Re: [PATCH v2 08/17] gpio: locomo: implement per-pin irq handling

Linus Walleij
2015-05-12T11:15:25Z

On Wed, May 6, 2015 at 6:42 PM, Dmitry Eremin-Solenikov
<dbaryshkov@gmail.com> wrote:
> 2015-05-06 17:15 GMT+03:00 Linus Walleij <linus.walleij@linaro.org>:
>> On Tue, Apr 28, 2015 at 1:55 AM, Dmitry Eremin-Solenikov
>> <dbaryshkov@gmail.com> wrote:
>>
>>> LoCoMo has a possibility to generate per-GPIO edge irqs. Support for
>>> that was there in old locomo driver, got 'cleaned up' during old driver
>>> IRQ cascading cleanup and is now reimplemented. It is expected that
>>> SL-5500 (collie) will use locomo gpio irqs for mmc detection irq.
>>>
>>> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
>>
>> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
>
> Thanks for review of the patches.
>
>> Assume this will also go through MFD.
>>
>>> + irq_set_chained_handler(lg->irq, NULL);
>>> + irq_set_handler_data(lg->irq, NULL);
>>
>> Why is this needed? If the GPIOLIB_IRQCHIP code in
>> gpiolib.c is not doing this then maybe it's the core code that
>> needs fixing rather than having this in the driver.
>
> I have skimmed through the rest of drivers using
> gpiochip_set_chained_irqchip(). Indeed none of the drivers NULL
> the chained handled and handler data. However I couldn't locate
> the code where they would be cleared.
>
> Should I still send the patch fixing the GPIOLIB_IRQCHIP?

Yes I guess you need to save parent_irq in struct gpio_chip and
remove it in gpiochip_irqchip_remove() if it's != 0.

Yours,
Linus Walleij