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New ctrl framework also enumerates classes

DISCUSSION Hans de Goede 2 participants 3 messages Jul 4, 2011 – Jul 11, 2011 Media (V4L/DVB)

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Hi All,

One last thing before I really leave on vacation which just popped in my mind as something which I had not mentioned yet.

The new ctrl framework also enumerates classes when enumerating ctrls with the next flag. I wonder if this is intentional?

IOW if this is a feature or a bug?

Either way this confuses various userspace apps, gtk-v4l prints warnings about an unknown control type, and v4l2ucp gets a very messed up UI because of this change. Thus unless there are really strong reasons to do this, I suggest we skip classes when enumerating controls.

Regards,

Hans

#1 lore raw
Quoted 7 lines · On Monday, July 04, 2011 08:23:10 Hans de Goede wrote:

Hi All,

One last thing before I really leave on vacation which just popped in my mind as something which I had not mentioned yet.

The new ctrl framework also enumerates classes when enumerating ctrls with the next flag. I wonder if this is intentional?

It's absolutely intentional. It's needed to produce the headers of the tabs in e.g. qv4l2. It's been part of the spec for several years now.

Quoted 4 lines

IOW if this is a feature or a bug?

Either way this confuses various userspace apps, gtk-v4l prints warnings about an unknown control type,

It should just skip such types.

Quoted 4 lines

and v4l2ucp gets a very
messed up UI because of this change. Thus unless there are really strong reasons to do this, I suggest we skip classes when enumerating controls.

Those apps should be fixed. If apps see an unknown type, then they should always just skip such controls (and later add support for it, of course).

Another control type (bitmask) will be merged soon as well, so the same problem will occur with that, but this is all really an application bug. Apps should be tested with vivi: that driver has all control types that we have, so that's a good driver to test with.

Regards,

Hans

#2 lore raw

Hi,

Quoted 19 lines · Hans Verkuil
Quoted 7 lines · On Monday, July 04, 2011 08:23:10 Hans de Goede wrote:

Hi All,

One last thing before I really leave on vacation which just popped in my mind as something which I had not mentioned yet.

The new ctrl framework also enumerates classes when enumerating ctrls with the next flag. I wonder if this is intentional?

It's absolutely intentional. It's needed to produce the headers of the tabs in e.g. qv4l2. It's been part of the spec for several years now.

Quoted 4 lines

IOW if this is a feature or a bug?

Either way this confuses various userspace apps, gtk-v4l prints warnings about an unknown control type,

It should just skip such types.

Quoted 7 lines
Quoted 4 lines

and v4l2ucp gets a very
messed up UI because of this change. Thus unless there are really strong reasons to do this, I suggest we skip classes when enumerating controls.

Those apps should be fixed. If apps see an unknown type, then they should always just skip such controls (and later add support for it, of course).

Ok, I will fix those apps (for gtk-v4l I'm involved upstream, for v4l2ucp I'll fix it for Fedora and submit a patch upstream).

Regards,

Hans