/*
 * Copyright (C) 2012 Texas Instruments Inc
 *
 * 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 version 2.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 * Contributors:
 *      Manjunath Hadli <manjunath.hadli@ti.com>
 *      Prabhakar Lad <prabhakar.lad@ti.com>
 */

#include <linux/module.h>
#include <linux/slab.h>

#include <media/v4l2-ioctl.h>

#include "vpfe.h"
#include "vpfe_mc_capture.h"

static int debug;

/* get v4l2 subdev pointer to external subdev which is active */
static struct media_entity *vpfe_get_input_entity
			(struct vpfe_video_device *video)
{
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct media_pad *remote;

	remote = media_entity_remote_pad(&vpfe_dev->vpfe_isif.pads[0]);
	if (!remote) {
		pr_err("Invalid media connection to isif/ccdc\n");
		return NULL;
	}
	return remote->entity;
}

/* updates external subdev(sensor/decoder) which is active */
static int vpfe_update_current_ext_subdev(struct vpfe_video_device *video)
{
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_config *vpfe_cfg;
	struct v4l2_subdev *subdev;
	struct media_pad *remote;
	int i;

	remote = media_entity_remote_pad(&vpfe_dev->vpfe_isif.pads[0]);
	if (!remote) {
		pr_err("Invalid media connection to isif/ccdc\n");
		return -EINVAL;
	}

	subdev = media_entity_to_v4l2_subdev(remote->entity);
	vpfe_cfg = vpfe_dev->pdev->platform_data;
	for (i = 0; i < vpfe_cfg->num_subdevs; i++) {
		if (!strcmp(vpfe_cfg->sub_devs[i].module_name, subdev->name)) {
			video->current_ext_subdev = &vpfe_cfg->sub_devs[i];
			break;
		}
	}

	/* if user not linked decoder/sensor to isif/ccdc */
	if (i == vpfe_cfg->num_subdevs) {
		pr_err("Invalid media chain connection to isif/ccdc\n");
		return -EINVAL;
	}
	/* find the v4l2 subdev pointer */
	for (i = 0; i < vpfe_dev->num_ext_subdevs; i++) {
		if (!strcmp(video->current_ext_subdev->module_name,
			vpfe_dev->sd[i]->name))
			video->current_ext_subdev->subdev = vpfe_dev->sd[i];
	}
	return 0;
}

/* get the subdev which is connected to the output video node */
static struct v4l2_subdev *
vpfe_video_remote_subdev(struct vpfe_video_device *video, u32 *pad)
{
	struct media_pad *remote = media_entity_remote_pad(&video->pad);

	if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
		return NULL;
	if (pad)
		*pad = remote->index;
	return media_entity_to_v4l2_subdev(remote->entity);
}

/* get the format set at output pad of the adjacent subdev */
static int
__vpfe_video_get_format(struct vpfe_video_device *video,
			struct v4l2_format *format)
{
	struct v4l2_subdev_format fmt;
	struct v4l2_subdev *subdev;
	struct media_pad *remote;
	u32 pad;
	int ret;

	subdev = vpfe_video_remote_subdev(video, &pad);
	if (!subdev)
		return -EINVAL;

	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	remote = media_entity_remote_pad(&video->pad);
	fmt.pad = remote->index;

	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
	if (ret == -ENOIOCTLCMD)
		return -EINVAL;

	format->type = video->type;
	/* convert mbus_format to v4l2_format */
	v4l2_fill_pix_format(&format->fmt.pix, &fmt.format);
	mbus_to_pix(&fmt.format, &format->fmt.pix);

	return 0;
}

/* make a note of pipeline details */
static int vpfe_prepare_pipeline(struct vpfe_video_device *video)
{
	struct media_graph graph;
	struct media_entity *entity = &video->video_dev.entity;
	struct media_device *mdev = entity->graph_obj.mdev;
	struct vpfe_pipeline *pipe = &video->pipe;
	struct vpfe_video_device *far_end = NULL;
	int ret;

	pipe->input_num = 0;
	pipe->output_num = 0;

	if (video->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
		pipe->inputs[pipe->input_num++] = video;
	else
		pipe->outputs[pipe->output_num++] = video;

	mutex_lock(&mdev->graph_mutex);
	ret = media_graph_walk_init(&graph, mdev);
	if (ret) {
		mutex_unlock(&mdev->graph_mutex);
		return -ENOMEM;
	}
	media_graph_walk_start(&graph, entity);
	while ((entity = media_graph_walk_next(&graph))) {
		if (entity == &video->video_dev.entity)
			continue;
		if (!is_media_entity_v4l2_video_device(entity))
			continue;
		far_end = to_vpfe_video(media_entity_to_video_device(entity));
		if (far_end->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
			pipe->inputs[pipe->input_num++] = far_end;
		else
			pipe->outputs[pipe->output_num++] = far_end;
	}
	media_graph_walk_cleanup(&graph);
	mutex_unlock(&mdev->graph_mutex);

	return 0;
}

/* update pipe state selected by user */
static int vpfe_update_pipe_state(struct vpfe_video_device *video)
{
	struct vpfe_pipeline *pipe = &video->pipe;
	int ret;

	ret = vpfe_prepare_pipeline(video);
	if (ret)
		return ret;

	/*
	 * Find out if there is any input video
	 * if yes, it is single shot.
	 */
	if (pipe->input_num == 0) {
		pipe->state = VPFE_PIPELINE_STREAM_CONTINUOUS;
		ret = vpfe_update_current_ext_subdev(video);
		if (ret) {
			pr_err("Invalid external subdev\n");
			return ret;
		}
	} else {
		pipe->state = VPFE_PIPELINE_STREAM_SINGLESHOT;
	}
	video->initialized = 1;
	video->skip_frame_count = 1;
	video->skip_frame_count_init = 1;
	return 0;
}

/* checks whether pipeline is ready for enabling */
int vpfe_video_is_pipe_ready(struct vpfe_pipeline *pipe)
{
	int i;

	for (i = 0; i < pipe->input_num; i++)
		if (!pipe->inputs[i]->started ||
			pipe->inputs[i]->state != VPFE_VIDEO_BUFFER_QUEUED)
			return 0;
	for (i = 0; i < pipe->output_num; i++)
		if (!pipe->outputs[i]->started ||
			pipe->outputs[i]->state != VPFE_VIDEO_BUFFER_QUEUED)
			return 0;
	return 1;
}

/**
 * Validate a pipeline by checking both ends of all links for format
 * discrepancies.
 *
 * Return 0 if all formats match, or -EPIPE if at least one link is found with
 * different formats on its two ends.
 */
static int vpfe_video_validate_pipeline(struct vpfe_pipeline *pipe)
{
	struct v4l2_subdev_format fmt_source;
	struct v4l2_subdev_format fmt_sink;
	struct v4l2_subdev *subdev;
	struct media_pad *pad;
	int ret;

	/*
	 * Should not matter if it is output[0] or 1 as
	 * the general ideas is to traverse backwards and
	 * the fact that the out video node always has the
	 * format of the connected pad.
	 */
	subdev = vpfe_video_remote_subdev(pipe->outputs[0], NULL);
	if (!subdev)
		return -EPIPE;

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

		fmt_sink.which = V4L2_SUBDEV_FORMAT_ACTIVE;
		fmt_sink.pad = pad->index;
		ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL,
				       &fmt_sink);

		if (ret < 0 && ret != -ENOIOCTLCMD)
			return -EPIPE;

		/* Retrieve the source format */
		pad = media_entity_remote_pad(pad);
		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
			break;

		subdev = media_entity_to_v4l2_subdev(pad->entity);

		fmt_source.which = V4L2_SUBDEV_FORMAT_ACTIVE;
		fmt_source.pad = pad->index;
		ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt_source);
		if (ret < 0 && ret != -ENOIOCTLCMD)
			return -EPIPE;

		/* Check if the two ends match */
		if (fmt_source.format.code != fmt_sink.format.code ||
		    fmt_source.format.width != fmt_sink.format.width ||
		    fmt_source.format.height != fmt_sink.format.height)
			return -EPIPE;
	}
	return 0;
}

/*
 * vpfe_pipeline_enable() - Enable streaming on a pipeline
 * @vpfe_dev: vpfe device
 * @pipe: vpfe pipeline
 *
 * Walk the entities chain starting at the pipeline output video node and start
 * all modules in the chain in the given mode.
 *
 * Return 0 if successful, or the return value of the failed video::s_stream
 * operation otherwise.
 */
static int vpfe_pipeline_enable(struct vpfe_pipeline *pipe)
{
	struct media_entity *entity;
	struct v4l2_subdev *subdev;
	struct media_device *mdev;
	int ret;

	if (pipe->state == VPFE_PIPELINE_STREAM_CONTINUOUS)
		entity = vpfe_get_input_entity(pipe->outputs[0]);
	else
		entity = &pipe->inputs[0]->video_dev.entity;

	mdev = entity->graph_obj.mdev;
	mutex_lock(&mdev->graph_mutex);
	ret = media_graph_walk_init(&pipe->graph, mdev);
	if (ret)
		goto out;
	media_graph_walk_start(&pipe->graph, entity);
	while ((entity = media_graph_walk_next(&pipe->graph))) {

		if (!is_media_entity_v4l2_subdev(entity))
			continue;
		subdev = media_entity_to_v4l2_subdev(entity);
		ret = v4l2_subdev_call(subdev, video, s_stream, 1);
		if (ret < 0 && ret != -ENOIOCTLCMD)
			break;
	}
out:
	if (ret)
		media_graph_walk_cleanup(&pipe->graph);
	mutex_unlock(&mdev->graph_mutex);
	return ret;
}

/*
 * vpfe_pipeline_disable() - Disable streaming on a pipeline
 * @vpfe_dev: vpfe device
 * @pipe: VPFE pipeline
 *
 * Walk the entities chain starting at the pipeline output video node and stop
 * all modules in the chain.
 *
 * Return 0 if all modules have been properly stopped, or -ETIMEDOUT if a module
 * can't be stopped.
 */
static int vpfe_pipeline_disable(struct vpfe_pipeline *pipe)
{
	struct media_entity *entity;
	struct v4l2_subdev *subdev;
	struct media_device *mdev;
	int ret = 0;

	if (pipe->state == VPFE_PIPELINE_STREAM_CONTINUOUS)
		entity = vpfe_get_input_entity(pipe->outputs[0]);
	else
		entity = &pipe->inputs[0]->video_dev.entity;

	mdev = entity->graph_obj.mdev;
	mutex_lock(&mdev->graph_mutex);
	media_graph_walk_start(&pipe->graph, entity);

	while ((entity = media_graph_walk_next(&pipe->graph))) {

		if (!is_media_entity_v4l2_subdev(entity))
			continue;
		subdev = media_entity_to_v4l2_subdev(entity);
		ret = v4l2_subdev_call(subdev, video, s_stream, 0);
		if (ret < 0 && ret != -ENOIOCTLCMD)
			break;
	}
	mutex_unlock(&mdev->graph_mutex);

	media_graph_walk_cleanup(&pipe->graph);
	return ret ? -ETIMEDOUT : 0;
}

/*
 * vpfe_pipeline_set_stream() - Enable/disable streaming on a pipeline
 * @vpfe_dev: VPFE device
 * @pipe: VPFE pipeline
 * @state: Stream state (stopped or active)
 *
 * Set the pipeline to the given stream state.
 *
 * Return 0 if successful, or the return value of the failed video::s_stream
 * operation otherwise.
 */
static int vpfe_pipeline_set_stream(struct vpfe_pipeline *pipe,
			    enum vpfe_pipeline_stream_state state)
{
	if (state == VPFE_PIPELINE_STREAM_STOPPED)
		return vpfe_pipeline_disable(pipe);

	return vpfe_pipeline_enable(pipe);
}

static int all_videos_stopped(struct vpfe_video_device *video)
{
	struct vpfe_pipeline *pipe = &video->pipe;
	int i;

	for (i = 0; i < pipe->input_num; i++)
		if (pipe->inputs[i]->started)
			return 0;
	for (i = 0; i < pipe->output_num; i++)
		if (pipe->outputs[i]->started)
			return 0;
	return 1;
}

/*
 * vpfe_open() - open video device
 * @file: file pointer
 *
 * initialize media pipeline state, allocate memory for file handle
 *
 * Return 0 if successful, or the return -ENODEV otherwise.
 */
static int vpfe_open(struct file *file)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_fh *handle;

	/* Allocate memory for the file handle object */
	handle = kzalloc(sizeof(struct vpfe_fh), GFP_KERNEL);

	if (!handle)
		return -ENOMEM;

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

	mutex_lock(&video->lock);
	/* If decoder is not initialized. initialize it */
	if (!video->initialized && vpfe_update_pipe_state(video)) {
		mutex_unlock(&video->lock);
		return -ENODEV;
	}
	/* Increment device users counter */
	video->usrs++;
	/* Set io_allowed member to false */
	handle->io_allowed = 0;
	handle->video = video;
	file->private_data = &handle->vfh;
	mutex_unlock(&video->lock);

	return 0;
}

/* get the next buffer available from dma queue */
static unsigned long
vpfe_video_get_next_buffer(struct vpfe_video_device *video)
{
	video->cur_frm = video->next_frm =
		list_entry(video->dma_queue.next,
			   struct vpfe_cap_buffer, list);

	list_del(&video->next_frm->list);
	video->next_frm->vb.vb2_buf.state = VB2_BUF_STATE_ACTIVE;
	return vb2_dma_contig_plane_dma_addr(&video->next_frm->vb.vb2_buf, 0);
}

/* schedule the next buffer which is available on dma queue */
void vpfe_video_schedule_next_buffer(struct vpfe_video_device *video)
{
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	unsigned long addr;

	if (list_empty(&video->dma_queue))
		return;

	video->next_frm = list_entry(video->dma_queue.next,
					struct vpfe_cap_buffer, list);

	if (video->pipe.state == VPFE_PIPELINE_STREAM_SINGLESHOT)
		video->cur_frm = video->next_frm;

	list_del(&video->next_frm->list);
	video->next_frm->vb.vb2_buf.state = VB2_BUF_STATE_ACTIVE;
	addr = vb2_dma_contig_plane_dma_addr(&video->next_frm->vb.vb2_buf, 0);
	video->ops->queue(vpfe_dev, addr);
	video->state = VPFE_VIDEO_BUFFER_QUEUED;
}

/* schedule the buffer for capturing bottom field */
void vpfe_video_schedule_bottom_field(struct vpfe_video_device *video)
{
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	unsigned long addr;

	addr = vb2_dma_contig_plane_dma_addr(&video->cur_frm->vb.vb2_buf, 0);
	addr += video->field_off;
	video->ops->queue(vpfe_dev, addr);
}

/* make buffer available for dequeue */
void vpfe_video_process_buffer_complete(struct vpfe_video_device *video)
{
	struct vpfe_pipeline *pipe = &video->pipe;

	video->cur_frm->vb.vb2_buf.timestamp = ktime_get_ns();
	vb2_buffer_done(&video->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
	if (pipe->state == VPFE_PIPELINE_STREAM_CONTINUOUS)
		video->cur_frm = video->next_frm;
}

/* vpfe_stop_capture() - stop streaming */
static void vpfe_stop_capture(struct vpfe_video_device *video)
{
	struct vpfe_pipeline *pipe = &video->pipe;

	video->started = 0;

	if (video->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
		return;
	if (all_videos_stopped(video))
		vpfe_pipeline_set_stream(pipe,
					 VPFE_PIPELINE_STREAM_STOPPED);
}

/*
 * vpfe_release() - release video device
 * @file: file pointer
 *
 * deletes buffer queue, frees the buffers and the vpfe file handle
 *
 * Return 0
 */
static int vpfe_release(struct file *file)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct v4l2_fh *vfh = file->private_data;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_fh *fh = container_of(vfh, struct vpfe_fh, vfh);

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_release\n");

	/* Get the device lock */
	mutex_lock(&video->lock);
	/* if this instance is doing IO */
	if (fh->io_allowed) {
		if (video->started) {
			vpfe_stop_capture(video);
			/*
			 * mark pipe state as stopped in vpfe_release(),
			 * as app might call streamon() after streamoff()
			 * in which case driver has to start streaming.
			 */
			video->pipe.state = VPFE_PIPELINE_STREAM_STOPPED;
			vb2_streamoff(&video->buffer_queue,
				      video->buffer_queue.type);
		}
		video->io_usrs = 0;
		/* Free buffers allocated */
		vb2_queue_release(&video->buffer_queue);
	}
	/* Decrement device users counter */
	video->usrs--;
	v4l2_fh_del(&fh->vfh);
	v4l2_fh_exit(&fh->vfh);
	/* If this is the last file handle */
	if (!video->usrs)
		video->initialized = 0;
	mutex_unlock(&video->lock);
	file->private_data = NULL;
	/* Free memory allocated to file handle object */
	v4l2_fh_del(vfh);
	kzfree(fh);
	return 0;
}

/*
 * vpfe_mmap() - It is used to map kernel space buffers
 * into user spaces
 */
static int vpfe_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_mmap\n");
	return vb2_mmap(&video->buffer_queue, vma);
}

/*
 * vpfe_poll() - It is used for select/poll system call
 */
static unsigned int vpfe_poll(struct file *file, poll_table *wait)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_poll\n");
	if (video->started)
		return vb2_poll(&video->buffer_queue, file, wait);
	return 0;
}

/* vpfe capture driver file operations */
static const struct v4l2_file_operations vpfe_fops = {
	.owner = THIS_MODULE,
	.open = vpfe_open,
	.release = vpfe_release,
	.unlocked_ioctl = video_ioctl2,
	.mmap = vpfe_mmap,
	.poll = vpfe_poll
};

/*
 * vpfe_querycap() - query capabilities of video device
 * @file: file pointer
 * @priv: void pointer
 * @cap: pointer to v4l2_capability structure
 *
 * fills v4l2 capabilities structure
 *
 * Return 0
 */
static int vpfe_querycap(struct file *file, void  *priv,
			       struct v4l2_capability *cap)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_querycap\n");

	if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
		cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
	else
		cap->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
	cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
			    V4L2_CAP_STREAMING | V4L2_CAP_DEVICE_CAPS;
	strlcpy(cap->driver, CAPTURE_DRV_NAME, sizeof(cap->driver));
	strlcpy(cap->bus_info, "VPFE", sizeof(cap->bus_info));
	strlcpy(cap->card, vpfe_dev->cfg->card_name, sizeof(cap->card));

	return 0;
}

/*
 * vpfe_g_fmt() - get the format which is active on video device
 * @file: file pointer
 * @priv: void pointer
 * @fmt: pointer to v4l2_format structure
 *
 * fills v4l2 format structure with active format
 *
 * Return 0
 */
static int vpfe_g_fmt(struct file *file, void *priv,
				struct v4l2_format *fmt)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_g_fmt\n");
	/* Fill in the information about format */
	*fmt = video->fmt;
	return 0;
}

/*
 * vpfe_enum_fmt() - enum formats supported on media chain
 * @file: file pointer
 * @priv: void pointer
 * @fmt: pointer to v4l2_fmtdesc structure
 *
 * fills v4l2_fmtdesc structure with output format set on adjacent subdev,
 * only one format is enumearted as subdevs are already configured
 *
 * Return 0 if successful, error code otherwise
 */
static int vpfe_enum_fmt(struct file *file, void  *priv,
				   struct v4l2_fmtdesc *fmt)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_subdev_format sd_fmt;
	struct v4l2_mbus_framefmt mbus;
	struct v4l2_subdev *subdev;
	struct v4l2_format format;
	struct media_pad *remote;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_enum_fmt\n");

	/*
	 * since already subdev pad format is set,
	 * only one pixel format is available
	 */
	if (fmt->index > 0) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid index\n");
		return -EINVAL;
	}
	/* get the remote pad */
	remote = media_entity_remote_pad(&video->pad);
	if (!remote) {
		v4l2_err(&vpfe_dev->v4l2_dev,
			 "invalid remote pad for video node\n");
		return -EINVAL;
	}
	/* get the remote subdev */
	subdev = vpfe_video_remote_subdev(video, NULL);
	if (!subdev) {
		v4l2_err(&vpfe_dev->v4l2_dev,
			 "invalid remote subdev for video node\n");
		return -EINVAL;
	}
	sd_fmt.pad = remote->index;
	sd_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	/* get output format of remote subdev */
	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &sd_fmt);
	if (ret) {
		v4l2_err(&vpfe_dev->v4l2_dev,
			 "invalid remote subdev for video node\n");
		return ret;
	}
	/* convert to pix format */
	mbus.code = sd_fmt.format.code;
	mbus_to_pix(&mbus, &format.fmt.pix);
	/* copy the result */
	fmt->pixelformat = format.fmt.pix.pixelformat;

	return 0;
}

/*
 * vpfe_s_fmt() - set the format on video device
 * @file: file pointer
 * @priv: void pointer
 * @fmt: pointer to v4l2_format structure
 *
 * validate and set the format on video device
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_s_fmt(struct file *file, void *priv,
				struct v4l2_format *fmt)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_format format;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_s_fmt\n");
	/* If streaming is started, return error */
	if (video->started) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Streaming is started\n");
		return -EBUSY;
	}
	/* get adjacent subdev's output pad format */
	ret = __vpfe_video_get_format(video, &format);
	if (ret)
		return ret;
	*fmt = format;
	video->fmt = *fmt;
	return 0;
}

/*
 * vpfe_try_fmt() - try the format on video device
 * @file: file pointer
 * @priv: void pointer
 * @fmt: pointer to v4l2_format structure
 *
 * validate the format, update with correct format
 * based on output format set on adjacent subdev
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_try_fmt(struct file *file, void *priv,
				  struct v4l2_format *fmt)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_format format;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_try_fmt\n");
	/* get adjacent subdev's output pad format */
	ret = __vpfe_video_get_format(video, &format);
	if (ret)
		return ret;

	*fmt = format;
	return 0;
}

/*
 * vpfe_enum_input() - enum inputs supported on media chain
 * @file: file pointer
 * @priv: void pointer
 * @fmt: pointer to v4l2_fmtdesc structure
 *
 * fills v4l2_input structure with input available on media chain,
 * only one input is enumearted as media chain is setup by this time
 *
 * Return 0 if successful, -EINVAL is media chain is invalid
 */
static int vpfe_enum_input(struct file *file, void *priv,
				 struct v4l2_input *inp)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_ext_subdev_info *sdinfo = video->current_ext_subdev;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_enum_input\n");
	/* enumerate from the subdev user has chosen through mc */
	if (inp->index < sdinfo->num_inputs) {
		memcpy(inp, &sdinfo->inputs[inp->index],
		       sizeof(struct v4l2_input));
		return 0;
	}
	return -EINVAL;
}

/*
 * vpfe_g_input() - get index of the input which is active
 * @file: file pointer
 * @priv: void pointer
 * @index: pointer to unsigned int
 *
 * set index with input index which is active
 */
static int vpfe_g_input(struct file *file, void *priv, unsigned int *index)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_g_input\n");

	*index = video->current_input;
	return 0;
}

/*
 * vpfe_s_input() - set input which is pointed by input index
 * @file: file pointer
 * @priv: void pointer
 * @index: pointer to unsigned int
 *
 * set input on external subdev
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_s_input(struct file *file, void *priv, unsigned int index)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_ext_subdev_info *sdinfo;
	struct vpfe_route *route;
	struct v4l2_input *inps;
	u32 output;
	u32 input;
	int ret;
	int i;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_s_input\n");

	ret = mutex_lock_interruptible(&video->lock);
	if (ret)
		return ret;
	/*
	 * If streaming is started return device busy
	 * error
	 */
	if (video->started) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Streaming is on\n");
		ret = -EBUSY;
		goto unlock_out;
	}

	sdinfo = video->current_ext_subdev;
	if (!sdinfo->registered) {
		ret = -EINVAL;
		goto unlock_out;
	}
	if (vpfe_dev->cfg->setup_input &&
		vpfe_dev->cfg->setup_input(sdinfo->grp_id) < 0) {
		ret = -EFAULT;
		v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
			  "couldn't setup input for %s\n",
			  sdinfo->module_name);
		goto unlock_out;
	}
	route = &sdinfo->routes[index];
	if (route && sdinfo->can_route) {
		input = route->input;
		output = route->output;
		ret = v4l2_device_call_until_err(&vpfe_dev->v4l2_dev,
						 sdinfo->grp_id, video,
						 s_routing, input, output, 0);
		if (ret) {
			v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
				"s_input:error in setting input in decoder\n");
			ret = -EINVAL;
			goto unlock_out;
		}
	}
	/* set standards set by subdev in video device */
	for (i = 0; i < sdinfo->num_inputs; i++) {
		inps = &sdinfo->inputs[i];
		video->video_dev.tvnorms |= inps->std;
	}
	video->current_input = index;
unlock_out:
	mutex_unlock(&video->lock);
	return ret;
}

/*
 * vpfe_querystd() - query std which is being input on external subdev
 * @file: file pointer
 * @priv: void pointer
 * @std_id: pointer to v4l2_std_id structure
 *
 * call external subdev through v4l2_device_call_until_err to
 * get the std that is being active.
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_querystd(struct file *file, void *priv, v4l2_std_id *std_id)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_ext_subdev_info *sdinfo;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_querystd\n");

	ret = mutex_lock_interruptible(&video->lock);
	sdinfo = video->current_ext_subdev;
	if (ret)
		return ret;
	/* Call querystd function of decoder device */
	ret = v4l2_device_call_until_err(&vpfe_dev->v4l2_dev, sdinfo->grp_id,
					 video, querystd, std_id);
	mutex_unlock(&video->lock);
	return ret;
}

/*
 * vpfe_s_std() - set std on external subdev
 * @file: file pointer
 * @priv: void pointer
 * @std_id: pointer to v4l2_std_id structure
 *
 * set std pointed by std_id on external subdev by calling it using
 * v4l2_device_call_until_err
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_s_std(struct file *file, void *priv, v4l2_std_id std_id)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_ext_subdev_info *sdinfo;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_s_std\n");

	/* Call decoder driver function to set the standard */
	ret = mutex_lock_interruptible(&video->lock);
	if (ret)
		return ret;
	sdinfo = video->current_ext_subdev;
	/* If streaming is started, return device busy error */
	if (video->started) {
		v4l2_err(&vpfe_dev->v4l2_dev, "streaming is started\n");
		ret = -EBUSY;
		goto unlock_out;
	}
	ret = v4l2_device_call_until_err(&vpfe_dev->v4l2_dev, sdinfo->grp_id,
					 video, s_std, std_id);
	if (ret < 0) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Failed to set standard\n");
		video->stdid = V4L2_STD_UNKNOWN;
		goto unlock_out;
	}
	video->stdid = std_id;
unlock_out:
	mutex_unlock(&video->lock);
	return ret;
}

static int vpfe_g_std(struct file *file, void *priv, v4l2_std_id *tvnorm)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_g_std\n");
	*tvnorm = video->stdid;
	return 0;
}

/*
 * vpfe_enum_dv_timings() - enumerate dv_timings which are supported by
 *			to external subdev
 * @file: file pointer
 * @priv: void pointer
 * @timings: pointer to v4l2_enum_dv_timings structure
 *
 * enum dv_timings's which are supported by external subdev through
 * v4l2_subdev_call
 *
 * Return 0 on success, error code otherwise
 */
static int
vpfe_enum_dv_timings(struct file *file, void *fh,
		  struct v4l2_enum_dv_timings *timings)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_subdev *subdev = video->current_ext_subdev->subdev;

	timings->pad = 0;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_enum_dv_timings\n");
	return v4l2_subdev_call(subdev, pad, enum_dv_timings, timings);
}

/*
 * vpfe_query_dv_timings() - query the dv_timings which is being input
 *			to external subdev
 * @file: file pointer
 * @priv: void pointer
 * @timings: pointer to v4l2_dv_timings structure
 *
 * get dv_timings which is being input on external subdev through
 * v4l2_subdev_call
 *
 * Return 0 on success, error code otherwise
 */
static int
vpfe_query_dv_timings(struct file *file, void *fh,
		   struct v4l2_dv_timings *timings)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_subdev *subdev = video->current_ext_subdev->subdev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_query_dv_timings\n");
	return v4l2_subdev_call(subdev, video, query_dv_timings, timings);
}

/*
 * vpfe_s_dv_timings() - set dv_timings on external subdev
 * @file: file pointer
 * @priv: void pointer
 * @timings: pointer to v4l2_dv_timings structure
 *
 * set dv_timings pointed by timings on external subdev through
 * v4l2_device_call_until_err, this configures amplifier also
 *
 * Return 0 on success, error code otherwise
 */
static int
vpfe_s_dv_timings(struct file *file, void *fh,
		  struct v4l2_dv_timings *timings)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_s_dv_timings\n");

	video->stdid = V4L2_STD_UNKNOWN;
	return v4l2_device_call_until_err(&vpfe_dev->v4l2_dev,
					  video->current_ext_subdev->grp_id,
					  video, s_dv_timings, timings);
}

/*
 * vpfe_g_dv_timings() - get dv_timings which is set on external subdev
 * @file: file pointer
 * @priv: void pointer
 * @timings: pointer to v4l2_dv_timings structure
 *
 * get dv_timings which is set on external subdev through
 * v4l2_subdev_call
 *
 * Return 0 on success, error code otherwise
 */
static int
vpfe_g_dv_timings(struct file *file, void *fh,
	      struct v4l2_dv_timings *timings)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct v4l2_subdev *subdev = video->current_ext_subdev->subdev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_g_dv_timings\n");
	return v4l2_subdev_call(subdev, video, g_dv_timings, timings);
}

/*
 *  Videobuf operations
 */
/*
 * vpfe_buffer_queue_setup : Callback function for buffer setup.
 * @vq: vb2_queue ptr
 * @fmt: v4l2 format
 * @nbuffers: ptr to number of buffers requested by application
 * @nplanes:: contains number of distinct video planes needed to hold a frame
 * @sizes[]: contains the size (in bytes) of each plane.
 * @alloc_devs: ptr to allocation context
 *
 * This callback function is called when reqbuf() is called to adjust
 * the buffer nbuffers and buffer size
 */
static int
vpfe_buffer_queue_setup(struct vb2_queue *vq,
			unsigned int *nbuffers, unsigned int *nplanes,
			unsigned int sizes[], struct device *alloc_devs[])
{
	struct vpfe_fh *fh = vb2_get_drv_priv(vq);
	struct vpfe_video_device *video = fh->video;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	unsigned long size;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_buffer_queue_setup\n");
	size = video->fmt.fmt.pix.sizeimage;

	if (vq->num_buffers + *nbuffers < 3)
		*nbuffers = 3 - vq->num_buffers;

	*nplanes = 1;
	sizes[0] = size;
	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev,
		 "nbuffers=%d, size=%lu\n", *nbuffers, size);
	return 0;
}

/*
 * vpfe_buffer_prepare : callback function for buffer prepare
 * @vb: ptr to vb2_buffer
 *
 * This is the callback function for buffer prepare when vb2_qbuf()
 * function is called. The buffer is prepared and user space virtual address
 * or user address is converted into  physical address
 */
static int vpfe_buffer_prepare(struct vb2_buffer *vb)
{
	struct vpfe_fh *fh = vb2_get_drv_priv(vb->vb2_queue);
	struct vpfe_video_device *video = fh->video;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	unsigned long addr;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_buffer_prepare\n");

	if (vb->state != VB2_BUF_STATE_ACTIVE &&
	    vb->state != VB2_BUF_STATE_PREPARED)
		return 0;

	/* Initialize buffer */
	vb2_set_plane_payload(vb, 0, video->fmt.fmt.pix.sizeimage);
	if (vb2_plane_vaddr(vb, 0) &&
	    vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0))
		return -EINVAL;

	addr = vb2_dma_contig_plane_dma_addr(vb, 0);
	/* Make sure user addresses are aligned to 32 bytes */
	if (!ALIGN(addr, 32))
		return -EINVAL;

	return 0;
}

static void vpfe_buffer_queue(struct vb2_buffer *vb)
{
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	/* Get the file handle object and device object */
	struct vpfe_fh *fh = vb2_get_drv_priv(vb->vb2_queue);
	struct vpfe_video_device *video = fh->video;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_pipeline *pipe = &video->pipe;
	struct vpfe_cap_buffer *buf = container_of(vbuf,
				struct vpfe_cap_buffer, vb);
	unsigned long flags;
	unsigned long empty;
	unsigned long addr;

	spin_lock_irqsave(&video->dma_queue_lock, flags);
	empty = list_empty(&video->dma_queue);
	/* add the buffer to the DMA queue */
	list_add_tail(&buf->list, &video->dma_queue);
	spin_unlock_irqrestore(&video->dma_queue_lock, flags);
	/* this case happens in case of single shot */
	if (empty && video->started && pipe->state ==
		VPFE_PIPELINE_STREAM_SINGLESHOT &&
		video->state == VPFE_VIDEO_BUFFER_NOT_QUEUED) {
		spin_lock(&video->dma_queue_lock);
		addr = vpfe_video_get_next_buffer(video);
		video->ops->queue(vpfe_dev, addr);

		video->state = VPFE_VIDEO_BUFFER_QUEUED;
		spin_unlock(&video->dma_queue_lock);

		/* enable h/w each time in single shot */
		if (vpfe_video_is_pipe_ready(pipe))
			vpfe_pipeline_set_stream(pipe,
					VPFE_PIPELINE_STREAM_SINGLESHOT);
	}
}

/* vpfe_start_capture() - start streaming on all the subdevs */
static int vpfe_start_capture(struct vpfe_video_device *video)
{
	struct vpfe_pipeline *pipe = &video->pipe;
	int ret = 0;

	video->started = 1;
	if (vpfe_video_is_pipe_ready(pipe))
		ret = vpfe_pipeline_set_stream(pipe, pipe->state);

	return ret;
}

static int vpfe_start_streaming(struct vb2_queue *vq, unsigned int count)
{
	struct vpfe_fh *fh = vb2_get_drv_priv(vq);
	struct vpfe_video_device *video = fh->video;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	unsigned long addr;
	int ret;

	ret = mutex_lock_interruptible(&video->lock);
	if (ret)
		goto streamoff;

	/* Get the next frame from the buffer queue */
	video->cur_frm = video->next_frm =
		list_entry(video->dma_queue.next, struct vpfe_cap_buffer, list);
	/* Remove buffer from the buffer queue */
	list_del(&video->cur_frm->list);
	/* Mark state of the current frame to active */
	video->cur_frm->vb.vb2_buf.state = VB2_BUF_STATE_ACTIVE;
	/* Initialize field_id and started member */
	video->field_id = 0;
	addr = vb2_dma_contig_plane_dma_addr(&video->cur_frm->vb.vb2_buf, 0);
	video->ops->queue(vpfe_dev, addr);
	video->state = VPFE_VIDEO_BUFFER_QUEUED;

	ret = vpfe_start_capture(video);
	if (ret) {
		struct vpfe_cap_buffer *buf, *tmp;

		vb2_buffer_done(&video->cur_frm->vb.vb2_buf,
				VB2_BUF_STATE_QUEUED);
		list_for_each_entry_safe(buf, tmp, &video->dma_queue, list) {
			list_del(&buf->list);
			vb2_buffer_done(&buf->vb.vb2_buf,
					VB2_BUF_STATE_QUEUED);
		}
		goto unlock_out;
	}

	mutex_unlock(&video->lock);

	return ret;
unlock_out:
	mutex_unlock(&video->lock);
streamoff:
	ret = vb2_streamoff(&video->buffer_queue, video->buffer_queue.type);
	return 0;
}

static int vpfe_buffer_init(struct vb2_buffer *vb)
{
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct vpfe_cap_buffer *buf = container_of(vbuf,
						   struct vpfe_cap_buffer, vb);

	INIT_LIST_HEAD(&buf->list);
	return 0;
}

/* abort streaming and wait for last buffer */
static void vpfe_stop_streaming(struct vb2_queue *vq)
{
	struct vpfe_fh *fh = vb2_get_drv_priv(vq);
	struct vpfe_video_device *video = fh->video;

	/* release all active buffers */
	if (video->cur_frm == video->next_frm) {
		vb2_buffer_done(&video->cur_frm->vb.vb2_buf,
				VB2_BUF_STATE_ERROR);
	} else {
		if (video->cur_frm != NULL)
			vb2_buffer_done(&video->cur_frm->vb.vb2_buf,
					VB2_BUF_STATE_ERROR);
		if (video->next_frm != NULL)
			vb2_buffer_done(&video->next_frm->vb.vb2_buf,
					VB2_BUF_STATE_ERROR);
	}

	while (!list_empty(&video->dma_queue)) {
		video->next_frm = list_entry(video->dma_queue.next,
						struct vpfe_cap_buffer, list);
		list_del(&video->next_frm->list);
		vb2_buffer_done(&video->next_frm->vb.vb2_buf,
				VB2_BUF_STATE_ERROR);
	}
}

static void vpfe_buf_cleanup(struct vb2_buffer *vb)
{
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct vpfe_fh *fh = vb2_get_drv_priv(vb->vb2_queue);
	struct vpfe_video_device *video = fh->video;
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_cap_buffer *buf = container_of(vbuf,
					struct vpfe_cap_buffer, vb);

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_buf_cleanup\n");
	if (vb->state == VB2_BUF_STATE_ACTIVE)
		list_del_init(&buf->list);
}

static const struct vb2_ops video_qops = {
	.queue_setup		= vpfe_buffer_queue_setup,
	.buf_init		= vpfe_buffer_init,
	.buf_prepare		= vpfe_buffer_prepare,
	.start_streaming	= vpfe_start_streaming,
	.stop_streaming		= vpfe_stop_streaming,
	.buf_cleanup		= vpfe_buf_cleanup,
	.buf_queue		= vpfe_buffer_queue,
};

/*
 * vpfe_reqbufs() - supported REQBUF only once opening
 * the device.
 */
static int vpfe_reqbufs(struct file *file, void *priv,
			struct v4l2_requestbuffers *req_buf)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_fh *fh = file->private_data;
	struct vb2_queue *q;
	int ret;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_reqbufs\n");

	if (req_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    req_buf->type != V4L2_BUF_TYPE_VIDEO_OUTPUT){
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid buffer type\n");
		return -EINVAL;
	}

	ret = mutex_lock_interruptible(&video->lock);
	if (ret)
		return ret;

	if (video->io_usrs != 0) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Only one IO user allowed\n");
		ret = -EBUSY;
		goto unlock_out;
	}
	video->memory = req_buf->memory;

	/* Initialize videobuf2 queue as per the buffer type */
	q = &video->buffer_queue;
	q->type = req_buf->type;
	q->io_modes = VB2_MMAP | VB2_USERPTR;
	q->drv_priv = fh;
	q->min_buffers_needed = 1;
	q->ops = &video_qops;
	q->mem_ops = &vb2_dma_contig_memops;
	q->buf_struct_size = sizeof(struct vpfe_cap_buffer);
	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
	q->dev = vpfe_dev->pdev;

	ret = vb2_queue_init(q);
	if (ret) {
		v4l2_err(&vpfe_dev->v4l2_dev, "vb2_queue_init() failed\n");
		goto unlock_out;
	}

	fh->io_allowed = 1;
	video->io_usrs = 1;
	INIT_LIST_HEAD(&video->dma_queue);
	ret = vb2_reqbufs(&video->buffer_queue, req_buf);

unlock_out:
	mutex_unlock(&video->lock);
	return ret;
}

/*
 * vpfe_querybuf() - query buffers for exchange
 */
static int vpfe_querybuf(struct file *file, void *priv,
			 struct v4l2_buffer *buf)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_querybuf\n");

	if (buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    buf->type != V4L2_BUF_TYPE_VIDEO_OUTPUT) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid buf type\n");
		return  -EINVAL;
	}

	if (video->memory != V4L2_MEMORY_MMAP) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid memory\n");
		return -EINVAL;
	}

	/* Call vb2_querybuf to get information */
	return vb2_querybuf(&video->buffer_queue, buf);
}

/*
 * vpfe_qbuf() - queue buffers for capture or processing
 */
static int vpfe_qbuf(struct file *file, void *priv,
		     struct v4l2_buffer *p)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_fh *fh = file->private_data;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_qbuf\n");

	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    p->type != V4L2_BUF_TYPE_VIDEO_OUTPUT) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid buf type\n");
		return -EINVAL;
	}
	/*
	 * If this file handle is not allowed to do IO,
	 * return error
	 */
	if (!fh->io_allowed) {
		v4l2_err(&vpfe_dev->v4l2_dev, "fh->io_allowed\n");
		return -EACCES;
	}

	return vb2_qbuf(&video->buffer_queue, p);
}

/*
 * vpfe_dqbuf() - deque buffer which is done with processing
 */
static int vpfe_dqbuf(struct file *file, void *priv,
		      struct v4l2_buffer *buf)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_dqbuf\n");

	if (buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    buf->type != V4L2_BUF_TYPE_VIDEO_OUTPUT) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid buf type\n");
		return -EINVAL;
	}

	return vb2_dqbuf(&video->buffer_queue,
			 buf, (file->f_flags & O_NONBLOCK));
}

/*
 * vpfe_streamon() - start streaming
 * @file: file pointer
 * @priv: void pointer
 * @buf_type: enum v4l2_buf_type
 *
 * queue buffer onto hardware for capture/processing and
 * start all the subdevs which are in media chain
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_streamon(struct file *file, void *priv,
			 enum v4l2_buf_type buf_type)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_pipeline *pipe = &video->pipe;
	struct vpfe_fh *fh = file->private_data;
	struct vpfe_ext_subdev_info *sdinfo;
	int ret = -EINVAL;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_streamon\n");

	if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    buf_type != V4L2_BUF_TYPE_VIDEO_OUTPUT) {
		v4l2_err(&vpfe_dev->v4l2_dev, "Invalid buf type\n");
		return ret;
	}
	/* If file handle is not allowed IO, return error */
	if (!fh->io_allowed) {
		v4l2_err(&vpfe_dev->v4l2_dev, "fh->io_allowed\n");
		return -EACCES;
	}
	sdinfo = video->current_ext_subdev;
	/* If buffer queue is empty, return error */
	if (list_empty(&video->buffer_queue.queued_list)) {
		v4l2_err(&vpfe_dev->v4l2_dev, "buffer queue is empty\n");
		return -EIO;
	}
	/* Validate the pipeline */
	if (buf_type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
		ret = vpfe_video_validate_pipeline(pipe);
		if (ret < 0)
			return ret;
	}
	/* Call vb2_streamon to start streaming */
	return vb2_streamon(&video->buffer_queue, buf_type);
}

/*
 * vpfe_streamoff() - stop streaming
 * @file: file pointer
 * @priv: void pointer
 * @buf_type: enum v4l2_buf_type
 *
 * stop all the subdevs which are in media chain
 *
 * Return 0 on success, error code otherwise
 */
static int vpfe_streamoff(struct file *file, void *priv,
			  enum v4l2_buf_type buf_type)
{
	struct vpfe_video_device *video = video_drvdata(file);
	struct vpfe_device *vpfe_dev = video->vpfe_dev;
	struct vpfe_fh *fh = file->private_data;
	int ret = 0;

	v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "vpfe_streamoff\n");

	if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
	    buf_type != V4L2_BUF_TYPE_VIDEO_OUTPUT) {
		v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "Invalid buf type\n");
		return -EINVAL;
	}

	/* If io is allowed for this file handle, return error */
	if (!fh->io_allowed) {
		v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, "fh->io_allowed\n");
		return -EACCES;
	}

	/* If streaming is not started, return error */
	if (!video->started) {
		v4l2_err(&vpfe_dev->v4l2_dev, "device is not started\n");
		return -EINVAL;
	}

	ret = mutex_lock_interruptible(&video->lock);
	if (ret)
		return ret;

	vpfe_stop_capture(video);
	ret = vb2_streamoff(&video->buffer_queue, buf_type);
	mutex_unlock(&video->lock);

	return ret;
}

/* vpfe capture ioctl operations */
static const struct v4l2_ioctl_ops vpfe_ioctl_ops = {
	.vidioc_querycap	 = vpfe_querycap,
	.vidioc_g_fmt_vid_cap    = vpfe_g_fmt,
	.vidioc_s_fmt_vid_cap    = vpfe_s_fmt,
	.vidioc_try_fmt_vid_cap  = vpfe_try_fmt,
	.vidioc_enum_fmt_vid_cap = vpfe_enum_fmt,
	.vidioc_g_fmt_vid_out    = vpfe_g_fmt,
	.vidioc_s_fmt_vid_out    = vpfe_s_fmt,
	.vidioc_try_fmt_vid_out  = vpfe_try_fmt,
	.vidioc_enum_fmt_vid_out = vpfe_enum_fmt,
	.vidioc_enum_input	 = vpfe_enum_input,
	.vidioc_g_input		 = vpfe_g_input,
	.vidioc_s_input		 = vpfe_s_input,
	.vidioc_querystd	 = vpfe_querystd,
	.vidioc_s_std		 = vpfe_s_std,
	.vidioc_g_std		 = vpfe_g_std,
	.vidioc_enum_dv_timings	 = vpfe_enum_dv_timings,
	.vidioc_query_dv_timings = vpfe_query_dv_timings,
	.vidioc_s_dv_timings	 = vpfe_s_dv_timings,
	.vidioc_g_dv_timings	 = vpfe_g_dv_timings,
	.vidioc_reqbufs		 = vpfe_reqbufs,
	.vidioc_querybuf	 = vpfe_querybuf,
	.vidioc_qbuf		 = vpfe_qbuf,
	.vidioc_dqbuf		 = vpfe_dqbuf,
	.vidioc_streamon	 = vpfe_streamon,
	.vidioc_streamoff	 = vpfe_streamoff,
};

/* VPFE video init function */
int vpfe_video_init(struct vpfe_video_device *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;
		video->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		break;

	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
		direction = "input";
		video->pad.flags = MEDIA_PAD_FL_SOURCE;
		video->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
		break;

	default:
		return -EINVAL;
	}
	/* Initialize field of video device */
	video->video_dev.release = video_device_release;
	video->video_dev.fops = &vpfe_fops;
	video->video_dev.ioctl_ops = &vpfe_ioctl_ops;
	video->video_dev.minor = -1;
	video->video_dev.tvnorms = 0;
	snprintf(video->video_dev.name, sizeof(video->video_dev.name),
		 "DAVINCI VIDEO %s %s", name, direction);

	spin_lock_init(&video->irqlock);
	spin_lock_init(&video->dma_queue_lock);
	mutex_init(&video->lock);
	ret = media_entity_pads_init(&video->video_dev.entity,
				1, &video->pad);
	if (ret < 0)
		return ret;

	video_set_drvdata(&video->video_dev, video);

	return 0;
}

/* vpfe video device register function */
int vpfe_video_register(struct vpfe_video_device *video,
			struct v4l2_device *vdev)
{
	int ret;

	video->video_dev.v4l2_dev = vdev;

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

/* vpfe video device unregister function */
void vpfe_video_unregister(struct vpfe_video_device *video)
{
	if (video_is_registered(&video->video_dev)) {
		video_unregister_device(&video->video_dev);
		media_entity_cleanup(&video->video_dev.entity);
	}
}