wm8962 0-001a: ASoC: error at soc_component_read_no_lock on wm8962.0-001a: -16

[Adam Ford]

On Mon, Oct 3, 2022 at 5:41 AM Charles Keepax
<ckeepax at opensource.cirrus.com> wrote:
>
> On Fri, Sep 30, 2022 at 12:59:24PM +0800, Wang, Xiaolei wrote:
> > On 9/29/2022 5:24 PM, Charles Keepax wrote:
> > >On Wed, Sep 28, 2022 at 02:44:30AM +0000, Wang, Xiaolei wrote:
> > >>snd_soc_bind_card
> > >>      snd_soc_dapm_new_widgets
> > >>          soc_dapm_read
> > >>              snd_soc_component_read(dapm->component, reg);
> > >>
> > >>There is no runtime resume, which cannot perform normal
> > >>reading and writing for volatile reg, because it has been
> > >>switched to regcache only in the process of runtime suspend. I
> > >>can't find the right place to resume, can you give me any
> > >>advice?
> > >>
> > >I think the first step would be could you clarify which register
> > >is being read here? Reading a volatile register as part of
> > >setting up the widgets does feel rather problematic.
> >
> > Yes, this is reading the 0x30 register of the wm8962, it can adjust
> > Microphone Bias Voltage.
>
> Yes, that is some rather poor hardware design there, the chip has
> a bunch of volatile status bits mixed in with a bunch of
> non-volatile control bits in the same register. It would seem
> the problem is likely the two widgets TEMP_HP and TEMP_SPK.
>
> Probably the simplest solution would be to add an event handler
> for TEMP_HP and TEMP_SPK and move the register handling in there,
> if there is no register specified on the widgets the core will
> not attempt to read it on probe and will assume the widget is
> off. Although you will also need to turn them off during probe as
> they do default to on.
>
> Is that something you are comfortable writing a patch for or do
> you want me to have a look at pulling one together for you?
> Although note this might take a few days and I don't have hardware
> to test it here.

I can test it if someone wants to copy me on the patch.  I see the
same splat, but it doesn't appear to impact the performance in my
application.

adam
>
> Thanks,
> Charles