Re: [PATCH v6 3/6] rust: irq: add support for non-threaded IRQs and handlers

[Alice Ryhl <aliceryhl@google.com>]

On Sat, Jul 19, 2025 at 7:47 AM Dirk Behme <dirk.behme@gmail.com> wrote:
>
> Hi Daniel,
>
> On 13.07.25 17:32, Daniel Almeida wrote:
> >
> >
> >> On 13 Jul 2025, at 12:28, Daniel Almeida <daniel.almeida@collabora.com> wrote:
> >>
> >>
> >>
> >>>
> >>> (2) Owning a reference count of a device (i.e. ARef<Device>) does *not*
> >>>     guarantee that the device is bound. You can own a reference count to the
> >>>     device object way beyond it being bound. Instead, the guarantee comes from
> >>>     the scope.
> >>>
> >>>     In this case, the scope is the IRQ callback, since the irq::Registration
> >>>     guarantees to call and complete free_irq() before the underlying bus
> >>>     device is unbound.
> >>>
> >>
> >>
> >> Oh, I see. I guess this is where I started to get a bit confused indeed.
> >>
> >> — Daniel
> >
> > Fine, I guess I can submit a newer version and test that on Tyr.
> >
> > Dirk, can you also test the next iteration on your driver? It will possibly
> > solve your use case as well.
>
>
> Now, I'm slightly confused ;) I just saw your version 7 of this
>
> [PATCH v7 3/6] rust: irq: add support for non-threaded IRQs and handlers
> https://lore.kernel.org/rust-for-linux/20250715-topics-tyr-request_irq2-v7-3-d469c0f37c07@collabora.com/
>
> and somehow was expecting something like
>
> fn handle(&self, dev: &Device<Bound>) -> IrqReturn
>
> there. I.e. to get a bound device passed into the handler.
>
> If I misunderstood the discussion and this is supposed to not be
> added: Any hint how to get the &Device<Bound> from the probe
> function/irq registration into the irq handler, then? To be able to do
> something like
>
> fn handle(&self) -> IrqReturn {
>   let dev = ??;
>   let io = self.iomem.access(dev);

Please see:
https://lore.kernel.org/all/CAH5fLgibCtmgFpKNrC+jcSEqSUctyVMuYwEC0QSo+vzyDXK0zg@mail.gmail.com/

Alice