RE: [PATCH] pinctrl: renesas: rzg2l: Configure interrupt input mode

[Biju Das <biju.das.jz@xxxxxxxxxxxxxx>]

Hi Geert,

Thanks for the feedback.

> Subject: Re: [PATCH] pinctrl: renesas: rzg2l: Configure interrupt input
> mode
> 
> Hi Biju,
> 
> On Fri, Oct 6, 2023 at 2:18 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > Configure GPIO interrupt as input mode. Also if the bootloader sets
> > gpio interrupt pin as function, override it as gpio.
> >
> > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> 
> Thanks for your patch!
> 
> > --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > @@ -1580,6 +1580,26 @@ static const struct irq_chip rzg2l_gpio_irqchip =
> {
> >         GPIOCHIP_IRQ_RESOURCE_HELPERS,  };
> >
> > +static int rzg2l_gpio_interrupt_input_mode(struct gpio_chip *chip,
> > +unsigned int offset) {
> > +       struct rzg2l_pinctrl *pctrl = gpiochip_get_data(chip);
> > +       const struct pinctrl_pin_desc *pin_desc = &pctrl-
> >desc.pins[offset];
> > +       u32 *pin_data = pin_desc->drv_data;
> > +       u32 off = RZG2L_PIN_CFG_TO_PORT_OFFSET(*pin_data);
> > +       u8 bit = RZG2L_PIN_ID_TO_PIN(offset);
> > +       u8 reg8;
> > +       int ret;
> > +
> > +       reg8 = readb(pctrl->base + PMC(off));
> > +       if (reg8 & BIT(bit)) {
> > +               ret = rzg2l_gpio_request(chip, offset);
> 
> Who is taking care of calling pinctrl_gpio_free() when the interrupt has
> been freed?

At the moment no, maybe we can use of rzg2l_gpio_irq_domain_free() to call pinctrl_gpio_free(),
Similar to freeing bitmap region??

> 
> > +               if (ret)
> > +                       return ret;
> > +       }
> > +
> > +       return rzg2l_gpio_direction_input(chip, offset); }
> > +
> >  static int rzg2l_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
> >                                             unsigned int child,
> >                                             unsigned int child_type,
> > @@ -1589,11 +1609,16 @@ static int
> rzg2l_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
> >         struct rzg2l_pinctrl *pctrl = gpiochip_get_data(gc);
> >         unsigned long flags;
> >         int gpioint, irq;
> > +       int ret;
> >
> >         gpioint = rzg2l_gpio_get_gpioint(child, pctrl->data);
> >         if (gpioint < 0)
> >                 return gpioint;
> >
> > +       ret = rzg2l_gpio_interrupt_input_mode(gc, child);
> > +       if (ret)
> > +               return ret;
> > +
> >         spin_lock_irqsave(&pctrl->bitmap_lock, flags);
> >         irq = bitmap_find_free_region(pctrl->tint_slot,
> RZG2L_TINT_MAX_INTERRUPT, get_order(1));
> >         spin_unlock_irqrestore(&pctrl->bitmap_lock, flags);
> 
> TBH, it's not very clear to me how this is used...
> I assume this is called as girq->child_to_parent_hwirq() from
> gpiochip_hierarchy_irq_domain_alloc()?
> Is that done from request_irq(), or at interrupt controller initialization
> time?

Basically during i2c_device_probe(). See the stack trace.

[    8.371896]  rzg2l_gpio_child_to_parent_hwirq+0xc4/0x1b8
[    8.377882]  gpiochip_hierarchy_irq_domain_alloc+0x90/0x1a4
[    8.384156]  irq_domain_alloc_irqs_locked+0xfc/0x354
[    8.389791]  irq_create_fwspec_mapping+0x208/0x350
[    8.395217]  irq_create_of_mapping+0x68/0x8c
[    8.400087]  of_irq_get+0x88/0xcc
[    8.403881]  i2c_device_probe+0x270/0x284

Cheers,
Biju