On Fri, Aug 30, 2013 at 9:55 PM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote: > On 08/29/2013 06:24 PM, Javier Martinez Canillas wrote: > ... >> We have been trying to solve this issue for a few months by now and Linus' >> approach seems to be the most sensible solution to me. >> >> Drivers that request an IRQ and assume that platform code will request and setup >> the GPIO have been broken since the boards using these drivers were migrated to >> DT (e.g: smsc911x on OMAP2+ boards). > > That's only true if the driver for the GPIO controller is buggy. > Whatever request_irq() maps down to in the GPIO/IRQ controller driver > simply needs to set up the pin as an interrupt input, then it doesn't > matter which order the driver does things. As mentioned it can't do that, because doing that creates a restriction on which order the driver does things... But you mentioned that you wanted an API that would account for the case where the *same driver* requested the same resource (a GPIO line) to be used for both IRQ and GPIO, through two different calls. I would be happy to see how we could do that, preferably in a generic way. Since the gpio_request() does not contain the signature of the calling driver I don't see how we could do this without refactoring the whole world. In that case it would probably be easiest to *first* proceed to complete Alexandre's suggested refactorings for GPIO descriptors, which tie down GPIOs to be requested like clocks and regulators and thus tied to a device, so we can from there proceed to implement such a conditional request, as we will then have the required information in the GPIO subsystem. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
