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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 5 Dec 2020 21:15:29 +0100
From:   "Enrico Weigelt, metux IT consult" <lkml@...ux.net>
To:     "Enrico Weigelt, metux IT consult" <info@...ux.net>,
        linux-kernel@...r.kernel.org
Cc:     corbet@....net, linus.walleij@...aro.org,
        bgolaszewski@...libre.com, mst@...hat.com, jasowang@...hat.com,
        linux-doc@...r.kernel.org, linux-gpio@...r.kernel.org,
        virtualization@...ts.linux-foundation.org,
        linux-riscv@...ts.infradead.org
Subject: Howto listen to/handle gpio state changes ? Re: [PATCH v2 2/2]
 drivers: gpio: add virtio-gpio guest driver

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@...ux.net -- +49-151-27565287