[alsa-devel] ASoC: pxa2xx-ssp

[Daniel Ribeiro]

Em Qui, 2008-10-30 às 12:06 +0000, Mark Brown escreveu:
> On Thu, Oct 30, 2008 at 09:40:17AM -0200, Daniel Ribeiro wrote:
> 
> > 	Here are my test results for stereo S16_LE audio:
> 
> > 	set_tdm_slot(cpu_dai, 1, 2), SSCR0_Datasize(16):
> > 	Only left channel works.

+ Silent output on right channel.

> 
> > 	set_tdm_slot(cpu_dai, 2, 2), SSCR0_Datasize(16):
> > 	No I/O.
> 
> Could you expand on what you mean by "No I/O" here - do you get silent
> output or does DMA not work either?

DMA dont work.

> 
> > 	set_tdm_slot(cpu_dai, 3, 2), SSCR0_Datasize(16):
> > 	Only left channel works.

+ Silent output on right channel.

> 
> > 	set_tdm_slot(cpu_dai, 1, 1), SSCR0_Datasize(16) | SSCR0_EDSS:
> > 	Both channels work.
> 
> Just a thought, but you should also be able to get things working by
> adding a constraint on the format in your machine driver to force use of
> 32 bit - see things like the WM8903 driver for examples of how to this.
> Ideally that shouldn't be required, though.

I havent tried this yet, but if I set the codec driver to S32_LE
shouldnt it change the audio data format? According to the information I
have on this codec it only works with 16 bits audio format.

> 
> > 	On my board CLK and FRM are driven by the codec, pxa is slave. I have
> > no specs for the codec, only a 2.4 kernel driver that works with
> > (SSCR0_Datasize(16) | SSCR0_EDSS | SSCR0_SlotsPerFrm(1)).
> 
> Which codec is this?  Could you post the driver?

Its a motorola ASIC called PCAP2, it does a lot more than sound, and is
used on almost all Motorola phones (including WinCE and P2K phones) from
2004~2007.

http://git.openezx.org/?p=openezx.git;a=blob;f=sound/soc/codecs/pcap2.c;h=d5cf7d2e34a8565ed0e91094ee63f40236bb0b75;hb=18aeb9d03c0969b68fada1913b4d72ca8f47a912

> 
> BTW, your mail client is doing some really strange indentation here
> and indenting the first line of each paragraph by a tab which looks like
> how some other clients do quotation.

Sorry, im used to indent each paragraph with a tab, its not my mail
client, its me. :)

-- 
Daniel Ribeiro