Re: [PATCH v7] regulator: fixed: Convert to use GPIO descriptor only

[Jon Hunter]

On 12/10/18 10:43, Marcel Ziswiler wrote:
> On Thu, 2018-10-11 at 19:47 +0200, Linus Walleij wrote:
>> On Thu, Oct 11, 2018 at 5:34 PM Marcel Ziswiler
>> <marcel.ziswiler@xxxxxxxxxxx> wrote:
>>
>>> I guess that is also what broke HDMI on Apalis/Colibri T30 causing
>>> me
>>> to submit a fix [1]. I may also help testing.
>>
>> I see there are many ways to skin this cat.
> 
> Yes, as a matter of fact I screened the kernel concerning this multi
> gpio stuff but could not quite find many examples and no mentioning
> anywhere whether or not this is actually allowed. So I kind of assumed
> that this may just not really be allowed and cooked up my patch which
> is anyway kind of a cleaner solution. I mean explicitly modelling the
> GPIO into some intermediate regulator supplying the others.

See the function 'regulator_ena_gpio_request()', it states that the same
GPIO pin can be shared among regulators.

We had the same situation for Tegra124 Jetson TK1 but I don't think that
adding a pseudo intermediate regulator is cleaner. If the GPIO controls
more than one regulator, I don't see why is it necessary to change the
DT. There are several other people reporting the same problem with
various different boards. So this does seem to be a common usage.

Cheers
Jon

-- 
nvpublic