[alsa-devel] Backported sbxfi driver (UNTESTED!)

[Takashi Iwai]

At Fri, 17 Oct 2008 14:01:55 +0400,
The Source wrote:
> 
> Takashi Iwai пишет:
> > At Fri, 17 Oct 2008 13:58:20 +0400,
> > The Source wrote:
> >   
> >> Takashi Iwai пишет:
> >>     
> >>> At Fri, 17 Oct 2008 11:57:08 +0400,
> >>> The Source wrote:
> >>>   
> >>>       
> >>>> Takashi Iwai пишет:
> >>>>     
> >>>>         
> >>>>> At Thu, 16 Oct 2008 22:18:07 +0400,
> >>>>> The Source wrote:
> >>>>>   
> >>>>>       
> >>>>>           
> >>>>>>>> Ok. OpenAL with alsa also seem to cause problems.
> >>>>>>>>     
> >>>>>>>>         
> >>>>>>>>             
> >>>>>>>>                 
> >>>>>>> In both cases, check the period_size and buffer_size values (shown in
> >>>>>>> the kernel message, or /proc/asound/card0/pcm0p/sub0/hw_params).
> >>>>>>> And, try to aplay with these parameters, whether you get the similar
> >>>>>>> problem.
> >>>>>>>
> >>>>>>> 	% aplay -v --period-size=xxx --buffer-size=yyy foo.wav
> >>>>>>>
> >>>>>>>
> >>>>>>> Takashi
> >>>>>>>
> >>>>>>>   
> >>>>>>>       
> >>>>>>>           
> >>>>>>>               
> >>>>>> I'm sorry, but any attemp to play file with ossplay results in complete 
> >>>>>> system hang with error:
> >>>>>> unable to handle NULL ponter dereference at address 
> >>>>>> 0000000000000008.....(hang, no more output).
> >>>>>> I tried many wav formats. So I can't get error log or period and buffer 
> >>>>>> sizes, sorry.
> >>>>>>     
> >>>>>>         
> >>>>>>             
> >>>>> Can anyone confirm to reproduce Oops with OSS apps (ossplay)?
> >>>>>
> >>>>> I'm wondering whether this has anything to do with the capture.
> >>>>> Can you record the sound, and change the capture mixer element properly?
> >>>>>
> >>>>>
> >>>>> thanks,
> >>>>>
> >>>>> Takashi
> >>>>>
> >>>>>   
> >>>>>       
> >>>>>           
> >>>> I checked mplayer. It uses period size 1024 instead of 4096 and 16384 
> >>>> buffer size (default). Sound is choppy (sound pauses is more frequent 
> >>>> when rate is lower).
> >>>> However an attempt to play the same file with the same period and buffer 
> >>>> sizes with aplay results in complete system hang.
> >>>>     
> >>>>         
> >>> OK, that looks like a problem.  Looks like the timer resolution can be
> >>> short like that, or something racy in the timer handling.
> >>>
> >>> Can you check whether this happens with XXX_SYSTEM_TIMER, too?
> >>>
> >>> Or, does the patch below avoid the problem, at least?
> >>>
> >>>
> >>> thanks,
> >>>
> >>> Takashi
> >>>
> >>> diff --git a/sound/pci/sbxfi/sbxfi.c b/sound/pci/sbxfi/sbxfi.c
> >>> index 26a6cd3..5ceb228 100644
> >>> --- a/sound/pci/sbxfi/sbxfi.c
> >>> +++ b/sound/pci/sbxfi/sbxfi.c
> >>> @@ -277,6 +277,7 @@ static void sbxfi_rearm_timer(struct sbxfi *chip, int ticks)
> >>>  #else
> >>>  
> >>>  #define MAX_TICKS	((1 << 13) - 1)
> >>> +#define MIN_TICKS	1000		/* FIXME: really so? */
> >>>  
> >>>  static void sbxfi_init_timer(struct sbxfi *chip)
> >>>  {
> >>> @@ -287,6 +288,8 @@ static void sbxfi_set_timer(struct sbxfi *chip, int ticks)
> >>>  	LOG(2, "SET TIMER TICKS = %d\n", ticks);
> >>>  	if (ticks > MAX_TICKS)
> >>>  		ticks = MAX_TICKS;
> >>> +	else if (ticks < MIN_TICKS)
> >>> +		ticks = MIN_TICKS;
> >>>  	sbxfi_write(chip, TIMR, ticks | TIMR_IE | TIMR_IP);
> >>>  }
> >>>  static void sbxfi_stop_timer(struct sbxfi *chip)
> >>>
> >>>   
> >>>       
> >> After patch:
> >>
> >> Without system timer:
> >>
> >> aplay --period-size=1024 96000_16_Stereo.wav
> >> Plays fine
> >>
> >> aplay --period-size=1024 22050_16_Mono.wav
> >> BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
> >> Hang
> >>
> >> With system timer:
> >>
> >> aplay --period-size=1024 96000_16_Stereo.wav
> >> Superglitch. Each sample is played many times before advancing to next one.
> >>
> >> aplay --period-size=1024 22050_16_Mono.wav
> >> Instant reboot.
> >>     
> >
> > Just to be sure: you don't enable XXX_CONT_RATE, right?
> > It's known to be buggy, so disabled as default now.
> >
> >
> > Takashi
> >
> >   
> It is disabled for me too.

And the patch didn't help?


Takashi