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

[Bjorn Andersson]

On Thu 11 Aug 05:46 PDT 2016, 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@xxxxxxxxxx> 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@xxxxxxxxxx>
> >>
> >> 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.
> +		 */

Thanks for this Marc!

But it makes me (author of pinctrl-msm) wonder, am I supposed to not
implement .set_type like this for handling the transition between edge
and level handlers?

Regards,
Bjorn