Re: [PATCH 3/5] drm/bridge: Add PTN3460 bridge driver

[Inki Dae]

2013/10/4 Olof Johansson <olof@xxxxxxxxx>:
> On Thu, Oct 3, 2013 at 10:39 AM, Inki Dae <inki.dae@xxxxxxxxxxx> wrote:
>> 2013/10/3 Sean Paul <seanpaul@xxxxxxxxxxxx>:
>>> On Thu, Oct 3, 2013 at 9:55 AM, Inki Dae <inki.dae@xxxxxxxxxxx> wrote:
>>>> Can a regulator be used instead of gpio in other board case?
>>>>
>>>
>>> No, not to my knowledge.
>>>
>>
>> Hm.. plz check it out again. the gpio pin is specific to board, and
>> the the gpio be used as power source trigger could be replaced with a
>> regulator according to board design. So you should consider all
>> possibilities even though there are no other cases yet: other board
>> could  use a regulator instead.
>
> Take a look at the data sheet, it is publicly available.
>
> PD_N is not a power supply input, so modelling it as a regulator makes no sense:
>
> "If PD_N is LOW, then the device is in Deep power-down completely,
> even if supply rail is ON; for the device to be able to operate, the
> PD_N pin must be HIGH."
>

I still think the pin could be replaced with a regulator. But
lvds-bridge node has "powerdown-gpio" property - it say this board
will use gpio pin - specific to board.  So it seems no problem.

>
>
> -Olof
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