Re: [PATCH 0/2] change "client->irq >= 0" to "client->irq > 0"

[Alexandre Belloni <alexandre.belloni@free-electrons.com>]

On 03/06/2015 at 20:05:56 +0300, Octavian Purdila wrote :
> On Wed, Jun 3, 2015 at 2:02 PM, Alexandre Belloni
> <alexandre.belloni@free-electrons.com> wrote:
> > On 03/06/2015 at 00:34:11 +0300, Octavian Purdila wrote :
> >> This fixes an issue introduces by commit dab472eb931b ("i2c / ACPI:
> >> Use 0 to indicate that device does not have interrupt assigned") where
> >> drivers will try to request IRQ 0 when no GpioInt is defined in ACPI.
> >>
> >> The same issue occurs when the device is instantiated via device tree
> >> with no IRQ, or from the i2c sysfs interface, even before the patch
> >> above.
> >>
> >> Linus, since the commit above was already merged in the GPIO tree,
> >> should these fixes be merged also via the GPIO tree (with ACKs from
> >> the others subsystem maintainers)?
> >>
> >
> > Side question, has it been considered that IRQ 0 is valid on some
> > platform and that means i2c devices will not be able to be wired to that
> > IRQ anymore? Though, I don't think there are any existing design that
> > does so.
> >
> 
> Device tree instantiation does not allow you to used IRQ 0 anyway. And
> here is what Linus said about this:
> 
> http://yarchive.net/comp/linux/no_irq.html

I'm pretty sure his point doesn't hold anymore 10 years later. I don't
believe ARM is "the small percentage of a small percentage of a small
percentage" anymore and it is probably more tested than it was at the
time. Anyway, I'm fine with the change, you can add my
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
for your v2.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com