LF-4830 media: isi_m2m: fix gstreamer pipeline can not work on second open

Command to reproduce:
gst-launch-1.0 v4l2src device=/dev/video3 ! video/x-raw,format=YUY2 !\
v4l2convert ! video/x-raw,format=RGB ! videoconvert !\
waylandsink --no-position

After do Ctrl+C to exit, then run the same command again,
pipeline cannot work normally.

This can actually be reproduced with just do cat command, running the
command a few times (video2 is m2m device node, video3 is sensor device node):
$ cat /dev/video2
cat: /dev/video2: Invalid argument

And this patch is enhancment for LF-4315.

root cause:
In mxc_isi_m2m_open() if the refcnt is not 0, return -EBUSY,
but refcnt increased. If refcnt > 1, close function will never really release
device resource (the resource can be really released only if refcnt = 0).
This leaded to the device busy and can not be used again.

So only increase refcnt on success in mxc_isi_m2m_open() can prevent device
resource busy issue.

Signed-off-by: Alice Yuan <alice.yuan@nxp.com>
Reviewed-by：Robby Cai <robby.cai@nxp.com>

0 files changed, 0 insertions, 0 deletions