Messages in this thread | | | Date | Thu, 12 Sep 2013 17:57:00 +0200 | From | Alexander Holler <> | Subject | Re: [PATCH] RFC: interrupt consistency check for OF GPIO IRQs |
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Am 12.09.2013 17:19, schrieb Stephen Warren: > > IRQs, DMA channels, and GPIOs are all different things. Their bindings > are defined independently. While it's good to define new types of > bindings consistently with other bindings, this hasn't always happened, > so you can make zero assumptions about the IRQ bindings by reading the > documentation for any other kind of binding. > > Multiple interrupts are defined as follows: > > // Optional; otherwise inherited from parent/grand-parent/... > interrupt-parent = <&gpio6>; > // Must be in a fixed order, unless binding defines that the > // optional interrupt-names property is to be used. > interrupts = <1 IRQF_TRIGGER_HIGH> <2 IRQF_TRIGGER_LOW>; > // Optional; binding for device defines whether it must > // be present > interrupt-names = "foo", "bar"; > > If you need multiple interrupts, each with a different parent, you need > to use an interrupt-map property (Google it for a more complete > explanation I guess). Unlike "interrupts", "interrupt-map" has a phandle > in each entry, and hence each entry can refer to a different IRQ > controller. You end up defining a dummy interrupt controller node (which > may be the leaf node with multiple IRQ outputs, which then points at > itself as the interrupt parent), pointing the leaf node's > interrupt-parent at that node, and then having interrupt-map "demux" the > N interrupt outputs to the various interrupt controllers. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
What a mess. I assume that is the price that bindings don't have to change.
Thanks for clarifying that,
Alexander Holler
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