On Thu, Apr 24, 2014 at 11:06 PM, Rob Herring <robherring2@xxxxxxxxx> wrote: > On Thu, Apr 24, 2014 at 7:47 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: >> On Wed, Apr 23, 2014 at 5:28 PM, Thierry Reding >> <thierry.reding@xxxxxxxxx> wrote: >> >>> From: Thierry Reding <treding@xxxxxxxxxx> >>> >>> Many bindings use the -gpio suffix in property names. Support this in >>> addition to the -gpios suffix when requesting GPIOs using the new >>> descriptor-based API. >>> >>> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> >> >> Are the DT bindings really full of such ambiguity between >> singular and plural? Examples? >> >> What happens in affected drivers today? It just doesn't work? > > They mostly seem to use of_get_named_gpio. In an idea world of_get_named_gpio() would be gpiolib-private so people cannot come with their own custom-named DT GPIO properties. Given its broad usage this is not possible, but maybe we can at least do it for of_get_named_gpiod(). > >> >> Does that mean these bindings are not actively used by any >> drivers yet so we could augment the bindings instead, or are >> they already deployed so we must implement this? >> >> Would like a word from the DT people here... > > Interestingly, there is not a single occurrence of '-gpio ' in > powerpc, but a bunch in ARM. In hindsight, we should have perhaps > enforced using -gpios only, but that doesn't really matter now. We > have -gpio in use, so we need to support it. That doesn't necessarily > mean this function has to support it. For example, this function could > a legacy method and some other function should be used instead > (of_get_named_gpio perhaps). It seems like we have to support that use-case indeed (many instances in arch/arm). The incentive for handling this in that function vs. user code is that having support here would allow drivers to directly use gpiod_get() and having it automatically handle GPIO properties like active-low instead of requiring user code to handle it by itself every time. Without this many drivers for devices using "-gpio" properties could not switch to the new gpiod interface. So as far as I'm concerned this code makes GPIO user-code easier. This is not to say that we should allow that "-gpio" suffix for new bindings. Acked-by: Alexandre Courbot <acourbot@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
