Re: [PATCHv2 3/5] net: rfkill: gpio: remove gpio names

From: Chen-Yu Tsai
Date: Thu Mar 06 2014 - 22:44:24 EST


On Fri, Mar 7, 2014 at 11:41 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
> On Wed, Mar 5, 2014 at 10:59 AM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote:
>> On 03/04/2014 07:37 PM, Linus Walleij wrote:
>>> On Wed, Mar 5, 2014 at 10:18 AM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote:
>>>> On 03/04/2014 06:43 PM, Linus Walleij wrote:
>>>
>>>>> If I understand the situation correctly it's like ACPI does not have named
>>>>> GPIOs so keeping specifying this in DT GPIO bindings is counter-productive
>>>>> to the work of abstracting the access to GPIO handlers so that drivers
>>>>> need not know whether ACPI or DT is used for describing the hardware.
>>>>
>>>> For devices that already have both ACPI and DT bindings, we can't
>>>> pretend they can be the same; they are already potentially different. We
>>>> simply need to parse DT and ACPI differently, since that's the sway
>>>> their bindings are defined.
>>>>
>>>> For any devices that don't have both ACPI and DT bindings, I agree we
>>>> should certainly strive to make any new bindings aligned so we don't
>>>> have to deal with this for them.
>>>>
>>>> However, we can't change the past.
>>>
>>> Yeah, right, so for this very driver there are no bindings defined (yet)
>>> and the only device tree I can find referencing it is the Tegra20-paz00
>>> and it just use gpios = <>;
>>>
>>> So in this case I think this patch is the right way forward, but I admit
>>> I'm really uncertain in the general case.
>>
>> If there are no bindings defined at all yet, then we can define both DT
>> and ACPI bindings to use name-based GPIOs. Index-based lookups aren't a
>> good way forward.
>
> After Mark clarifying that ACPI is going to have named GPIOs I'm
> totally aligned on this, so OK!

Glad to hear this, but is it possible to get rid of the index in current
drivers? Or change the behavior to name-based OR index-based lookups.
This might break any DTs that have multiple GPIOs defined under one
property though.


Cheers
ChenYu
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