[alsa-devel] [PATCH 2/3] ASoC: cs4265: Add native 32bit I2S transport

[Charles Keepax]

On Wed, Aug 29, 2018 at 09:31:31AM +1000, Matt Flax wrote:
> 
> 
> On 29/08/18 04:56, Mark Brown wrote:
> >On Mon, Aug 27, 2018 at 09:28:43AM +0100, Charles Keepax wrote:
> >
> >>Are you sure this is correct? The datasheet for the part only
> >>says it supports up to 24-bit audio and I thought the defines
> >>SNDRV_PCM_FMTBIT_S24_LE and U24 are expected to have 32-bits
> >>in the slot whilst on the bus.
> >No, they're not.  They're expected to be 32 bit in memory and 24 bit on
> >the bus.
> >
> 
> If this is the case, then I would assume that 32bit formats are
> forced through ALSA plughw.
> 
> If operation is forced through plughw, then this patch is necessary
> to allow native 32 operation on the bus. The codec drops the 8 LSBs
> during operation as it reads/writes the 24 MSBs.
> 

Yeah apologies for the confusion I imagine this patch is then
fine.

Thanks,
Charles