Re: [PATCH 1/3] ASoC: ti: omap-mcbsp: Ignore errors for getting fck_src

[Andreas Kemnade <andreas@kemnade.info>]

Hi,

On Wed, 20 Sep 2023 09:33:53 +0300
Tony Lindgren <tony@atomide.com> wrote:

> Hi,
> 
> * Péter Ujfalusi <peter.ujfalusi@gmail.com> [230919 18:25]:
> > 
> > 
> > On 7/5/23 22:03, Andreas Kemnade wrote:  
> > > Commit 349355ce3a05 ("ARM: OMAP2+: Drop legacy platform data for omap4 mcbsp")
> > > dropped prcm_fck for omap4,  
> 
> The prcm_fck should be there in the dts for each mcbsp interconnect targe
> module as "fck" alias and get's enabled/disabled when the mcbsp driver
> calls runtime PM.
> 
> So maybe the description should explain that things broke as the aliases
> for prcm_fck and pad_ck no longer get added.
> 
> > it also dropped the pad_fck for that matter.  
> 
> OK so an alias is needed for that too.
> 
> That's the MCPDM_CLKCTRL pad_clks_ck alias, right? Seems like the
> pad_clks_ck should be claimed by the mcpdm and mcbsp drivers if they are
> used? I guess it would be for some external device use case?
> 
> > > so the clk_src might not be >available making the
> > > clk_get(src) fail.  
> > 
> > Wow, so OMAP4 audio is pretty broken if would ever need to select FCLK?
> > By default we don't on OMAP4, but this is astonishing.  
> 
> So sounds like we just got lucky because of -ENOSUCHUSERS? The mcbsp works
> for me, not sure how come I'm not seeing this issue, does it now only work
> for the default clock source?
> 
Well, I did not run into any problems (besides of no sound output)
as long as I tried to use the codec side as bitclock/frameclock-master and
that is what droid4 does...

Regards,
Andreas