[PATCH 0/9] ARM: sa1100: Rework IRQ handling

[Dmitry Eremin-Solenikov]

On Fri, Nov 22, 2013 at 9:58 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Wed, Nov 20, 2013 at 04:45:40AM +0400, Dmitry Eremin-Solenikov wrote:
>> On Wed, Nov 20, 2013 at 4:20 AM, Russell King - ARM Linux
>> <linux at arm.linux.org.uk> wrote:
>> > Also note that we _do_ have sa11x0 platforms which request their GPIOs
>> > in their arch_initcall callback, so the sa11x0 GPIO driver better be
>> > around at that point otherwise things *will* fail.
>>
>> Which ones if you have them in your mind?
>>
>> > I suspect that means the SA11x0 GPIO driver must be initialised early.
>>
>> Anyway in these patches gpio-sa1100 driver is registered at postcore
>> initcall, so gpios should
>> be available before arch_initcall functions.
>
> No it won't - quite simply because the platforms get called before
> sa1100_init() is run - they have to be because the platforms get to
> customise the platform data passed to the SA11x0 devices, which has
> to happen before sa1100_init() registers the devices.

They both belong to arch_initicall level, aren't they? So ordering is guarded
only by having customize_machine(which calls init_machine) from arch/arm/kernel/
before sa1100_init from arch/arm/mach-sa1100/?

> By adding the GPIO device to the sa11x0_devices list, you're registering
> it afterwards which means that the GPIO driver isn't up and running
> at this time.  That means that various platforms (such as the h3xxx
> ones which call gpio_request on built-in GPIOs at this time) will fail.

For sa1100 there are only 2.5 platforms which use gpiolib - collie and h3xxx.
(The half is for simpad, which registers gpio chip from platform code, but
doesn't use it otherwise -- in platform code, of course).

Collie is changed not to call gpio_to_irq at init_machine time.
Separate patchset
reworks h3xxx (I missed them first time) to call gpio_* functions later.

-- 
With best wishes
Dmitry