On Wed, Sep 4, 2013 at 9:56 PM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote: > On 09/04/2013 05:29 AM, Alexandre Courbot wrote: >> Add gpiod_get() and gpiod_put() functions that provide safer handling of >> GPIOs. >> >> These functions put the GPIO framework in line with the conventions of >> other frameworks in the kernel, and help ensure every GPIO is declared >> properly and valid while it is used. > >> diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h > >> +struct gpio_desc *__must_check gpiod_get(struct device *dev, >> + const char *con_id); >> +void gpiod_put(struct gpio_desc *desc); > > It might be nice to add an "int index" parameter to this function. For > example, a bit-banged parallel bus protocol driver might have 1 > chip-select GPIO, 1 clock GPIO, and 8 data GPIOs. gpiod_get(dev, "bus", > 0)..gpiod_get(dev, "bus", 7) might be nicer than gpiod_get(dev, > "bus0")..gpiod_get(dev, "bus7")? Possibly for client-simplicity, > implement both gpiod_get(dev, con_id) (as an inline wrapper for ...) and > gpiod_get_index(dev, con_id, index)? > > In DT terms, this would map to: > > cs-gpios = <&gpio 3 0>; > clock-gpios = <&gpio 5 0>; > bus-gpios = <&gpio 10 0 ... &gpio 17 0>; > > ... and with the mapping table registration mechanism, we could > presumably add "int index" to struct gpiod_lookup. This is an interesting usability aspect of the API, so I'd especially like some input from the ACPI people on this as well. Paging Mika, Rafael, Mathias. Yours, Linus Walleij -- 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
