Re: [PATCH 3/8] mfd: axp20x: probe axp20x_adc driver for AXP813

[Chen-Yu Tsai]

On Thu, Dec 7, 2017 at 5:03 PM, Quentin Schulz
<quentin.schulz@xxxxxxxxxxxxxxxxxx> wrote:
> Hi Chen-Yu,
>
> On 07/12/2017 09:54, Chen-Yu Tsai wrote:
>> On Thu, Dec 7, 2017 at 4:51 PM, Quentin Schulz
>> <quentin.schulz@xxxxxxxxxxxxxxxxxx> wrote:
>>> Hi Maxime,
>>>
>>> On 05/12/2017 09:08, Maxime Ripard wrote:
>>>> On Mon, Dec 04, 2017 at 03:12:49PM +0100, Quentin Schulz wrote:
>>>>> This makes the axp20x_adc driver probe with platform device id
>>>>> "axp813-adc".
>>>>>
>>>>> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
>>>>> ---
>>>>>  drivers/mfd/axp20x.c | 4 +++-
>>>>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
>>>>> index 2468b43..42e54d1 100644
>>>>> --- a/drivers/mfd/axp20x.c
>>>>> +++ b/drivers/mfd/axp20x.c
>>>>> @@ -878,7 +878,9 @@ static struct mfd_cell axp813_cells[] = {
>>>>>              .resources              = axp803_pek_resources,
>>>>>      }, {
>>>>>              .name                   = "axp20x-regulator",
>>>>> -    }
>>>>> +    }, {
>>>>> +            .name                   = "axp813-adc",
>>>>> +    },
>>>>
>>>> Any particular reason you're not adding it to the DT?
>>>>
>>>
>>> No, no particular reason. It's just the way it is currently for AXP209
>>> and AXP22x so did the same for AXP813.
>>>
>>> I'll add DT "support" in next version for all AXPs supported by this
>>> driver. Or is it worthy of a small separate patch series?
>>
>> IIRC there's no DT support because there's no need to reference
>> it in the device tree.
>>
>
> No current need but that does not mean there won't be a need later for
> drivers to map IIO channels from the ADC driver (i.e. some components
> wired to GPIOs of the PMIC for example).

Hmm... Why would you map the IIO channels from the ADC? I thought those
were all accessible from userspace?

However, proper muxing of the GPIO pin to the ADC function makes sense.

ChenYu