On Thursday 05 July 2012, Sebastian Hesselbarth wrote:
> Andrew,
>
> is it possible to group all gpio banks into one DT description?
> For mach-dove it could be something like:
>
> gpio: gpio-controller {
> compatible = "marvell, orion-gpio";
> ...
>
> bank0@d0400 {
> reg = <0xd0400 0x40>;
> ngpio = <8>;
> mask-offset = <0>;
> interrupts = <12>;
> };
>
> bank1@d0400 {
> reg = <0xd0400 0x40>;
> ngpio = <8>;
> mask-offset = <8>;
> interrupts = <13>;
> };
This way you have multiple nodes with the same register
and different names, which is not how it normally works.
>
> This would have the advantage that DT describes gpio-to-irq dependencies.
> Moreover, nodes that reference gpios can do gpios = <&gpio 71 0>; instead of
> gpios = <&gpio3 7 0>;
Is that desired?
The device tree representation should match what is in the data sheet
normally. If they are in a single continuous number range, then we should
probably have a single device node with multiple register ranges
rather than one device node for each 32-bit register. Looking at
arch/arm/plat-orion/gpio.c I think that is not actually the case though
and having separate banks is more logical.
Something completely different I just noticed in the original patch:
> @@ -90,6 +74,27 @@ static void pmu_irq_handler(unsigned int irq, struct irq_desc *desc)
> }
> }
>
> +static int __initdata gpio0_irqs[4] = {
> + IRQ_DOVE_GPIO_0_7,
> + IRQ_DOVE_GPIO_8_15,
> + IRQ_DOVE_GPIO_16_23,
> + IRQ_DOVE_GPIO_24_31,
> +};
> +
> +static int __initdata gpio1_irqs[4] = {
> + IRQ_DOVE_HIGH_GPIO,
> + 0,
> + 0,
> + 0,
> +};
I think the latter one needs to be
+static int __initdata gpio1_irqs[4] = {
+ IRQ_DOVE_HIGH_GPIO,
+ IRQ_DOVE_HIGH_GPIO,
+ IRQ_DOVE_HIGH_GPIO,
+ IRQ_DOVE_HIGH_GPIO,
+};
so we register all four parts to the same primary IRQ. The
same is true for the devicetree representation.
Arnd
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