On Wed, May 13, 2015 at 4:58 AM, Linus Walleij [off-list ref] wrote:

On Wed, May 13, 2015 at 4:25 AM, Feng Kan [off-list ref] wrote:

quoted

Marc:

Sorry for top posting. It seems with GIC-400, the get_irqstate is not a reliable
way of accessing the GPIO status. In our case, the gpio interrupt status can
only be read correctly with the SPISR register. So it seems we have to go
back to the old way of mapping the SPISR portion of the GIC in our GPIO
driver. We wanted to ask you if that is acceptable since SPISR in not
standard in all GIC, perhaps we can treat it differently.

As GPIO maintainer I am curious about what this is...

Can you describe the scenario where your GPIO (!) driver needs
to be poking around in the GIC SPISR?

We are using the gpio driver with gpio_key for power button. The gpio
status can only be retrieved from the GIC register when the gpio is
acting as a interrupt. Marc had provided a patch which allow the
getting of the irq status
using the PENDING_SET register, however it seems it is not reliable.
Another register in the GIC call the SPISR always give the correct
status but it is only available in the GIC-400 and hence not likely to
be incorporated into the general GIC code. We would like to go back
the version 1 of the patch and ioremap the region in the gpio driver
and access the status that way. Please let us know what you think.

Yours,
Linus Walleij