[alsa-devel] [PATCH 3/3] ASoC: tlv320aic3x: Complete the soc-cache conversion

Jarkko Nikula jhnikula at gmail.com
Tue Sep 14 14:45:25 CEST 2010

On Tue, 14 Sep 2010 13:21:39 +0100
Mark Brown <broonie at opensource.wolfsonmicro.com> wrote:

> On Tue, Sep 14, 2010 at 03:14:45PM +0300, Jarkko Nikula wrote:
> > Mark Brown <broonie at opensource.wolfsonmicro.com> wrote:
> > > It'd be a bit nicer to do this by using snd_soc_read() here also and
> > > marking the registers as volatile.  This makes the process much less
> > > error prone since users can just use snd_soc_read() and the register
> > > cache code will work out if it needs to go to the chip or not.
> > Actually I looked that but problem with aic3x is that most of the
> > volatile bits are with r/w configuration bits in the same registers.
> > There are a few completely volatile read-only registers but currently
> > there is no use for them.
> Oh, so you would essentially kill the cache?  Sad.  It'd be nice to put
> comments somewhere in the driver noting this to discourage people doing
> the change.

Well cache is then out of sync with regarding of those gpio & headset
detect bits here but there wasn't use for them elsewhere so at the
moment it looks like null-op to write value to cache.

But is it marking register as volatile due 1-2 bits causing more
problems if we don't cache rest of the r/w bits?


More information about the Alsa-devel mailing list