Hi Hans,
I'm sorry for the delay.
This series still sounds useful, so let's try to
revive it.
On Mon, 2019-03-11 at 12:16 +0100, Hans Verkuil wrote:
> On 2/27/19 6:07 PM, Ezequiel Garcia wrote:
> > In preparation to cleanup the debug logic, simplify the dev_debug
> > usage. In particular, make sure that a single flag is used to
> > control each debug print.
> >
> > Before this commit V4L2_DEV_DEBUG_STREAMING and V4L2_DEV_DEBUG_FOP
> > were needed to enable read and write debugging. After this commit
> > only the former is needed.
>
> The original idea was that ioctls are logged with V4L2_DEV_DEBUG_IOCTL
> and file ops with V4L2_DEV_DEBUG_FOP. And to see the streaming ioctls
> or fops you would have to add V4L2_DEV_DEBUG_STREAMING in addition to
> DEBUG_IOCTL/FOP.
>
> This patch changes the behavior in that the streaming fops are now
> solely controlled by V4L2_DEV_DEBUG_STREAMING.
>
> I do agree with this change, but this requires that the same change is
> done for the streaming ioctls (DQBUF/QBUF) and that the documentation in
> Documentation/media/kapi/v4l2-dev.rst is updated (section "video device
> debugging").
>
Oops, I managed to somehow miss (D)QBUF, even though it's perfectly
well documented in the header!
Will fix, and will fix the documentation as well.
> Of course, the documentation should also mention the new dev_debug
> module parameter and the new debug flag for debugging controls.
>
> Regards,
>
> Hans
>
> > Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> > ---
> > drivers/media/v4l2-core/v4l2-dev.c | 6 ++----
> > 1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> > index d7528f82a66a..34e4958663bf 100644
> > --- a/drivers/media/v4l2-core/v4l2-dev.c
> > +++ b/drivers/media/v4l2-core/v4l2-dev.c
> > @@ -315,8 +315,7 @@ static ssize_t v4l2_read(struct file *filp, char __user *buf,
> > return -EINVAL;
> > if (video_is_registered(vdev))
> > ret = vdev->fops->read(filp, buf, sz, off);
> > - if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
> > - (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
> > + if (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING)
> > dprintk("%s: read: %zd (%d)\n",
> > video_device_node_name(vdev), sz, ret);
> > return ret;
> > @@ -332,8 +331,7 @@ static ssize_t v4l2_write(struct file *filp, const char __user *buf,
> > return -EINVAL;
> > if (video_is_registered(vdev))
> > ret = vdev->fops->write(filp, buf, sz, off);
> > - if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
> > - (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
> > + if (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING)
> > dprintk("%s: write: %zd (%d)\n",
> > video_device_node_name(vdev), sz, ret);
> > return ret;
> >
