[v8,4/6] gpio: gpiolib: Allow free() callback to be overridden

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Allow free() callback to be overridden from irq_domain_ops for
hierarchical chips.

This allows drivers to free up resources which are allocated during
child_to_parent_hwirq()/populate_parent_alloc_arg() callbacks.

On Renesas RZ/G2L platform a bitmap is maintained for TINT slots, a slot
is allocated in child_to_parent_hwirq() callback which is freed up in free
callback hence this override.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/gpio/gpiolib.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

On Thu, Jul 7, 2022 at 8:24 PM <prabhakar.csengg@gmail.com> wrote:
>
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Allow free() callback to be overridden from irq_domain_ops for
> hierarchical chips.
>
> This allows drivers to free up resources which are allocated during
> child_to_parent_hwirq()/populate_parent_alloc_arg() callbacks.
>
> On Renesas RZ/G2L platform a bitmap is maintained for TINT slots, a slot
> is allocated in child_to_parent_hwirq() callback which is freed up in free
> callback hence this override.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/gpio/gpiolib.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index bfde94243752..68d9f95d7799 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1181,15 +1181,18 @@ static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
>         ops->activate = gpiochip_irq_domain_activate;
>         ops->deactivate = gpiochip_irq_domain_deactivate;
>         ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
> -       ops->free = irq_domain_free_irqs_common;
>
>         /*
> -        * We only allow overriding the translate() function for
> +        * We only allow overriding the translate() and free() functions for
>          * hierarchical chips, and this should only be done if the user
> -        * really need something other than 1:1 translation.
> +        * really need something other than 1:1 translation for translate()
> +        * callback and free if user wants to free up any resources which
> +        * were allocated during callbacks, for example populate_parent_alloc_arg.
>          */
>         if (!ops->translate)
>                 ops->translate = gpiochip_hierarchy_irq_domain_translate;
> +       if (!ops->free)
> +               ops->free = irq_domain_free_irqs_common;
>  }
>
>  static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
> --
> 2.25.1
>

Acked-by: Bartosz Golaszewski <brgl@bgdev.pl>

Which tree is this targetting?

On Fri, 08 Jul 2022 16:52:21 +0100,
Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> 
> On Thu, Jul 7, 2022 at 8:24 PM <prabhakar.csengg@gmail.com> wrote:
> >
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Allow free() callback to be overridden from irq_domain_ops for
> > hierarchical chips.
> >
> > This allows drivers to free up resources which are allocated during
> > child_to_parent_hwirq()/populate_parent_alloc_arg() callbacks.
> >
> > On Renesas RZ/G2L platform a bitmap is maintained for TINT slots, a slot
> > is allocated in child_to_parent_hwirq() callback which is freed up in free
> > callback hence this override.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> >  drivers/gpio/gpiolib.c | 9 ++++++---
> >  1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index bfde94243752..68d9f95d7799 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -1181,15 +1181,18 @@ static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
> >         ops->activate = gpiochip_irq_domain_activate;
> >         ops->deactivate = gpiochip_irq_domain_deactivate;
> >         ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
> > -       ops->free = irq_domain_free_irqs_common;
> >
> >         /*
> > -        * We only allow overriding the translate() function for
> > +        * We only allow overriding the translate() and free() functions for
> >          * hierarchical chips, and this should only be done if the user
> > -        * really need something other than 1:1 translation.
> > +        * really need something other than 1:1 translation for translate()
> > +        * callback and free if user wants to free up any resources which
> > +        * were allocated during callbacks, for example populate_parent_alloc_arg.
> >          */
> >         if (!ops->translate)
> >                 ops->translate = gpiochip_hierarchy_irq_domain_translate;
> > +       if (!ops->free)
> > +               ops->free = irq_domain_free_irqs_common;
> >  }
> >
> >  static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
> > --
> > 2.25.1
> >
> 
> Acked-by: Bartosz Golaszewski <brgl@bgdev.pl>
> 
> Which tree is this targetting?
> 

Given the various dependencies, I've created a stable branch[1] on top
of -rc3, and merged the whole thing into irq/irqchip-next.

Feel free to pull the branch in the GPIO tree as well.

Thanks,

	M.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=irq/renesas-irqc