Re: [PATCH/RFC] drivers/irqchip: add irq-inverter

From: Marc Zyngier
Date: Thu Dec 30 2021 - 05:37:09 EST


On Wed, 29 Dec 2021 19:52:18 +0000,
Nikita Yushchenko <nikita.yoush@xxxxxxxxxxxxxxxxxx> wrote:
>
> Hi
>
> >>> The right way to do it is to use the existing API by exposing the
> >>> inverter (there are existing examples in the tree, using the
> >>> hierarchical model)...
> >
> > A much simpler version can be written in a few minutes, see below...
>
> Can something like that be used if the parent domain is not
> hierarchical (i.e. does not provide alloc(), but provides map()
> instead)?

No. This definitely relies on the parent being hierarchical, as that's
exactly what it was designed for the first place.

> In particular, gpio-rcar currently provides irq domain that is not
> hierarchical. As well as quite a few other gpiochips.

Well, you just found yourself some useful work! ;-)

M.

--
Without deviation from the norm, progress is not possible.