mixer_video.c

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/*
 * Samsung TV Mixer driver
 *
 * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
 *
 * Tomasz Stanislawski, <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation. either version 2 of the License,
 * or (at your option) any later version
 */

#define pr_fmt(fmt) "s5p-tv (mixer): " fmt

#include "mixer.h"

#include <media/v4l2-ioctl.h>
#include <linux/videodev2.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/timer.h>
#include <media/videobuf2-dma-contig.h>

static int find_reg_callback(struct device *dev, void *p)
{
    struct v4l2_subdev **sd = p;

    *sd = dev_get_drvdata(dev);
    /* non-zero value stops iteration */
    return 1;
}

static struct v4l2_subdev *find_and_register_subdev(
    struct mxr_device *mdev, char *module_name)
{
    struct device_driver *drv;
    struct v4l2_subdev *sd = NULL;
    int ret;

    /* TODO: add waiting until probe is finished */
    drv = driver_find(module_name, &platform_bus_type);
    if (!drv) {
        mxr_warn(mdev, "module %s is missing\n", module_name);
        return NULL;
    }
    /* driver refcnt is increased, it is safe to iterate over devices */
    ret = driver_for_each_device(drv, NULL, &sd, find_reg_callback);
    /* ret == 0 means that find_reg_callback was never executed */
    if (sd == NULL) {
        mxr_warn(mdev, "module %s provides no subdev!\n", module_name);
        goto done;
    }
    /* v4l2_device_register_subdev detects if sd is NULL */
    ret = v4l2_device_register_subdev(&mdev->v4l2_dev, sd);
    if (ret) {
        mxr_warn(mdev, "failed to register subdev %s\n", sd->name);
        sd = NULL;
    }

done:
    return sd;
}

int __devinit mxr_acquire_video(struct mxr_device *mdev,
    struct mxr_output_conf *output_conf, int output_count)
{
    struct device *dev = mdev->dev;
    struct v4l2_device *v4l2_dev = &mdev->v4l2_dev;
    int i;
    int ret = 0;
    struct v4l2_subdev *sd;

    strlcpy(v4l2_dev->name, dev_name(mdev->dev), sizeof(v4l2_dev->name));
    /* prepare context for V4L2 device */
    ret = v4l2_device_register(dev, v4l2_dev);
    if (ret) {
        mxr_err(mdev, "could not register v4l2 device.\n");
        goto fail;
    }

    mdev->alloc_ctx = vb2_dma_contig_init_ctx(mdev->dev);
    if (IS_ERR_OR_NULL(mdev->alloc_ctx)) {
        mxr_err(mdev, "could not acquire vb2 allocator\n");
        goto fail_v4l2_dev;
    }

    /* registering outputs */
    mdev->output_cnt = 0;
    for (i = 0; i < output_count; ++i) {
        struct mxr_output_conf *conf = &output_conf[i];
        struct mxr_output *out;

        sd = find_and_register_subdev(mdev, conf->module_name);
        /* trying to register next output */
        if (sd == NULL)
            continue;
        out = kzalloc(sizeof *out, GFP_KERNEL);
        if (out == NULL) {
            mxr_err(mdev, "no memory for '%s'\n",
                conf->output_name);
            ret = -ENOMEM;
            /* registered subdevs are removed in fail_v4l2_dev */
            goto fail_output;
        }
        strlcpy(out->name, conf->output_name, sizeof(out->name));
        out->sd = sd;
        out->cookie = conf->cookie;
        mdev->output[mdev->output_cnt++] = out;
        mxr_info(mdev, "added output '%s' from module '%s'\n",
            conf->output_name, conf->module_name);
        /* checking if maximal number of outputs is reached */
        if (mdev->output_cnt >= MXR_MAX_OUTPUTS)
            break;
    }

    if (mdev->output_cnt == 0) {
        mxr_err(mdev, "failed to register any output\n");
        ret = -ENODEV;
        /* skipping fail_output because there is nothing to free */
        goto fail_vb2_allocator;
    }

    return 0;

fail_output:
    /* kfree is NULL-safe */
    for (i = 0; i < mdev->output_cnt; ++i)
        kfree(mdev->output[i]);
    memset(mdev->output, 0, sizeof mdev->output);

fail_vb2_allocator:
    /* freeing allocator context */
    vb2_dma_contig_cleanup_ctx(mdev->alloc_ctx);

fail_v4l2_dev:
    /* NOTE: automatically unregister all subdevs */
    v4l2_device_unregister(v4l2_dev);

fail:
    return ret;
}

void mxr_release_video(struct mxr_device *mdev)
{
    int i;

    /* kfree is NULL-safe */
    for (i = 0; i < mdev->output_cnt; ++i)
        kfree(mdev->output[i]);

    vb2_dma_contig_cleanup_ctx(mdev->alloc_ctx);
    v4l2_device_unregister(&mdev->v4l2_dev);
}

static int mxr_querycap(struct file *file, void *priv,
    struct v4l2_capability *cap)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);

    strlcpy(cap->driver, MXR_DRIVER_NAME, sizeof cap->driver);
    strlcpy(cap->card, layer->vfd.name, sizeof cap->card);
    sprintf(cap->bus_info, "%d", layer->idx);
    cap->device_caps = V4L2_CAP_STREAMING | V4L2_CAP_VIDEO_OUTPUT_MPLANE;
    cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;

    return 0;
}

static void mxr_geometry_dump(struct mxr_device *mdev, struct mxr_geometry *geo)
{
    mxr_dbg(mdev, "src.full_size = (%u, %u)\n",
        geo->src.full_width, geo->src.full_height);
    mxr_dbg(mdev, "src.size = (%u, %u)\n",
        geo->src.width, geo->src.height);
    mxr_dbg(mdev, "src.offset = (%u, %u)\n",
        geo->src.x_offset, geo->src.y_offset);
    mxr_dbg(mdev, "dst.full_size = (%u, %u)\n",
        geo->dst.full_width, geo->dst.full_height);
    mxr_dbg(mdev, "dst.size = (%u, %u)\n",
        geo->dst.width, geo->dst.height);
    mxr_dbg(mdev, "dst.offset = (%u, %u)\n",
        geo->dst.x_offset, geo->dst.y_offset);
    mxr_dbg(mdev, "ratio = (%u, %u)\n",
        geo->x_ratio, geo->y_ratio);
}

static void mxr_layer_default_geo(struct mxr_layer *layer)
{
    struct mxr_device *mdev = layer->mdev;
    struct v4l2_mbus_framefmt mbus_fmt;

    memset(&layer->geo, 0, sizeof layer->geo);

    mxr_get_mbus_fmt(mdev, &mbus_fmt);

    layer->geo.dst.full_width = mbus_fmt.width;
    layer->geo.dst.full_height = mbus_fmt.height;
    layer->geo.dst.width = layer->geo.dst.full_width;
    layer->geo.dst.height = layer->geo.dst.full_height;
    layer->geo.dst.field = mbus_fmt.field;

    layer->geo.src.full_width = mbus_fmt.width;
    layer->geo.src.full_height = mbus_fmt.height;
    layer->geo.src.width = layer->geo.src.full_width;
    layer->geo.src.height = layer->geo.src.full_height;

    mxr_geometry_dump(mdev, &layer->geo);
    layer->ops.fix_geometry(layer, MXR_GEOMETRY_SINK, 0);
    mxr_geometry_dump(mdev, &layer->geo);
}

static void mxr_layer_update_output(struct mxr_layer *layer)
{
    struct mxr_device *mdev = layer->mdev;
    struct v4l2_mbus_framefmt mbus_fmt;

    mxr_get_mbus_fmt(mdev, &mbus_fmt);
    /* checking if update is needed */
    if (layer->geo.dst.full_width == mbus_fmt.width &&
        layer->geo.dst.full_height == mbus_fmt.width)
        return;

    layer->geo.dst.full_width = mbus_fmt.width;
    layer->geo.dst.full_height = mbus_fmt.height;
    layer->geo.dst.field = mbus_fmt.field;
    layer->ops.fix_geometry(layer, MXR_GEOMETRY_SINK, 0);

    mxr_geometry_dump(mdev, &layer->geo);
}

static const struct mxr_format *find_format_by_fourcc(
    struct mxr_layer *layer, unsigned long fourcc);
static const struct mxr_format *find_format_by_index(
    struct mxr_layer *layer, unsigned long index);

static int mxr_enum_fmt(struct file *file, void  *priv,
    struct v4l2_fmtdesc *f)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    const struct mxr_format *fmt;

    mxr_dbg(mdev, "%s\n", __func__);
    fmt = find_format_by_index(layer, f->index);
    if (fmt == NULL)
        return -EINVAL;

    strlcpy(f->description, fmt->name, sizeof(f->description));
    f->pixelformat = fmt->fourcc;

    return 0;
}

static unsigned int divup(unsigned int divident, unsigned int divisor)
{
    return (divident + divisor - 1) / divisor;
}

unsigned long mxr_get_plane_size(const struct mxr_block *blk,
    unsigned int width, unsigned int height)
{
    unsigned int bl_width = divup(width, blk->width);
    unsigned int bl_height = divup(height, blk->height);

    return bl_width * bl_height * blk->size;
}

static void mxr_mplane_fill(struct v4l2_plane_pix_format *planes,
    const struct mxr_format *fmt, u32 width, u32 height)
{
    int i;

    /* checking if nothing to fill */
    if (!planes)
        return;

    memset(planes, 0, sizeof(*planes) * fmt->num_subframes);
    for (i = 0; i < fmt->num_planes; ++i) {
        struct v4l2_plane_pix_format *plane = planes
            + fmt->plane2subframe[i];
        const struct mxr_block *blk = &fmt->plane[i];
        u32 bl_width = divup(width, blk->width);
        u32 bl_height = divup(height, blk->height);
        u32 sizeimage = bl_width * bl_height * blk->size;
        u16 bytesperline = bl_width * blk->size / blk->height;

        plane->sizeimage += sizeimage;
        plane->bytesperline = max(plane->bytesperline, bytesperline);
    }
}

static int mxr_g_fmt(struct file *file, void *priv,
                 struct v4l2_format *f)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct v4l2_pix_format_mplane *pix = &f->fmt.pix_mp;

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);

    pix->width = layer->geo.src.full_width;
    pix->height = layer->geo.src.full_height;
    pix->field = V4L2_FIELD_NONE;
    pix->pixelformat = layer->fmt->fourcc;
    pix->colorspace = layer->fmt->colorspace;
    mxr_mplane_fill(pix->plane_fmt, layer->fmt, pix->width, pix->height);

    return 0;
}

static int mxr_s_fmt(struct file *file, void *priv,
    struct v4l2_format *f)
{
    struct mxr_layer *layer = video_drvdata(file);
    const struct mxr_format *fmt;
    struct v4l2_pix_format_mplane *pix;
    struct mxr_device *mdev = layer->mdev;
    struct mxr_geometry *geo = &layer->geo;

    mxr_dbg(mdev, "%s:%d\n", __func__, __LINE__);

    pix = &f->fmt.pix_mp;
    fmt = find_format_by_fourcc(layer, pix->pixelformat);
    if (fmt == NULL) {
        mxr_warn(mdev, "not recognized fourcc: %08x\n",
            pix->pixelformat);
        return -EINVAL;
    }
    layer->fmt = fmt;
    /* set source size to highest accepted value */
    geo->src.full_width = max(geo->dst.full_width, pix->width);
    geo->src.full_height = max(geo->dst.full_height, pix->height);
    layer->ops.fix_geometry(layer, MXR_GEOMETRY_SOURCE, 0);
    mxr_geometry_dump(mdev, &layer->geo);
    /* set cropping to total visible screen */
    geo->src.width = pix->width;
    geo->src.height = pix->height;
    geo->src.x_offset = 0;
    geo->src.y_offset = 0;
    /* assure consistency of geometry */
    layer->ops.fix_geometry(layer, MXR_GEOMETRY_CROP, MXR_NO_OFFSET);
    mxr_geometry_dump(mdev, &layer->geo);
    /* set full size to lowest possible value */
    geo->src.full_width = 0;
    geo->src.full_height = 0;
    layer->ops.fix_geometry(layer, MXR_GEOMETRY_SOURCE, 0);
    mxr_geometry_dump(mdev, &layer->geo);

    /* returning results */
    mxr_g_fmt(file, priv, f);

    return 0;
}

static int mxr_g_selection(struct file *file, void *fh,
    struct v4l2_selection *s)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_geometry *geo = &layer->geo;

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);

    if (s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT &&
        s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
        return -EINVAL;

    switch (s->target) {
    case V4L2_SEL_TGT_CROP:
        s->r.left = geo->src.x_offset;
        s->r.top = geo->src.y_offset;
        s->r.width = geo->src.width;
        s->r.height = geo->src.height;
        break;
    case V4L2_SEL_TGT_CROP_DEFAULT:
    case V4L2_SEL_TGT_CROP_BOUNDS:
        s->r.left = 0;
        s->r.top = 0;
        s->r.width = geo->src.full_width;
        s->r.height = geo->src.full_height;
        break;
    case V4L2_SEL_TGT_COMPOSE:
    case V4L2_SEL_TGT_COMPOSE_PADDED:
        s->r.left = geo->dst.x_offset;
        s->r.top = geo->dst.y_offset;
        s->r.width = geo->dst.width;
        s->r.height = geo->dst.height;
        break;
    case V4L2_SEL_TGT_COMPOSE_DEFAULT:
    case V4L2_SEL_TGT_COMPOSE_BOUNDS:
        s->r.left = 0;
        s->r.top = 0;
        s->r.width = geo->dst.full_width;
        s->r.height = geo->dst.full_height;
        break;
    default:
        return -EINVAL;
    }

    return 0;
}

/* returns 1 if rectangle 'a' is inside 'b' */
static int mxr_is_rect_inside(struct v4l2_rect *a, struct v4l2_rect *b)
{
    if (a->left < b->left)
        return 0;
    if (a->top < b->top)
        return 0;
    if (a->left + a->width > b->left + b->width)
        return 0;
    if (a->top + a->height > b->top + b->height)
        return 0;
    return 1;
}

static int mxr_s_selection(struct file *file, void *fh,
    struct v4l2_selection *s)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_geometry *geo = &layer->geo;
    struct mxr_crop *target = NULL;
    enum mxr_geometry_stage stage;
    struct mxr_geometry tmp;
    struct v4l2_rect res;

    memset(&res, 0, sizeof res);

    mxr_dbg(layer->mdev, "%s: rect: %dx%d@%d,%d\n", __func__,
        s->r.width, s->r.height, s->r.left, s->r.top);

    if (s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT &&
        s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
        return -EINVAL;

    switch (s->target) {
    /* ignore read-only targets */
    case V4L2_SEL_TGT_CROP_DEFAULT:
    case V4L2_SEL_TGT_CROP_BOUNDS:
        res.width = geo->src.full_width;
        res.height = geo->src.full_height;
        break;

    /* ignore read-only targets */
    case V4L2_SEL_TGT_COMPOSE_DEFAULT:
    case V4L2_SEL_TGT_COMPOSE_BOUNDS:
        res.width = geo->dst.full_width;
        res.height = geo->dst.full_height;
        break;

    case V4L2_SEL_TGT_CROP:
        target = &geo->src;
        stage = MXR_GEOMETRY_CROP;
        break;
    case V4L2_SEL_TGT_COMPOSE:
    case V4L2_SEL_TGT_COMPOSE_PADDED:
        target = &geo->dst;
        stage = MXR_GEOMETRY_COMPOSE;
        break;
    default:
        return -EINVAL;
    }
    /* apply change and update geometry if needed */
    if (target) {
        /* backup current geometry if setup fails */
        memcpy(&tmp, geo, sizeof tmp);

        /* apply requested selection */
        target->x_offset = s->r.left;
        target->y_offset = s->r.top;
        target->width = s->r.width;
        target->height = s->r.height;

        layer->ops.fix_geometry(layer, stage, s->flags);

        /* retrieve update selection rectangle */
        res.left = target->x_offset;
        res.top = target->y_offset;
        res.width = target->width;
        res.height = target->height;

        mxr_geometry_dump(layer->mdev, &layer->geo);
    }

    /* checking if the rectangle satisfies constraints */
    if ((s->flags & V4L2_SEL_FLAG_LE) && !mxr_is_rect_inside(&res, &s->r))
        goto fail;
    if ((s->flags & V4L2_SEL_FLAG_GE) && !mxr_is_rect_inside(&s->r, &res))
        goto fail;

    /* return result rectangle */
    s->r = res;

    return 0;
fail:
    /* restore old geometry, which is not touched if target is NULL */
    if (target)
        memcpy(geo, &tmp, sizeof tmp);
    return -ERANGE;
}

static int mxr_enum_dv_presets(struct file *file, void *fh,
    struct v4l2_dv_enum_preset *preset)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret;

    /* lock protects from changing sd_out */
    mutex_lock(&mdev->mutex);
    ret = v4l2_subdev_call(to_outsd(mdev), video, enum_dv_presets, preset);
    mutex_unlock(&mdev->mutex);

    return ret ? -EINVAL : 0;
}

static int mxr_s_dv_preset(struct file *file, void *fh,
    struct v4l2_dv_preset *preset)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret;

    /* lock protects from changing sd_out */
    mutex_lock(&mdev->mutex);

    /* preset change cannot be done while there is an entity
     * dependant on output configuration
     */
    if (mdev->n_output > 0) {
        mutex_unlock(&mdev->mutex);
        return -EBUSY;
    }

    ret = v4l2_subdev_call(to_outsd(mdev), video, s_dv_preset, preset);

    mutex_unlock(&mdev->mutex);

    mxr_layer_update_output(layer);

    /* any failure should return EINVAL according to V4L2 doc */
    return ret ? -EINVAL : 0;
}

static int mxr_g_dv_preset(struct file *file, void *fh,
    struct v4l2_dv_preset *preset)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret;

    /* lock protects from changing sd_out */
    mutex_lock(&mdev->mutex);
    ret = v4l2_subdev_call(to_outsd(mdev), video, g_dv_preset, preset);
    mutex_unlock(&mdev->mutex);

    return ret ? -EINVAL : 0;
}

static int mxr_s_std(struct file *file, void *fh, v4l2_std_id *norm)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret;

    /* lock protects from changing sd_out */
    mutex_lock(&mdev->mutex);

    /* standard change cannot be done while there is an entity
     * dependant on output configuration
     */
    if (mdev->n_output > 0) {
        mutex_unlock(&mdev->mutex);
        return -EBUSY;
    }

    ret = v4l2_subdev_call(to_outsd(mdev), video, s_std_output, *norm);

    mutex_unlock(&mdev->mutex);

    mxr_layer_update_output(layer);

    return ret ? -EINVAL : 0;
}

static int mxr_g_std(struct file *file, void *fh, v4l2_std_id *norm)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret;

    /* lock protects from changing sd_out */
    mutex_lock(&mdev->mutex);
    ret = v4l2_subdev_call(to_outsd(mdev), video, g_std_output, norm);
    mutex_unlock(&mdev->mutex);

    return ret ? -EINVAL : 0;
}

static int mxr_enum_output(struct file *file, void *fh, struct v4l2_output *a)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    struct mxr_output *out;
    struct v4l2_subdev *sd;

    if (a->index >= mdev->output_cnt)
        return -EINVAL;
    out = mdev->output[a->index];
    BUG_ON(out == NULL);
    sd = out->sd;
    strlcpy(a->name, out->name, sizeof(a->name));

    /* try to obtain supported tv norms */
    v4l2_subdev_call(sd, video, g_tvnorms_output, &a->std);
    a->capabilities = 0;
    if (sd->ops->video && sd->ops->video->s_dv_preset)
        a->capabilities |= V4L2_OUT_CAP_PRESETS;
    if (sd->ops->video && sd->ops->video->s_std_output)
        a->capabilities |= V4L2_OUT_CAP_STD;
    a->type = V4L2_OUTPUT_TYPE_ANALOG;

    return 0;
}

static int mxr_s_output(struct file *file, void *fh, unsigned int i)
{
    struct video_device *vfd = video_devdata(file);
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;

    if (i >= mdev->output_cnt || mdev->output[i] == NULL)
        return -EINVAL;

    mutex_lock(&mdev->mutex);
    if (mdev->n_output > 0) {
        mutex_unlock(&mdev->mutex);
        return -EBUSY;
    }
    mdev->current_output = i;
    vfd->tvnorms = 0;
    v4l2_subdev_call(to_outsd(mdev), video, g_tvnorms_output,
        &vfd->tvnorms);
    mutex_unlock(&mdev->mutex);

    /* update layers geometry */
    mxr_layer_update_output(layer);

    mxr_dbg(mdev, "tvnorms = %08llx\n", vfd->tvnorms);

    return 0;
}

static int mxr_g_output(struct file *file, void *fh, unsigned int *p)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;

    mutex_lock(&mdev->mutex);
    *p = mdev->current_output;
    mutex_unlock(&mdev->mutex);

    return 0;
}

static int mxr_reqbufs(struct file *file, void *priv,
              struct v4l2_requestbuffers *p)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    return vb2_reqbufs(&layer->vb_queue, p);
}

static int mxr_querybuf(struct file *file, void *priv, struct v4l2_buffer *p)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    return vb2_querybuf(&layer->vb_queue, p);
}

static int mxr_qbuf(struct file *file, void *priv, struct v4l2_buffer *p)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d(%d)\n", __func__, __LINE__, p->index);
    return vb2_qbuf(&layer->vb_queue, p);
}

static int mxr_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    return vb2_dqbuf(&layer->vb_queue, p, file->f_flags & O_NONBLOCK);
}

static int mxr_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    return vb2_streamon(&layer->vb_queue, i);
}

static int mxr_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    return vb2_streamoff(&layer->vb_queue, i);
}

static const struct v4l2_ioctl_ops mxr_ioctl_ops = {
    .vidioc_querycap = mxr_querycap,
    /* format handling */
    .vidioc_enum_fmt_vid_out_mplane = mxr_enum_fmt,
    .vidioc_s_fmt_vid_out_mplane = mxr_s_fmt,
    .vidioc_g_fmt_vid_out_mplane = mxr_g_fmt,
    /* buffer control */
    .vidioc_reqbufs = mxr_reqbufs,
    .vidioc_querybuf = mxr_querybuf,
    .vidioc_qbuf = mxr_qbuf,
    .vidioc_dqbuf = mxr_dqbuf,
    /* Streaming control */
    .vidioc_streamon = mxr_streamon,
    .vidioc_streamoff = mxr_streamoff,
    /* Preset functions */
    .vidioc_enum_dv_presets = mxr_enum_dv_presets,
    .vidioc_s_dv_preset = mxr_s_dv_preset,
    .vidioc_g_dv_preset = mxr_g_dv_preset,
    /* analog TV standard functions */
    .vidioc_s_std = mxr_s_std,
    .vidioc_g_std = mxr_g_std,
    /* Output handling */
    .vidioc_enum_output = mxr_enum_output,
    .vidioc_s_output = mxr_s_output,
    .vidioc_g_output = mxr_g_output,
    /* selection ioctls */
    .vidioc_g_selection = mxr_g_selection,
    .vidioc_s_selection = mxr_s_selection,
};

static int mxr_video_open(struct file *file)
{
    struct mxr_layer *layer = video_drvdata(file);
    struct mxr_device *mdev = layer->mdev;
    int ret = 0;

    mxr_dbg(mdev, "%s:%d\n", __func__, __LINE__);
    if (mutex_lock_interruptible(&layer->mutex))
        return -ERESTARTSYS;
    /* assure device probe is finished */
    wait_for_device_probe();
    /* creating context for file descriptor */
    ret = v4l2_fh_open(file);
    if (ret) {
        mxr_err(mdev, "v4l2_fh_open failed\n");
        goto unlock;
    }

    /* leaving if layer is already initialized */
    if (!v4l2_fh_is_singular_file(file))
        goto unlock;

    /* FIXME: should power be enabled on open? */
    ret = mxr_power_get(mdev);
    if (ret) {
        mxr_err(mdev, "power on failed\n");
        goto fail_fh_open;
    }

    ret = vb2_queue_init(&layer->vb_queue);
    if (ret != 0) {
        mxr_err(mdev, "failed to initialize vb2 queue\n");
        goto fail_power;
    }
    /* set default format, first on the list */
    layer->fmt = layer->fmt_array[0];
    /* setup default geometry */
    mxr_layer_default_geo(layer);
    mutex_unlock(&layer->mutex);

    return 0;

fail_power:
    mxr_power_put(mdev);

fail_fh_open:
    v4l2_fh_release(file);

unlock:
    mutex_unlock(&layer->mutex);

    return ret;
}

static unsigned int
mxr_video_poll(struct file *file, struct poll_table_struct *wait)
{
    struct mxr_layer *layer = video_drvdata(file);
    unsigned int res;

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);

    mutex_lock(&layer->mutex);
    res = vb2_poll(&layer->vb_queue, file, wait);
    mutex_unlock(&layer->mutex);
    return res;
}

static int mxr_video_mmap(struct file *file, struct vm_area_struct *vma)
{
    struct mxr_layer *layer = video_drvdata(file);
    int ret;

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);

    if (mutex_lock_interruptible(&layer->mutex))
        return -ERESTARTSYS;
    ret = vb2_mmap(&layer->vb_queue, vma);
    mutex_unlock(&layer->mutex);
    return ret;
}

static int mxr_video_release(struct file *file)
{
    struct mxr_layer *layer = video_drvdata(file);

    mxr_dbg(layer->mdev, "%s:%d\n", __func__, __LINE__);
    mutex_lock(&layer->mutex);
    if (v4l2_fh_is_singular_file(file)) {
        vb2_queue_release(&layer->vb_queue);
        mxr_power_put(layer->mdev);
    }
    v4l2_fh_release(file);
    mutex_unlock(&layer->mutex);
    return 0;
}

static const struct v4l2_file_operations mxr_fops = {
    .owner = THIS_MODULE,
    .open = mxr_video_open,
    .poll = mxr_video_poll,
    .mmap = mxr_video_mmap,
    .release = mxr_video_release,
    .unlocked_ioctl = video_ioctl2,
};

static int queue_setup(struct vb2_queue *vq, const struct v4l2_format *pfmt,
    unsigned int *nbuffers, unsigned int *nplanes, unsigned int sizes[],
    void *alloc_ctxs[])
{
    struct mxr_layer *layer = vb2_get_drv_priv(vq);
    const struct mxr_format *fmt = layer->fmt;
    int i;
    struct mxr_device *mdev = layer->mdev;
    struct v4l2_plane_pix_format planes[3];

    mxr_dbg(mdev, "%s\n", __func__);
    /* checking if format was configured */
    if (fmt == NULL)
        return -EINVAL;
    mxr_dbg(mdev, "fmt = %s\n", fmt->name);
    mxr_mplane_fill(planes, fmt, layer->geo.src.full_width,
        layer->geo.src.full_height);

    *nplanes = fmt->num_subframes;
    for (i = 0; i < fmt->num_subframes; ++i) {
        alloc_ctxs[i] = layer->mdev->alloc_ctx;
        sizes[i] = planes[i].sizeimage;
        mxr_dbg(mdev, "size[%d] = %08x\n", i, sizes[i]);
    }

    if (*nbuffers == 0)
        *nbuffers = 1;

    return 0;
}

static void buf_queue(struct vb2_buffer *vb)
{
    struct mxr_buffer *buffer = container_of(vb, struct mxr_buffer, vb);
    struct mxr_layer *layer = vb2_get_drv_priv(vb->vb2_queue);
    struct mxr_device *mdev = layer->mdev;
    unsigned long flags;

    spin_lock_irqsave(&layer->enq_slock, flags);
    list_add_tail(&buffer->list, &layer->enq_list);
    spin_unlock_irqrestore(&layer->enq_slock, flags);

    mxr_dbg(mdev, "queuing buffer\n");
}

static void wait_lock(struct vb2_queue *vq)
{
    struct mxr_layer *layer = vb2_get_drv_priv(vq);

    mxr_dbg(layer->mdev, "%s\n", __func__);
    mutex_lock(&layer->mutex);
}

static void wait_unlock(struct vb2_queue *vq)
{
    struct mxr_layer *layer = vb2_get_drv_priv(vq);

    mxr_dbg(layer->mdev, "%s\n", __func__);
    mutex_unlock(&layer->mutex);
}

static int start_streaming(struct vb2_queue *vq, unsigned int count)
{
    struct mxr_layer *layer = vb2_get_drv_priv(vq);
    struct mxr_device *mdev = layer->mdev;
    unsigned long flags;

    mxr_dbg(mdev, "%s\n", __func__);

    if (count == 0) {
        mxr_dbg(mdev, "no output buffers queued\n");
        return -EINVAL;
    }

    /* block any changes in output configuration */
    mxr_output_get(mdev);

    mxr_layer_update_output(layer);
    layer->ops.format_set(layer);
    /* enabling layer in hardware */
    spin_lock_irqsave(&layer->enq_slock, flags);
    layer->state = MXR_LAYER_STREAMING;
    spin_unlock_irqrestore(&layer->enq_slock, flags);

    layer->ops.stream_set(layer, MXR_ENABLE);
    mxr_streamer_get(mdev);

    return 0;
}

static void mxr_watchdog(unsigned long arg)
{
    struct mxr_layer *layer = (struct mxr_layer *) arg;
    struct mxr_device *mdev = layer->mdev;
    unsigned long flags;

    mxr_err(mdev, "watchdog fired for layer %s\n", layer->vfd.name);

    spin_lock_irqsave(&layer->enq_slock, flags);

    if (layer->update_buf == layer->shadow_buf)
        layer->update_buf = NULL;
    if (layer->update_buf) {
        vb2_buffer_done(&layer->update_buf->vb, VB2_BUF_STATE_ERROR);
        layer->update_buf = NULL;
    }
    if (layer->shadow_buf) {
        vb2_buffer_done(&layer->shadow_buf->vb, VB2_BUF_STATE_ERROR);
        layer->shadow_buf = NULL;
    }
    spin_unlock_irqrestore(&layer->enq_slock, flags);
}

static int stop_streaming(struct vb2_queue *vq)
{
    struct mxr_layer *layer = vb2_get_drv_priv(vq);
    struct mxr_device *mdev = layer->mdev;
    unsigned long flags;
    struct timer_list watchdog;
    struct mxr_buffer *buf, *buf_tmp;

    mxr_dbg(mdev, "%s\n", __func__);

    spin_lock_irqsave(&layer->enq_slock, flags);

    /* reset list */
    layer->state = MXR_LAYER_STREAMING_FINISH;

    /* set all buffer to be done */
    list_for_each_entry_safe(buf, buf_tmp, &layer->enq_list, list) {
        list_del(&buf->list);
        vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
    }

    spin_unlock_irqrestore(&layer->enq_slock, flags);

    /* give 1 seconds to complete to complete last buffers */
    setup_timer_on_stack(&watchdog, mxr_watchdog,
        (unsigned long)layer);
    mod_timer(&watchdog, jiffies + msecs_to_jiffies(1000));

    /* wait until all buffers are goes to done state */
    vb2_wait_for_all_buffers(vq);

    /* stop timer if all synchronization is done */
    del_timer_sync(&watchdog);
    destroy_timer_on_stack(&watchdog);

    /* stopping hardware */
    spin_lock_irqsave(&layer->enq_slock, flags);
    layer->state = MXR_LAYER_IDLE;
    spin_unlock_irqrestore(&layer->enq_slock, flags);

    /* disabling layer in hardware */
    layer->ops.stream_set(layer, MXR_DISABLE);
    /* remove one streamer */
    mxr_streamer_put(mdev);
    /* allow changes in output configuration */
    mxr_output_put(mdev);
    return 0;
}

static struct vb2_ops mxr_video_qops = {
    .queue_setup = queue_setup,
    .buf_queue = buf_queue,
    .wait_prepare = wait_unlock,
    .wait_finish = wait_lock,
    .start_streaming = start_streaming,
    .stop_streaming = stop_streaming,
};

/* FIXME: try to put this functions to mxr_base_layer_create */
int mxr_base_layer_register(struct mxr_layer *layer)
{
    struct mxr_device *mdev = layer->mdev;
    int ret;

    ret = video_register_device(&layer->vfd, VFL_TYPE_GRABBER, -1);
    if (ret)
        mxr_err(mdev, "failed to register video device\n");
    else
        mxr_info(mdev, "registered layer %s as /dev/video%d\n",
            layer->vfd.name, layer->vfd.num);
    return ret;
}

void mxr_base_layer_unregister(struct mxr_layer *layer)
{
    video_unregister_device(&layer->vfd);
}

void mxr_layer_release(struct mxr_layer *layer)
{
    if (layer->ops.release)
        layer->ops.release(layer);
}

void mxr_base_layer_release(struct mxr_layer *layer)
{
    kfree(layer);
}

static void mxr_vfd_release(struct video_device *vdev)
{
    pr_info("video device release\n");
}

struct mxr_layer *mxr_base_layer_create(struct mxr_device *mdev,
    int idx, char *name, struct mxr_layer_ops *ops)
{
    struct mxr_layer *layer;

    layer = kzalloc(sizeof *layer, GFP_KERNEL);
    if (layer == NULL) {
        mxr_err(mdev, "not enough memory for layer.\n");
        goto fail;
    }

    layer->mdev = mdev;
    layer->idx = idx;
    layer->ops = *ops;

    spin_lock_init(&layer->enq_slock);
    INIT_LIST_HEAD(&layer->enq_list);
    mutex_init(&layer->mutex);

    layer->vfd = (struct video_device) {
        .minor = -1,
        .release = mxr_vfd_release,
        .fops = &mxr_fops,
        .vfl_dir = VFL_DIR_TX,
        .ioctl_ops = &mxr_ioctl_ops,
    };
    strlcpy(layer->vfd.name, name, sizeof(layer->vfd.name));
    /* let framework control PRIORITY */
    set_bit(V4L2_FL_USE_FH_PRIO, &layer->vfd.flags);

    video_set_drvdata(&layer->vfd, layer);
    layer->vfd.lock = &layer->mutex;
    layer->vfd.v4l2_dev = &mdev->v4l2_dev;

    layer->vb_queue = (struct vb2_queue) {
        .type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE,
        .io_modes = VB2_MMAP | VB2_USERPTR,
        .drv_priv = layer,
        .buf_struct_size = sizeof(struct mxr_buffer),
        .ops = &mxr_video_qops,
        .mem_ops = &vb2_dma_contig_memops,
    };

    return layer;

fail:
    return NULL;
}

static const struct mxr_format *find_format_by_fourcc(
    struct mxr_layer *layer, unsigned long fourcc)
{
    int i;

    for (i = 0; i < layer->fmt_array_size; ++i)
        if (layer->fmt_array[i]->fourcc == fourcc)
            return layer->fmt_array[i];
    return NULL;
}

static const struct mxr_format *find_format_by_index(
    struct mxr_layer *layer, unsigned long index)
{
    if (index >= layer->fmt_array_size)
        return NULL;
    return layer->fmt_array[index];
}