On Wed, Mar 5, 2014 at 11:49 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > On Tue, Feb 25, 2014 at 12:00 AM, Mika Westerberg > <mika.westerberg@xxxxxxxxxxxxxxx> wrote: > >> Sometimes it is useful to allow GPIO chips themselves to request GPIOs they >> own through gpiolib API. One usecase is ACPI ASL code that should be able >> to toggle GPIOs through GPIO operation regions. >> >> We can't really use gpio_request() and its counterparts because it will pin >> the module to the kernel forever (as it calls module_get()). Instead we >> provide a gpiolib internal functions gpiochip_request/free_own_desc() that >> work the same as gpio_request() but don't manipulate module refrence count. >> >> Since it's the GPIO chip driver who requests the GPIOs in the first place >> we can be sure that it cannot be unloaded without the driver knowing about >> that. Furthermore we only limit this functionality to be available only >> inside gpiolib. >> >> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > > I fully trust you in doing the ACPI stuff in patches 2-n but on this patch > in particular I want Alexandre's review tag as well, as he's working > actively with the descriptor API and I don't want to add too many quirks > without his consent. > > So Alexandre, what do you say about this? I will wait for v2 to give it a real review, but since the new functions are not exposed outside of gpiolib and the patch seems to serve a real purpose I have no objection to it. Especially if Rafael's suggestions can be applied. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
