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    SubjectRe: PIXIS gpio controller and gpio flags
    On Mon, Jul 21, 2008 at 02:12:20PM -0700, Trent Piepho wrote:
    > On Mon, 21 Jul 2008, Anton Vorontsov wrote:
    > > On Sat, Jul 19, 2008 at 02:08:01PM -0700, Trent Piepho wrote:
    > >> It doesn't look like you have any way to unset the active low flag. What if
    > >> I unload the leds-gpio driver (or another gpio user) and then try to use the
    > >> gpio with something else? The active low flag is stuck on!
    > >
    > > Why would you want to unset the flags? It is specified in the device
    > > tree, and can't be changed. Specifying different flags for the same GPIO
    > > would be an error (plus, Linux forbids shared gpios, so you simply can't
    > > specify one gpio for several devices).
    >
    > You can't use the same gpio for two different things at the same time, but you
    > can load a driver, unload it, and then load another.

    Hm.. yeah, this might happen. Now I tend to think that transparent
    active-low handling wasn't that good idea after all. So, something like
    of_gpio_is_active_low(device_node, gpioidx) should be implemented
    instead. This function will parse the gpio's = <> flags. Please speak up
    if you have any better ideas though.


    Thanks for bringing this up,

    --
    Anton Vorontsov
    email: cbouatmailru@gmail.com
    irc://irc.freenode.net/bd2


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