[linux-dvb] Re: Slow tuning with nova-t since Dec 5th tda1004x

[Johannes Stezenbach <js@linuxtv.org>]

On Tue, Jan 04, 2005 at 11:24:33PM +1100, Hamish Moffatt wrote:
> On Tue, Jan 04, 2005 at 04:50:09AM +0000, Andrew de Quincey wrote:
> > Got it - its the second change thats doing it I think.
> > 
> > Johannes, what bug was revision 1.98 of dvb_frontend.c fixing? I can't 
> > actually see what the problem was. With the change, it is no longer waiting 
> > for the minimum time for the frontend to lock so it'll cause lots of 
> > unnecessary retunes...

I just read through the code and saw that the wake_up_interruptible() is
a no-op (you can't wake up a process which is not sleeping). I then
guessed that the "goto retune" was intended (worked fine with my cards).
So if this guess was wrong you might just remove the wake_up()
completely.

Johannes


> You are right. I made the following change and now tuning is fast again
> on the tda1004x.
> 
> Hamish
> 
> diff -urN linux-2.6.10/drivers/media/dvb/dvb-core/dvb_frontend.c linux-2.6.10-patched/drivers/media/dvb/dvb-core/dvb_frontend.c
> --- linux-2.6.10/drivers/media/dvb/dvb-core/dvb_frontend.c	2004-12-27 17:13:55.000000000 +1100
> +++ linux-2.6.10-patched/drivers/media/dvb/dvb-core/dvb_frontend.c	2005-01-04 18:56:57.000000000 +1100
> @@ -454,7 +454,8 @@
>  			 * occurs */
>  			if (fe->state & FESTATE_RETUNE) {
>  				fe->state = FESTATE_TUNING_FAST;
> -				goto retune;
> +				/*goto retune;*/
> +				wake_up_interruptible(&fe->wait_queue);
>  			}
>  		}
>