diff options
Diffstat (limited to 'drivers/media/usb/uvc/uvc_metadata.c')
| -rw-r--r-- | drivers/media/usb/uvc/uvc_metadata.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/media/usb/uvc/uvc_metadata.c b/drivers/media/usb/uvc/uvc_metadata.c new file mode 100644 index 000000000..82de7781f --- /dev/null +++ b/drivers/media/usb/uvc/uvc_metadata.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * uvc_metadata.c -- USB Video Class driver - Metadata handling + * + * Copyright (C) 2016 + * Guennadi Liakhovetski (guennadi.liakhovetski@intel.com) + */ + +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/videodev2.h> + +#include <media/v4l2-ioctl.h> +#include <media/videobuf2-v4l2.h> +#include <media/videobuf2-vmalloc.h> + +#include "uvcvideo.h" + +/* ----------------------------------------------------------------------------- + * V4L2 ioctls + */ + +static int uvc_meta_v4l2_querycap(struct file *file, void *fh, + struct v4l2_capability *cap) +{ + struct v4l2_fh *vfh = file->private_data; + struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); + struct uvc_video_chain *chain = stream->chain; + + strscpy(cap->driver, "uvcvideo", sizeof(cap->driver)); + strscpy(cap->card, stream->dev->name, sizeof(cap->card)); + usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info)); + cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING + | chain->caps; + + return 0; +} + +static int uvc_meta_v4l2_get_format(struct file *file, void *fh, + struct v4l2_format *format) +{ + struct v4l2_fh *vfh = file->private_data; + struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); + struct v4l2_meta_format *fmt = &format->fmt.meta; + + if (format->type != vfh->vdev->queue->type) + return -EINVAL; + + memset(fmt, 0, sizeof(*fmt)); + + fmt->dataformat = stream->meta.format; + fmt->buffersize = UVC_METADATA_BUF_SIZE; + + return 0; +} + +static int uvc_meta_v4l2_try_format(struct file *file, void *fh, + struct v4l2_format *format) +{ + struct v4l2_fh *vfh = file->private_data; + struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); + struct uvc_device *dev = stream->dev; + struct v4l2_meta_format *fmt = &format->fmt.meta; + u32 fmeta = fmt->dataformat; + + if (format->type != vfh->vdev->queue->type) + return -EINVAL; + + memset(fmt, 0, sizeof(*fmt)); + + fmt->dataformat = fmeta == dev->info->meta_format + ? fmeta : V4L2_META_FMT_UVC; + fmt->buffersize = UVC_METADATA_BUF_SIZE; + + return 0; +} + +static int uvc_meta_v4l2_set_format(struct file *file, void *fh, + struct v4l2_format *format) +{ + struct v4l2_fh *vfh = file->private_data; + struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); + struct v4l2_meta_format *fmt = &format->fmt.meta; + int ret; + + ret = uvc_meta_v4l2_try_format(file, fh, format); + if (ret < 0) + return ret; + + /* + * We could in principle switch at any time, also during streaming. + * Metadata buffers would still be perfectly parseable, but it's more + * consistent and cleaner to disallow that. + */ + mutex_lock(&stream->mutex); + + if (uvc_queue_allocated(&stream->queue)) + ret = -EBUSY; + else + stream->meta.format = fmt->dataformat; + + mutex_unlock(&stream->mutex); + + return ret; +} + +static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh, + struct v4l2_fmtdesc *fdesc) +{ + struct v4l2_fh *vfh = file->private_data; + struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); + struct uvc_device *dev = stream->dev; + u32 index = fdesc->index; + + if (fdesc->type != vfh->vdev->queue->type || + index > 1U || (index && !dev->info->meta_format)) + return -EINVAL; + + memset(fdesc, 0, sizeof(*fdesc)); + + fdesc->type = vfh->vdev->queue->type; + fdesc->index = index; + fdesc->pixelformat = index ? dev->info->meta_format : V4L2_META_FMT_UVC; + + return 0; +} + +static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = { + .vidioc_querycap = uvc_meta_v4l2_querycap, + .vidioc_g_fmt_meta_cap = uvc_meta_v4l2_get_format, + .vidioc_s_fmt_meta_cap = uvc_meta_v4l2_set_format, + .vidioc_try_fmt_meta_cap = uvc_meta_v4l2_try_format, + .vidioc_enum_fmt_meta_cap = uvc_meta_v4l2_enum_formats, + .vidioc_reqbufs = vb2_ioctl_reqbufs, + .vidioc_querybuf = vb2_ioctl_querybuf, + .vidioc_qbuf = vb2_ioctl_qbuf, + .vidioc_dqbuf = vb2_ioctl_dqbuf, + .vidioc_create_bufs = vb2_ioctl_create_bufs, + .vidioc_prepare_buf = vb2_ioctl_prepare_buf, + .vidioc_streamon = vb2_ioctl_streamon, + .vidioc_streamoff = vb2_ioctl_streamoff, +}; + +/* ----------------------------------------------------------------------------- + * V4L2 File Operations + */ + +static const struct v4l2_file_operations uvc_meta_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = video_ioctl2, + .open = v4l2_fh_open, + .release = vb2_fop_release, + .poll = vb2_fop_poll, + .mmap = vb2_fop_mmap, +}; + +int uvc_meta_register(struct uvc_streaming *stream) +{ + struct uvc_device *dev = stream->dev; + struct video_device *vdev = &stream->meta.vdev; + struct uvc_video_queue *queue = &stream->meta.queue; + + stream->meta.format = V4L2_META_FMT_UVC; + + /* + * The video interface queue uses manual locking and thus does not set + * the queue pointer. Set it manually here. + */ + vdev->queue = &queue->queue; + + return uvc_register_video_device(dev, stream, vdev, queue, + V4L2_BUF_TYPE_META_CAPTURE, + &uvc_meta_fops, &uvc_meta_ioctl_ops); +} |