Re: [PATCH 2/3] ASoC: fsl_asrc: update supported sample format

On Tue, Sep 10, 2019 at 02:07:25AM +0000, S.j. Wang wrote:

quoted

On Mon, Sep 09, 2019 at 06:33:20PM -0400, Shengjiu Wang wrote:

quoted

The ASRC support 24bit/16bit/8bit input width, so S20_3LE format
should not be supported, it is word width is 20bit.

I thought 3LE used 24-bit physical width. And the driver assigns
ASRC_WIDTH_24_BIT to "width" for all non-16bit cases, so 20-bit would go
for that 24-bit slot also. I don't clearly recall if I had explicitly tested
S20_3LE, but I feel it should work since I put there...

For S20_3LE, the width is 20bit,  but the ASRC only support 24bit, if set the
ASRMCR1n.IWD= 24bit, because the actual width is 20 bit, the volume is
Lower than expected,  it likes 24bit data right shift 4 bit.
So it is not supported.

Hmm..S20_3LE right-aligns 20 bits in a 24-bit slot? I thought
they're left aligned...

If this is the case...shouldn't we have the same lower-volume
problem for all hardwares that support S20_3LE now?