[GIT PULL] STM32 DT fixes for v5.10 #1

[Marek Vasut]

On 10/28/20 6:38 PM, Ahmad Fatoum wrote:
> Hello Alex,

Hi,

> On 10/28/20 4:28 PM, Alexandre Torgue wrote:
>> Hi Arnd, Olof and Kevin,
>>
>> On v5.10-rc1 STM32 boards cannot boot. It is linked to a change in regulator framework which highlights that our supplies are not well described. This PR fixes it for STM32 boards that I have on my desk: ED1 and DKx.
> 
> Which change triggered the regression?

I think it might be:
aea6cb99703e ("regulator: resolve supply after creating regulator")
which landed in 5.4.73 as
0120ec32a777 ("regulator: resolve supply after creating regulator")

>> I assume that same patch has to be done for other STM32 boards, but as I don't have schematics I can't provide it. So a round2 has to be done for:
>> - stinger96
>> - MC-1
>> - Odyssey SOM
>> - DHCOR /DHCOM
>>
>> Mani, Marek, Ahmad, Marcin can you please have a look on it and provide patches (then I'll provide round2). Thanks in advance.
> 
> Your change doesn't look right. If I set vref_ddr-supply to a fixed regulator,
> the MC-1 now boots again as well, but that seems to just mask the real issue:
> 
>   - vref_ddr is an _output_ of the PMIC, why should one have to specify a supply for it?
> 
>   - This is actually incompatible with the binding. vref_ddr-supply isn't specified
>     as an allowed property (not to mention a required one)
> 
>   - Isn't the kernel supposed to stay compatible to old device trees?
> 
> I think the stpmic driver is at fault here and that the regulator framework change just
> made that apparent.

I agree updating the DT is not the right approach.