Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH 0/4] gpio: introduce descriptor-based interface | Date | Mon, 14 Jan 2013 10:46:12 +0000 |
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On Monday 14 January 2013, Alex Courbot wrote: > On 01/10/2013 07:08 PM, Arnd Bergmann wrote: > > I found two that provide the generic gpio interfaces when gpiolib > > is disabled, but use gpiolib otherwise for the same hardware, > > arch/m68k/include/asm/mcfgpio.h and arch/blackfin/include/asm/gpio.h. > > I would assume that we can simply remove the non-gpiolib shortcut > > here at cost of a small overhead. > > I performed a search on my side too (checking configurations options > which select GENERIC_GPIO but not ARCH_REQUIRE_GPIOLIB) and found the > same list. This takes some time btw - many platforms use this combo to > make GPIO support optional. Can I ask how you figured out these two archs?
I basically grepped for GENERIC_GPIO and looked at the individual implementations.
> > Then there are a bunch that use gpiolib but have a nontrivial > > implementation of gpio_get_value and other functions. I'm not sure > > if these are a problematic with your code. > > AFAICT these all implement an inline path that bypasses GPIOlib when the > GPIO number is known at compile time, for faster bitbanging I presume. > It should be totally harmless to keep them. Unfortunately, I don't think > it would be possible to have a similar trick using handlers.
Right, makes sense.
Arnd
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