On Sat, 2009-02-21 at 17:40 +0100, Hans Verkuil wrote:
> On Saturday 21 February 2009 16:48:00 Andy Walls wrote:
> > Hans,
> >
> > I think ivtv's new handling of S_STD for a GPIO mux has a bug. If the
> > user has a GPIO mux set to Composite 1/Audio Line-in 1, then a
> > VIDIOC_S_STD call will reroute the GPIO audio mux back to the tuner.
>
> Hmm, yes this is a very, very old bug. It was there from the very beginning.
> The idea is that when you are in radio mode, then a call to S_STD should
> switch you back to video mode.
Yeah. I got that.
I noted the V4L2 spec said switching inpuits could have side effect, but
not seting the standard once one had switched the input. The radio mode
abuse of S_STD has a disallowed side effect. :(
Quite a Catch 22 if you have a card with a PAL tuner, with GPIO mux
control, and want to switch the standard to NTSC on line in 1. (My
exact situation with the Conexant PAL/SECAM card.)
I just wanted to make sure this wasn't anything new.
> So there should be some additional
> administration here to keep track of the video input and set it back to
> that, rather than just choosing the tuner input.
>
> Of course, abusing S_STD for something like this is dubious as well, but it
> is rather low on the long list of things we can improve.
>
> To be honest, I don't feel terribly compelled to go in and fix it. I'm a bit
> too busy lately :-)
Not surprisingly, I've added a FIXME to the cx18 driver code and I am
moving on as well. :)
There is only one well supported card under cx18 that has a GPIO mux
control and it's not widely available.
Regards,
Andy
> Regards,
>
> Hans
_______________________________________________
ivtv-devel mailing list
ivtv-devel@ivtvdriver.org
http://ivtvdriver.org/mailman/listinfo/ivtv-devel