[PATCH 3/4] arm: sunxi: Add AXP20X_ADC

[Chen-Yu Tsai]

On Mon, Jul 24, 2017 at 4:18 PM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> Hi,
>
> On Sat, Jul 22, 2017 at 10:19:08AM +0800, Chen-Yu Tsai wrote:
>> On Sat, Jul 22, 2017 at 12:20 AM, Maxime Ripard
>> <maxime.ripard at free-electrons.com> wrote:
>> > The APX20X_POWER option, that is a dependency of the USB controllers
>> > depends on IIO and AXP20X_ADC. Add it so that we can get a working USB
>> > back.
>>
>> The statement is only half true. AXP20X_POWER can fall back to reading
>> the ADC registers directly if AXP20X_ADC is not enabled. Is there a plan
>> to remove this feature?
>
> I never really considered this a feature, but some compatibility for
> older DTs to be honest :)
>
>> Also, AXP20X_ADC is only really needed if the hardware is AXP20x, and
>> not the later ones that don't have voltage/current sensing. I would
>> like to change the hard dependency on AXP20X_ADC to the "imply"
>> keyword in Kconfig for the AC and battery power supply drivers.
>
> I'm not sure. It's also needed when you want to read the battery
> voltage and current, or the AC-IN voltage. And that's a feature found
> on all PMICs.
>
> And since the battery and the AC-IN power supplies also have a
> dependency on AXP20X_ADC, I guess we can just add a depnds on. In most
> configuration, it's going to be enabled anyway.
>
>> That is another discussion though.
>
> Indeed.
>
>> So I think the description should be something like
>>
>>     AXP20X_POWER depends on IIO. Even though it does not depend on
>>     AXP20X_ADC, it is the new, preferred way of getting power supply
>>     readings. The other AXP power supply drivers use it as well.
>>
>>     Enable both options.
>
> That works for me.
>
> With that comment, do I have your Acked-By?

Yes. We'll figure out the rest later on.

Thanks
ChenYu