// SPDX-License-Identifier: GPL-2.0
/*
 * 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.
 *
 * 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);
                v4l2_fh_del(&handle->vfh);
                v4l2_fh_exit(&handle->vfh);
                kfree(handle);
                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 __poll_t 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");

        cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
                            V4L2_CAP_STREAMING | V4L2_CAP_DEVICE_CAPS;
        strscpy(cap->driver, CAPTURE_DRV_NAME, sizeof(cap->driver));
        strscpy(cap->bus_info, "VPFE", sizeof(cap->bus_info));
        strscpy(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");

        /* 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,
        .wait_prepare           = vb2_ops_wait_prepare,
        .wait_finish            = vb2_ops_wait_finish,
};

/*
 * 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;
        q->lock = &video->lock;

        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,
                        video->video_dev.v4l2_dev->mdev, 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;
        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;
        }
        /* 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 */
        mutex_init(&video->lock);
        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;
        video->video_dev.lock = &video->lock;
        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);
        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;

        if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
                video->video_dev.device_caps = V4L2_CAP_VIDEO_CAPTURE;
        else
                video->video_dev.device_caps = V4L2_CAP_VIDEO_OUTPUT;
        video->video_dev.device_caps |= V4L2_CAP_STREAMING;
        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);
        }
}