Am Mittwoch, 2. Oktober 2013, 12:40:14 schrieb Linus Walleij: > On Fri, Sep 27, 2013 at 6:06 PM, Stephen Warren <swar...@wwwdotorg.org> wrote: > > [Laxman] > > > >> Hmm.. When I added the PIN_DEFAULT, I just though that do not update > >> anything in the register and implemented like that. > >> There is nothing "default" option in HW. > > > > The description of that pinconfig option is: > >> 7970cb77 (Heiko Stübner 2013-06-06 16:44:25 +0200 43) * > >> @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down > >> based 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 44) * > >> on embedded knowledge of the controller hardware, like current mux > >> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 45) * > >> function. The pull direction and possibly strength too will normally > >> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 46) * be > >> decided completely inside the hardware block and not be readable > >> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 47) * from > >> the kernel side. 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 > >> 48) * If the argument is != 0 pull up/down is enabled, if it is 0, > >> the 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 49) * > >> configuration is ignored. The proper way to disable it is to use > >> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 50) * > >> @PIN_CONFIG_BIAS_DISABLE. > > > > If the HW doesn't support any concept of a default pull, I think the > > driver shouldn't support that option; it should return an error if asked > > to program it. > > Yes that's how I remember it and how we specified it. > Correct Heiko?
Correct. The option was/is meant for hardware that sets pull settings without telling the kernel specifics and the kernel also not being able to influence them. Heiko -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
