Re: [PATCH] Make EN2 pin optional in the TRF7970A driver

[Rob Herring]

On Sun, Feb 19, 2017 at 11:19 PM, Heiko Schocher <hs@xxxxxxx> wrote:
> Hello all,
>
> Am 13.02.2017 um 22:31 schrieb Rob Herring:
>>
>> On Mon, Feb 13, 2017 at 12:38 AM, Heiko Schocher <hs@xxxxxxx> wrote:
>>>
>>> Hello Rob,
>>>
>>>
>>> Am 10.02.2017 um 16:51 schrieb Rob Herring:
>>>>
>>>>
>>>> On Tue, Feb 07, 2017 at 06:22:04AM +0100, Heiko Schocher wrote:
>>>>>
>>>>>
>>>>> From: Guan Ben <ben.guan@xxxxxxxxxxxx>
>>>>>
>>>>> Make the EN2 pin optional. This is useful for boards,
>>>>> which have this pin fix wired, for example to ground.
>>>>>
>>>>> Signed-off-by: Guan Ben <ben.guan@xxxxxxxxxxxx>
>>>>> Signed-off-by: Mark Jonas <mark.jonas@xxxxxxxxxxxx>
>>>>> Signed-off-by: Heiko Schocher <hs@xxxxxxx>
>>>>>
>>>>> ---
>>>>>
>>>>>    .../devicetree/bindings/net/nfc/trf7970a.txt       |  4 ++--
>>>>>    drivers/nfc/trf7970a.c                             | 26
>>>>> ++++++++++++----------
>>>>>    2 files changed, 16 insertions(+), 14 deletions(-)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>>>>> b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>>>>> index 32b35a0..5889a3d 100644
>>>>> --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>>>>> +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>>>>> @@ -5,8 +5,8 @@ Required properties:
>>>>>    - spi-max-frequency: Maximum SPI frequency (<= 2000000).
>>>>>    - interrupt-parent: phandle of parent interrupt handler.
>>>>>    - interrupts: A single interrupt specifier.
>>>>> -- ti,enable-gpios: Two GPIO entries used for 'EN' and 'EN2' pins on
>>>>> the
>>>>> -  TRF7970A.
>>>>> +- ti,enable-gpios: One or two GPIO entries used for 'EN' and 'EN2'
>>>>> pins
>>>>> on the
>>>>> +  TRF7970A. EN2 is optional.
>>>>
>>>>
>>>>
>>>> Could EN ever be optional/fixed? If so, perhaps deprecate this property
>>>> and do 2 properties, one for each pin.
>>>
>>>
>>>
>>> The hardware I have has the EN2 pin fix connected to ground. Looking
>>> into http://www.ti.com/lit/ds/slos743k/slos743k.pdf page 19 table 6-3
>>> and 6-4 the EN2 pin is a don;t core if EN = 1. If EN = 0 EN2 pin
>>> selects between Power Down and Sleep Mode ... I see no reason why
>>> this is not possible/allowed ...
>>>
>>> Hmm.. I do not like the idea of deprecating the "ti,enable-gpios"
>>> property into 2 seperate properties ... but if this would be a reason
>>> for not accepting this patch, I can do this ... How should I name
>>> the 2 new properties?
>>
>>
>> I guess if this ever happens, then we just add "ti,enable2-gpios" and
>> ti,enable-gpios continues to point to EN. We don't need to deprecate
>> anything (or maybe just deprecate having both GPIOs on single
>> property).
>>
>> In that case,
>>
>> Acked-by: Rob Herring <robh@xxxxxxxxxx>
>
>
> gentle ping.
>
> Are there any more comments to this patch? Is it acceptable as it
> is?

I acked it, so yes, it is fine.

Rob