[PATCH 2/2] ASoC: sgtl5000: clean up sgtl5000_enable_regulators()

[Li.Xiubo at freescale.com]

> > Well, the regulator_get_optional() is still needed to improve.
> > For instance, if dts is not used for one platform and the external
> > VDDD supply is absent. The regulator_get_optional() will return
> > -EPROBE_DEFER, so the SGTL5000's probe, and then the SGTL5000 will do
> > the deferral probe, and this time the same -EPROBE_DEFER error will
> return again.
> 
> Yea, it seems in non-DT that regulator core can not figure out the -ENODEV
> case like it does in DT, so it simply returns -EPROBE_DEFER no matter
> whether the regulator is absent or it's present but just not registered yet.
> IOW, it can not distinguish between these two cases in non-DT case.
> 
> Neither am I aware of any non-DT SGTL5000 users in the tree, nor I care.
> I'm not concerned by this issue.
> 
> > Where should this special handling be dealt with ? Is here or
> > regulator_get_optional() will be better ?
> 
> Anyway, this is another issue which should be addressed in regulator core,
> IMO.
> 

Yes, agree.