[linux-meson] Re: [PATCH v2 3/5] pinctrl: meson: enable GPIO IRQs

On Tue, Nov 24, 2015 at 10:04 AM, Carlo Caione [off-list ref] wrote:

On Tue, Nov 24, 2015 at 9:28 AM, Marc Zyngier [off-list ref] wrote:

quoted

[...]

quoted

+     for (i = 0; i < pc->num_gic_irqs; i++) {
+             struct of_phandle_args oirq;
+
+             of_irq_parse_one(node, i, &oirq);
+             irq_of_phandle_args_to_fwspec(&oirq, &pc->gic_irqs[i]);
+
+             pc->irq_map[i] = IRQ_FREE;
+     }

The whole thing feels weird. Why do you need to keep a set of fwspecs?

We only have 8 IRQs on the GIC side that we can use for the GPIOs. The
set of fwspec is used to track these IRQs.
At probe time we read from the DTS how many and which IRQs are
reserved on the GIC for the GPIOs. Every time a GPIO IRQ is installed,
we use one of these IRQ lines.

quoted

All you need is a range of interrupts that would be conveniently
represented by a bitmap (assuming your interrupts space is a mostly
contiguous range).

I could do that but it feels to me like we end up hiding from the DTS
some information that naturally should be in there: a pinctrl device
that is using 8 interrupt lines of its interrupt controller. IMO this
is not a special case that requires some special treatment.

Marc,
What's your opinion on this? So I can start cooking v3

Thanks,

-- 
Carlo Caione