On 03/06/2014 08:43 PM, Chen-Yu Tsai wrote: > 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. 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). -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
