L2_MBUS_FMT_SBGGR10_1X10,
	  V4L2_MBUS_FMT_SBGGR12_1X12, V4L2_MBUS_FMT_SBGGR8_1X8,
	  V4L2_PIX_FMT_SBGGR12, 12, 2, },
	{ V4L2_MBUS_FMT_SGBRG12_1X12, V4L2_MBUS_FMT_SGBRG10_1X10,
	  V4L2_MBUS_FMT_SGBRG12_1X12, V4L2_MBUS_FMT_SGBRG8_1X8,
	  V4L2_PIX_FMT_SGBRG12, 12, 2, },
	{ V4L2_MBUS_FMT_SGRBG12_1X12, V4L2_MBUS_FMT_SGRBG10_1X10,
	  V4L2_MBUS_FMT_SGRBG12_1X12, V4L2_MBUS_FMT_SGRBG8_1X8,
	  V4L2_PIX_FMT_SGRBG12, 12, 2, },
	{ V4L2_MBUS_FMT_SRGGB12_1X12, V4L2_MBUS_FMT_SRGGB10_1X10,
	  V4L2_MBUS_FMT_SRGGB12_1X12, V4L2_MBUS_FMT_SRGGB8_1X8,
	  V4L2_PIX_FMT_SRGGB12, 12, 2, },
	{ V4L2_MBUS_FMT_UYVY8_1X16, V4L2_MBUS_FMT_UYVY8_1X16,
	  V4L2_MBUS_FMT_UYVY8_1X16, 0,
	  V4L2_PIX_FMT_UYVY, 16, 2, },
	{ V4L2_MBUS_FMT_YUYV8_1X16, V4L2_MBUS_FMT_YUYV8_1X16,
	  V4L2_MBUS_FMT_YUYV8_1X16, 0,
	  V4L2_PIX_FMT_YUYV, 16, 2, },
	{ V4L2_MBUS_FMT_UYVY8_2X8, V4L2_MBUS_FMT_UYVY8_2X8,
	  V4L2_MBUS_FMT_UYVY8_2X8, 0,
	  V4L2_PIX_FMT_UYVY, 8, 2, },
	{ V4L2_MBUS_FMT_YUYV8_2X8, V4L2_MBUS_FMT_YUYV8_2X8,
	  V4L2_MBUS_FMT_YUYV8_2X8, 0,
	  V4L2_PIX_FMT_YUYV, 8, 2, },
	/* Empty entry to catch the unsupported pixel code (0) used by the CCDC
	 * module and avoid NULL pointer dereferences.
	 */
	{ 0, }
};

const struct isp_format_info *
omap3isp_video_format_info(enum v4l2_mbus_pixelcode code)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
		if (formats[i].code == code)
			return &formats[i];
	}

	return NULL;
}

/*
 * isp_video_mbus_to_pix - Convert v4l2_mbus_framefmt to v4l2_pix_format
 * @video: ISP video instance
 * @mbus: v4l2_mbus_framefmt format (input)
 * @pix: v4l2_pix_format format (output)
 *
 * Fill the output pix structure with information from the input mbus format.
 * The bytesperline and sizeimage fields are computed from the requested bytes
 * per line value in the pix format and information from the video instance.
 *
 * Return the number of padding bytes at end of line.
 */
static unsigned int isp_video_mbus_to_pix(const struct isp_video *video,
					  const struct v4l2_mbus_framefmt *mbus,
					  struct v4l2_pix_format *pix)
{
	unsigned int bpl = pix->bytesperline;
	unsigned int min_bpl;
	unsigned int i;

	memset(pix, 0, sizeof(*pix));
	pix->width = mbus->width;
	pix->height = mbus->height;

	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
		if (formats[i].code == mbus->code)
			break;
	}

	if (WARN_ON(i == ARRAY_SIZE(formats)))
		return 0;

	min_bpl = pix->width * formats[i].bpp;

	/* Clamp the requested bytes per line value. If the maximum bytes per
	 * line value is zero, the module doesn't support user configurable line
	 * sizes. Override the requested value with the minimum in that case.
	 */
	if (video->bpl_max)
		bpl = clamp(bpl, min_bpl, video->bpl_max);
	else
		bpl = min_bpl;

	if (!video->bpl_zero_padding || bpl != min_bpl)
		bpl = ALIGN(bpl, video->bpl_alignment);

	pix->pixelformat = formats[i].pixelformat;
	pix->bytesperline = bpl;
	pix->sizeimage = pix->bytesperline * pix->height;
	pix->colorspace = mbus->colorspace;
	pix->field = mbus->field;

	return bpl - min_bpl;
}

static void isp_video_pix_to_mbus(const struct v4l2_pix_format *pix,
				  struct v4l2_mbus_framefmt *mbus)
{
	unsigned int i;

	memset(mbus, 0, sizeof(*mbus));
	mbus->width = pix->width;
	mbus->height = pix->height;

	/* Skip the last format in the loop so that it will be selected if no
	 * match is found.
	 */
	for (i = 0; i < ARRAY_SIZE(formats) - 1; ++i) {
		if (formats[i].pixelformat == pix->pixelformat)
			break;
	}

	mbus->code = formats[i].code;
	mbus->colorspace = pix->colorspace;
	mbus->field = pix->field;
}

static struct v4l2_subdev *
isp_video_remote_subdev(struct isp_video *video, u32 *pad)
{
	struct media_pad *remote;

	remote = media_entity_remote_pad(&video->pad);

	if (remote == NULL ||
	    media_entity_type(remote->entity) != MEDIA_ENT_T_V4L2_SUBDEV)
		return NULL;

	if (pad)
		*pad = remote->index;

	return media_entity_to_v4l2_subdev(remote->entity);
}

/* Return a pointer to the ISP video instance at the far end of the pipeline. */
static int isp_video_get_graph_data(struct isp_video *video,
				    struct isp_pipeline *pipe)
{
	struct media_entity_graph graph;
	struct media_entity *entity = &video->video.entity;
	struct media_device *mdev = entity->parent;
	struct isp_video *far_end = NULL;

	mutex_lock(&mdev->graph_mutex);
	media_entity_graph_walk_start(&graph, entity);

	while ((entity = media_entity_graph_walk_next(&graph))) {
		struct isp_video *__video;

		pipe->entities |= 1 << entity->id;

		if (far_end != NULL)
			continue;

		if (entity == &video->video.entity)
			continue;

		if (media_entity_type(entity) != MEDIA_ENT_T_DEVNODE)
			continue;

		__video = to_isp_video(media_entity_to_video_device(entity));
		if (__video->type != video->type)
			far_end = __video;
	}

	mutex_unlock(&mdev->graph_mutex);

	if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
		pipe->input = far_end;
		pipe->output = video;
	} else {
		if (far_end == NULL)
			return -EPIPE;

		pipe->input = video;
		pipe->output = far_end;
	}

	return 0;
}

/*
 * Validate a pipeline by checking both ends of all links for format
 * discrepancies.
 *
 * Compute the minimum time per frame value as the maximum of time per frame
 * limits reported by every block in the pipeline.
 *
 * Return 0 if all formats match, or -EPIPE if at least one link is found with
 * different formats on its two ends or if the pipeline doesn't start with a
 * video source (either a subdev with no input pad, or a non-subdev entity).
 */
static int isp_video_validate_pipeline(struct isp_pipeline *pipe)
{
	struct isp_device *isp = pipe->output->isp;
	struct media_pad *pad;
	struct v4l2_subdev *subdev;

	subdev = isp_video_remote_subdev(pipe->output, NULL);
	if (subdev == NULL)
		return -EPIPE;

	while (1) {
		/* Retrieve the sink format */
		pad = &subdev->entity.pads[0];
		if (!(pad->flags & MEDIA_PAD_FL_SINK))
			break;

		/* Update the maximum frame rate */
		if (subdev == &isp->isp_res.subdev)
			omap3isp_resizer_max_rate(&isp->isp_res,
						  &pipe->max_rate);

		/* Retrieve the source format. Return an error if no source
		 * entity can be found, and stop checking the pipeline if the
		 * source entity isn't a subdev.
		 */
		pad = media_entity_remote_pad(pad);
		if (pad == NULL)
			return -EPIPE;

		if (media_entity_type(pad->entity) != MEDIA_ENT_T_V4L2_SUBDEV)
			break;

		subdev = media_entity_to_v4l2_subdev(pad->entity);
	}

	return 0;
}

static int
__isp_video_get_format(struct isp_video *video, struct v4l2_format *format)
{
	struct v4l2_subdev_format fmt;
	struct v4l2_subdev *subdev;
	u32 pad;
	int ret;

	subdev = isp_video_remote_subdev(video, &pad);
	if (subdev == NULL)
		return -EINVAL;

	fmt.pad = pad;
	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;

	mutex_lock(&video->mutex);
	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
	mutex_unlock(&video->mutex);

	if (ret)
		return ret;

	format->type = video->type;
	return isp_video_mbus_to_pix(video, &fmt.format, &format->fmt.pix);
}

static int
isp_video_check_format(struct isp_video *video, struct isp_video_fh *vfh)
{
	struct v4l2_format format;
	int ret;

	memcpy(&format, &vfh->format, sizeof(format));
	ret = __isp_video_get_format(video, &format);
	if (ret < 0)
		return ret;

	if (vfh->format.fmt.pix.pixelformat != format.fmt.pix.pixelformat ||
	    vfh->format.fmt.pix.height != format.fmt.pix.height ||
	    vfh->format.fmt.pix.width != format.fmt.pix.width ||
	    vfh->format.fmt.pix.bytesperline != format.fmt.pix.bytesperline ||
	    vfh->format.fmt.pix.sizeimage != format.fmt.pix.sizeimage)
		return -EINVAL;

	return ret;
}

/* -----------------------------------------------------------------------------
 * IOMMU management
 */

#define IOMMU_FLAG	(IOVMF_ENDIAN_LITTLE | IOVMF_ELSZ_8)

/*
 * ispmmu_vmap - Wrapper for Virtual memory mapping of a scatter gather list
 * @dev: Device pointer specific to the OMAP3 ISP.
 * @sglist: Pointer to source Scatter gather list to allocate.
 * @sglen: Number of elements of the scatter-gatter list.
 *
 * Returns a resulting mapped device address by the ISP MMU, or -ENOMEM if
 * we ran out of memory.
 */
static dma_addr_t
ispmmu_vmap(struct isp_device *isp, const struct scatterlist *sglist, int sglen)
{
	struct sg_table *sgt;
	u32 da;

	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
	if (sgt == NULL)
		return -ENOMEM;

	sgt->sgl = (struct scatterlist *)sglist;
	sgt->nents = sglen;
	sgt->orig_nents = sglen;

	da = omap_iommu_vmap(isp->domain, isp->dev, 0, sgt, IOMMU_FLAG);
	if (IS_ERR_VALUE(da))
		kfree(sgt);

	return da;
}

/*
 * ispmmu_vunmap - Unmap a device address from the ISP MMU
 * @dev: Device pointer specific to the OMAP3 ISP.
 * @da: Device address generated from a ispmmu_vmap call.
 */
static void ispmmu_vunmap(struct isp_device *isp, dma_addr_t da)
{
	struct sg_table *sgt;

	sgt = omap_iommu_vunmap(isp->domain, isp->dev, (u32)da);
	kfree(sgt);
}

/* -----------------------------------------------------------------------------
 * Video queue operations
 */

static void isp_video_queue_prepare(struct isp_video_queue *queue,
				    unsigned int *nbuffers, unsigned int *size)
{
	struct isp_video_fh *vfh =
		container_of(queue, struct isp_video_fh, queue);
	struct isp_video *video = vfh->video;

	*size = vfh->format.fmt.pix.sizeimage;
	if (*size == 0)
		return;

	*nbuffers = min(*nbuffers, video->capture_mem / PAGE_ALIGN(*size));
}

static void isp_video_buffer_cleanup(struct isp_video_buffer *buf)
{
	struct isp_video_fh *vfh = isp_video_queue_to_isp_video_fh(buf->queue);
	struct isp_buffer *buffer = to_isp_buffer(buf);
	struct isp_video *video = vfh->video;

	if (buffer->isp_addr) {
		ispmmu_vunmap(video->isp, buffer->isp_addr);
		buffer->isp_addr = 0;
	}
}

static int isp_video_buffer_prepare(struct isp_video_buffer *buf)
{
	struct isp_video_fh *vfh = isp_video_queue_to_isp_video_fh(buf->queue);
	struct isp_buffer *buffer = to_isp_buffer(buf);
	struct isp_video *video = vfh->video;
	unsigned long addr;

	addr = ispmmu_vmap(video->isp, buf->sglist, buf->sglen);
	if (IS_ERR_VALUE(addr))
		return -EIO;

	if (!IS_ALIGNED(addr, 32)) {
		dev_dbg(video->isp->dev, "Buffer address must be "
			"aligned to 32 bytes boundary.\n");
		ispmmu_vunmap(video->isp, buffer->isp_addr);
		return -EINVAL;
	}

	buf->vbuf.bytesused = vfh->format.fmt.pix.sizeimage;
	buffer->isp_addr = addr;
	return 0;
}

/*
 * isp_video_buffer_queue - Add buffer to streaming queue
 * @buf: Video buffer
 *
 * In memory-to-memory mode, start streaming on the pipeline if buffers are
 * queued on both the input and the output, if the pipeline isn't already busy.
 * If the pipeline is busy, it will be restarted in the output module interrupt
 * handler.
 */
static void isp_video_buffer_queue(struct isp_video_buffer *buf)
{
	struct isp_video_fh *vfh = isp_video_queue_to_isp_video_fh(buf->queue);
	struct isp_buffer *buffer = to_isp_buffer(buf);
	struct isp_video *video = vfh->video;
	struct isp_pipeline *pipe = to_isp_pipeline(&video->video.entity);
	enum isp_pipeline_state state;
	unsigned long flags;
	unsigned int empty;
	unsigned int start;

	empty = list_empty(&video->dmaqueue);
	list_add_tail(&buffer->buffer.irqlist, &video->dmaqueue);

	if (empty) {
		if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
			state = ISP_PIPELINE_QUEUE_OUTPUT;
		else
			state = ISP_PIPELINE_QUEUE_INPUT;

		spin_lock_irqsave(&pipe->lock, flags);
		pipe->state |= state;
		video->ops->queue(video, buffer);
		video->dmaqueue_flags |= ISP_VIDEO_DMAQUEUE_QUEUED;

		start = isp_pipeline_ready(pipe);
		if (start)
			pipe->state |= ISP_PIPELINE_STREAM;
		spin_unlock_irqrestore(&pipe->lock, flags);

		if (start)
			omap3isp_pipeline_set_stream(pipe,
						ISP_PIPELINE_STREAM_SINGLESHOT);
	}
}

static const struct isp_video_queue_operations isp_video_queue_ops = {
	.queue_prepare = &isp_video_queue_prepare,
	.buffer_prepare = &isp_video_buffer_prepare,
	.buffer_queue = &isp_video_buffer_queue,
	.buffer_cleanup = &isp_video_buffer_cleanup,
};

/*
 * omap3isp_video_buffer_next - Complete the current buffer and return the next
 * @video: ISP video object
 *
 * Remove the current video buffer from the DMA queue and fill its timestamp,
 * field count and state fields before waking up its completion handler.
 *
 * For capture video nodes the buffer state is set to ISP_BUF_STATE_DONE if no
 * error has been flagged in the pipeline, or to ISP_BUF_STATE_ERROR otherwise.
 * For video output nodes the buffer state is always set to ISP_BUF_STATE_DONE.
 *
 * The DMA queue is expected to contain at least one buffer.
 *
 * Return a pointer to the next buffer in the DMA queue, or NULL if the queue is
 * empty.
 */
struct isp_buffer *omap3isp_video_buffer_next(struct isp_video *video)
{
	struct isp_pipeline *pipe = to_isp_pipeline(&video->video.entity);
	struct isp_video_queue *queue = video->queue;
	enum isp_pipeline_state state;
	struct isp_video_buffer *buf;
	unsigned long flags;
	struct timespec ts;

	spin_lock_irqsave(&queue->irqlock, flags);
	if (WARN_ON(list_empty(&video->dmaqueue))) {
		spin_unlock_irqrestore(&queue->irqlock, flags);
		return NULL;
	}

	buf = list_first_entry(&video->dmaqueue, struct isp_video_buffer,
			       irqlist);
	list_del(&buf->irqlist);
	spin_unlock_irqrestore(&queue->irqlock, flags);

	ktime_get_ts(&ts);
	buf->vbuf.timestamp.tv_sec = ts.tv_sec;
	buf->vbuf.timestamp.tv_usec = ts.tv_nsec / NSEC_PER_USEC;

	/* Do frame number propagation only if this is the output video node.
	 * Frame number either comes from the CSI receivers or it gets
	 * incremented here if H3A is not active.
	 * Note: There is no guarantee that the output buffer will finish
	 * first, so the input number might lag behind by 1 in some cases.
	 */
	if (video == pipe->output && !pipe->do_propagation)
		buf->vbuf.sequence = atomic_inc_return(&pipe->frame_number);
	else
		buf->vbuf.sequence = atomic_read(&pipe->frame_number);

	/* Report pipeline errors to userspace on the capture device side. */
	if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE && pipe->error) {
		buf->state = ISP_BUF_STATE_ERROR;
		pipe->error = false;
	} else {
		buf->state = ISP_BUF_STATE_DONE;
	}

	wake_up(&buf->wait);

	if (list_empty(&video->dmaqueue)) {
		if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
			state = ISP_PIPELINE_QUEUE_OUTPUT
			      | ISP_PIPELINE_STREAM;
		else
			state = ISP_PIPELINE_QUEUE_INPUT
			      | ISP_PIPELINE_STREAM;

		spin_lock_irqsave(&pipe->lock, flags);
		pipe->state &= ~state;
		if (video->pipe.stream_state == ISP_PIPELINE_STREAM_CONTINUOUS)
			video->dmaqueue_flags |= ISP_VIDEO_DMAQUEUE_UNDERRUN;
		spin_unlock_irqrestore(&pipe->lock, flags);
		return NULL;
	}

	if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE && pipe->input != NULL) {
		spin_lock_irqsave(&pipe->lock, flags);
		pipe->state &= ~ISP_PIPELINE_STREAM;
		spin_unlock_irqrestore(&pipe->lock, flags);
	}

	buf = list_first_entry(&video->dmaqueue, struct isp_video_buffer,
			       irqlist);
	buf->state = ISP_BUF_STATE_ACTIVE;
	return to_isp_buffer(buf);
}

/*
 * omap3isp_video_resume - Perform resume operation on the buffers
 * @video: ISP video object
 * @continuous: Pipeline is in single shot mode if 0 or continuous mode otherwise
 *
 * This function is intended to be used on suspend/resume scenario. It
 * requests video queue layer to discard buffers marked as DONE if it's in
 * continuous mode and requests ISP modules to queue again the ACTIVE buffer
 * if there's any.
 */
void omap3isp_video_resume(struct isp_video *video, int continuous)
{
	struct isp_buffer *buf = NULL;

	if (continuous && video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		omap3isp_video_queue_discard_done(video->queue);

	if (!list_empty(&video->dmaqueue)) {
		buf = list_first_entry(&video->dmaqueue,
				       struct isp_buffer, buffer.irqlist);
		video->ops->queue(video, buf);
		video->dmaqueue_flags |= ISP_VIDEO_DMAQUEUE_QUEUED;
	} else {
		if (continuous)
			video->dmaqueue_flags |= ISP_VIDEO_DMAQUEUE_UNDERRUN;
	}
}

/* -----------------------------------------------------------------------------
 * V4L2 ioctls
 */

static int
isp_video_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
{
	struct isp_video *video = video_drvdata(file);

	strlcpy(cap->driver, ISP_VIDEO_DRIVER_NAME, sizeof(cap->driver));
	strlcpy(cap->card, video->video.name, sizeof(cap->card));
	strlcpy(cap->bus_info, "media", sizeof(cap->bus_info));

	if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
	else
		cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;

	return 0;
}

static int
isp_video_get_format(struct file *file, void *fh, struct v4l2_format *format)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);

	if (format->type != video->type)
		return -EINVAL;

	mutex_lock(&video->mutex);
	*format = vfh->format;
	mutex_unlock(&video->mutex);

	return 0;
}

static int
isp_video_set_format(struct file *file, void *fh, struct v4l2_format *format)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);
	struct v4l2_mbus_framefmt fmt;

	if (format->type != video->type)
		return -EINVAL;

	mutex_lock(&video->mutex);

	/* Fill the bytesperline and sizeimage fields by converting to media bus
	 * format and back to pixel format.
	 */
	isp_video_pix_to_mbus(&format->fmt.pix, &fmt);
	isp_video_mbus_to_pix(video, &fmt, &format->fmt.pix);

	vfh->format = *format;

	mutex_unlock(&video->mutex);
	return 0;
}

static int
isp_video_try_format(struct file *file, void *fh, struct v4l2_format *format)
{
	struct isp_video *video = video_drvdata(file);
	struct v4l2_subdev_format fmt;
	struct v4l2_subdev *subdev;
	u32 pad;
	int ret;

	if (format->type != video->type)
		return -EINVAL;

	subdev = isp_video_remote_subdev(video, &pad);
	if (subdev == NULL)
		return -EINVAL;

	isp_video_pix_to_mbus(&format->fmt.pix, &fmt.format);

	fmt.pad = pad;
	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
	if (ret)
		return ret == -ENOIOCTLCMD ? -ENOTTY : ret;

	isp_video_mbus_to_pix(video, &fmt.format, &format->fmt.pix);
	return 0;
}

static int
isp_video_cropcap(struct file *file, void *fh, struct v4l2_cropcap *cropcap)
{
	struct isp_video *video = video_drvdata(file);
	struct v4l2_subdev *subdev;
	int ret;

	subdev = isp_video_remote_subdev(video, NULL);
	if (subdev == NULL)
		return -EINVAL;

	mutex_lock(&video->mutex);
	ret = v4l2_subdev_call(subdev, video, cropcap, cropcap);
	mutex_unlock(&video->mutex);

	return ret == -ENOIOCTLCMD ? -ENOTTY : ret;
}

static int
isp_video_get_crop(struct file *file, void *fh, struct v4l2_crop *crop)
{
	struct isp_video *video = video_drvdata(file);
	struct v4l2_subdev_format format;
	struct v4l2_subdev *subdev;
	u32 pad;
	int ret;

	subdev = isp_video_remote_subdev(video, &pad);
	if (subdev == NULL)
		return -EINVAL;

	/* Try the get crop operation first and fallback to get format if not
	 * implemented.
	 */
	ret = v4l2_subdev_call(subdev, video, g_crop, crop);
	if (ret != -ENOIOCTLCMD)
		return ret;

	format.pad = pad;
	format.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &format);
	if (ret < 0)
		return ret == -ENOIOCTLCMD ? -ENOTTY : ret;

	crop->c.left = 0;
	crop->c.top = 0;
	crop->c.width = format.format.width;
	crop->c.height = format.format.height;

	return 0;
}

static int
isp_video_set_crop(struct file *file, void *fh, const struct v4l2_crop *crop)
{
	struct isp_video *video = video_drvdata(file);
	struct v4l2_subdev *subdev;
	int ret;

	subdev = isp_video_remote_subdev(video, NULL);
	if (subdev == NULL)
		return -EINVAL;

	mutex_lock(&video->mutex);
	ret = v4l2_subdev_call(subdev, video, s_crop, crop);
	mutex_unlock(&video->mutex);

	return ret == -ENOIOCTLCMD ? -ENOTTY : ret;
}

static int
isp_video_get_param(struct file *file, void *fh, struct v4l2_streamparm *a)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);

	if (video->type != V4L2_BUF_TYPE_VIDEO_OUTPUT ||
	    video->type != a->type)
		return -EINVAL;

	memset(a, 0, sizeof(*a));
	a->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
	a->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
	a->parm.output.timeperframe = vfh->timeperframe;

	return 0;
}

static int
isp_video_set_param(struct file *file, void *fh, struct v4l2_streamparm *a)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);

	if (video->type != V4L2_BUF_TYPE_VIDEO_OUTPUT ||
	    video->type != a->type)
		return -EINVAL;

	if (a->parm.output.timeperframe.denominator == 0)
		a->parm.output.timeperframe.denominator = 1;

	vfh->timeperframe = a->parm.output.timeperframe;

	return 0;
}

static int
isp_video_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *rb)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);

	return omap3isp_video_queue_reqbufs(&vfh->queue, rb);
}

static int
isp_video_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);

	return omap3isp_video_queue_querybuf(&vfh->queue, b);
}

static int
isp_video_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);

	return omap3isp_video_queue_qbuf(&vfh->queue, b);
}

static int
isp_video_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);

	return omap3isp_video_queue_dqbuf(&vfh->queue, b,
					  file->f_flags & O_NONBLOCK);
}

static int isp_video_check_external_subdevs(struct isp_video *video,
					    struct isp_pipeline *pipe)
{
	struct isp_device *isp = video->isp;
	struct media_entity *ents[] = {
		&isp->isp_csi2a.subdev.entity,
		&isp->isp_csi2c.subdev.entity,
		&isp->isp_ccp2.subdev.entity,
		&isp->isp_ccdc.subdev.entity
	};
	struct media_pad *source_pad;
	struct media_entity *source = NULL;
	struct media_entity *sink;
	struct v4l2_subdev_format fmt;
	struct v4l2_ext_controls ctrls;
	struct v4l2_ext_control ctrl;
	unsigned int i;
	int ret = 0;

	for (i = 0; i < ARRAY_SIZE(ents); i++) {
		/* Is the entity part of the pipeline? */
		if (!(pipe->entities & (1 << ents[i]->id)))
			continue;

		/* ISP entities have always sink pad == 0. Find source. */
		source_pad = media_entity_remote_pad(&ents[i]->pads[0]);
		if (source_pad == NULL)
			continue;

		source = source_pad->entity;
		sink = ents[i];
		break;
	}

	if (!source) {
		dev_warn(isp->dev, "can't find source, failing now\n");
		return ret;
	}

	if (media_entity_type(source) != MEDIA_ENT_T_V4L2_SUBDEV)
		return 0;

	pipe->external = media_entity_to_v4l2_subdev(source);

	fmt.pad = source_pad->index;
	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	ret = v4l2_subdev_call(media_entity_to_v4l2_subdev(sink),
			       pad, get_fmt, NULL, &fmt);
	if (unlikely(ret < 0)) {
		dev_warn(isp->dev, "get_fmt returned null!\n");
		return ret;
	}

	pipe->external_width =
		omap3isp_video_format_info(fmt.format.code)->width;

	memset(&ctrls, 0, sizeof(ctrls));
	memset(&ctrl, 0, sizeof(ctrl));

	ctrl.id = V4L2_CID_PIXEL_RATE;

	ctrls.count = 1;
	ctrls.controls = &ctrl;

	ret = v4l2_g_ext_ctrls(pipe->external->ctrl_handler, &ctrls);
	if (ret < 0) {
		dev_warn(isp->dev, "no pixel rate control in subdev %s\n",
			 pipe->external->name);
		return ret;
	}

	pipe->external_rate = ctrl.value64;

	if (pipe->entities & (1 << isp->isp_ccdc.subdev.entity.id)) {
		unsigned int rate = UINT_MAX;
		/*
		 * Check that maximum allowed CCDC pixel rate isn't
		 * exceeded by the pixel rate.
		 */
		omap3isp_ccdc_max_rate(&isp->isp_ccdc, &rate);
		if (pipe->external_rate > rate)
			return -ENOSPC;
	}

	return 0;
}

/*
 * Stream management
 *
 * Every ISP pipeline has a single input and a single output. The input can be
 * either a sensor or a video node. The output is always a video node.
 *
 * As every pipeline has an output video node, the ISP video objects at the
 * pipeline output stores the pipeline state. It tracks the streaming state of
 * both the input and output, as well as the availability of buffers.
 *
 * In sensor-to-memory mode, frames are always available at the pipeline input.
 * Starting the sensor usually requires I2C transfers and must be done in
 * interruptible context. The pipeline is started and stopped synchronously
 * to the stream on/off commands. All modules in the pipeline will get their
 * subdev set stream handler called. The module at the end of the pipeline must
 * delay starting the hardware until buffers are available at its output.
 *
 * In memory-to-memory mode, starting/stopping the stream requires
 * synchronization between the input and output. ISP modules can't be stopped
 * in the middle of a frame, and at least some of the modules seem to become
 * busy as soon as they're started, even if they don't receive a frame start
 * event. For that reason frames need to be processed in single-shot mode. The
 * driver needs to wait until a frame is completely processed and written to
 * memory before restarting the pipeline for the next frame. Pipelined
 * processing might be possible but requires more testing.
 *
 * Stream start must be delayed until buffers are available at both the input
 * and output. The pipeline must be started in the videobuf queue callback with
 * the buffers queue spinlock held. The modules subdev set stream operation must
 * not sleep.
 */
static int
isp_video_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);
	enum isp_pipeline_state state;
	struct isp_pipeline *pipe;
	unsigned long flags;
	int ret;

	if (type != video->type)
		return -EINVAL;

	mutex_lock(&video->stream_lock);

	if (video->streaming) {
		mutex_unlock(&video->stream_lock);
		return -EBUSY;
	}

	/* Start streaming on the pipeline. No link touching an entity in the
	 * pipeline can be activated or deactivated once streaming is started.
	 */
	pipe = video->video.entity.pipe
	     ? to_isp_pipeline(&video->video.entity) : &video->pipe;

	pipe->entities = 0;

	if (video->isp->pdata->set_constraints)
		video->isp->pdata->set_constraints(video->isp, true);
	pipe->l3_ick = clk_get_rate(video->isp->clock[ISP_CLK_L3_ICK]);
	pipe->max_rate = pipe->l3_ick;

	ret = media_entity_pipeline_start(&video->video.entity, &pipe->pipe);
	if (ret < 0)
		goto err_pipeline_start;

	/* Verify that the currently configured format matches the output of
	 * the connected subdev.
	 */
	ret = isp_video_check_format(video, vfh);
	if (ret < 0)
		goto err_check_format;

	video->bpl_padding = ret;
	video->bpl_value = vfh->format.fmt.pix.bytesperline;

	ret = isp_video_get_graph_data(video, pipe);
	if (ret < 0)
		goto err_check_format;

	if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		state = ISP_PIPELINE_STREAM_OUTPUT | ISP_PIPELINE_IDLE_OUTPUT;
	else
		state = ISP_PIPELINE_STREAM_INPUT | ISP_PIPELINE_IDLE_INPUT;

	ret = isp_video_check_external_subdevs(video, pipe);
	if (ret < 0)
		goto err_check_format;

	/* Validate the pipeline and update its state. */
	ret = isp_video_validate_pipeline(pipe);
	if (ret < 0)
		goto err_check_format;

	pipe->error = false;

	spin_lock_irqsave(&pipe->lock, flags);
	pipe->state &= ~ISP_PIPELINE_STREAM;
	pipe->state |= state;
	spin_unlock_irqrestore(&pipe->lock, flags);

	/* Set the maximum time per frame as the value requested by userspace.
	 * This is a soft limit that can be overridden if the hardware doesn't
	 * support the request limit.
	 */
	if (video->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
		pipe->max_timeperframe = vfh->timeperframe;

	video->queue = &vfh->queue;
	INIT_LIST_HEAD(&video->dmaqueue);
	atomic_set(&pipe->frame_number, -1);

	ret = omap3isp_video_queue_streamon(&vfh->queue);
	if (ret < 0)
		goto err_check_format;

	/* In sensor-to-memory mode, the stream can be started synchronously
	 * to the stream on command. In memory-to-memory mode, it will be
	 * started when buffers are queued on both the input and output.
	 */
	if (pipe->input == NULL) {
		ret = omap3isp_pipeline_set_stream(pipe,
					      ISP_PIPELINE_STREAM_CONTINUOUS);
		if (ret < 0)
			goto err_set_stream;
		spin_lock_irqsave(&video->queue->irqlock, flags);
		if (list_empty(&video->dmaqueue))
			video->dmaqueue_flags |= ISP_VIDEO_DMAQUEUE_UNDERRUN;
		spin_unlock_irqrestore(&video->queue->irqlock, flags);
	}

	video->streaming = 1;

	mutex_unlock(&video->stream_lock);
	return 0;

err_set_stream:
	omap3isp_video_queue_streamoff(&vfh->queue);
err_check_format:
	media_entity_pipeline_stop(&video->video.entity);
err_pipeline_start:
	if (video->isp->pdata->set_constraints)
		video->isp->pdata->set_constraints(video->isp, false);
	/* The DMA queue must be emptied here, otherwise CCDC interrupts that
	 * will get triggered the next time the CCDC is powered up will try to
	 * access buffers that might have been freed but still present in the
	 * DMA queue. This can easily get triggered if the above
	 * omap3isp_pipeline_set_stream() call fails on a system with a
	 * free-running sensor.
	 */
	INIT_LIST_HEAD(&video->dmaqueue);
	video->queue = NULL;

	mutex_unlock(&video->stream_lock);
	return ret;
}

static int
isp_video_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
{
	struct isp_video_fh *vfh = to_isp_video_fh(fh);
	struct isp_video *video = video_drvdata(file);
	struct isp_pipeline *pipe = to_isp_pipeline(&video->video.entity);
	enum isp_pipeline_state state;
	unsigned int streaming;
	unsigned long flags;

	if (type != video->type)
		return -EINVAL;

	mutex_lock(&video->stream_lock);

	/* Make sure we're not streaming yet. */
	mutex_lock(&vfh->queue.lock);
	streaming = vfh->queue.streaming;
	mutex_unlock(&vfh->queue.lock);

	if (!streaming)
		goto done;

	/* Update the pipeline state. */
	if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		state = ISP_PIPELINE_STREAM_OUTPUT
		      | ISP_PIPELINE_QUEUE_OUTPUT;
	else
		state = ISP_PIPELINE_STREAM_INPUT
		      | ISP_PIPELINE_QUEUE_INPUT;

	spin_lock_irqsave(&pipe->lock, flags);
	pipe->state &= ~state;
	spin_unlock_irqrestore(&pipe->lock, flags);

	/* Stop the stream. */
	omap3isp_pipeline_set_stream(pipe, ISP_PIPELINE_STREAM_STOPPED);
	omap3isp_video_queue_streamoff(&vfh->queue);
	video->queue = NULL;
	video->streaming = 0;

	if (video->isp->pdata->set_constraints)
		video->isp->pdata->set_constraints(video->isp, false);
	media_entity_pipeline_stop(&video->video.entity);

done:
	mutex_unlock(&video->stream_lock);
	return 0;
}

static int
isp_video_enum_input(struct file *file, void *fh, struct v4l2_input *input)
{
	if (input->index > 0)
		return -EINVAL;

	strlcpy(input->name, "camera", sizeof(input->name));
	input->type = V4L2_INPUT_TYPE_CAMERA;

	return 0;
}

static int
isp_video_g_input(struct file *file, void *fh, unsigned int *input)
{
	*input = 0;

	return 0;
}

static int
isp_video_s_input(struct file *file, void *fh, unsigned int input)
{
	return input == 0 ? 0 : -EINVAL;
}

static const struct v4l2_ioctl_ops isp_video_ioctl_ops = {
	.vidioc_querycap		= isp_video_querycap,
	.vidioc_g_fmt_vid_cap		= isp_video_get_format,
	.vidioc_s_fmt_vid_cap		= isp_video_set_format,
	.vidioc_try_fmt_vid_cap		= isp_video_try_format,
	.vidioc_g_fmt_vid_out		= isp_video_get_format,
	.vidioc_s_fmt_vid_out		= isp_video_set_format,
	.vidioc_try_fmt_vid_out		= isp_video_try_format,
	.vidioc_cropcap			= isp_video_cropcap,
	.vidioc_g_crop			= isp_video_get_crop,
	.vidioc_s_crop			= isp_video_set_crop,
	.vidioc_g_parm			= isp_video_get_param,
	.vidioc_s_parm			= isp_video_set_param,
	.vidioc_reqbufs			= isp_video_reqbufs,
	.vidioc_querybuf		= isp_video_querybuf,
	.vidioc_qbuf			= isp_video_qbuf,
	.vidioc_dqbuf			= isp_video_dqbuf,
	.vidioc_streamon		= isp_video_streamon,
	.vidioc_streamoff		= isp_video_streamoff,
	.vidioc_enum_input		= isp_video_enum_input,
	.vidioc_g_input			= isp_video_g_input,
	.vidioc_s_input			= isp_video_s_input,
};

/* -----------------------------------------------------------------------------
 * V4L2 file operations
 */

static int isp_video_open(struct file *file)
{
	struct isp_video *video = video_drvdata(file);
	struct isp_video_fh *handle;
	int ret = 0;

	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
	if (handle == NULL)
		return -ENOMEM;

	v4l2_fh_init(&handle->vfh, &video->video);
	v4l2_fh_add(&handle->vfh);

	/* If this is the first user, initialise the pipeline. */
	if (omap3isp_get(video->isp) == NULL) {
		ret = -EBUSY;
		goto done;
	}

	ret = omap3isp_pipeline_pm_use(&video->video.entity, 1);
	if (ret < 0) {
		omap3isp_put(video->isp);
		goto done;
	}

	omap3isp_video_queue_init(&handle->queue, video->type,
				  &isp_video_queue_ops, video->isp->dev,
				  sizeof(struct isp_buffer));

	memset(&handle->format, 0, sizeof(handle->format));
	handle->format.type = video->type;
	handle->timeperframe.denominator = 1;

	handle->video = video;
	file->private_data = &handle->vfh;

done:
	if (ret < 0) {
		v4l2_fh_del(&handle->vfh);
		kfree(handle);
	}

	return ret;
}

static int isp_video_release(struct file *file)
{
	struct isp_video *video = video_drvdata(file);
	struct v4l2_fh *vfh = file->private_data;
	struct isp_video_fh *handle = to_isp_video_fh(vfh);

	/* Disable streaming and free the buffers queue resources. */
	isp_video_streamoff(file, vfh, video->type);

	mutex_lock(&handle->queue.lock);
	omap3isp_video_queue_cleanup(&handle->queue);
	mutex_unlock(&handle->queue.lock);

	omap3isp_pipeline_pm_use(&video->video.entity, 0);

	/* Release the file handle. */
	v4l2_fh_del(vfh);
	kfree(handle);
	file->private_data = NULL;

	omap3isp_put(video->isp);

	return 0;
}

static unsigned int isp_video_poll(struct file *file, poll_table *wait)
{
	struct isp_video_fh *vfh = to_isp_video_fh(file->private_data);
	struct isp_video_queue *queue = &vfh->queue;

	return omap3isp_video_queue_poll(queue, file, wait);
}

static int isp_video_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct isp_video_fh *vfh = to_isp_video_fh(file->private_data);

	return omap3isp_video_queue_mmap(&vfh->queue, vma);
}

static struct v4l2_file_operations isp_video_fops = {
	.owner = THIS_MODULE,
	.unlocked_ioctl = video_ioctl2,
	.open = isp_video_open,
	.release = isp_video_release,
	.poll = isp_video_poll,
	.mmap = isp_video_mmap,
};

/* -----------------------------------------------------------------------------
 * ISP video core
 */

static const struct isp_video_operations isp_video_dummy_ops = {
};

int omap3isp_video_init(struct isp_video *video, const char *name)
{
	const char *direction;
	int ret;

	switch (video->type) {
	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
		direction = "output";
		video->pad.flags = MEDIA_PAD_FL_SINK;
		break;
	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
		direction = "input";
		video->pad.flags = MEDIA_PAD_FL_SOURCE;
		video->video.vfl_dir = VFL_DIR_TX;
		break;

	default:
		return -EINVAL;
	}

	ret = media_entity_init(&video->video.entity, 1, &video->pad, 0);
	if (ret < 0)
		return ret;

	mutex_init(&video->mutex);
	atomic_set(&video->active, 0);

	spin_lock_init(&video->pipe.lock);
	mutex_init(&video->stream_lock);

	/* Initialize the video device. */
	if (video->ops == NULL)
		video->ops = &isp_video_dummy_ops;

	video->video.fops = &isp_video_fops;
	snprintf(video->video.name, sizeof(video->video.name),
		 "OMAP3 ISP %s %s", name, direction);
	video->video.vfl_type = VFL_TYPE_GRABBER;
	video->video.release = video_device_release_empty;
	video->video.ioctl_ops = &isp_video_ioctl_ops;
	video->pipe.stream_state = ISP_PIPELINE_STREAM_STOPPED;

	video_set_drvdata(&video->video, video);

	return 0;
}

void omap3isp_video_cleanup(struct isp_video *video)
{
	media_entity_cleanup(&video->video.entity);
	mutex_destroy(&video->stream_lock);
	mutex_destroy(&video->mutex);
}

int omap3isp_video_register(struct isp_video *video, struct v4l2_device *vdev)
{
	int ret;

	video->video.v4l2_dev = vdev;

	ret = video_register_device(&video->video, VFL_TYPE_GRABBER, -1);
	if (ret < 0)
		dev_err(video->isp->dev,
			"%s: could not register video device (%d)\n",
			__func__, ret);

	return ret;
}

void omap3isp_video_unregister(struct isp_video *video)
{
	if (video_is_registered(&video->video))
		video_unregister_device(&video->video);
}