SPI PCM capture device examples please

SPI PCM capture device examples please

[Matt Flax]

Hi there,

Is it possible to write an ALSA driver for a device which already has an 
SPI driver ?

I have been trying to look for examples in the ALSA kernel source tree, 
however all the drivers I have looked at use SPI to control the codecs 
.... there must be an example where the codec uses SPI for PCM data ?

If someone is aware of any codecs which use SPI for PCM data can you 
please link me to the example driver code ?

The device I am interested in operates in slave SPI mode and only has 
ADCs, so it only has one input SPI line (and other necessary lines, such 
as clk). Its data sample rates are up to 1 M Hz.

Here is a link to the SPI driver in question :
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/iio/adc/ad7476.c?id=HEAD

thanks
Matt

Re: SPI PCM capture device examples please

[Matt Flax]

I guess that IIO support for ASLA is not on the cards ?

Matt

On 13/11/13 23:07, Matt Flax wrote:
> Hi there,
>
> Is it possible to write an ALSA driver for a device which already has 
> an SPI driver ?
>
> I have been trying to look for examples in the ALSA kernel source 
> tree, however all the drivers I have looked at use SPI to control the 
> codecs .... there must be an example where the codec uses SPI for PCM 
> data ?
>
> If someone is aware of any codecs which use SPI for PCM data can you 
> please link me to the example driver code ?
>
> The device I am interested in operates in slave SPI mode and only has 
> ADCs, so it only has one input SPI line (and other necessary lines, 
> such as clk). Its data sample rates are up to 1 M Hz.
>
> Here is a link to the SPI driver in question :
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/iio/adc/ad7476.c?id=HEAD 
>
>
> thanks
> Matt
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel

Re: SPI PCM capture device examples please

[Clemens Ladisch]

Matt Flax wrote:
>> Is it possible to write an ALSA driver for a device which already has an SPI driver ?

Yes, this is possible.

Audio codecs typcially do not use SPI, so no such driver has been
written yet.

> I guess that IIO support for ASLA is not on the cards ?

Well, that depends on whether you are going to write that driver ...


Regards,
Clemens

Re: SPI PCM capture device examples please

[Lars-Peter Clausen]

On 11/14/2013 03:12 PM, Clemens Ladisch wrote:
> Matt Flax wrote:
>>> Is it possible to write an ALSA driver for a device which already has an SPI driver ?
> 
> Yes, this is possible.
> 
> Audio codecs typcially do not use SPI, so no such driver has been
> written yet.
> 
>> I guess that IIO support for ASLA is not on the cards ?
> 
> Well, that depends on whether you are going to write that driver ...

There is already a IIO driver for this part. So if you really wanted to use
it using the ALSA userspace API the best solution would be to write a
generic IIO-to-ALSA bridge.

- Lars