[PATCH] gpio: max732x: Use irqchip template

[PATCH] gpio: max732x: Use irqchip template

[Linus Walleij]

This makes the driver use the irqchip template to assign
properties to the gpio_irq_chip instead of using the
explicit calls to gpiochip_irqchip_add_nested() and
gpiochip_set_nested_irqchip(). The irqchip is instead
added while adding the gpiochip.

Cc: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpio/gpio-max732x.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 63472f308857..347415344a20 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -503,6 +503,8 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 
 	if (((pdata && pdata->irq_base) || client->irq)
 			&& has_irq != INT_NONE) {
+		struct gpio_irq_chip *girq;
+
 		if (pdata)
 			irq_base = pdata->irq_base;
 		chip->irq_features = has_irq;
@@ -517,19 +519,17 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 				client->irq);
 			return ret;
 		}
-		ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
-						   &max732x_irq_chip,
-						   irq_base,
-						   handle_simple_irq,
-						   IRQ_TYPE_NONE);
-		if (ret) {
-			dev_err(&client->dev,
-				"could not connect irqchip to gpiochip\n");
-			return ret;
-		}
-		gpiochip_set_nested_irqchip(&chip->gpio_chip,
-					    &max732x_irq_chip,
-					    client->irq);
+
+		girq = &chip->gpio_chip.irq;
+		girq->chip = &max732x_irq_chip;
+		/* This will let us handle the parent IRQ in the driver */
+		girq->parent_handler = NULL;
+		girq->num_parents = 0;
+		girq->parents = NULL;
+		girq->default_type = IRQ_TYPE_NONE;
+		girq->handler = handle_simple_irq;
+		girq->threaded = true;
+		girq->first = irq_base; /* FIXME: get rid of this */
 	}
 
 	return 0;
-- 
2.26.2

Re: [PATCH] gpio: max732x: Use irqchip template

[Sam Protsenko]

Hi Linus,

On Fri, 17 Jul 2020 at 17:19, Linus Walleij <linus.walleij@linaro.org> wrote:
>
> This makes the driver use the irqchip template to assign
> properties to the gpio_irq_chip instead of using the
> explicit calls to gpiochip_irqchip_add_nested() and
> gpiochip_set_nested_irqchip(). The irqchip is instead
> added while adding the gpiochip.
>
> Cc: Sam Protsenko <semen.protsenko@linaro.org>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---

I can test it on my MAX7325 board with BeagleBone Black in a day or
two. Do you want me to verify your patch on top of linux-mainline or
linux-next? Also, is there any specific stuff you want me to look at,
or making sure there are no regressions w.r.t. IRQ from the chip is
enough?

Thanks!

>  drivers/gpio/gpio-max732x.c | 26 +++++++++++++-------------
>  1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
> index 63472f308857..347415344a20 100644
> --- a/drivers/gpio/gpio-max732x.c
> +++ b/drivers/gpio/gpio-max732x.c
> @@ -503,6 +503,8 @@ static int max732x_irq_setup(struct max732x_chip *chip,
>
>         if (((pdata && pdata->irq_base) || client->irq)
>                         && has_irq != INT_NONE) {
> +               struct gpio_irq_chip *girq;
> +
>                 if (pdata)
>                         irq_base = pdata->irq_base;
>                 chip->irq_features = has_irq;
> @@ -517,19 +519,17 @@ static int max732x_irq_setup(struct max732x_chip *chip,
>                                 client->irq);
>                         return ret;
>                 }
> -               ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
> -                                                  &max732x_irq_chip,
> -                                                  irq_base,
> -                                                  handle_simple_irq,
> -                                                  IRQ_TYPE_NONE);
> -               if (ret) {
> -                       dev_err(&client->dev,
> -                               "could not connect irqchip to gpiochip\n");
> -                       return ret;
> -               }
> -               gpiochip_set_nested_irqchip(&chip->gpio_chip,
> -                                           &max732x_irq_chip,
> -                                           client->irq);
> +
> +               girq = &chip->gpio_chip.irq;
> +               girq->chip = &max732x_irq_chip;
> +               /* This will let us handle the parent IRQ in the driver */
> +               girq->parent_handler = NULL;
> +               girq->num_parents = 0;
> +               girq->parents = NULL;
> +               girq->default_type = IRQ_TYPE_NONE;
> +               girq->handler = handle_simple_irq;
> +               girq->threaded = true;
> +               girq->first = irq_base; /* FIXME: get rid of this */
>         }
>
>         return 0;
> --
> 2.26.2
>

Re: [PATCH] gpio: max732x: Use irqchip template

[Linus Walleij]

On Sun, Jul 19, 2020 at 6:34 PM Sam Protsenko
<semen.protsenko@linaro.org> wrote:
> On Fri, 17 Jul 2020 at 17:19, Linus Walleij <linus.walleij@linaro.org> wrote:
> >
> > This makes the driver use the irqchip template to assign
> > properties to the gpio_irq_chip instead of using the
> > explicit calls to gpiochip_irqchip_add_nested() and
> > gpiochip_set_nested_irqchip(). The irqchip is instead
> > added while adding the gpiochip.
> >
> > Cc: Sam Protsenko <semen.protsenko@linaro.org>
> > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

> I can test it on my MAX7325 board with BeagleBone Black in a day or
> two.

Thanks! No hurry.

> Do you want me to verify your patch on top of linux-mainline or
> linux-next?

Either should work.

> Also, is there any specific stuff you want me to look at,
> or making sure there are no regressions w.r.t. IRQ from the chip is
> enough?

Just that really, that the IRQs happen as before.

Yours,
Linus Walleij

Re: [PATCH] gpio: max732x: Use irqchip template

[Sam Protsenko]

Hi Linus,

On Tue, 21 Jul 2020 at 12:54, Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Sun, Jul 19, 2020 at 6:34 PM Sam Protsenko
> <semen.protsenko@linaro.org> wrote:
> > On Fri, 17 Jul 2020 at 17:19, Linus Walleij <linus.walleij@linaro.org> wrote:
> > >
> > > This makes the driver use the irqchip template to assign
> > > properties to the gpio_irq_chip instead of using the
> > > explicit calls to gpiochip_irqchip_add_nested() and
> > > gpiochip_set_nested_irqchip(). The irqchip is instead
> > > added while adding the gpiochip.
> > >
> > > Cc: Sam Protsenko <semen.protsenko@linaro.org>
> > > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
>
> > I can test it on my MAX7325 board with BeagleBone Black in a day or
> > two.
>
> Thanks! No hurry.
>
> > Do you want me to verify your patch on top of linux-mainline or
> > linux-next?
>
> Either should work.
>
> > Also, is there any specific stuff you want me to look at,
> > or making sure there are no regressions w.r.t. IRQ from the chip is
> > enough?
>
> Just that really, that the IRQs happen as before.
>

Just tested it on my MAX7325 board [1], by adding gpio-keys and
gpio-leds to BBB dts [2]. Alas, the patch seems to be breaking IRQs.
Before the patch, I can see gpio-buttons appear in /proc/interrupts
and dmesg is clear of errors. After applying the patch, no gpio-keys
appear in /proc/interrupts and dmesg is reporting errors like this:

    irq: no irq domain found for max7325@68 !

This is probably because the patch is setting gpio_chip structure
fields after devm_gpiochip_add_data() was executed. Next hacky change
fixes it:

<<<<<<<<<<<<<<<<<< cut here >>>>>>>>>>>>>>>>>
@@ -695,11 +695,11 @@ static int max732x_probe(struct i2c_client *client,
                        return ret;
        }

-       ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
+       ret = max732x_irq_setup(chip, id);
        if (ret)
                return ret;

-       ret = max732x_irq_setup(chip, id);
+       ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
        if (ret)
                return ret;
 <<<<<<<<<<<<<<<<<< cut here >>>>>>>>>>>>>>>>>

I didn't check if it's a correct fix, so the diff above is only to
check the idea. Anyway, if you send v2 I can retest it, as my setup is
ready.

Thanks!

[1] https://github.com/joe-skb7/max7325-pcb
[2] https://github.com/joe-skb7/linux-mainline-bbb-max732x/commits/max732_bbb_test

> Yours,
> Linus Walleij

Re: [PATCH] gpio: max732x: Use irqchip template

[Andy Shevchenko]

On Fri, Jul 24, 2020 at 1:50 PM Sam Protsenko
<semen.protsenko@linaro.org> wrote:
> On Tue, 21 Jul 2020 at 12:54, Linus Walleij <linus.walleij@linaro.org> wrote:
> > On Sun, Jul 19, 2020 at 6:34 PM Sam Protsenko
> > <semen.protsenko@linaro.org> wrote:

...

> > Just that really, that the IRQs happen as before.

> Just tested it on my MAX7325 board [1], by adding gpio-keys and
> gpio-leds to BBB dts [2]. Alas, the patch seems to be breaking IRQs.
> Before the patch, I can see gpio-buttons appear in /proc/interrupts
> and dmesg is clear of errors. After applying the patch, no gpio-keys
> appear in /proc/interrupts and dmesg is reporting errors like this:
>
>     irq: no irq domain found for max7325@68 !
>
> This is probably because the patch is setting gpio_chip structure
> fields after devm_gpiochip_add_data() was executed.

...

> I didn't check if it's a correct fix, so the diff above is only to
> check the idea.

I checked pca953x and there the same trick has been applied. In my
setup that driver works. I think it's the right way to go.

-- 
With Best Regards,
Andy Shevchenko