Re: [Regression] "irqdomain: Don't set type when mapping an IRQ" breaks nexus7 gpio buttons

[Marc Zyngier <marc.zyngier@arm.com>]

On 11/08/16 10:47, Jon Hunter wrote:
> 
> On 11/08/16 09:37, Marc Zyngier wrote:
>> On 08/08/16 22:48, Linus Walleij wrote:
>>> On Sat, Aug 6, 2016 at 1:45 AM, John Stultz <john.stultz@linaro.org> wrote:
>>>
>>>> @@ -614,7 +615,11 @@ unsigned int irq_create_fwspec_mapping(struct
>>>> irq_fwspec *fwspec)
>>>>                  * it now and return the interrupt number.
>>>>                  */
>>>>                 if (irq_get_trigger_type(virq) == IRQ_TYPE_NONE) {
>>>> -                       irq_set_irq_type(virq, type);
>>>> +                       irq_data = irq_get_irq_data(virq);
>>>> +                       if (!irq_data)
>>>> +                               return 0;
>>>> +
>>>> +                       irqd_set_trigger_type(irq_data, type);
>>>>                         return virq;
>>>>                 }
>>>>
>>>> If I revert just that, it works again.
>>>
>>> This makes my platform work too.
>>> Tested-by: Linus Walleij <linus.walleij@linaro.org>
>>
>> Hmmm. I'm now booting your kernel on the APQ8060, and reverting this
>> hunk doesn't fix it for me. I'm confused...
>>
>> The interesting part is this:
>> 109:     100000          0   msmgpio  88 Level     (null)
> 
> 88 is the pm8058 parent interrupt and so I am surprised you would even
> see this in /proc/interrupts as it should be a chained interrupt, right?
> 
> Are you seeing this with all the ethernet updates for the APQ8060 in
> Linus' branch? I am curious what you see with stock v4.8-rc1 and if
> interrupts work ok with the change I had proposed. Hard to tell if there
> is more than one issue here.

Nailed the sucker:

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index b4c1bc7..9d7284a 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -820,6 +820,18 @@ __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
 	desc->name = name;
 
 	if (handle != handle_bad_irq && is_chained) {
+		int ret;
+
+		ret = __irq_set_trigger(desc,
+					irqd_get_trigger_type(&desc->irq_data));
+		WARN_ON(ret);
+		/*
+		 * This is beyond ugly: .set_type may have overridden
+		 * the flow, not not knowing that we're dealing with a
+		 * chained handler. Reset it here because we know
+		 * better.
+		 */
+		desc->handle_irq = handle;
 		irq_settings_set_noprobe(desc);
 		irq_settings_set_norequest(desc);
 		irq_settings_set_nothread(desc);

Linus, Jon: Can you please confirm this fixes your respective issues?

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...