__video_register_device: warning cannot be reached if warn_if_nr_in_use

__video_register_device: warning cannot be reached if warn_if_nr_in_use

[Richard Zhao]

In file drivers/media/video/v4l2-dev.c

int __video_register_device(struct video_device *vdev, int type, int nr,
		int warn_if_nr_in_use, struct module *owner)
{
[...]
	vdev->minor = i + minor_offset;
878:	vdev->num = nr;

vdev->num is set to nr here. 
[...]
	if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
		printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
			name_base, nr, video_device_node_name(vdev));

so nr != vdev->num is always false. The warning can never be printed.

Thanks
Richard

Re: __video_register_device: warning cannot be reached if warn_if_nr_in_use

[Hans Verkuil]

On Thu August 9 2012 14:55:02 Richard Zhao wrote:
> In file drivers/media/video/v4l2-dev.c
> 
> int __video_register_device(struct video_device *vdev, int type, int nr,
> 		int warn_if_nr_in_use, struct module *owner)
> {
> [...]
> 	vdev->minor = i + minor_offset;
> 878:	vdev->num = nr;
> 
> vdev->num is set to nr here. 
> [...]
> 	if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
> 		printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
> 			name_base, nr, video_device_node_name(vdev));
> 
> so nr != vdev->num is always false. The warning can never be printed.

Hmm, true. The question is, should we just fix this, or drop the warning altogether?
Clearly nobody missed that warning.

I'm inclined to drop the warning altogether and so also the video_register_device_no_warn
inline function.

What do others think?

	Hans

Re: __video_register_device: warning cannot be reached if warn_if_nr_in_use

[Richard Zhao]

Hans Verkuil <hverkuil@xs4all.nl> wrote:

>On Thu August 9 2012 14:55:02 Richard Zhao wrote:
>> In file drivers/media/video/v4l2-dev.c
>> 
>> int __video_register_device(struct video_device *vdev, int type, int
>nr,
>> 		int warn_if_nr_in_use, struct module *owner)
>> {
>> [...]
>> 	vdev->minor = i + minor_offset;
>> 878:	vdev->num = nr;
>> 
>> vdev->num is set to nr here. 
>> [...]
>> 	if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
>> 		printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
>> 			name_base, nr, video_device_node_name(vdev));
>> 
>> so nr != vdev->num is always false. The warning can never be printed.
>
>Hmm, true. The question is, should we just fix this, or drop the
>warning altogether?
>Clearly nobody missed that warning.
>
>I'm inclined to drop the warning altogether and so also the
>video_register_device_no_warn
>inline function.
>
>What do others think?
+1

Richard
>
>	Hans
>--
>To unsubscribe from this list: send the line "unsubscribe linux-media"
>in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
>From android phone

Re: __video_register_device: warning cannot be reached if warn_if_nr_in_use

[Sylwester Nawrocki]

On 08/09/2012 03:19 PM, Hans Verkuil wrote:
> On Thu August 9 2012 14:55:02 Richard Zhao wrote:
>> In file drivers/media/video/v4l2-dev.c
>>
>> int __video_register_device(struct video_device *vdev, int type, int nr,
>> 		int warn_if_nr_in_use, struct module *owner)
>> {
>> [...]
>> 	vdev->minor = i + minor_offset;
>> 878:	vdev->num = nr;
>>
>> vdev->num is set to nr here. 
>> [...]
>> 	if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
>> 		printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
>> 			name_base, nr, video_device_node_name(vdev));
>>
>> so nr != vdev->num is always false. The warning can never be printed.
> 
> Hmm, true. The question is, should we just fix this, or drop the warning altogether?
> Clearly nobody missed that warning.
> 
> I'm inclined to drop the warning altogether and so also the video_register_device_no_warn
> inline function.
> 
> What do others think?

Yeah, let's remove it.

--

Regards,
Sylwester


-- 
Sylwester Nawrocki
실베스터 나브로츠키
Samsung Poland R&D Center