[media] vb2: stop_streaming should return void

The vb2 core ignores any return code from the stop_streaming op.
And there really isn't anything it can do anyway in case of an error.
So change the return type to void and update any drivers that implement it.

The int return gave drivers the idea that this operation could actually
fail, but that's really not the case.

The pwc amd sdr-msi3101 drivers both had this construction:

        if (mutex_lock_interruptible(&s->v4l2_lock))
                return -ERESTARTSYS;

This has been updated to just call mutex_lock(). The stop_streaming op
expects this to really stop streaming and I very much doubt this will
work reliably if stop_streaming just returns without really stopping the
DMA.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pawel Osciak <pawel@osciak.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

1 files changed, 2 insertions, 5 deletions

diff --git a/drivers/media/usb/pwc/pwc-if.c b/drivers/media/usb/pwc/pwc-if.c
index 84a6720b1d00..a73b0bced96f 100644
--- a/drivers/media/usb/pwc/pwc-if.c
+++ b/drivers/media/usb/pwc/pwc-if.c
@@ -681,12 +681,11 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count)
         return r;
 }
 
-static int stop_streaming(struct vb2_queue *vq)
+static void stop_streaming(struct vb2_queue *vq)
 {
         struct pwc_device *pdev = vb2_get_drv_priv(vq);
 
-        if (mutex_lock_interruptible(&pdev->v4l2_lock))
-                return -ERESTARTSYS;
+        mutex_lock(&pdev->v4l2_lock);
         if (pdev->udev) {
                 pwc_set_leds(pdev, 0, 0);
                 pwc_camera_power(pdev, 0);
@@ -695,8 +694,6 @@ static int stop_streaming(struct vb2_queue *vq)
 
         pwc_cleanup_queued_bufs(pdev);
         mutex_unlock(&pdev->v4l2_lock);
-
-        return 0;
 }
 
 static struct vb2_ops pwc_vb_queue_ops = {