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

[Jon Hunter <jonathanh@nvidia.com>]

On 11/08/16 13:46, Marc Zyngier wrote:
> 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:

Great!

> 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);

You could wrap the entire call in the WARN_ON(). I was not sure if there
was a better way to handle that.

> +		/*
> +		 * 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;

Yes I see the call to irq_set_handler in the pinctrl-msm.c set_type.
Good catch!

Apart from the above ...

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

-- 
nvpublic