On Thu, Dec 6, 2012 at 8:45 AM, Alexandre Courbot <acourbot@xxxxxxxxxx> wrote: > With the current API, GPIOs are manipulated through an integer which > represents their unique number across the system. This poses problems in > terms of portability, scalability and flexibility: for instance, the > number of valid GPIOs for a given system is fixed at system time, and a > large array of that size is statically allocated to hold the GPIO > descriptors. Worse, GPIOs can be used without being properly allocated. > > In order to improve the situation, the integer namespace must first get > away. This patch introduces an alternative GPIO API that uses opaque > handlers and refactor gpiolib's internals to work with these handlers > instead of GPIO numbers. The former integer-based API is still available > as a light wrapper around this new API. > > This first step will then us to build more improvements for gpiolib, > like proper GPIO lookup functions per device and provider, and getting > rid of the static GPIO array and the ARCH_NR_GPIO configuration option. > > Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx> I really like this. It is looking very good. Especially it's nice that it makes GPIO descriptors the norm rather than a bolt-on, and the old linear GPIO space is turned into a comaptibility layer using static inlines. I'd like to see some love for Documentation/gpio.txt to reflect the changes, plus considering Grants note, and I will be happy to add Reviewed-by on this. Especially the lookups will be nice to see going forward! Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
