* [RFC PATCHv2] uvc: use vb2 ioctl and fop helpers
@ 2021-03-12 10:33 Hans Verkuil
2021-03-12 22:13 ` Laurent Pinchart
0 siblings, 1 reply; 2+ messages in thread
From: Hans Verkuil @ 2021-03-12 10:33 UTC (permalink / raw)
To: Linux Media Mailing List; +Cc: Ricardo Ribalda Delgado, Laurent Pinchart
When uvc was written the vb2 ioctl and file operation helpers didn't exist.
This patch switches uvc over to those helpers, which removes a lot of boilerplate
code and simplifies VIDIOC_G/S_PRIORITY handling and allows us to drop the
'privileges' scheme, since that's now handled inside the vb2 helpers.
This makes it possible for uvc to pass the v4l2-compliance streaming tests.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
Changes since v1:
- use correct queue for metadata
TODO:
- vb2_fop_get_unmapped_area() should probably be used as well
- verify suspend/resume
- for extra bonus points: test if unbind of the driver works while streaming
---
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 30ef2a3110f7..dfaadb5c1bae 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -1911,7 +1911,6 @@ static struct uvc_video_chain *uvc_alloc_chain(struct uvc_device *dev)
INIT_LIST_HEAD(&chain->entities);
mutex_init(&chain->ctrl_mutex);
chain->dev = dev;
- v4l2_prio_init(&chain->prio);
return chain;
}
@@ -2180,7 +2179,7 @@ int uvc_register_video_device(struct uvc_device *dev,
vdev->fops = fops;
vdev->ioctl_ops = ioctl_ops;
vdev->release = uvc_release;
- vdev->prio = &stream->chain->prio;
+ vdev->queue = &queue->queue;
if (type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
vdev->vfl_dir = VFL_DIR_TX;
else
@@ -2541,8 +2540,8 @@ static int __uvc_resume(struct usb_interface *intf, int reset)
if (stream->intf == intf) {
ret = uvc_video_resume(stream, reset);
if (ret < 0)
- uvc_queue_streamoff(&stream->queue,
- stream->queue.queue.type);
+ vb2_streamoff(&stream->queue.queue,
+ stream->queue.queue.type);
return ret;
}
}
diff --git a/drivers/media/usb/uvc/uvc_metadata.c b/drivers/media/usb/uvc/uvc_metadata.c
index b6279ad7ac84..2f52cdc62929 100644
--- a/drivers/media/usb/uvc/uvc_metadata.c
+++ b/drivers/media/usb/uvc/uvc_metadata.c
@@ -96,7 +96,7 @@ static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
*/
mutex_lock(&stream->mutex);
- if (uvc_queue_allocated(&stream->queue))
+ if (vb2_is_busy(&stream->queue.queue))
ret = -EBUSY;
else
stream->meta.format = fmt->dataformat;
@@ -164,12 +164,6 @@ int uvc_meta_register(struct uvc_streaming *stream)
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);
diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
index 21a907d32bb7..fba9646c8ba5 100644
--- a/drivers/media/usb/uvc/uvc_queue.c
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -247,115 +247,10 @@ int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
return 0;
}
-void uvc_queue_release(struct uvc_video_queue *queue)
-{
- mutex_lock(&queue->mutex);
- vb2_queue_release(&queue->queue);
- mutex_unlock(&queue->mutex);
-}
-
/* -----------------------------------------------------------------------------
* V4L2 queue operations
*/
-int uvc_request_buffers(struct uvc_video_queue *queue,
- struct v4l2_requestbuffers *rb)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_reqbufs(&queue->queue, rb);
- mutex_unlock(&queue->mutex);
-
- return ret ? ret : rb->count;
-}
-
-int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_querybuf(&queue->queue, buf);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_create_buffers(struct uvc_video_queue *queue,
- struct v4l2_create_buffers *cb)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_create_bufs(&queue->queue, cb);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_queue_buffer(struct uvc_video_queue *queue,
- struct media_device *mdev, struct v4l2_buffer *buf)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_qbuf(&queue->queue, mdev, buf);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_export_buffer(struct uvc_video_queue *queue,
- struct v4l2_exportbuffer *exp)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_expbuf(&queue->queue, exp);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
- int nonblocking)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_dqbuf(&queue->queue, buf, nonblocking);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_streamon(&queue->queue, type);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type)
-{
- int ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_streamoff(&queue->queue, type);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
-int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
-{
- return vb2_mmap(&queue->queue, vma);
-}
-
#ifndef CONFIG_MMU
unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
unsigned long pgoff)
@@ -364,36 +259,10 @@ unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
}
#endif
-__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
- poll_table *wait)
-{
- __poll_t ret;
-
- mutex_lock(&queue->mutex);
- ret = vb2_poll(&queue->queue, file, wait);
- mutex_unlock(&queue->mutex);
-
- return ret;
-}
-
/* -----------------------------------------------------------------------------
*
*/
-/*
- * Check if buffers have been allocated.
- */
-int uvc_queue_allocated(struct uvc_video_queue *queue)
-{
- int allocated;
-
- mutex_lock(&queue->mutex);
- allocated = vb2_is_busy(&queue->queue);
- mutex_unlock(&queue->mutex);
-
- return allocated;
-}
-
/*
* Cancel the video buffers queue.
*
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 252136cc885c..13ff1c9590c2 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -346,17 +346,13 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream,
return ret;
mutex_lock(&stream->mutex);
-
- if (uvc_queue_allocated(&stream->queue)) {
+ if (vb2_is_busy(&stream->queue.queue)) {
ret = -EBUSY;
- goto done;
+ } else {
+ stream->ctrl = probe;
+ stream->cur_format = format;
+ stream->cur_frame = frame;
}
-
- stream->ctrl = probe;
- stream->cur_format = format;
- stream->cur_frame = frame;
-
-done:
mutex_unlock(&stream->mutex);
return ret;
}
@@ -480,62 +476,6 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
return 0;
}
-/* ------------------------------------------------------------------------
- * Privilege management
- */
-
-/*
- * Privilege management is the multiple-open implementation basis. The current
- * implementation is completely transparent for the end-user and doesn't
- * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
- * Those ioctls enable finer control on the device (by making possible for a
- * user to request exclusive access to a device), but are not mature yet.
- * Switching to the V4L2 priority mechanism might be considered in the future
- * if this situation changes.
- *
- * Each open instance of a UVC device can either be in a privileged or
- * unprivileged state. Only a single instance can be in a privileged state at
- * a given time. Trying to perform an operation that requires privileges will
- * automatically acquire the required privileges if possible, or return -EBUSY
- * otherwise. Privileges are dismissed when closing the instance or when
- * freeing the video buffers using VIDIOC_REQBUFS.
- *
- * Operations that require privileges are:
- *
- * - VIDIOC_S_INPUT
- * - VIDIOC_S_PARM
- * - VIDIOC_S_FMT
- * - VIDIOC_REQBUFS
- */
-static int uvc_acquire_privileges(struct uvc_fh *handle)
-{
- /* Always succeed if the handle is already privileged. */
- if (handle->state == UVC_HANDLE_ACTIVE)
- return 0;
-
- /* Check if the device already has a privileged handle. */
- if (atomic_inc_return(&handle->stream->active) != 1) {
- atomic_dec(&handle->stream->active);
- return -EBUSY;
- }
-
- handle->state = UVC_HANDLE_ACTIVE;
- return 0;
-}
-
-static void uvc_dismiss_privileges(struct uvc_fh *handle)
-{
- if (handle->state == UVC_HANDLE_ACTIVE)
- atomic_dec(&handle->stream->active);
-
- handle->state = UVC_HANDLE_PASSIVE;
-}
-
-static int uvc_has_privileges(struct uvc_fh *handle)
-{
- return handle->state == UVC_HANDLE_ACTIVE;
-}
-
/* ------------------------------------------------------------------------
* V4L2 file operations
*/
@@ -578,7 +518,6 @@ static int uvc_v4l2_open(struct file *file)
v4l2_fh_add(&handle->vfh);
handle->chain = stream->chain;
handle->stream = stream;
- handle->state = UVC_HANDLE_PASSIVE;
file->private_data = handle;
return 0;
@@ -591,15 +530,8 @@ static int uvc_v4l2_release(struct file *file)
uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
- /* Only free resources if this is a privileged handle. */
- if (uvc_has_privileges(handle))
- uvc_queue_release(&stream->queue);
-
/* Release the file handle. */
- uvc_dismiss_privileges(handle);
- v4l2_fh_del(&handle->vfh);
- v4l2_fh_exit(&handle->vfh);
- kfree(handle);
+ vb2_fop_release(file);
file->private_data = NULL;
mutex_lock(&stream->dev->lock);
@@ -693,11 +625,6 @@ static int uvc_ioctl_s_fmt_vid_cap(struct file *file, void *fh,
{
struct uvc_fh *handle = fh;
struct uvc_streaming *stream = handle->stream;
- int ret;
-
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
return uvc_v4l2_set_format(stream, fmt);
}
@@ -707,11 +634,6 @@ static int uvc_ioctl_s_fmt_vid_out(struct file *file, void *fh,
{
struct uvc_fh *handle = fh;
struct uvc_streaming *stream = handle->stream;
- int ret;
-
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
return uvc_v4l2_set_format(stream, fmt);
}
@@ -736,124 +658,6 @@ static int uvc_ioctl_try_fmt_vid_out(struct file *file, void *fh,
return uvc_v4l2_try_format(stream, fmt, &probe, NULL, NULL);
}
-static int uvc_ioctl_reqbufs(struct file *file, void *fh,
- struct v4l2_requestbuffers *rb)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
- int ret;
-
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
-
- mutex_lock(&stream->mutex);
- ret = uvc_request_buffers(&stream->queue, rb);
- mutex_unlock(&stream->mutex);
- if (ret < 0)
- return ret;
-
- if (ret == 0)
- uvc_dismiss_privileges(handle);
-
- return 0;
-}
-
-static int uvc_ioctl_querybuf(struct file *file, void *fh,
- struct v4l2_buffer *buf)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- return uvc_query_buffer(&stream->queue, buf);
-}
-
-static int uvc_ioctl_qbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- return uvc_queue_buffer(&stream->queue,
- stream->vdev.v4l2_dev->mdev, buf);
-}
-
-static int uvc_ioctl_expbuf(struct file *file, void *fh,
- struct v4l2_exportbuffer *exp)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- return uvc_export_buffer(&stream->queue, exp);
-}
-
-static int uvc_ioctl_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- return uvc_dequeue_buffer(&stream->queue, buf,
- file->f_flags & O_NONBLOCK);
-}
-
-static int uvc_ioctl_create_bufs(struct file *file, void *fh,
- struct v4l2_create_buffers *cb)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
- int ret;
-
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
-
- return uvc_create_buffers(&stream->queue, cb);
-}
-
-static int uvc_ioctl_streamon(struct file *file, void *fh,
- enum v4l2_buf_type type)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
- int ret;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- mutex_lock(&stream->mutex);
- ret = uvc_queue_streamon(&stream->queue, type);
- mutex_unlock(&stream->mutex);
-
- return ret;
-}
-
-static int uvc_ioctl_streamoff(struct file *file, void *fh,
- enum v4l2_buf_type type)
-{
- struct uvc_fh *handle = fh;
- struct uvc_streaming *stream = handle->stream;
-
- if (!uvc_has_privileges(handle))
- return -EBUSY;
-
- mutex_lock(&stream->mutex);
- uvc_queue_streamoff(&stream->queue, type);
- mutex_unlock(&stream->mutex);
-
- return 0;
-}
-
static int uvc_ioctl_enum_input(struct file *file, void *fh,
struct v4l2_input *input)
{
@@ -921,13 +725,12 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input)
static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input)
{
struct uvc_fh *handle = fh;
+ struct uvc_streaming *stream = handle->stream;
struct uvc_video_chain *chain = handle->chain;
- int ret;
u32 i;
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
+ if (vb2_is_busy(&stream->queue.queue))
+ return -EBUSY;
if (chain->selector == NULL ||
(chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
@@ -1187,11 +990,6 @@ static int uvc_ioctl_s_parm(struct file *file, void *fh,
{
struct uvc_fh *handle = fh;
struct uvc_streaming *stream = handle->stream;
- int ret;
-
- ret = uvc_acquire_privileges(handle);
- if (ret < 0)
- return ret;
return uvc_v4l2_set_streamparm(stream, parm);
}
@@ -1459,36 +1257,6 @@ static long uvc_v4l2_compat_ioctl32(struct file *file,
}
#endif
-static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
- size_t count, loff_t *ppos)
-{
- struct uvc_fh *handle = file->private_data;
- struct uvc_streaming *stream = handle->stream;
-
- uvc_dbg(stream->dev, CALLS, "%s: not implemented\n", __func__);
- return -EINVAL;
-}
-
-static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
-{
- struct uvc_fh *handle = file->private_data;
- struct uvc_streaming *stream = handle->stream;
-
- uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
-
- return uvc_queue_mmap(&stream->queue, vma);
-}
-
-static __poll_t uvc_v4l2_poll(struct file *file, poll_table *wait)
-{
- struct uvc_fh *handle = file->private_data;
- struct uvc_streaming *stream = handle->stream;
-
- uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
-
- return uvc_queue_poll(&stream->queue, file, wait);
-}
-
#ifndef CONFIG_MMU
static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
unsigned long addr, unsigned long len, unsigned long pgoff,
@@ -1513,14 +1281,15 @@ const struct v4l2_ioctl_ops uvc_ioctl_ops = {
.vidioc_s_fmt_vid_out = uvc_ioctl_s_fmt_vid_out,
.vidioc_try_fmt_vid_cap = uvc_ioctl_try_fmt_vid_cap,
.vidioc_try_fmt_vid_out = uvc_ioctl_try_fmt_vid_out,
- .vidioc_reqbufs = uvc_ioctl_reqbufs,
- .vidioc_querybuf = uvc_ioctl_querybuf,
- .vidioc_qbuf = uvc_ioctl_qbuf,
- .vidioc_expbuf = uvc_ioctl_expbuf,
- .vidioc_dqbuf = uvc_ioctl_dqbuf,
- .vidioc_create_bufs = uvc_ioctl_create_bufs,
- .vidioc_streamon = uvc_ioctl_streamon,
- .vidioc_streamoff = uvc_ioctl_streamoff,
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_expbuf = vb2_ioctl_expbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
.vidioc_enum_input = uvc_ioctl_enum_input,
.vidioc_g_input = uvc_ioctl_g_input,
.vidioc_s_input = uvc_ioctl_s_input,
@@ -1550,9 +1319,8 @@ const struct v4l2_file_operations uvc_fops = {
#ifdef CONFIG_COMPAT
.compat_ioctl32 = uvc_v4l2_compat_ioctl32,
#endif
- .read = uvc_v4l2_read,
- .mmap = uvc_v4l2_mmap,
- .poll = uvc_v4l2_poll,
+ .mmap = vb2_fop_mmap,
+ .poll = vb2_fop_poll,
#ifndef CONFIG_MMU
.get_unmapped_area = uvc_v4l2_get_unmapped_area,
#endif
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 97df5ecd66c9..969eb43a597b 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -473,7 +473,6 @@ struct uvc_video_chain {
struct mutex ctrl_mutex; /* Protects ctrl.info */
- struct v4l2_prio_state prio; /* V4L2 priority state */
u32 caps; /* V4L2 chain-wide caps */
};
@@ -709,16 +708,10 @@ struct uvc_device {
struct uvc_entity *gpio_unit;
};
-enum uvc_handle_state {
- UVC_HANDLE_PASSIVE = 0,
- UVC_HANDLE_ACTIVE = 1,
-};
-
struct uvc_fh {
struct v4l2_fh vfh;
struct uvc_video_chain *chain;
struct uvc_streaming *stream;
- enum uvc_handle_state state;
};
struct uvc_driver {
@@ -783,36 +776,15 @@ struct uvc_entity *uvc_entity_by_id(struct uvc_device *dev, int id);
/* Video buffers queue management. */
int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
int drop_corrupted);
-void uvc_queue_release(struct uvc_video_queue *queue);
-int uvc_request_buffers(struct uvc_video_queue *queue,
- struct v4l2_requestbuffers *rb);
-int uvc_query_buffer(struct uvc_video_queue *queue,
- struct v4l2_buffer *v4l2_buf);
-int uvc_create_buffers(struct uvc_video_queue *queue,
- struct v4l2_create_buffers *v4l2_cb);
-int uvc_queue_buffer(struct uvc_video_queue *queue,
- struct media_device *mdev,
- struct v4l2_buffer *v4l2_buf);
-int uvc_export_buffer(struct uvc_video_queue *queue,
- struct v4l2_exportbuffer *exp);
-int uvc_dequeue_buffer(struct uvc_video_queue *queue,
- struct v4l2_buffer *v4l2_buf, int nonblocking);
-int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type);
-int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type);
void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
struct uvc_buffer *buf);
struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue);
void uvc_queue_buffer_release(struct uvc_buffer *buf);
-int uvc_queue_mmap(struct uvc_video_queue *queue,
- struct vm_area_struct *vma);
-__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
- poll_table *wait);
#ifndef CONFIG_MMU
unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
unsigned long pgoff);
#endif
-int uvc_queue_allocated(struct uvc_video_queue *queue);
static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
{
return vb2_is_streaming(&queue->queue);
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [RFC PATCHv2] uvc: use vb2 ioctl and fop helpers
2021-03-12 10:33 [RFC PATCHv2] uvc: use vb2 ioctl and fop helpers Hans Verkuil
@ 2021-03-12 22:13 ` Laurent Pinchart
0 siblings, 0 replies; 2+ messages in thread
From: Laurent Pinchart @ 2021-03-12 22:13 UTC (permalink / raw)
To: Hans Verkuil; +Cc: Linux Media Mailing List, Ricardo Ribalda Delgado
Hi Hans,
Thank you for the patch.
On Fri, Mar 12, 2021 at 11:33:13AM +0100, Hans Verkuil wrote:
> When uvc was written the vb2 ioctl and file operation helpers didn't exist.
>
> This patch switches uvc over to those helpers, which removes a lot of boilerplate
> code and simplifies VIDIOC_G/S_PRIORITY handling and allows us to drop the
> 'privileges' scheme, since that's now handled inside the vb2 helpers.
>
> This makes it possible for uvc to pass the v4l2-compliance streaming tests.
>
> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> ---
> Changes since v1:
> - use correct queue for metadata
>
> TODO:
> - vb2_fop_get_unmapped_area() should probably be used as well
> - verify suspend/resume
> - for extra bonus points: test if unbind of the driver works while streaming
That's not bonus points, it's something that I've taken great care to
support in the driver, so we really really don't want regressions.
vb2_fop_get_unmapped_area() can wait, the other todo items need to be
addressed.
> ---
> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
> index 30ef2a3110f7..dfaadb5c1bae 100644
> --- a/drivers/media/usb/uvc/uvc_driver.c
> +++ b/drivers/media/usb/uvc/uvc_driver.c
> @@ -1911,7 +1911,6 @@ static struct uvc_video_chain *uvc_alloc_chain(struct uvc_device *dev)
> INIT_LIST_HEAD(&chain->entities);
> mutex_init(&chain->ctrl_mutex);
> chain->dev = dev;
> - v4l2_prio_init(&chain->prio);
>
> return chain;
> }
> @@ -2180,7 +2179,7 @@ int uvc_register_video_device(struct uvc_device *dev,
> vdev->fops = fops;
> vdev->ioctl_ops = ioctl_ops;
> vdev->release = uvc_release;
> - vdev->prio = &stream->chain->prio;
> + vdev->queue = &queue->queue;
> if (type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
> vdev->vfl_dir = VFL_DIR_TX;
> else
> @@ -2541,8 +2540,8 @@ static int __uvc_resume(struct usb_interface *intf, int reset)
> if (stream->intf == intf) {
> ret = uvc_video_resume(stream, reset);
> if (ret < 0)
> - uvc_queue_streamoff(&stream->queue,
> - stream->queue.queue.type);
> + vb2_streamoff(&stream->queue.queue,
> + stream->queue.queue.type);
> return ret;
> }
> }
> diff --git a/drivers/media/usb/uvc/uvc_metadata.c b/drivers/media/usb/uvc/uvc_metadata.c
> index b6279ad7ac84..2f52cdc62929 100644
> --- a/drivers/media/usb/uvc/uvc_metadata.c
> +++ b/drivers/media/usb/uvc/uvc_metadata.c
> @@ -96,7 +96,7 @@ static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
> */
> mutex_lock(&stream->mutex);
>
> - if (uvc_queue_allocated(&stream->queue))
> + if (vb2_is_busy(&stream->queue.queue))
As you've mentioned separately, this should be the meta queue.
> ret = -EBUSY;
> else
> stream->meta.format = fmt->dataformat;
> @@ -164,12 +164,6 @@ int uvc_meta_register(struct uvc_streaming *stream)
>
> 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);
> diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
> index 21a907d32bb7..fba9646c8ba5 100644
> --- a/drivers/media/usb/uvc/uvc_queue.c
> +++ b/drivers/media/usb/uvc/uvc_queue.c
> @@ -247,115 +247,10 @@ int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
> return 0;
> }
>
> -void uvc_queue_release(struct uvc_video_queue *queue)
> -{
> - mutex_lock(&queue->mutex);
> - vb2_queue_release(&queue->queue);
> - mutex_unlock(&queue->mutex);
> -}
> -
> /* -----------------------------------------------------------------------------
> * V4L2 queue operations
> */
>
> -int uvc_request_buffers(struct uvc_video_queue *queue,
> - struct v4l2_requestbuffers *rb)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_reqbufs(&queue->queue, rb);
> - mutex_unlock(&queue->mutex);
> -
> - return ret ? ret : rb->count;
> -}
> -
> -int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_querybuf(&queue->queue, buf);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_create_buffers(struct uvc_video_queue *queue,
> - struct v4l2_create_buffers *cb)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_create_bufs(&queue->queue, cb);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_queue_buffer(struct uvc_video_queue *queue,
> - struct media_device *mdev, struct v4l2_buffer *buf)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_qbuf(&queue->queue, mdev, buf);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_export_buffer(struct uvc_video_queue *queue,
> - struct v4l2_exportbuffer *exp)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_expbuf(&queue->queue, exp);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
> - int nonblocking)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_dqbuf(&queue->queue, buf, nonblocking);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_streamon(&queue->queue, type);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type)
> -{
> - int ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_streamoff(&queue->queue, type);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> -int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
> -{
> - return vb2_mmap(&queue->queue, vma);
> -}
> -
> #ifndef CONFIG_MMU
> unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
> unsigned long pgoff)
> @@ -364,36 +259,10 @@ unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
> }
> #endif
>
> -__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
> - poll_table *wait)
> -{
> - __poll_t ret;
> -
> - mutex_lock(&queue->mutex);
> - ret = vb2_poll(&queue->queue, file, wait);
> - mutex_unlock(&queue->mutex);
> -
> - return ret;
> -}
> -
> /* -----------------------------------------------------------------------------
> *
> */
>
> -/*
> - * Check if buffers have been allocated.
> - */
> -int uvc_queue_allocated(struct uvc_video_queue *queue)
> -{
> - int allocated;
> -
> - mutex_lock(&queue->mutex);
> - allocated = vb2_is_busy(&queue->queue);
> - mutex_unlock(&queue->mutex);
> -
> - return allocated;
> -}
> -
> /*
> * Cancel the video buffers queue.
> *
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> index 252136cc885c..13ff1c9590c2 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -346,17 +346,13 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream,
> return ret;
>
> mutex_lock(&stream->mutex);
> -
> - if (uvc_queue_allocated(&stream->queue)) {
> + if (vb2_is_busy(&stream->queue.queue)) {
> ret = -EBUSY;
> - goto done;
> + } else {
> + stream->ctrl = probe;
> + stream->cur_format = format;
> + stream->cur_frame = frame;
> }
That's probably a matter of personal preferences, but I prefer the goto
done style.
> -
> - stream->ctrl = probe;
> - stream->cur_format = format;
> - stream->cur_frame = frame;
> -
> -done:
> mutex_unlock(&stream->mutex);
> return ret;
> }
> @@ -480,62 +476,6 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
> return 0;
> }
>
> -/* ------------------------------------------------------------------------
> - * Privilege management
> - */
> -
> -/*
> - * Privilege management is the multiple-open implementation basis. The current
> - * implementation is completely transparent for the end-user and doesn't
> - * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
> - * Those ioctls enable finer control on the device (by making possible for a
> - * user to request exclusive access to a device), but are not mature yet.
> - * Switching to the V4L2 priority mechanism might be considered in the future
> - * if this situation changes.
> - *
> - * Each open instance of a UVC device can either be in a privileged or
> - * unprivileged state. Only a single instance can be in a privileged state at
> - * a given time. Trying to perform an operation that requires privileges will
> - * automatically acquire the required privileges if possible, or return -EBUSY
> - * otherwise. Privileges are dismissed when closing the instance or when
> - * freeing the video buffers using VIDIOC_REQBUFS.
> - *
> - * Operations that require privileges are:
> - *
> - * - VIDIOC_S_INPUT
> - * - VIDIOC_S_PARM
> - * - VIDIOC_S_FMT
This is an important change in behaviour, as the V4L2 core doesn't grant
exclusive ownership of the device when any of those three ioctls are
called. Only VIDIOC_REQBUFS does so.
> - * - VIDIOC_REQBUFS
> - */
> -static int uvc_acquire_privileges(struct uvc_fh *handle)
> -{
> - /* Always succeed if the handle is already privileged. */
> - if (handle->state == UVC_HANDLE_ACTIVE)
> - return 0;
> -
> - /* Check if the device already has a privileged handle. */
> - if (atomic_inc_return(&handle->stream->active) != 1) {
> - atomic_dec(&handle->stream->active);
> - return -EBUSY;
> - }
> -
> - handle->state = UVC_HANDLE_ACTIVE;
> - return 0;
> -}
> -
> -static void uvc_dismiss_privileges(struct uvc_fh *handle)
> -{
> - if (handle->state == UVC_HANDLE_ACTIVE)
> - atomic_dec(&handle->stream->active);
> -
> - handle->state = UVC_HANDLE_PASSIVE;
> -}
> -
> -static int uvc_has_privileges(struct uvc_fh *handle)
> -{
> - return handle->state == UVC_HANDLE_ACTIVE;
> -}
> -
> /* ------------------------------------------------------------------------
> * V4L2 file operations
> */
> @@ -578,7 +518,6 @@ static int uvc_v4l2_open(struct file *file)
> v4l2_fh_add(&handle->vfh);
> handle->chain = stream->chain;
> handle->stream = stream;
> - handle->state = UVC_HANDLE_PASSIVE;
> file->private_data = handle;
>
> return 0;
> @@ -591,15 +530,8 @@ static int uvc_v4l2_release(struct file *file)
>
> uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
>
> - /* Only free resources if this is a privileged handle. */
> - if (uvc_has_privileges(handle))
> - uvc_queue_release(&stream->queue);
> -
> /* Release the file handle. */
> - uvc_dismiss_privileges(handle);
> - v4l2_fh_del(&handle->vfh);
> - v4l2_fh_exit(&handle->vfh);
> - kfree(handle);
> + vb2_fop_release(file);
> file->private_data = NULL;
>
> mutex_lock(&stream->dev->lock);
> @@ -693,11 +625,6 @@ static int uvc_ioctl_s_fmt_vid_cap(struct file *file, void *fh,
> {
> struct uvc_fh *handle = fh;
> struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
>
> return uvc_v4l2_set_format(stream, fmt);
> }
> @@ -707,11 +634,6 @@ static int uvc_ioctl_s_fmt_vid_out(struct file *file, void *fh,
> {
> struct uvc_fh *handle = fh;
> struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
>
> return uvc_v4l2_set_format(stream, fmt);
> }
> @@ -736,124 +658,6 @@ static int uvc_ioctl_try_fmt_vid_out(struct file *file, void *fh,
> return uvc_v4l2_try_format(stream, fmt, &probe, NULL, NULL);
> }
>
> -static int uvc_ioctl_reqbufs(struct file *file, void *fh,
> - struct v4l2_requestbuffers *rb)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
> -
> - mutex_lock(&stream->mutex);
> - ret = uvc_request_buffers(&stream->queue, rb);
> - mutex_unlock(&stream->mutex);
This (and most of the other changes) introduce a race condition, as you
now only use the queue mutex to serialize the buffer-related ioctls,
while the other ioctls are protected by the stream mutex. Those are two
different mutexes.
> - if (ret < 0)
> - return ret;
> -
> - if (ret == 0)
> - uvc_dismiss_privileges(handle);
> -
> - return 0;
> -}
> -
> -static int uvc_ioctl_querybuf(struct file *file, void *fh,
> - struct v4l2_buffer *buf)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - return uvc_query_buffer(&stream->queue, buf);
> -}
> -
> -static int uvc_ioctl_qbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - return uvc_queue_buffer(&stream->queue,
> - stream->vdev.v4l2_dev->mdev, buf);
> -}
> -
> -static int uvc_ioctl_expbuf(struct file *file, void *fh,
> - struct v4l2_exportbuffer *exp)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - return uvc_export_buffer(&stream->queue, exp);
> -}
> -
> -static int uvc_ioctl_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - return uvc_dequeue_buffer(&stream->queue, buf,
> - file->f_flags & O_NONBLOCK);
> -}
> -
> -static int uvc_ioctl_create_bufs(struct file *file, void *fh,
> - struct v4l2_create_buffers *cb)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
> -
> - return uvc_create_buffers(&stream->queue, cb);
> -}
> -
> -static int uvc_ioctl_streamon(struct file *file, void *fh,
> - enum v4l2_buf_type type)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - mutex_lock(&stream->mutex);
> - ret = uvc_queue_streamon(&stream->queue, type);
> - mutex_unlock(&stream->mutex);
> -
> - return ret;
> -}
> -
> -static int uvc_ioctl_streamoff(struct file *file, void *fh,
> - enum v4l2_buf_type type)
> -{
> - struct uvc_fh *handle = fh;
> - struct uvc_streaming *stream = handle->stream;
> -
> - if (!uvc_has_privileges(handle))
> - return -EBUSY;
> -
> - mutex_lock(&stream->mutex);
> - uvc_queue_streamoff(&stream->queue, type);
> - mutex_unlock(&stream->mutex);
> -
> - return 0;
> -}
> -
> static int uvc_ioctl_enum_input(struct file *file, void *fh,
> struct v4l2_input *input)
> {
> @@ -921,13 +725,12 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input)
> static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input)
> {
> struct uvc_fh *handle = fh;
> + struct uvc_streaming *stream = handle->stream;
> struct uvc_video_chain *chain = handle->chain;
> - int ret;
> u32 i;
>
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
> + if (vb2_is_busy(&stream->queue.queue))
> + return -EBUSY;
>
> if (chain->selector == NULL ||
> (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
> @@ -1187,11 +990,6 @@ static int uvc_ioctl_s_parm(struct file *file, void *fh,
> {
> struct uvc_fh *handle = fh;
> struct uvc_streaming *stream = handle->stream;
> - int ret;
> -
> - ret = uvc_acquire_privileges(handle);
> - if (ret < 0)
> - return ret;
>
> return uvc_v4l2_set_streamparm(stream, parm);
> }
> @@ -1459,36 +1257,6 @@ static long uvc_v4l2_compat_ioctl32(struct file *file,
> }
> #endif
>
> -static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
> - size_t count, loff_t *ppos)
> -{
> - struct uvc_fh *handle = file->private_data;
> - struct uvc_streaming *stream = handle->stream;
> -
> - uvc_dbg(stream->dev, CALLS, "%s: not implemented\n", __func__);
> - return -EINVAL;
> -}
> -
> -static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
> -{
> - struct uvc_fh *handle = file->private_data;
> - struct uvc_streaming *stream = handle->stream;
> -
> - uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
> -
> - return uvc_queue_mmap(&stream->queue, vma);
> -}
> -
> -static __poll_t uvc_v4l2_poll(struct file *file, poll_table *wait)
> -{
> - struct uvc_fh *handle = file->private_data;
> - struct uvc_streaming *stream = handle->stream;
> -
> - uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
> -
> - return uvc_queue_poll(&stream->queue, file, wait);
> -}
> -
> #ifndef CONFIG_MMU
> static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
> unsigned long addr, unsigned long len, unsigned long pgoff,
> @@ -1513,14 +1281,15 @@ const struct v4l2_ioctl_ops uvc_ioctl_ops = {
> .vidioc_s_fmt_vid_out = uvc_ioctl_s_fmt_vid_out,
> .vidioc_try_fmt_vid_cap = uvc_ioctl_try_fmt_vid_cap,
> .vidioc_try_fmt_vid_out = uvc_ioctl_try_fmt_vid_out,
> - .vidioc_reqbufs = uvc_ioctl_reqbufs,
> - .vidioc_querybuf = uvc_ioctl_querybuf,
> - .vidioc_qbuf = uvc_ioctl_qbuf,
> - .vidioc_expbuf = uvc_ioctl_expbuf,
> - .vidioc_dqbuf = uvc_ioctl_dqbuf,
> - .vidioc_create_bufs = uvc_ioctl_create_bufs,
> - .vidioc_streamon = uvc_ioctl_streamon,
> - .vidioc_streamoff = uvc_ioctl_streamoff,
> + .vidioc_reqbufs = vb2_ioctl_reqbufs,
> + .vidioc_querybuf = vb2_ioctl_querybuf,
> + .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
> + .vidioc_qbuf = vb2_ioctl_qbuf,
> + .vidioc_expbuf = vb2_ioctl_expbuf,
> + .vidioc_dqbuf = vb2_ioctl_dqbuf,
> + .vidioc_create_bufs = vb2_ioctl_create_bufs,
> + .vidioc_streamon = vb2_ioctl_streamon,
> + .vidioc_streamoff = vb2_ioctl_streamoff,
> .vidioc_enum_input = uvc_ioctl_enum_input,
> .vidioc_g_input = uvc_ioctl_g_input,
> .vidioc_s_input = uvc_ioctl_s_input,
> @@ -1550,9 +1319,8 @@ const struct v4l2_file_operations uvc_fops = {
> #ifdef CONFIG_COMPAT
> .compat_ioctl32 = uvc_v4l2_compat_ioctl32,
> #endif
> - .read = uvc_v4l2_read,
> - .mmap = uvc_v4l2_mmap,
> - .poll = uvc_v4l2_poll,
> + .mmap = vb2_fop_mmap,
> + .poll = vb2_fop_poll,
> #ifndef CONFIG_MMU
> .get_unmapped_area = uvc_v4l2_get_unmapped_area,
> #endif
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 97df5ecd66c9..969eb43a597b 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -473,7 +473,6 @@ struct uvc_video_chain {
>
> struct mutex ctrl_mutex; /* Protects ctrl.info */
>
> - struct v4l2_prio_state prio; /* V4L2 priority state */
> u32 caps; /* V4L2 chain-wide caps */
> };
>
> @@ -709,16 +708,10 @@ struct uvc_device {
> struct uvc_entity *gpio_unit;
> };
>
> -enum uvc_handle_state {
> - UVC_HANDLE_PASSIVE = 0,
> - UVC_HANDLE_ACTIVE = 1,
> -};
> -
> struct uvc_fh {
> struct v4l2_fh vfh;
> struct uvc_video_chain *chain;
> struct uvc_streaming *stream;
> - enum uvc_handle_state state;
> };
>
> struct uvc_driver {
> @@ -783,36 +776,15 @@ struct uvc_entity *uvc_entity_by_id(struct uvc_device *dev, int id);
> /* Video buffers queue management. */
> int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
> int drop_corrupted);
> -void uvc_queue_release(struct uvc_video_queue *queue);
> -int uvc_request_buffers(struct uvc_video_queue *queue,
> - struct v4l2_requestbuffers *rb);
> -int uvc_query_buffer(struct uvc_video_queue *queue,
> - struct v4l2_buffer *v4l2_buf);
> -int uvc_create_buffers(struct uvc_video_queue *queue,
> - struct v4l2_create_buffers *v4l2_cb);
> -int uvc_queue_buffer(struct uvc_video_queue *queue,
> - struct media_device *mdev,
> - struct v4l2_buffer *v4l2_buf);
> -int uvc_export_buffer(struct uvc_video_queue *queue,
> - struct v4l2_exportbuffer *exp);
> -int uvc_dequeue_buffer(struct uvc_video_queue *queue,
> - struct v4l2_buffer *v4l2_buf, int nonblocking);
> -int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type);
> -int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type);
> void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
> struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
> struct uvc_buffer *buf);
> struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue);
> void uvc_queue_buffer_release(struct uvc_buffer *buf);
> -int uvc_queue_mmap(struct uvc_video_queue *queue,
> - struct vm_area_struct *vma);
> -__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
> - poll_table *wait);
> #ifndef CONFIG_MMU
> unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
> unsigned long pgoff);
> #endif
> -int uvc_queue_allocated(struct uvc_video_queue *queue);
> static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
> {
> return vb2_is_streaming(&queue->queue);
--
Regards,
Laurent Pinchart
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2021-03-12 22:14 UTC | newest]
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2021-03-12 10:33 [RFC PATCHv2] uvc: use vb2 ioctl and fop helpers Hans Verkuil
2021-03-12 22:13 ` Laurent Pinchart
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