Messages in this thread | | | From | Laurent Pinchart <> | Subject | Re: How to create IRQ mappings in a GPIO driver that doesn't control its IRQ domain ? | Date | Thu, 25 Jul 2013 11:45:33 +0200 |
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Hi Linus,
Thank you for your answer.
On Thursday 25 July 2013 11:20:54 Linus Walleij wrote: > On Wed, Jul 24, 2013 at 1:21 AM, Laurent Pinchart wrote: > > Has anyone run into a similar issue ? My gut feeling is that the > > architecture isn't right somewhere, but I can't really pinpoint where. > > We had a similar situation with the MFDs, where Mark, Lee and Sam came up > with the solution to include an irqdomain in the MFD cell spawn function: > > extern int mfd_add_devices(struct device *parent, int id, > struct mfd_cell *cells, int n_devs, > struct resource *mem_base, > int irq_base, struct irq_domain *irq_domain); > > When each cell (i.e. a platform device) is created, the irq for that cell > will be translated with irq_create_mapping() so the cell/platform device > just get a Linux IRQ it can use and do not need to worry about translating > it. > > Prior to this we had all sorts of exported translator functions for the IRQs > exported from each hub driver ---what a mess. > > Can you think about a parent/child relationship making it possible to pass > the irqs readily translated in this case?
The two devices are independent, so there's no real parent/child relationship. However, as Grant proposed, I could list all the interrupts associated with GPIOs in the GPIO controller DT node. I would then just call irq_of_parse_and_map() in the .to_irq() handler to magically translate the GPIO number to a mapped IRQ number.
The number of interrupts can be pretty high (up to 58 in the worst case so far), so an alternative would be to specify the interrupt-parent only, and call irq_create_of_mapping() directly. What solution would you prefer ?
-- Regards,
Laurent Pinchart
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