/**
* vb2_poll() - implements poll userspace operation
* @q: videobuf2 queue
* @file: file argument passed to the poll file operation handler
* @wait: wait argument passed to the poll file operation handler
*
* This function implements poll file operation handler for a driver.
* For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
* be informed that the file descriptor of a video device is available for
* reading.
* For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
* will be reported as available for writing.
*
* If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
* pending events.
*
* The return values from this function are intended to be directly returned
* from poll handler in driver.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
{
struct video_device *vfd = video_devdata(file);
unsigned long req_events = poll_requested_events(wait);
unsigned int res = 0;
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
struct v4l2_fh *fh = file->private_data;
if (v4l2_event_pending(fh))
res = POLLPRI;
else if (req_events & POLLPRI)
poll_wait(file, &fh->wait, wait);
}
/*
* For compatibility with vb1: if QBUF hasn't been called yet, then
* return POLLERR as well. This only affects capture queues, output
* queues will always initialize waiting_for_buffers to false.
*/
if (q->waiting_for_buffers && (req_events & (POLLIN | POLLRDNORM)))
return POLLERR;
return res | vb2_core_poll(q, file, wait);
}
unsigned int videobuf_poll_stream(struct file *file,
struct videobuf_queue *q,
poll_table *wait)
{
unsigned long req_events = poll_requested_events(wait);
struct videobuf_buffer *buf = NULL;
unsigned int rc = 0;
videobuf_queue_lock(q);
if (q->streaming) {
if (!list_empty(&q->stream))
buf = list_entry(q->stream.next,
struct videobuf_buffer, stream);
} else if (req_events & (POLLIN | POLLRDNORM)) {
__poll_t videobuf_poll_stream(struct file *file,
struct videobuf_queue *q,
poll_table *wait)
{
__poll_t req_events = poll_requested_events(wait);
struct videobuf_buffer *buf = NULL;
__poll_t rc = 0;
poll_wait(file, &buf->done, wait);
videobuf_queue_lock(q);
if (q->streaming) {
if (!list_empty(&q->stream))
buf = list_entry(q->stream.next,
struct videobuf_buffer, stream);
} else if (req_events & (EPOLLIN | EPOLLRDNORM)) {
/**
* mei_poll - the poll function
*
* @file: pointer to file structure
* @wait: pointer to poll_table structure
*
* Return: poll mask
*/
static __poll_t mei_poll(struct file *file, poll_table *wait)
{
__poll_t req_events = poll_requested_events(wait);
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
__poll_t mask = 0;
bool notify_en;
if (WARN_ON(!cl || !cl->dev))
return EPOLLERR;
dev = cl->dev;
mutex_lock(&dev->device_lock);
notify_en = cl->notify_en && (req_events & EPOLLPRI);
if (dev->dev_state != MEI_DEV_ENABLED ||
!mei_cl_is_connected(cl)) {
mask = EPOLLERR;
goto out;
}
if (notify_en) {
poll_wait(file, &cl->ev_wait, wait);
if (cl->notify_ev)
mask |= EPOLLPRI;
}
if (req_events & (EPOLLIN | EPOLLRDNORM)) {
poll_wait(file, &cl->rx_wait, wait);
if (!list_empty(&cl->rd_completed))
mask |= EPOLLIN | EPOLLRDNORM;
else
mei_cl_read_start(cl, mei_cl_mtu(cl), file);
}
if (req_events & (POLLOUT | POLLWRNORM)) {
poll_wait(file, &cl->tx_wait, wait);
if (cl->tx_cb_queued < dev->tx_queue_limit)
mask |= POLLOUT | POLLWRNORM;
}
out:
mutex_unlock(&dev->device_lock);
return mask;
}
/**
* mei_poll - the poll function
*
* @file: pointer to file structure
* @wait: pointer to poll_table structure
*
* Return: poll mask
*/
static unsigned int mei_poll(struct file *file, poll_table *wait)
{
unsigned long req_events = poll_requested_events(wait);
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
unsigned int mask = 0;
bool notify_en;
if (WARN_ON(!cl || !cl->dev))
return POLLERR;
dev = cl->dev;
mutex_lock(&dev->device_lock);
notify_en = cl->notify_en && (req_events & POLLPRI);
if (dev->dev_state != MEI_DEV_ENABLED ||
!mei_cl_is_connected(cl)) {
mask = POLLERR;
goto out;
}
if (notify_en) {
poll_wait(file, &cl->ev_wait, wait);
if (cl->notify_ev)
mask |= POLLPRI;
}
if (cl == &dev->iamthif_cl) {
mask |= mei_amthif_poll(file, wait);
goto out;
}
if (req_events & (POLLIN | POLLRDNORM)) {
poll_wait(file, &cl->rx_wait, wait);
if (!list_empty(&cl->rd_completed))
mask |= POLLIN | POLLRDNORM;
else
mei_cl_read_start(cl, mei_cl_mtu(cl), file);
}
out:
mutex_unlock(&dev->device_lock);
return mask;
}
/**
* vb2_poll() - implements poll userspace operation
* @q: videobuf2 queue
* @file: file argument passed to the poll file operation handler
* @wait: wait argument passed to the poll file operation handler
*
* This function implements poll file operation handler for a driver.
* For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
* be informed that the file descriptor of a video device is available for
* reading.
* For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
* will be reported as available for writing.
*
* If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
* pending events.
*
* The return values from this function are intended to be directly returned
* from poll handler in driver.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
{
struct video_device *vfd = video_devdata(file);
unsigned long req_events = poll_requested_events(wait);
unsigned int res = 0;
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
struct v4l2_fh *fh = file->private_data;
if (v4l2_event_pending(fh))
res = POLLPRI;
else if (req_events & POLLPRI)
poll_wait(file, &fh->wait, wait);
}
return res | vb2_core_poll(q, file, wait);
}
/*
* si470x_fops_poll - poll RDS data
*/
static unsigned int si470x_fops_poll(struct file *file,
struct poll_table_struct *pts)
{
struct si470x_device *radio = video_drvdata(file);
unsigned long req_events = poll_requested_events(pts);
int retval = v4l2_ctrl_poll(file, pts);
if (req_events & (POLLIN | POLLRDNORM)) {
/* switch on rds reception */
if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
si470x_rds_on(radio);
poll_wait(file, &radio->read_queue, pts);
if (radio->rd_index != radio->wr_index)
retval |= POLLIN | POLLRDNORM;
}
return retval;
}
__poll_t ivtv_v4l2_enc_poll(struct file *filp, poll_table *wait)
{
__poll_t req_events = poll_requested_events(wait);
struct ivtv_open_id *id = fh2id(filp->private_data);
struct ivtv *itv = id->itv;
struct ivtv_stream *s = &itv->streams[id->type];
int eof = test_bit(IVTV_F_S_STREAMOFF, &s->s_flags);
__poll_t res = 0;
/* Start a capture if there is none */
if (!eof && !test_bit(IVTV_F_S_STREAMING, &s->s_flags) &&
s->type != IVTV_ENC_STREAM_TYPE_RAD &&
(req_events & (EPOLLIN | EPOLLRDNORM))) {
int rc;
mutex_lock(&itv->serialize_lock);
rc = ivtv_start_capture(id);
mutex_unlock(&itv->serialize_lock);
if (rc) {
IVTV_DEBUG_INFO("Could not start capture for %s (%d)\n",
s->name, rc);
return EPOLLERR;
}
IVTV_DEBUG_FILE("Encoder poll started capture\n");
}
/* add stream's waitq to the poll list */
IVTV_DEBUG_HI_FILE("Encoder poll\n");
poll_wait(filp, &s->waitq, wait);
if (v4l2_event_pending(&id->fh))
res |= EPOLLPRI;
else
poll_wait(filp, &id->fh.wait, wait);
if (s->q_full.length || s->q_io.length)
return res | EPOLLIN | EPOLLRDNORM;
if (eof)
return res | EPOLLHUP;
return res;
}
/**
* v4l2_m2m_poll() - poll replacement, for destination buffers only
*
* Call from the driver's poll() function. Will poll both queues. If a buffer
* is available to dequeue (with dqbuf) from the source queue, this will
* indicate that a non-blocking write can be performed, while read will be
* returned in case of the destination queue.
*/
unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct poll_table_struct *wait)
{
struct video_device *vfd = video_devdata(file);
unsigned long req_events = poll_requested_events(wait);
struct vb2_queue *src_q, *dst_q;
struct vb2_buffer *src_vb = NULL, *dst_vb = NULL;
unsigned int rc = 0;
unsigned long flags;
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
struct v4l2_fh *fh = file->private_data;
if (v4l2_event_pending(fh))
rc = POLLPRI;
else if (req_events & POLLPRI)
poll_wait(file, &fh->wait, wait);
if (!(req_events & (POLLOUT | POLLWRNORM | POLLIN | POLLRDNORM)))
return rc;
}
src_q = v4l2_m2m_get_src_vq(m2m_ctx);
dst_q = v4l2_m2m_get_dst_vq(m2m_ctx);
/*
* There has to be at least one buffer queued on each queued_list, which
* means either in driver already or waiting for driver to claim it
* and start processing.
*/
if ((!src_q->streaming || list_empty(&src_q->queued_list))
&& (!dst_q->streaming || list_empty(&dst_q->queued_list))) {
rc |= POLLERR;
goto end;
}
if (m2m_ctx->m2m_dev->m2m_ops->unlock)
m2m_ctx->m2m_dev->m2m_ops->unlock(m2m_ctx->priv);
poll_wait(file, &src_q->done_wq, wait);
poll_wait(file, &dst_q->done_wq, wait);
if (m2m_ctx->m2m_dev->m2m_ops->lock)
m2m_ctx->m2m_dev->m2m_ops->lock(m2m_ctx->priv);
spin_lock_irqsave(&src_q->done_lock, flags);
if (!list_empty(&src_q->done_list))
src_vb = list_first_entry(&src_q->done_list, struct vb2_buffer,
done_entry);
if (src_vb && (src_vb->state == VB2_BUF_STATE_DONE
|| src_vb->state == VB2_BUF_STATE_ERROR))
rc |= POLLOUT | POLLWRNORM;
spin_unlock_irqrestore(&src_q->done_lock, flags);
spin_lock_irqsave(&dst_q->done_lock, flags);
if (!list_empty(&dst_q->done_list))
dst_vb = list_first_entry(&dst_q->done_list, struct vb2_buffer,
done_entry);
if (dst_vb && (dst_vb->state == VB2_BUF_STATE_DONE
|| dst_vb->state == VB2_BUF_STATE_ERROR))
rc |= POLLIN | POLLRDNORM;
spin_unlock_irqrestore(&dst_q->done_lock, flags);
end:
return rc;
}
/**
* vb2_poll() - implements poll userspace operation
* @q: videobuf2 queue
* @file: file argument passed to the poll file operation handler
* @wait: wait argument passed to the poll file operation handler
*
* This function implements poll file operation handler for a driver.
* For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
* be informed that the file descriptor of a video device is available for
* reading.
* For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
* will be reported as available for writing.
*
* If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
* pending events.
*
* The return values from this function are intended to be directly returned
* from poll handler in driver.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
{
struct video_device *vfd = video_devdata(file);
unsigned long req_events = poll_requested_events(wait);
struct vb2_buffer *vb = NULL;
unsigned int res = 0;
unsigned long flags;
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
struct v4l2_fh *fh = file->private_data;
if (v4l2_event_pending(fh))
res = POLLPRI;
else if (req_events & POLLPRI)
poll_wait(file, &fh->wait, wait);
}
if (!q->is_output && !(req_events & (POLLIN | POLLRDNORM)))
return res;
if (q->is_output && !(req_events & (POLLOUT | POLLWRNORM)))
return res;
/*
* Start file I/O emulator only if streaming API has not been used yet.
*/
if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) {
if (!q->is_output && (q->io_modes & VB2_READ) &&
(req_events & (POLLIN | POLLRDNORM))) {
if (__vb2_init_fileio(q, 1))
return res | POLLERR;
}
if (q->is_output && (q->io_modes & VB2_WRITE) &&
(req_events & (POLLOUT | POLLWRNORM))) {
if (__vb2_init_fileio(q, 0))
return res | POLLERR;
/*
* Write to OUTPUT queue can be done immediately.
*/
return res | POLLOUT | POLLWRNORM;
}
}
/*
* There is nothing to wait for if the queue isn't streaming, or if the
* error flag is set.
*/
if (!vb2_is_streaming(q) || q->error)
return res | POLLERR;
/*
* For compatibility with vb1: if QBUF hasn't been called yet, then
* return POLLERR as well. This only affects capture queues, output
* queues will always initialize waiting_for_buffers to false.
*/
if (q->waiting_for_buffers)
return res | POLLERR;
/*
* For output streams you can call write() as long as there are fewer
* buffers queued than there are buffers available.
*/
if (q->is_output && q->fileio && q->queued_count < q->num_buffers)
return res | POLLOUT | POLLWRNORM;
if (list_empty(&q->done_list)) {
/*
* If the last buffer was dequeued from a capture queue,
* return immediately. DQBUF will return -EPIPE.
*/
if (q->last_buffer_dequeued)
return res | POLLIN | POLLRDNORM;
poll_wait(file, &q->done_wq, wait);
}
/*
* Take first buffer available for dequeuing.
*/
spin_lock_irqsave(&q->done_lock, flags);
if (!list_empty(&q->done_list))
vb = list_first_entry(&q->done_list, struct vb2_buffer,
done_entry);
spin_unlock_irqrestore(&q->done_lock, flags);
if (vb && (vb->state == VB2_BUF_STATE_DONE
|| vb->state == VB2_BUF_STATE_ERROR)) {
return (q->is_output) ?
res | POLLOUT | POLLWRNORM :
res | POLLIN | POLLRDNORM;
}
return res;
}
