[media] pwc: do not start isoc stream on /dev/video open

pwc was starting streaming on /dev/video# open rather then on STREAM_ON. Now
that the v4l1 compat code is removed from the pwc driver there is no reason
left to do this. So this patch changes the pwc driver to delay starting
the isoc stream (and thus using valuable usb bandwidth) until the application
does a STREAM_ON

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/media/video/pwc/pwc-v4l.c b/drivers/media/video/pwc/pwc-v4l.c
index 7061a03f5cf1..2ef1668638f9 100644
--- a/drivers/media/video/pwc/pwc-v4l.c
+++ b/drivers/media/video/pwc/pwc-v4l.c
@@ -309,7 +309,10 @@ static int pwc_vidioc_set_fmt(struct pwc_device *pdev, struct v4l2_format *f)
             pixelformat != V4L2_PIX_FMT_PWC2)
                 return -EINVAL;
 
-        PWC_DEBUG_IOCTL("Try to change format to: width=%d height=%d fps=%d "
+        if (pdev->iso_init)
+                return -EBUSY;
+
+        PWC_DEBUG_IOCTL("Trying to set format to: width=%d height=%d fps=%d "
                         "compression=%d snapshot=%d format=%c%c%c%c\n",
                         f->fmt.pix.width, f->fmt.pix.height, fps,
                         compression, snapshot,
@@ -318,14 +321,14 @@ static int pwc_vidioc_set_fmt(struct pwc_device *pdev, struct v4l2_format *f)
                         (pixelformat>>16)&255,
                         (pixelformat>>24)&255);
 
-        ret = pwc_try_video_mode(pdev,
+        ret = pwc_set_video_mode(pdev,
                                  f->fmt.pix.width,
                                  f->fmt.pix.height,
                                  fps,
                                  compression,
                                  snapshot);
 
-        PWC_DEBUG_IOCTL("pwc_try_video_mode(), return=%d\n", ret);
+        PWC_DEBUG_IOCTL("pwc_set_video_mode(), return=%d\n", ret);
 
         if (ret)
                 return ret;
@@ -882,9 +885,7 @@ long pwc_video_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
                 case VIDIOC_STREAMON:
                 {
-                        /* WARNING: pwc_try_video_mode() called pwc_isoc_init */
-                        pwc_isoc_init(pdev);
-                        return 0;
+                        return pwc_isoc_init(pdev);
                 }
 
                 case VIDIOC_STREAMOFF: