On Mon, Mar 30, 2015 at 12:52 PM, Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> wrote: > On Fri, Mar 27, 2015 at 11:36:25AM +0100, Linus Walleij wrote: >> On Fri, Mar 27, 2015 at 11:06 AM, Mika Westerberg >> <mika.westerberg@xxxxxxxxxxxxxxx> wrote: >> > On Thu, Mar 26, 2015 at 06:28:19PM +0200, Octavian Purdila wrote: >> >> >> For the sleep case I think the GPIO controller needs to do the pin >> >> enable and set input direction operation in it's irq_bus_sync_unlock. >> > >> > I wonder how DT handles all this? Is it the boot firmware that sets up >> > the pins accordingly or is there something we are missing? >> >> DT systems mostly do not have firmware for power usecases, they >> handle it all using pin control. I would more say that is a feature of >> all-SW systems without power-firmware ideas, without ACPI and >> without PSCI (well PSCI systems do not care about much more >> than CPU power down in firmware anyway...) > > OK, thanks. > > In case of ACPI (where firmware does lot more) it is supposed to > configure pins based on what is connected, if the firmware knows that. > Due to bugs in the boot firmware that obviously does not happen in all > cases (like this one). > Ah, interesting, I was not aware that the firmware was supposed to do the pin configuration. In this case I think your patch can be merged as it is Mika, mine doesn't make sense anymore. This particular case is special since we did not performed the tests on a full system that has the component integrated. We instead used and I2C to USB bridge to which we connected the component and we loaded the ACPI table dynamically. > If we want to support requesting IRQ directly through irqchip interface > on ACPI systems there needs to be some way the GPIO/pinctrl core can use > to turn the pin as input, GPIO mode. > > Octavian's patch does that but not sure if it is good idea for non-ACPI > systems as they already work. We could also do the same in GPIO/irqchip > drivers but there is no guarantee for the caller that it is done. IMHO > safest option is to explictly request the GPIO, turn it input and then > convert the GPIO to interrupt. That way we know the pin is configured > just like we expect. > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
