redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

[media] saa7164: fix poll bugs

Browse source 
- poll doesn't return negative values, so you can't return -EINVAL.
  Instead return POLLERR.
- poll can't be called if !video_is_registered(), so this test can
  be dropped.
- poll can never do a blocking wait, so remove that check.
- poll shouldn't attempt to start streaming if the caller isn't interested
  in read events.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
Hans Verkuil 2015-08-28 08:48:28 -03:00 committed by Mauro Carvalho Chehab
parent d6d3fe2fe1
commit 45053edc05
1 changed files with 4 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
drivers/media/pci/saa7164/saa7164-encoder.c
View file

@ -915,6 +915,7 @@ err:
static unsigned int fops_poll(struct file *file, poll_table *wait)
{
unsigned long req_events = poll_requested_events(wait);
struct saa7164_encoder_fh *fh =
(struct saa7164_encoder_fh *)file->private_data;
struct saa7164_port *port = fh->port;
@ -928,26 +929,18 @@ static unsigned int fops_poll(struct file *file, poll_table *wait)
saa7164_histogram_update(&port->poll_interval,
port->last_poll_msecs_diff);
if (!video_is_registered(port->v4l_device))
return -EIO;
if (!(req_events & (POLLIN | POLLRDNORM)))
return mask;
if (atomic_cmpxchg(&fh->v4l_reading, 0, 1) == 0) {
if (atomic_inc_return(&port->v4l_reader_count) == 1) {
if (saa7164_encoder_initialize(port) < 0)
return -EINVAL;
return POLLERR;
saa7164_encoder_start_streaming(port);
msleep(200);
}
}
/* blocking wait for buffer */
if ((file->f_flags & O_NONBLOCK) == 0) {
if (wait_event_interruptible(port->wait_read,
saa7164_enc_next_buf(port))) {
return -ERESTARTSYS;
}
}
/* Pull the first buffer from the used list */
if (!list_empty(&port->list_buf_used.list))
mask |= POLLIN | POLLRDNORM;