Re: [PATCH 5/5] pinctrl: sunxi: a523: add missing IRQ bank (plus old DT workaround)

[Chen-Yu Tsai]

On Mon, Mar 23, 2026 at 7:02 PM Andre Przywara <andre.przywara@xxxxxxx> wrote:
>
> The Allwinner A532 SoC implements 10 GPIO banks, each of which is
> interrupt capable. However the first bank (PortA) is skipped, so the
> indicies of those banks range from 1 to 10, not 0 to 9.
> We described the skipped bank correctly, but missed that for the IRQ
> banks, where we rely on the IRQ bank index to be aligned with the MMIO
> register offset, starting at 0x200.
>
> Correct that by increasing the number of IRQ banks to 11, to cover both
> the first skipped one, but also the last one (PortK). This fixes a bug
> where the interrupt numbers would be off-by-one, due to that
> mis-enumeration.
> The big caveat is that now old DTs break the kernel, since they only
> provide 10 interrupts, and the driver bails out entirely due to the last
> missing one. So add a workaround for this particular case, where we
> detect the requirement for 11 banks, but only 10 interrupts provided,
> and continue with 10 IRQs, albeit emitting a warning about a DT update.
> This would still be broken in terms of interrupt assignment, but it was
> broken the whole time before, so it's not a regression.
>
> Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
> ---
>  drivers/pinctrl/sunxi/pinctrl-sun55i-a523.c |  2 +-
>  drivers/pinctrl/sunxi/pinctrl-sunxi.c       | 22 +++++++++++++--------
>  2 files changed, 15 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/pinctrl/sunxi/pinctrl-sun55i-a523.c b/drivers/pinctrl/sunxi/pinctrl-sun55i-a523.c
> index b6f78f1f30ac..a1d157de53d2 100644
> --- a/drivers/pinctrl/sunxi/pinctrl-sun55i-a523.c
> +++ b/drivers/pinctrl/sunxi/pinctrl-sun55i-a523.c
> @@ -17,7 +17,7 @@ static const u8 a523_nr_bank_pins[SUNXI_PINCTRL_MAX_BANKS] =
>  /*       PA  PB  PC  PD  PE  PF  PG  PH  PI  PJ  PK */
>         {  0, 15, 17, 24, 16,  7, 15, 20, 17, 28, 24 };
>
> -static const unsigned int a523_irq_bank_map[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
> +static const unsigned int a523_irq_bank_map[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

Actually you don't even need this, since this is a linear mapping.

>From sunxi_irq_hw_bank_num():

    if (!desc->irq_bank_map)
            return bank;
    else
            return desc->irq_bank_map[bank];

>  static const u8 a523_irq_bank_muxes[SUNXI_PINCTRL_MAX_BANKS] =
>  /*       PA  PB  PC  PD  PE  PF  PG  PH  PI  PJ  PK */
> diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> index 6a86b7989b25..ffee79397590 100644
> --- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> +++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> @@ -19,6 +19,7 @@
>  #include <linux/irqdomain.h>
>  #include <linux/of.h>
>  #include <linux/of_clk.h>
> +#include <linux/of_irq.h>
>  #include <linux/platform_device.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/slab.h>
> @@ -1582,6 +1583,7 @@ int sunxi_pinctrl_init_with_flags(struct platform_device *pdev,
>         struct sunxi_pinctrl *pctl;
>         struct pinmux_ops *pmxops;
>         int i, ret, last_pin, pin_idx;
> +       int num_irq_banks;
>         struct clk *clk;
>
>         pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
> @@ -1715,16 +1717,20 @@ int sunxi_pinctrl_init_with_flags(struct platform_device *pdev,
>                 goto gpiochip_error;
>         }
>
> -       pctl->irq = devm_kcalloc(&pdev->dev,
> -                                pctl->desc->irq_banks,
> -                                sizeof(*pctl->irq),
> -                                GFP_KERNEL);
> +       num_irq_banks = pctl->desc->irq_banks;
> +       /* Workaround for old A523 DT, exposing one less interrupt. */
> +       if (num_irq_banks == 11 && of_irq_count(node) < 11) {
> +               num_irq_banks = 10;
> +               pr_warn("Not enough PIO interrupts, please update your DT!\n");
> +       }

I would probably make the check universal, and also use dev_warn().

    num_irq_banks = of_irq_count(node);
    if (num_irq_banks != pctrl->desc->irq_banks) {
        dev_warn(&pdev->dev, "Incorrect number of PIO interrupts,
please update your DT!\n");
        num_irq_banks = min(num_irq_banks, pctrl->desc->irq_banks);
    }

Otherwise,

Reviewed-by: Chen-Yu Tsai <wens@xxxxxxxxxx>


> +       pctl->irq = devm_kcalloc(&pdev->dev, num_irq_banks,
> +                                sizeof(*pctl->irq), GFP_KERNEL);
>         if (!pctl->irq) {
>                 ret = -ENOMEM;
>                 goto gpiochip_error;
>         }
>
> -       for (i = 0; i < pctl->desc->irq_banks; i++) {
> +       for (i = 0; i < num_irq_banks; i++) {
>                 pctl->irq[i] = platform_get_irq(pdev, i);
>                 if (pctl->irq[i] < 0) {
>                         ret = pctl->irq[i];
> @@ -1733,7 +1739,7 @@ int sunxi_pinctrl_init_with_flags(struct platform_device *pdev,
>         }
>
>         pctl->domain = irq_domain_create_linear(dev_fwnode(&pdev->dev),
> -                                               pctl->desc->irq_banks * IRQ_PER_BANK,
> +                                               num_irq_banks * IRQ_PER_BANK,
>                                                 &sunxi_pinctrl_irq_domain_ops, pctl);
>         if (!pctl->domain) {
>                 dev_err(&pdev->dev, "Couldn't register IRQ domain\n");
> @@ -1741,7 +1747,7 @@ int sunxi_pinctrl_init_with_flags(struct platform_device *pdev,
>                 goto gpiochip_error;
>         }
>
> -       for (i = 0; i < (pctl->desc->irq_banks * IRQ_PER_BANK); i++) {
> +       for (i = 0; i < (num_irq_banks * IRQ_PER_BANK); i++) {
>                 int irqno = irq_create_mapping(pctl->domain, i);
>
>                 irq_set_lockdep_class(irqno, &sunxi_pinctrl_irq_lock_class,
> @@ -1751,7 +1757,7 @@ int sunxi_pinctrl_init_with_flags(struct platform_device *pdev,
>                 irq_set_chip_data(irqno, pctl);
>         }
>
> -       for (i = 0; i < pctl->desc->irq_banks; i++) {
> +       for (i = 0; i < num_irq_banks; i++) {
>                 /* Mask and clear all IRQs before registering a handler */
>                 writel(0, pctl->membase +
>                           sunxi_irq_ctrl_reg_from_bank(pctl->desc, i));
> --
> 2.43.0
>
>