Re: [RFC 3/5] regulator: core: Only apply constraints if available on list voltage

[Mark Brown]

On Tue, Jul 29, 2014 at 06:28:57PM +0200, Javier Martinez Canillas wrote:
> If a selector can't be used on a platform due to voltage constraints,
> regulator_list_voltage() returns 0. Doing this unconditionally made
> sense since constraints were set in machine_constraints_voltage() at
> regulator registration time.
> 
> But for load switches that don't define a voltage output, the parent
> supply voltage is used so the constraints should only be applied if
> they were defined for the child regulators.

No, think about what you're doing here and why we're filtering out
unsettable voltages - this causes problems for consumers on regulators
that don't have any ability to vary voltages since they will now be able
to list voltages that they can't select.  

I would also expect any regulator where the supplied devices are able to
vary the voltage to explicitly provide a constraint even if the
implementation is done in a parent regulator.  There may be constraints
on the child supply which aren't directly present on the parent supply
and can be ignored if the child supply is turned off.

Attachment: signature.asc
Description: Digital signature