Commit cd9d9377 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: v4l2-ioctl.c: readbuffers depends on V4L2_CAP_READWRITE 



If V4L2_CAP_READWRITE is not set, then readbuffers must be set to 0,
otherwise v4l2-compliance will complain.

A note on the Fixes tag below: this patch does not really fix that commit,
but it can be applied from that commit onwards. For older code there is no
guarantee that device_caps is set, so even though this patch would apply,
it will not work reliably.

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: 049e684f (media: v4l2-dev: fix WARN_ON(!vdev->device_caps))
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 0a1c80c6

drivers/media/v4l2-core/v4l2-ioctl.c

+3 −1
Original line number Diff line number Diff line
@@ -2090,6 +2090,7 @@ static int v4l_prepare_buf(const struct v4l2_ioctl_ops *ops, 
static int v4l_g_parm(const struct v4l2_ioctl_ops *ops,

				struct file *file, void *fh, void *arg)

{

	struct video_device *vfd = video_devdata(file);

	struct v4l2_streamparm *p = arg;

	v4l2_std_id std;

	int ret = check_fmt(file, p->type);
@@ -2101,6 +2102,7 @@ static int v4l_g_parm(const struct v4l2_ioctl_ops *ops, 
	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&

	    p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)

		return -EINVAL;

	if (vfd->device_caps & V4L2_CAP_READWRITE)

		p->parm.capture.readbuffers = 2;

	ret = ops->vidioc_g_std(file, fh, &std);

	if (ret == 0)