v4l2-subdev.c

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/*
 * V4L2 sub-device
 *
 * Copyright (C) 2010 Nokia Corporation
 *
 * Contact: Laurent Pinchart <[email protected]>
 *      Sakari Ailus <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/ioctl.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/videodev2.h>
#include <linux/export.h>

#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-event.h>

static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
{
#if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
    fh->pad = kzalloc(sizeof(*fh->pad) * sd->entity.num_pads, GFP_KERNEL);
    if (fh->pad == NULL)
        return -ENOMEM;
#endif
    return 0;
}

static void subdev_fh_free(struct v4l2_subdev_fh *fh)
{
#if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
    kfree(fh->pad);
    fh->pad = NULL;
#endif
}

static int subdev_open(struct file *file)
{
    struct video_device *vdev = video_devdata(file);
    struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
    struct v4l2_subdev_fh *subdev_fh;
#if defined(CONFIG_MEDIA_CONTROLLER)
    struct media_entity *entity = NULL;
#endif
    int ret;

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

    ret = subdev_fh_init(subdev_fh, sd);
    if (ret) {
        kfree(subdev_fh);
        return ret;
    }

    v4l2_fh_init(&subdev_fh->vfh, vdev);
    v4l2_fh_add(&subdev_fh->vfh);
    file->private_data = &subdev_fh->vfh;
#if defined(CONFIG_MEDIA_CONTROLLER)
    if (sd->v4l2_dev->mdev) {
        entity = media_entity_get(&sd->entity);
        if (!entity) {
            ret = -EBUSY;
            goto err;
        }
    }
#endif

    if (sd->internal_ops && sd->internal_ops->open) {
        ret = sd->internal_ops->open(sd, subdev_fh);
        if (ret < 0)
            goto err;
    }

    return 0;

err:
#if defined(CONFIG_MEDIA_CONTROLLER)
    if (entity)
        media_entity_put(entity);
#endif
    v4l2_fh_del(&subdev_fh->vfh);
    v4l2_fh_exit(&subdev_fh->vfh);
    subdev_fh_free(subdev_fh);
    kfree(subdev_fh);

    return ret;
}

static int subdev_close(struct file *file)
{
    struct video_device *vdev = video_devdata(file);
    struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
    struct v4l2_fh *vfh = file->private_data;
    struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);

    if (sd->internal_ops && sd->internal_ops->close)
        sd->internal_ops->close(sd, subdev_fh);
#if defined(CONFIG_MEDIA_CONTROLLER)
    if (sd->v4l2_dev->mdev)
        media_entity_put(&sd->entity);
#endif
    v4l2_fh_del(vfh);
    v4l2_fh_exit(vfh);
    subdev_fh_free(subdev_fh);
    kfree(subdev_fh);
    file->private_data = NULL;

    return 0;
}

static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
{
    struct video_device *vdev = video_devdata(file);
    struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
    struct v4l2_fh *vfh = file->private_data;
#if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
    struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);
#endif

    switch (cmd) {
    case VIDIOC_QUERYCTRL:
        return v4l2_queryctrl(vfh->ctrl_handler, arg);

    case VIDIOC_QUERYMENU:
        return v4l2_querymenu(vfh->ctrl_handler, arg);

    case VIDIOC_G_CTRL:
        return v4l2_g_ctrl(vfh->ctrl_handler, arg);

    case VIDIOC_S_CTRL:
        return v4l2_s_ctrl(vfh, vfh->ctrl_handler, arg);

    case VIDIOC_G_EXT_CTRLS:
        return v4l2_g_ext_ctrls(vfh->ctrl_handler, arg);

    case VIDIOC_S_EXT_CTRLS:
        return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler, arg);

    case VIDIOC_TRY_EXT_CTRLS:
        return v4l2_try_ext_ctrls(vfh->ctrl_handler, arg);

    case VIDIOC_DQEVENT:
        if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))
            return -ENOIOCTLCMD;

        return v4l2_event_dequeue(vfh, arg, file->f_flags & O_NONBLOCK);

    case VIDIOC_SUBSCRIBE_EVENT:
        return v4l2_subdev_call(sd, core, subscribe_event, vfh, arg);

    case VIDIOC_UNSUBSCRIBE_EVENT:
        return v4l2_subdev_call(sd, core, unsubscribe_event, vfh, arg);

#ifdef CONFIG_VIDEO_ADV_DEBUG
    case VIDIOC_DBG_G_REGISTER:
    {
        struct v4l2_dbg_register *p = arg;

        if (!capable(CAP_SYS_ADMIN))
            return -EPERM;
        return v4l2_subdev_call(sd, core, g_register, p);
    }
    case VIDIOC_DBG_S_REGISTER:
    {
        struct v4l2_dbg_register *p = arg;

        if (!capable(CAP_SYS_ADMIN))
            return -EPERM;
        return v4l2_subdev_call(sd, core, s_register, p);
    }
#endif

    case VIDIOC_LOG_STATUS: {
        int ret;

        pr_info("%s: =================  START STATUS  =================\n",
            sd->name);
        ret = v4l2_subdev_call(sd, core, log_status);
        pr_info("%s: ==================  END STATUS  ==================\n",
            sd->name);
        return ret;
    }

#if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
    case VIDIOC_SUBDEV_G_FMT: {
        struct v4l2_subdev_format *format = arg;

        if (format->which != V4L2_SUBDEV_FORMAT_TRY &&
            format->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (format->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(sd, pad, get_fmt, subdev_fh, format);
    }

    case VIDIOC_SUBDEV_S_FMT: {
        struct v4l2_subdev_format *format = arg;

        if (format->which != V4L2_SUBDEV_FORMAT_TRY &&
            format->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (format->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(sd, pad, set_fmt, subdev_fh, format);
    }

    case VIDIOC_SUBDEV_G_CROP: {
        struct v4l2_subdev_crop *crop = arg;
        struct v4l2_subdev_selection sel;
        int rval;

        if (crop->which != V4L2_SUBDEV_FORMAT_TRY &&
            crop->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (crop->pad >= sd->entity.num_pads)
            return -EINVAL;

        rval = v4l2_subdev_call(sd, pad, get_crop, subdev_fh, crop);
        if (rval != -ENOIOCTLCMD)
            return rval;

        memset(&sel, 0, sizeof(sel));
        sel.which = crop->which;
        sel.pad = crop->pad;
        sel.target = V4L2_SEL_TGT_CROP;

        rval = v4l2_subdev_call(
            sd, pad, get_selection, subdev_fh, &sel);

        crop->rect = sel.r;

        return rval;
    }

    case VIDIOC_SUBDEV_S_CROP: {
        struct v4l2_subdev_crop *crop = arg;
        struct v4l2_subdev_selection sel;
        int rval;

        if (crop->which != V4L2_SUBDEV_FORMAT_TRY &&
            crop->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (crop->pad >= sd->entity.num_pads)
            return -EINVAL;

        rval = v4l2_subdev_call(sd, pad, set_crop, subdev_fh, crop);
        if (rval != -ENOIOCTLCMD)
            return rval;

        memset(&sel, 0, sizeof(sel));
        sel.which = crop->which;
        sel.pad = crop->pad;
        sel.target = V4L2_SEL_TGT_CROP;
        sel.r = crop->rect;

        rval = v4l2_subdev_call(
            sd, pad, set_selection, subdev_fh, &sel);

        crop->rect = sel.r;

        return rval;
    }

    case VIDIOC_SUBDEV_ENUM_MBUS_CODE: {
        struct v4l2_subdev_mbus_code_enum *code = arg;

        if (code->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(sd, pad, enum_mbus_code, subdev_fh,
                    code);
    }

    case VIDIOC_SUBDEV_ENUM_FRAME_SIZE: {
        struct v4l2_subdev_frame_size_enum *fse = arg;

        if (fse->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(sd, pad, enum_frame_size, subdev_fh,
                    fse);
    }

    case VIDIOC_SUBDEV_G_FRAME_INTERVAL:
        return v4l2_subdev_call(sd, video, g_frame_interval, arg);

    case VIDIOC_SUBDEV_S_FRAME_INTERVAL:
        return v4l2_subdev_call(sd, video, s_frame_interval, arg);

    case VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL: {
        struct v4l2_subdev_frame_interval_enum *fie = arg;

        if (fie->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(sd, pad, enum_frame_interval, subdev_fh,
                    fie);
    }

    case VIDIOC_SUBDEV_G_SELECTION: {
        struct v4l2_subdev_selection *sel = arg;

        if (sel->which != V4L2_SUBDEV_FORMAT_TRY &&
            sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (sel->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(
            sd, pad, get_selection, subdev_fh, sel);
    }

    case VIDIOC_SUBDEV_S_SELECTION: {
        struct v4l2_subdev_selection *sel = arg;

        if (sel->which != V4L2_SUBDEV_FORMAT_TRY &&
            sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
            return -EINVAL;

        if (sel->pad >= sd->entity.num_pads)
            return -EINVAL;

        return v4l2_subdev_call(
            sd, pad, set_selection, subdev_fh, sel);
    }

    case VIDIOC_SUBDEV_G_EDID:
        return v4l2_subdev_call(sd, pad, get_edid, arg);

    case VIDIOC_SUBDEV_S_EDID:
        return v4l2_subdev_call(sd, pad, set_edid, arg);
#endif
    default:
        return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
    }

    return 0;
}

static long subdev_ioctl(struct file *file, unsigned int cmd,
    unsigned long arg)
{
    return video_usercopy(file, cmd, arg, subdev_do_ioctl);
}

static unsigned int subdev_poll(struct file *file, poll_table *wait)
{
    struct video_device *vdev = video_devdata(file);
    struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
    struct v4l2_fh *fh = file->private_data;

    if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))
        return POLLERR;

    poll_wait(file, &fh->wait, wait);

    if (v4l2_event_pending(fh))
        return POLLPRI;

    return 0;
}

const struct v4l2_file_operations v4l2_subdev_fops = {
    .owner = THIS_MODULE,
    .open = subdev_open,
    .unlocked_ioctl = subdev_ioctl,
    .release = subdev_close,
    .poll = subdev_poll,
};

#ifdef CONFIG_MEDIA_CONTROLLER
int v4l2_subdev_link_validate_default(struct v4l2_subdev *sd,
                      struct media_link *link,
                      struct v4l2_subdev_format *source_fmt,
                      struct v4l2_subdev_format *sink_fmt)
{
    if (source_fmt->format.width != sink_fmt->format.width
        || source_fmt->format.height != sink_fmt->format.height
        || source_fmt->format.code != sink_fmt->format.code)
        return -EINVAL;

    return 0;
}
EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate_default);

static int
v4l2_subdev_link_validate_get_format(struct media_pad *pad,
                     struct v4l2_subdev_format *fmt)
{
    switch (media_entity_type(pad->entity)) {
    case MEDIA_ENT_T_V4L2_SUBDEV:
        fmt->which = V4L2_SUBDEV_FORMAT_ACTIVE;
        fmt->pad = pad->index;
        return v4l2_subdev_call(media_entity_to_v4l2_subdev(
                        pad->entity),
                    pad, get_fmt, NULL, fmt);
    default:
        WARN(1, "Driver bug! Wrong media entity type %d, entity %s\n",
             media_entity_type(pad->entity), pad->entity->name);
        /* Fall through */
    case MEDIA_ENT_T_DEVNODE_V4L:
        return -EINVAL;
    }
}

int v4l2_subdev_link_validate(struct media_link *link)
{
    struct v4l2_subdev *sink;
    struct v4l2_subdev_format sink_fmt, source_fmt;
    int rval;

    rval = v4l2_subdev_link_validate_get_format(
        link->source, &source_fmt);
    if (rval < 0)
        return 0;

    rval = v4l2_subdev_link_validate_get_format(
        link->sink, &sink_fmt);
    if (rval < 0)
        return 0;

    sink = media_entity_to_v4l2_subdev(link->sink->entity);

    rval = v4l2_subdev_call(sink, pad, link_validate, link,
                &source_fmt, &sink_fmt);
    if (rval != -ENOIOCTLCMD)
        return rval;

    return v4l2_subdev_link_validate_default(
        sink, link, &source_fmt, &sink_fmt);
}
EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
#endif /* CONFIG_MEDIA_CONTROLLER */

void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
{
    INIT_LIST_HEAD(&sd->list);
    BUG_ON(!ops);
    sd->ops = ops;
    sd->v4l2_dev = NULL;
    sd->flags = 0;
    sd->name[0] = '\0';
    sd->grp_id = 0;
    sd->dev_priv = NULL;
    sd->host_priv = NULL;
#if defined(CONFIG_MEDIA_CONTROLLER)
    sd->entity.name = sd->name;
    sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV;
#endif
}
EXPORT_SYMBOL(v4l2_subdev_init);