[alsa-devel] [PATCH v2 0/1] *** SUBJECT HERE ***

Mark Brown broonie at opensource.wolfsonmicro.com
Thu Jul 22 13:02:10 CEST 2010

On Thu, Jul 22, 2010 at 01:57:16PM +0300, Peter Ujfalusi wrote:

> I think the whole SNDRV_PCM_INFO_HALF_DUPLEX bit cleaning/setting can be left 
> out as such.

That would be even simpler, of course!

> My point is, that in wl1273_startup, the driver anyway will refuse the non 
> correct stream for FM mode. It is checking, that only playback can be started, 
> when the FM is in TX mode, and allows only capture, if the chip has been 
> configured to FM RX mode. In BT mode the codec can work in full duplex.

...and hopefully userspace won't be trying to do any of the unsupported
things anyway at a higher level than ALSA so that's probably OK.  I
guess in principle the device can support full duplex even with FM, it's
just that the output is going to get discarded so it's not *useful* so
there's not such a need to make sure userspace is told about the
restriction anyway - the CPU driver can do the DMA which is all that's
directly visible to the application.

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