linux-kernel - Re: [PATCH] gpio: Wakeup gpio controller when it is used as IRQ controller

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Date:   Wed, 20 Sep 2017 15:07:17 -0500
From:   Grygorii Strashko <grygorii.strashko@...com>
To:     Michal Simek <michal.simek@...inx.com>,
        <linux-kernel@...r.kernel.org>, <monstr@...str.eu>
CC:     Borsodi Petr <Petr.Borsodi@...z>,
        Linus Walleij <linus.walleij@...aro.org>,
        <linux-gpio@...r.kernel.org>, Jon Hunter <jonathanh@...dia.com>
Subject: Re: [PATCH] gpio: Wakeup gpio controller when it is used as IRQ
 controller



On 09/20/2017 02:14 AM, Michal Simek wrote:
> From: Borsodi Petr <Petr.Borsodi@...z>
> 
> There is a problem with GPIO driver when used as IRQ controller.
> It is not working because the module is sleeping (clock is disabled).
> The patch enables clocks when IP is used as IRQ controller.

I think, it should be solved already in genirq core.
commit be45beb "genirq: Add runtime power management support for IRQ chips"


> 
> Signed-off-by: Borsodi Petr <Petr.Borsodi@...z>
> Signed-off-by: Michal Simek <michal.simek@...inx.com>
> ---
> 
> Based on discussion with Linus here https://lkml.org/lkml/2017/8/22/400
> ---
>   drivers/gpio/gpiolib.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index eb80dac4e26a..17258ad1fadb 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1676,14 +1676,22 @@ static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
>   static int gpiochip_irq_reqres(struct irq_data *d)
>   {
>   	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
> +	int ret;
>   
>   	if (!try_module_get(chip->gpiodev->owner))
>   		return -ENODEV;
>   
> +	ret = pm_runtime_get_sync(chip->parent);
> +	if (ret < 0) {
> +		module_put(chip->gpiodev->owner);
> +		return ret;
> +	}
> +
>   	if (gpiochip_lock_as_irq(chip, d->hwirq)) {
>   		chip_err(chip,
>   			"unable to lock HW IRQ %lu for IRQ\n",
>   			d->hwirq);
> +		pm_runtime_put(chip->parent);
>   		module_put(chip->gpiodev->owner);
>   		return -EINVAL;
>   	}
> @@ -1695,6 +1703,7 @@ static void gpiochip_irq_relres(struct irq_data *d)
>   	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
>   
>   	gpiochip_unlock_as_irq(chip, d->hwirq);
> +	pm_runtime_put(chip->parent);
>   	module_put(chip->gpiodev->owner);
>   }
>   
> 

-- 
regards,
-grygorii