Hi Paul,
On 2020-03-31 15:09, Paul Cercueil wrote:
> Cc: Paweł Chmiel <pawel.mikolaj.chmiel@xxxxxxxxx>
>
> Hi Marek,
>
> Le mar. 31 mars 2020 à 7:36, Marek Szyprowski
> <m.szyprowski@xxxxxxxxxxx> a écrit :
>> Hi Paul,
>>
>> On 2020-03-18 15:25, Paul Cercueil wrote:
>>>>> + };
>>>>> +
>>>>> + tsp_reg: regulator-1 {
>>>>> + compatible = "regulator-fixed";
>>>>> + regulator-name = "TSP_FIXED_VOLTAGES";
>>>>> + regulator-min-microvolt = <3300000>;
>>>>> + regulator-max-microvolt = <3300000>;
>>>>> + gpio = <&gpl0 3 GPIO_ACTIVE_HIGH>;
>>>>> + startup-delay-us = <70000>;
>>>>> + enable-active-high;
>>>>> + regulator-boot-on;
>>>>> + regulator-always-on;
>>>>
>>>> always-on and boot-on should not be needed. You have a consumer
>>>> for this
>>>> regulator.
>>>
>>> About this: the touchscreen driver does not use a regulator, so I
>>> believe that's why these properties were here.
>>>
>>> I sent patches upstream to address the issue:
>>> https://protect2.fireeye.com/url?k=e8aedc29-b53072b3-e8af5766-0cc47a336fae-759579fd576d8382&u=https://lkml.org/lkml/2020/3/15/94
>>>
>>>
>>> I believe this means I cannot merge the i9100 devicetree until it is
>>> acked.
>>
>> One more information - similar change has been already posted, but it
>> looks it got lost then: https://patchwork.kernel.org/patch/10550903/
>
> I was aware of this patch, but didn't know it was sent upstream.
>
> This other patch uses two regulators, vdd/avdd but doesn't give any
> reason why.
>
I've checked the UniversalC210 schematic, which uses the same
touchscreen chip. There are 2 supplies to the touchscreen chip: 2.8V VDD
and 3.3V AVDD. Both are enabled by the same GPIO pin though. There is
however no reset GPIO pin there.
> Paweł, is that really needed?
>
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
