Howto listen to/handle gpio state changes ? Re: [PATCH v2 2/2] drivers: gpio: add virtio-gpio guest driver

Enrico Weigelt, metux IT consult lkml at metux.net
Sat Dec 5 15:15:29 EST 2020


On 03.12.20 20:11, Enrico Weigelt, metux IT consult wrote:

Friends,

I've still got a problem w/ signal/irq handling:

The virtio-gpio device/host can raise a signal on line state change.
Kinda IRQ, but not actually running through real IRQs, instead by a
message running though queue. (hmm, kida MSI ? :o).

I've tried allocating an IRQ range and calling generic_handle_irq(),
but then I'm getting unhanled IRQ trap.

My hope was some gpio lib function for calling in when an line state
changes, that does all the magic (somebody listening on some gpio,
or gpio used as interrupt source), but the only thing I could find
was some helpers for gpio chips that have their own builtin
interrupt controller (VIRTIO_GPIO_EV_HOST_LEVEL).

Somehow feels that's not quite what I'm looking for.

Could anybody please give me more insights ?


--mtx

-- 
---
Hinweis: unverschlüsselte E-Mails können leicht abgehört und manipuliert
werden ! Für eine vertrauliche Kommunikation senden Sie bitte ihren
GPG/PGP-Schlüssel zu.
---
Enrico Weigelt, metux IT consult
Free software and Linux embedded engineering
info at metux.net -- +49-151-27565287



More information about the linux-riscv mailing list