| Subject | Re: [PATCH 00/13] Ingenic JZ4740 / JZ4780 pinctrl driver | Date | Fri, 20 Jan 2017 11:17:28 +0100 | From | Paul Cercueil <> |
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Le 2017-01-20 09:40, Linus Walleij a écrit :
> On Thu, Jan 19, 2017 at 12:19 PM, Paul Cercueil <paul@crapouillou.net> > wrote: > >> The problem with pinctrl and PWM, is that the pinctrl API works by >> "states". A default state, sleep state, and basically any custom state >> that the devicetree provides. This works well until you need to >> control individually each pin; with 8 pins, you would need 2^8 states, >> each one corresponding to a given configuration. > > I do not really understand, do you really use all 2^8 states in a given > system? > > The pin control states are to be used for practical situations, not > for all theoretical situations. > > You should define in your device tree the states that your > particular system will use. Not all possible states on all possible > systems. >
Well, that was if I wanted to dynamically set/unset the pin mux and configuration when requesting/freeing a PWM. Then I'd need 2^x states for X PWM pins.
Anyway, a static configuration works for me too. If at some point I want dynamic configuration of the pins then I'll make the PWM driver handle only one PWM pin and create one driver instance for each pin.
Regards, -Paul
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