On Thu, 2016-06-30 at 20:55 +0800, Garlic Tseng wrote:

On Wed, 2016-06-29 at 20:15 +0100, Mark Brown wrote:

quoted

On Fri, Jun 17, 2016 at 03:43:58PM +0800, Garlic Tseng wrote:

quoted

Add supports for 16k (wideband BT) and add a general compatible
string "linux,bt-sco"

This will claim that we support 16k on existing systems which we clearly
don't.  It also seems unwise to advertise multiple rates when we've no
way to configure the rates...  how does the BT controller figure out
what the sample rate is?

The codec driver is a dummy driver for bt device and actually do
nothing. The user-space will control both bt part and alsa part (at
least in mt2701 platform). Yes the sound/soc/codecs/bt-sco.c was only
support 8k and was already there before the patch, but I think it might
be ok to extend it to 16k without any side effect.

If you worry about some potential risk (I don't see any) maybe we have
to develop another dummy bt-sco codec driver which support both 8k and
16k?

Ah! If someone whose bluetooth modules only support 8k use the driver,
they might be broken, right? Maybe we can add another snd_soc_dai_driver
which can support both 8k and 16k.
(Actually I found the issue is discussed before
http://mailman.alsa-project.org/pipermail/alsa-devel/2014-November/084687.html )