On 25/06/2025 09:35, Bartosz Golaszewski wrote: > On Tue, 24 Jun 2025 at 21:44, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: >> >> On Tue, Jun 24, 2025 at 3:19 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote: >> >>> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> >>> >>> Ahead of removing struct bgpio_pdata support from the gpio-mmio generic >>> module, let's add support for getting the relevant values from generic >>> device properties. "label" is a semi-standardized property in some GPIO >>> drivers so let's go with it. There's no standard "base" property, so >>> let's use the name "gpio-mmio,base" to tie it to this driver >>> specifically. The number of GPIOs will be retrieved using >>> gpiochip_get_ngpios() so there's no need to look it up in the software >>> node. >>> >>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> >> >> This works for me. >> I wouldn't be stoked to see device trees abusing the "gpio-mmio,base" >> property all of a sudden just because it now exists as a device >> property though... I kind of wish we had a way to opt out of exposing >> this to all the sub-property paths. But it seems tiresome, so: >> >> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> >> >> Yours, >> Linus Walleij > > That's not a problem - this property is not in any DT bindings and as > such is not an allowed property in DT sources. For out-of-tree DTs? We > don't care about those. That's not true, we do care about implied ABI. Try changing/breaking this later, when users complain their out of tree DTS is affected, and explaining this all to Greg. Rob was/is working on tools checking this for such implied ABI, I think. For of_xxx() calls it is obvious, for device_xxx() or fwnode_xxx() it is not, therefore please add a comment that this is not allowed to be used by Devicetree platforms (or that this is only for ACPI/platform_data/whatever). I don't have any other guideline/solution other than a comment. Best regards, Krzysztof
