diff mbox series

[v3,4/5] gpio: gpiolib: Add ngirq member to struct gpio_irq_chip

Message ID 20220511183210.5248-5-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive)
State Superseded
Delegated to: Geert Uytterhoeven
Headers show
Series Renesas RZ/G2L IRQC support | expand

Commit Message

Prabhakar May 11, 2022, 6:32 p.m. UTC
Supported GPIO IRQs by the chip is not always equal to the number of GPIO
pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
a give point a maximum of only 32 GPIO pins can be used as IRQ lines in
the IRQC domain.

This patch adds ngirq member to struct gpio_irq_chip and passes this as a
size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
being set in the driver otherwise fallbacks to using ngpio.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 drivers/gpio/gpiolib.c      | 4 ++--
 include/linux/gpio/driver.h | 8 ++++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

Comments

Geert Uytterhoeven May 12, 2022, 7:29 a.m. UTC | #1
Hi Prabhakar,

On Wed, May 11, 2022 at 8:32 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> Supported GPIO IRQs by the chip is not always equal to the number of GPIO
> pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
> a give point a maximum of only 32 GPIO pins can be used as IRQ lines in
> the IRQC domain.
>
> This patch adds ngirq member to struct gpio_irq_chip and passes this as a
> size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
> being set in the driver otherwise fallbacks to using ngpio.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1221,7 +1221,7 @@ static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
>         gc->irq.domain = irq_domain_create_hierarchy(
>                 gc->irq.parent_domain,
>                 0,
> -               gc->ngpio,
> +               gc->irq.ngirq ?: gc->ngpio,
>                 gc->irq.fwnode,
>                 &gc->irq.child_irq_domain_ops,
>                 gc);
> @@ -1574,7 +1574,7 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc,
>         } else {
>                 /* Some drivers provide custom irqdomain ops */
>                 gc->irq.domain = irq_domain_create_simple(fwnode,
> -                       gc->ngpio,
> +                       gc->irq.ngirq ?: gc->ngpio,
>                         gc->irq.first,
>                         gc->irq.domain_ops ?: &gpiochip_domain_ops,
>                         gc);

OK.

gpiochip_irqchip_remove() does:

        /* Remove all IRQ mappings and delete the domain */
        if (gc->irq.domain) {
                unsigned int irq;

                for (offset = 0; offset < gc->ngpio; offset++) {
                       if (!gpiochip_irqchip_irq_valid(gc, offset))

Hence it relies on gc->irq.valid_mask, which I think is OK in general.

                                continue;

                        irq = irq_find_mapping(gc->irq.domain, offset);
                        irq_dispose_mapping(irq);
                }

                irq_domain_remove(gc->irq.domain);

        }

> --- a/include/linux/gpio/driver.h
> +++ b/include/linux/gpio/driver.h
> @@ -51,6 +51,14 @@ struct gpio_irq_chip {
>          */
>         const struct irq_domain_ops *domain_ops;
>
> +       /**
> +        * @ngirq:
> +        *
> +        * The number of GPIO IRQ's handled by this IRQ domain; usually is
> +        * equal to ngpio.

"If not set, ngpio will be used."

> +        */
> +       u16 ngirq;
> +
>  #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
>         /**
>          * @fwnode:

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
Linus Walleij May 13, 2022, 8:47 p.m. UTC | #2
On Wed, May 11, 2022 at 8:32 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:

> Supported GPIO IRQs by the chip is not always equal to the number of GPIO
> pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
> a give point a maximum of only 32 GPIO pins can be used as IRQ lines in
> the IRQC domain.
>
> This patch adds ngirq member to struct gpio_irq_chip and passes this as a
> size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
> being set in the driver otherwise fallbacks to using ngpio.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

As Geert says, I think you can just use .valid_mask for this,
what do you say?

Yours,
Linus Walleij
Lad, Prabhakar May 18, 2022, 6:30 p.m. UTC | #3
Hi Geert,

Thank you for the review.

On Thu, May 12, 2022 at 8:29 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Wed, May 11, 2022 at 8:32 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> > Supported GPIO IRQs by the chip is not always equal to the number of GPIO
> > pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
> > a give point a maximum of only 32 GPIO pins can be used as IRQ lines in
> > the IRQC domain.
> >
> > This patch adds ngirq member to struct gpio_irq_chip and passes this as a
> > size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
> > being set in the driver otherwise fallbacks to using ngpio.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Thanks for your patch!
>
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -1221,7 +1221,7 @@ static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
> >         gc->irq.domain = irq_domain_create_hierarchy(
> >                 gc->irq.parent_domain,
> >                 0,
> > -               gc->ngpio,
> > +               gc->irq.ngirq ?: gc->ngpio,
> >                 gc->irq.fwnode,
> >                 &gc->irq.child_irq_domain_ops,
> >                 gc);
> > @@ -1574,7 +1574,7 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc,
> >         } else {
> >                 /* Some drivers provide custom irqdomain ops */
> >                 gc->irq.domain = irq_domain_create_simple(fwnode,
> > -                       gc->ngpio,
> > +                       gc->irq.ngirq ?: gc->ngpio,
> >                         gc->irq.first,
> >                         gc->irq.domain_ops ?: &gpiochip_domain_ops,
> >                         gc);
>
> OK.
>
> gpiochip_irqchip_remove() does:
>
>         /* Remove all IRQ mappings and delete the domain */
>         if (gc->irq.domain) {
>                 unsigned int irq;
>
>                 for (offset = 0; offset < gc->ngpio; offset++) {
>                        if (!gpiochip_irqchip_irq_valid(gc, offset))
>
> Hence it relies on gc->irq.valid_mask, which I think is OK in general.
>
Agreed.

>                                 continue;
>
>                         irq = irq_find_mapping(gc->irq.domain, offset);
>                         irq_dispose_mapping(irq);
>                 }
>
>                 irq_domain_remove(gc->irq.domain);
>
>         }
>
> > --- a/include/linux/gpio/driver.h
> > +++ b/include/linux/gpio/driver.h
> > @@ -51,6 +51,14 @@ struct gpio_irq_chip {
> >          */
> >         const struct irq_domain_ops *domain_ops;
> >
> > +       /**
> > +        * @ngirq:
> > +        *
> > +        * The number of GPIO IRQ's handled by this IRQ domain; usually is
> > +        * equal to ngpio.
>
> "If not set, ngpio will be used."
>
sure will update the comment.

Cheers,
Prabhakar

> > +        */
> > +       u16 ngirq;
> > +
> >  #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
> >         /**
> >          * @fwnode:
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds
Lad, Prabhakar May 18, 2022, 6:36 p.m. UTC | #4
Hi Linus,

Thank you for the review.

On Fri, May 13, 2022 at 9:47 PM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Wed, May 11, 2022 at 8:32 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
>
> > Supported GPIO IRQs by the chip is not always equal to the number of GPIO
> > pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
> > a give point a maximum of only 32 GPIO pins can be used as IRQ lines in
> > the IRQC domain.
> >
> > This patch adds ngirq member to struct gpio_irq_chip and passes this as a
> > size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
> > being set in the driver otherwise fallbacks to using ngpio.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> As Geert says, I think you can just use .valid_mask for this,
> what do you say?
>
I don't think Geert is suggesting that. The .valid_mask option is one
time setting but what I need is something dynamic i.e. out of 392 GPIO
pins any 32 can be used as an interrupt pin. Also with this patch we
also save on memory [0].

[0] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/kernel/irq/irqdomain.c?h=next-20220518#n153

Cheers,
Prabhakar
Linus Walleij May 19, 2022, 1:21 p.m. UTC | #5
On Wed, May 18, 2022 at 8:36 PM Lad, Prabhakar
<prabhakar.csengg@gmail.com> wrote:

> > As Geert says, I think you can just use .valid_mask for this,
> > what do you say?
> >
> I don't think Geert is suggesting that. The .valid_mask option is one
> time setting but what I need is something dynamic i.e. out of 392 GPIO
> pins any 32 can be used as an interrupt pin.

So why can't this just be determined from the compatible?
This does not sound like a configuration option at all but something
related to the IP block per se, and then you know that if it has
a certain compatible then it has this property.

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d36c4a965efc..a98877f939ea 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1221,7 +1221,7 @@  static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
 	gc->irq.domain = irq_domain_create_hierarchy(
 		gc->irq.parent_domain,
 		0,
-		gc->ngpio,
+		gc->irq.ngirq ?: gc->ngpio,
 		gc->irq.fwnode,
 		&gc->irq.child_irq_domain_ops,
 		gc);
@@ -1574,7 +1574,7 @@  static int gpiochip_add_irqchip(struct gpio_chip *gc,
 	} else {
 		/* Some drivers provide custom irqdomain ops */
 		gc->irq.domain = irq_domain_create_simple(fwnode,
-			gc->ngpio,
+			gc->irq.ngirq ?: gc->ngpio,
 			gc->irq.first,
 			gc->irq.domain_ops ?: &gpiochip_domain_ops,
 			gc);
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 874aabd270c9..ed6df186907d 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -51,6 +51,14 @@  struct gpio_irq_chip {
 	 */
 	const struct irq_domain_ops *domain_ops;
 
+	/**
+	 * @ngirq:
+	 *
+	 * The number of GPIO IRQ's handled by this IRQ domain; usually is
+	 * equal to ngpio.
+	 */
+	u16 ngirq;
+
 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
 	/**
 	 * @fwnode: