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    SubjectRe: [PATCHv2 3/5] net: rfkill: gpio: remove gpio names
    On 03/06/2014 08:43 PM, Chen-Yu Tsai wrote:
    > On Fri, Mar 7, 2014 at 11:41 AM, Linus Walleij <linus.walleij@linaro.org> wrote:
    >> On Wed, Mar 5, 2014 at 10:59 AM, Stephen Warren <swarren@wwwdotorg.org> wrote:
    >>> On 03/04/2014 07:37 PM, Linus Walleij wrote:
    >>>> On Wed, Mar 5, 2014 at 10:18 AM, Stephen Warren <swarren@wwwdotorg.org> 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.

    For any bindings that are already defined to use index-based lookups, I
    think we have to continue using them, for backwards-compatibility with
    old DTs (and I assume old ACPI databases need the same thing).



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