Re: [RFCv2 PATCH 32/34] v4l2-dev.c: also add debug support for the fops.

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Hans,

Thanks for the patch.

On Friday 22 June 2012 14:21:26 Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@cisco.com>
> 
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> ---
>  drivers/media/video/v4l2-dev.c |   25 ++++++++++++++++++++++++-
>  1 file changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
> index 1b34360..b51bee9 100644
> --- a/drivers/media/video/v4l2-dev.c
> +++ b/drivers/media/video/v4l2-dev.c
> @@ -305,6 +305,9 @@ static ssize_t v4l2_read(struct file *filp, char __user
> *buf, ret = vdev->fops->read(filp, buf, sz, off);
>  	if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags))
>  		mutex_unlock(vdev->lock);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: read: %zd (%d)\n",
> +			video_device_node_name(vdev), sz, ret);

Would it make sense to introduce a v4l_dbg macro ? BTW, what was the outcome 
of the pr_ vs. dev_ tests ?

>  	return ret;
>  }
> 
> @@ -323,6 +326,9 @@ static ssize_t v4l2_write(struct file *filp, const char
> __user *buf, ret = vdev->fops->write(filp, buf, sz, off);
>  	if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags))
>  		mutex_unlock(vdev->lock);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: write: %zd (%d)\n",
> +			video_device_node_name(vdev), sz, ret);
>  	return ret;
>  }
> 
> @@ -339,6 +345,9 @@ static unsigned int v4l2_poll(struct file *filp, struct
> poll_table_struct *poll) ret = vdev->fops->poll(filp, poll);
>  	if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags))
>  		mutex_unlock(vdev->lock);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: poll: %08x\n",
> +			video_device_node_name(vdev), ret);
>  	return ret;
>  }
> 
> @@ -403,12 +412,17 @@ static unsigned long v4l2_get_unmapped_area(struct
> file *filp, unsigned long flags)
>  {
>  	struct video_device *vdev = video_devdata(filp);
> +	int ret;
> 
>  	if (!vdev->fops->get_unmapped_area)
>  		return -ENOSYS;
>  	if (!video_is_registered(vdev))
>  		return -ENODEV;
> -	return vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
> +	ret = vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: get_unmapped_area (%d)\n",
> +			video_device_node_name(vdev), ret);
> +	return ret;
>  }
>  #endif
> 
> @@ -426,6 +440,9 @@ static int v4l2_mmap(struct file *filp, struct
> vm_area_struct *vm) ret = vdev->fops->mmap(filp, vm);
>  	if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags))
>  		mutex_unlock(vdev->lock);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: mmap (%d)\n",
> +			video_device_node_name(vdev), ret);
>  	return ret;
>  }
> 
> @@ -464,6 +481,9 @@ err:
>  	/* decrease the refcount in case of an error */
>  	if (ret)
>  		video_put(vdev);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: open (%d)\n",
> +			video_device_node_name(vdev), ret);
>  	return ret;
>  }
> 
> @@ -483,6 +503,9 @@ static int v4l2_release(struct inode *inode, struct file
> *filp) /* decrease the refcount unconditionally since the release()
>  	   return value is ignored. */
>  	video_put(vdev);
> +	if (vdev->debug)
> +		printk(KERN_DEBUG "%s: release\n",
> +			video_device_node_name(vdev));
>  	return ret;
>  }
-- 
Regards,

Laurent Pinchart