[alsa-devel] [PATCH V1 08/11] ASoc: DaVinci: i2s, Improve underrun, support mono

[Steve Chen]

On Mon, 2009-07-06 at 12:54 +0100, Mark Brown wrote:
> On Mon, Jul 06, 2009 at 06:09:16AM -0500, Steve Chen wrote:
> > On Sat, 2009-07-04 at 19:29 -0700, Troy Kisky wrote:
> 
> > > This patch will reduce the number of underruns by
> > > shifting out 32 bit values instead of 16 bit. It also
> > > adds mono support.
> 
> > Doesn't ALSA already automatically handle mono-stero conversions?  I
> > don't think we need to provide the same functionality in the driver.
> 
> If the hardware can natively play mono then that's less work for the CPU
> to do which will improve efficiency.

I see.  In this case, DaVinci hardware does not support mono, but the
patch does some DMA index magic to convert between mono and stereo.  It
works just as well then...