Messages in this thread | | | From | Geert Uytterhoeven <> | Date | Tue, 5 Oct 2021 08:52:59 +0200 | Subject | Re: [PATCH] gpio: aggregator: Add interrupt support |
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Hi Viresh,
On Tue, Oct 5, 2021 at 7:50 AM Viresh Kumar <viresh.kumar@linaro.org> wrote: > On 04-10-21, 14:44, Geert Uytterhoeven wrote: > > Currently the GPIO Aggregator does not support interrupts. This means > > that kernel drivers going from a GPIO to an IRQ using gpiod_to_irq(), > > and userspace applications using line events do not work. > > > > Add interrupt support by providing a gpio_chip.to_irq() callback, which > > just calls into the parent GPIO controller. > > > > Note that this does not implement full interrupt controller (irq_chip) > > support, so using e.g. gpio-keys with "interrupts" instead of "gpios" > > still does not work. > > Thanks for looking into this. I am not sure of the difference it makes > with and without full irq-chip, but lemme explain the use case that we > are concerned about with virtio. > > Eventually the interrupt should be visible to userspace, with > something like libgpiod. Which can then send the information over > virtio to the guest.
Exactly, that was what I had in mind, too.
> Will the interrupts be visible in userspace with your patch ?
Yes they are. Before, gpiomon (test app from libgpiod) didn't work, now it does.
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
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