the application to stop streaming to reset the hardware state.
It is not allowed to mix queuing requests with queuing buffers directly
-(without a request). ``EPERM`` will be returned if the first buffer was
+(without a request). ``EBUSY`` will be returned if the first buffer was
queued directly and you next try to queue a request, or vice versa.
A request must contain at least one buffer, otherwise this ioctl will
:ref:`Generic Error Codes <gen-errors>` chapter.
EBUSY
- The request was already queued.
-EPERM
- The application queued the first buffer directly, but later attempted
- to use a request. It is not permitted to mix the two APIs.
+ The request was already queued or the application queued the first
+ buffer directly, but later attempted to use a request. It is not permitted
+ to mix the two APIs.
ENOENT
The request did not contain any buffers. All requests are required
to have at least one buffer. This can also be returned if required
.. caution::
For :ref:`memory-to-memory devices <codec>` you can use requests only for
output buffers, not for capture buffers. Attempting to add a capture buffer
- to a request will result in an ``EPERM`` error.
+ to a request will result in an ``EACCES`` error.
If the request contains parameters for multiple entities, individual drivers may
synchronize so the requested pipeline's topology is applied before the buffers
whichever method is used first locks this in place until
:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` is called or the device is
:ref:`closed <func-close>`. Attempts to directly queue a buffer when earlier
- a buffer was queued via a request or vice versa will result in an ``EPERM``
+ a buffer was queued via a request or vice versa will result in an ``EBUSY``
error.
Controls can still be set without a request and are applied immediately,
:ref:`ioctl VIDIOC_QBUF <VIDIOC_QBUF>` and ignored by other ioctls.
Applications should not set ``V4L2_BUF_FLAG_REQUEST_FD`` for any ioctls
other than :ref:`VIDIOC_QBUF <VIDIOC_QBUF>`.
- If the device does not support requests, then ``EPERM`` will be returned.
+ If the device does not support requests, then ``EACCES`` will be returned.
If requests are supported but an invalid request file descriptor is
given, then ``EINVAL`` will be returned.
then the controls are not applied immediately when calling
:ref:`VIDIOC_S_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>`, but instead are applied by
the driver for the buffer associated with the same request.
-If the device does not support requests, then ``EPERM`` will be returned.
+If the device does not support requests, then ``EACCES`` will be returned.
If requests are supported but an invalid request file descriptor is given,
then ``EINVAL`` will be returned.
these controls have to be retrieved from a request or tried/set for
a request. In the latter case the ``request_fd`` field contains the
file descriptor of the request that should be used. If the device
- does not support requests, then ``EPERM`` will be returned.
+ does not support requests, then ``EACCES`` will be returned.
.. note::
- ``request_fd``
- File descriptor of the request to be used by this operation. Only
valid if ``which`` is set to ``V4L2_CTRL_WHICH_REQUEST_VAL``.
- If the device does not support requests, then ``EPERM`` will be returned.
+ If the device does not support requests, then ``EACCES`` will be returned.
If requests are supported but an invalid request file descriptor is
given, then ``EINVAL`` will be returned.
* - __u32
control, or to get a control from a request that has not yet been
completed.
-EPERM
- The ``which`` field was set to ``V4L2_CTRL_WHICH_REQUEST_VAL`` but the
+ Or the ``which`` field was set to ``V4L2_CTRL_WHICH_REQUEST_VAL`` but the
device does not support requests.
until the request itself is queued. Also, the driver will apply any
settings associated with the request for this buffer. This field will
be ignored unless the ``V4L2_BUF_FLAG_REQUEST_FD`` flag is set.
-If the device does not support requests, then ``EPERM`` will be returned.
+If the device does not support requests, then ``EACCES`` will be returned.
If requests are supported but an invalid request file descriptor is given,
then ``EINVAL`` will be returned.
.. caution::
It is not allowed to mix queuing requests with queuing buffers directly.
- ``EPERM`` will be returned if the first buffer was queued directly and
+ ``EBUSY`` will be returned if the first buffer was queued directly and
then the application tries to queue a request, or vice versa.
For :ref:`memory-to-memory devices <codec>` you can specify the
``request_fd`` only for output buffers, not for capture buffers. Attempting
- to specify this for a capture buffer will result in an ``EPERM`` error.
+ to specify this for a capture buffer will result in an ``EACCES`` error.
Applications call the ``VIDIOC_DQBUF`` ioctl to dequeue a filled
(capturing) or displayed (output) buffer from the driver's outgoing
codecs if a buffer with the ``V4L2_BUF_FLAG_LAST`` was already
dequeued and no new buffers are expected to become available.
-EPERM
+EACCES
The ``V4L2_BUF_FLAG_REQUEST_FD`` flag was set but the device does not
- support requests. Or the first buffer was queued via a request, but
- the application now tries to queue it directly, or vice versa (it is
- not permitted to mix the two APIs). Or an attempt is made to queue a
- CAPTURE buffer to a request for a :ref:`memory-to-memory device <codec>`.
+ support requests for the given buffer type.
+
+EBUSY
+ The first buffer was queued via a request, but the application now tries
+ to queue it directly, or vice versa (it is not permitted to mix the two
+ APIs).
(!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
q->uses_requests)) {
dprintk(1, "queue in wrong mode (qbuf vs requests)\n");
- return -EPERM;
+ return -EBUSY;
}
if (req) {
if (!(b->flags & V4L2_BUF_FLAG_REQUEST_FD)) {
if (q->uses_requests) {
dprintk(1, "%s: queue uses requests\n", opname);
- return -EPERM;
+ return -EBUSY;
}
return 0;
- } else if (q->uses_qbuf || !q->supports_requests) {
+ } else if (!q->supports_requests) {
+ dprintk(1, "%s: queue does not support requests\n", opname);
+ return -EACCES;
+ } else if (q->uses_qbuf) {
dprintk(1, "%s: queue does not use requests\n", opname);
- return -EPERM;
+ return -EBUSY;
}
/*
if (!mdev || !mdev->ops ||
!mdev->ops->req_validate || !mdev->ops->req_queue)
- return ERR_PTR(-EPERM);
+ return ERR_PTR(-EACCES);
filp = fget(request_fd);
if (!filp)
int ret = -EBUSY;
if (WARN_ON(!ops->release))
- return -EPERM;
+ return -EACCES;
spin_lock_irqsave(&req->lock, flags);
* Get the request represented by @request_fd that is owned
* by the media device.
*
- * Return a -EPERM error pointer if requests are not supported
+ * Return a -EACCES error pointer if requests are not supported
* by this driver. Return -EINVAL if the request was not found.
* Return the pointer to the request if found: the caller will
* have to call @media_request_put when it finished using the
static inline struct media_request *
media_request_get_by_fd(struct media_device *mdev, int request_fd)
{
- return ERR_PTR(-EPERM);
+ return ERR_PTR(-EACCES);
}
#endif