Re: [PATCH v2] gpio: sifive: Make the irqchip immutable

[Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>]

On 5/20/22 19:24, Geert Uytterhoeven wrote:
> Commit 6c846d026d49 ("gpio: Don't fiddle with irqchips marked as
> immutable") added a warning to indicate if the gpiolib is altering the
> internals of irqchips.  Following this change the following warning is
> now observed for the sifive driver:
> 
>     gpio gpiochip1: (38001000.gpio-controller): not an immutable chip, please consider fixing it!
> 
> Fix this by making the irqchip in the sifive driver immutable.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> Against gpio/for-next.
> Boot-tested on SiPEED MAiXBiT (Canaan K210).
> 
> v2:
>   - Factor out hwirq using preferred helper.
> ---
>  drivers/gpio/gpio-sifive.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
> index 03b8c4de2e91e3c4..238f3210970cfa0e 100644
> --- a/drivers/gpio/gpio-sifive.c
> +++ b/drivers/gpio/gpio-sifive.c
> @@ -75,10 +75,12 @@ static void sifive_gpio_irq_enable(struct irq_data *d)
>  {
>  	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
>  	struct sifive_gpio *chip = gpiochip_get_data(gc);
> -	int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
> +	irq_hw_number_t hwirq = irqd_to_hwirq(d);
> +	int offset = hwirq % SIFIVE_GPIO_MAX;
>  	u32 bit = BIT(offset);
>  	unsigned long flags;
>  
> +	gpiochip_enable_irq(gc, hwirq);
>  	irq_chip_enable_parent(d);
>  
>  	/* Switch to input */
> @@ -101,11 +103,13 @@ static void sifive_gpio_irq_disable(struct irq_data *d)
>  {
>  	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
>  	struct sifive_gpio *chip = gpiochip_get_data(gc);
> -	int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
> +	irq_hw_number_t hwirq = irqd_to_hwirq(d);
> +	int offset = hwirq % SIFIVE_GPIO_MAX;
>  
>  	assign_bit(offset, &chip->irq_state, 0);
>  	sifive_gpio_set_ie(chip, offset);
>  	irq_chip_disable_parent(d);
> +	gpiochip_disable_irq(gc, hwirq);
>  }
>  
>  static void sifive_gpio_irq_eoi(struct irq_data *d)
> @@ -137,7 +141,7 @@ static int sifive_gpio_irq_set_affinity(struct irq_data *data,
>  	return -EINVAL;
>  }
>  
> -static struct irq_chip sifive_gpio_irqchip = {
> +static const struct irq_chip sifive_gpio_irqchip = {
>  	.name		= "sifive-gpio",
>  	.irq_set_type	= sifive_gpio_irq_set_type,
>  	.irq_mask	= irq_chip_mask_parent,
> @@ -146,6 +150,8 @@ static struct irq_chip sifive_gpio_irqchip = {
>  	.irq_disable	= sifive_gpio_irq_disable,
>  	.irq_eoi	= sifive_gpio_irq_eoi,
>  	.irq_set_affinity = sifive_gpio_irq_set_affinity,
> +	.flags		= IRQCHIP_IMMUTABLE,
> +	GPIOCHIP_IRQ_RESOURCE_HELPERS,
>  };
>  
>  static int sifive_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
> @@ -242,7 +248,7 @@ static int sifive_gpio_probe(struct platform_device *pdev)
>  	chip->gc.parent = dev;
>  	chip->gc.owner = THIS_MODULE;
>  	girq = &chip->gc.irq;
> -	girq->chip = &sifive_gpio_irqchip;
> +	gpio_irq_chip_set_chip(girq, &sifive_gpio_irqchip);
>  	girq->fwnode = of_node_to_fwnode(node);
>  	girq->parent_domain = parent;
>  	girq->child_to_parent_hwirq = sifive_gpio_child_to_parent_hwirq;

Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>

-- 
Damien Le Moal
Western Digital Research