Re: [PATCH v3] thermal: rcar_thermal: Use platform_get_irq_optional() to get the interrupt

[Andy Shevchenko]

On Thu, Jan 6, 2022 at 5:29 PM Niklas Söderlund
<niklas.soderlund@xxxxxxxxxxxx> wrote:
> On 2022-01-05 19:25:25 +0000, Lad, Prabhakar wrote:
> > On Wed, Jan 5, 2022 at 7:13 PM Niklas Söderlund
> > <niklas.soderlund@xxxxxxxxxxxx> wrote:
> > > On 2022-01-04 14:52:11 +0000, Lad Prabhakar wrote:

...

> > > > +             if (!irq || irq == -ENXIO)
> > > > +                     break;
> > >
> > > This do not look correct and differs form v1.
> > >
> > > In the old code if we can't get an IRQ the loop is continued. This is
> > > used to detect if interrupts are supported or not on the platform.  This
> > > change will fail on all systems that don't describes interrupts in DT
> > > while the driver can function without interrupts.
> > >
> > There are no non-DT users for this driver. Do you see this driver
> > being used in a non-DT environment in near future?
>
> No, maybe I was unclear sorry about that. What I intended to say was
> that this change will break platforms that that make use of this driver
> but do not describe interrupts in its DT description. As with this
> change not describing interrupts is consider an error.
>
> For example checkout thermal@ffc48000 in arch/arm/boot/dts/r8a7779.dtsi.

> > > Is there a reason you wish to do this change in addition to the switch
> > > to platform_get_irq_optional()? If so I think that should be done in a
> > > separate patch.
> > >
> > No other reason, It was suggested by Gerrt too to use a break instead
> > of continue in v1.
>
> I think we need to keep the original behavior.

I don't see how this can break those. Or are you stating that some of
them are using board files with 0 as a valid (v)IRQ?

-- 
With Best Regards,
Andy Shevchenko