Messages in this thread | | | Date | Wed, 29 Jun 2011 09:39:46 +0200 | Subject | Re: [PATCH 0/2] RFC: gpio: driver-local pin configuration | From | Stijn Devriendt <> |
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On Wed, Jun 29, 2011 at 8:18 AM, Linus Walleij <linus.walleij@linaro.org> wrote: > 2011/6/28 Stijn Devriendt <highguy@gmail.com>: >> On Mon, Jun 27, 2011 at 2:37 PM, Linus Walleij <linus.walleij@linaro.org> wrote: >>> On Mon, Jun 27, 2011 at 2:02 PM, Mark Brown >>>> How about device tree usage? I guess there we'd end up doing it by >>>> putting the configuration on the GPIO end of things rather than on the >>>> GPIO user side? >>> >>> Sorry I can't quite understand that, please elaborate! >>> >> >> I have some code doing this as well (in a very limited fashion): >> >> int of_request_gpio(..., int* remaining_flags) >> { >> of_get_gpio_flags(of_dev, i, remaining_flags) >> if (flags & bias_X) { >> gpio_set_bias(gpio, ...) >> flags &= ~bias_X >> } >> // interpret all generic flags here >> }; >> >> So drivers need not worry about all gpio flags and special things. >> They just request the pin; what they receive is a fully configured >> pin (with the exception of unknown flags passed out via >> remaining_flags). > > Sorry there is something I don't get here or there is something you > assume, maybe. > > How does this kind of design account for the case where you need > to change the biasing at runtime? > You're right, it doesn't. It only accounts for preconfiguring pins from device-tree of platform data.
Regards, Stijn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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