Re: [PATCH 1/1] gpio: altera: Use handle_level_irq when configured as a level_high

From: Andy Shevchenko
Date: Fri Feb 17 2017 - 06:40:51 EST


On Fri, Feb 17, 2017 at 1:32 PM, Phil Reid <preid@xxxxxxxxxxxxxxxxx> wrote:
> On 17/02/2017 17:23, Andy Shevchenko wrote:
>>
>> On Fri, Feb 17, 2017 at 11:12 AM, Phil Reid <preid@xxxxxxxxxxxxxxxxx>
>> wrote:
>>>
>>> When a threaded irq handler is chained attached to one of the gpio
>>> pins when configure for level irq the altera_gpio_irq_leveL_high_handler
>>> does not mask the interrupt while being handled by the chained irq.
>>> This resulting in the threaded irq not getting enough cycles to complete
>>> quickly enough before the irq was disabled as faulty.
>>> It looks like handle_level_irq should be used in this situation
>>> instead of handle_simple_irq.
>>
>>
>>> @@ -310,7 +310,8 @@ static int altera_gpio_probe(struct platform_device
>>> *pdev)
>>> altera_gc->interrupt_trigger = reg;
>>>
>>> ret = gpiochip_irqchip_add(&altera_gc->mmchip.gc,
>>> &altera_irq_chip, 0,
>>> - handle_simple_irq, IRQ_TYPE_NONE);
>>> + altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH ?
>>> + handle_level_irq : handle_simple_irq, IRQ_TYPE_NONE);
>>
>>
>> AFAIK, handle_bad_irq() should be used here.
>>
> G'day Andy
>
> Grepping drivers/gpio find a combination of
> handle_simple_irq
> handle_level_irq
> handle_edge_irq
> handle_bad_irq
> used in gpiochip_irqchip_add

Try to add date of change and amount of use.
I bet handle_bad_irq() would be the winner.

> The ones which use handle_bad_irq call irq_set_handler_locked in their
> irq_type callback to either handle_level_irq / handle_edge_irq

Yep.

> So I think in this case it's correct. But I'm no expert.

I dunno.

--
With Best Regards,
Andy Shevchenko