Re: [PATCH] ata: Don't use NO_IRQ in pata_of_platform driver

Anton Vorontsov
2011-12-05T20:21:33Z

On Mon, Dec 05, 2011 at 01:16:39PM -0600, Rob Herring wrote:
[...]
> At least for DT enabled platforms, we could force "no irq" to be 0 in
> the DT irq code. Searching the dts files, I found 2 occurrences of IRQ0.

Please note that there are HW IRQ numbers and "Virtual" IRQ numbers.
dev->irq and thus the thing that we pass into request_irq() is a
virtual IRQ thing, a "cookie".

While in device tree you see real HW IRQ numbers.

Legal VIRQ is always > 0, while HW IRQ could be >= 0.

> Prima2 has timer on IRQ0, and VersatileAB has watchdog on IRQ0. Prima2
> should be fine currently as it doesn't use the of_irq_* functions to get
> the timer irq, but that is an issue as it skips any translation.
> VersatileAB should be okay with the VIC irqdomain support.

It shouldn't be an issue to use of_irq_*() functions for these IRQs.
of_irq_*() will remap HW IRQ 0 to some other VIRQ. If it does not do
this currently, then it's a bug and should be fixed.

Thanks,

--
Anton Vorontsov
Email: cbouatmailru@gmail.com