On Wed, Feb 27, 2013 at 6:50 PM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote: > On 02/26/2013 08:57 PM, Javier Martinez Canillas wrote: >> On Wed, Feb 27, 2013 at 2:07 AM, Jon Hunter <jon-hunter@xxxxxx> wrote: >>> >>> On 02/26/2013 06:13 PM, Stephen Warren wrote: >>>> On 02/26/2013 04:45 PM, Jon Hunter wrote: > ... >>>>> One issue I see is that by not calling gpio_request, then potentially >>>>> you could have someone request a gpio via gpio_request() and someone >>>>> trying to use it as an interrupt source via request_irq(). Now obviously >>>>> that represents a bug because there is only one physical gpio, but I >>>>> gather it is something we need to protect against. >>>> >>>> I'm not sure it's really that much of an issue, but presumably the >>>> solution is for a combined GPIO+IRQ driver to simply call gpio_request >>>> internally from within some irq_chip function. It looks like struct >>>> irq_chip doesn't have a request/free, but perhaps they could be added to >>>> solve this? >>> >>> Yes I was wondering if we could do something like that. That would work, >>> may be that's what we should propose. >> >> Something like that would definitely solve the GPIO request issue but >> we still have the issue that the current OMAP GPIO controller binding >> does not support #interrupt-cells = <2>. > > The binding documentation in > Documentation/devicetree/bindings/gpio/gpio-omap.txt indicates that it > does. If this doesn't work in practice, it's a driver bug that can > presumably be easily fixed. And no need to change any ABI definitions:-) > indeed :-) In fact I think that some documentation bits were borrowed from the NVIDIA Tegra GPIO controller bindings but it was never implemented in the OMAP GPIO driver to parse the second interrupt-cell which should specify the flags. > BTW, I notice in that binding document that the description of the two > cells for #interrupt-cells is actually part of the description of the > "interrupt-controller" property; it should be moved up one line really. Right, will submit a patch to fix this. Best regards, Javier -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
