Re: [PATCH v2 2/7] ASoC: fsl_rpmsg: Add CPU DAI driver for audio base on rpmsg

[Shengjiu Wang]

On Wed, Feb 10, 2021 at 11:39 PM Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> On Wed, Feb 10, 2021 at 02:35:29PM +0800, Shengjiu Wang wrote:
> > On Wed, Feb 10, 2021 at 6:30 AM Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> > > Like I say I'd actually recommend moving this control to DAPM.
>
> > I may understand your point, you suggest to use the .set_bias_level
> > interface. But in my case I need to enable the clock in earlier stage
> > and keep the clock on when system go to suspend.
>
> The device can be kept alive over system suspend if that's needed, or
> possibly it sounds like runtime PM is a better fit?  There's callbacks
> in the core to keep the device runtime PM enabled while it's open which
> is probably about the time range you're looking for.

Before enabling the clock, I need to reparent the clock according to
the sample rate,  Maybe the hw_params is the right place to do
these things.

Can I add a flag:
"rpmsg->mclk_streams & BIT(substream->stream)"
for avoiding multiple calls of hw_params function before enabling
clock?