[alsa-devel] [RFC][ASoC] New device/driver arch

Nobin Mathew nobin.mathew at gmail.com
Fri Jun 15 14:06:54 CEST 2007

So in this architecture we will have so many devices registered to the kernel?

On 6/15/07, Liam Girdwood <lg at opensource.wolfsonmicro.com> wrote:
> On Thu, 2007-06-14 at 20:06 +0200, Manuel Lauss wrote:
> > Hi Liam,
> >
> > Is it possible to have 2 physical I2S units (which are connected to the same
> > codec) be repesented as a single ASoC device? (The SH7760 has 2 I2S units
> > which are "halfduplex" (only transmit OR capture at a time). My dev platform
> > simply uses the second unit for capture
> >
> Yes. I would create two struct snd_soc_device_drivers in your i2s.c
> file. The first would be the driver for the 2 halfduplex I2S units and
> the second would be a full duplex driver for a merged I2S controller
> (made up of the 2 halfduplex units). This way a device can either probe
> against the halfduplex or full duplex driver based on the driver ID.
> >
> > I need a trigger callback in the  machine driver to properly support
> > multichannel I2S audio on Au1200 (the  Au1200 can only do stereo; to get
> > more channels we double/quadruple the I2S LRCLK coming from the codec;
> > however the CPLD needs to be told when a new sample starts; although
> > maybe that can be worked around in VHDL)
> >
> I'll add trigger. Probably easier to do this in C than VHDL ;)
> Liam

More information about the Alsa-devel mailing list