ath79: backport gpio immutable irq_chip support

This patch converts the driver to immutable irq-chip, which can
silence some gpio warnings.

Signed-off-by: Shiji Yang <[email protected]>

target/linux/ath79/patches-6.1/010-v6.4-gpio-ath79-Convert-to-immutable-irq_chip.patch

@@ -0,0 +1,60 @@
+From b11ce7e48121a02ceedec9f4dfcab4f2bee8f35f Mon Sep 17 00:00:00 2001
+From: Linus Walleij <[email protected]>
+Date: Thu, 9 Mar 2023 08:45:54 +0100
+Subject: gpio: ath79: Convert to immutable irq_chip
+
+Convert the driver to immutable irq-chip with a bit of
+intuition.
+
+Cc: Marc Zyngier <[email protected]>
+Acked-by: Marc Zyngier <[email protected]>
+Signed-off-by: Linus Walleij <[email protected]>
+Signed-off-by: Bartosz Golaszewski <[email protected]>
+---
+ drivers/gpio/gpio-ath79.c | 8 ++++++--
+ 1 file changed, 6 insertions(+), 2 deletions(-)
+
+--- a/drivers/gpio/gpio-ath79.c
++++ b/drivers/gpio/gpio-ath79.c
+@@ -71,6 +71,7 @@ static void ath79_gpio_irq_unmask(struct
+ 	u32 mask = BIT(irqd_to_hwirq(data));
+ 	unsigned long flags;
+ 
++	gpiochip_enable_irq(&ctrl->gc, irqd_to_hwirq(data));
+ 	raw_spin_lock_irqsave(&ctrl->lock, flags);
+ 	ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask);
+ 	raw_spin_unlock_irqrestore(&ctrl->lock, flags);
+@@ -85,6 +86,7 @@ static void ath79_gpio_irq_mask(struct i
+ 	raw_spin_lock_irqsave(&ctrl->lock, flags);
+ 	ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0);
+ 	raw_spin_unlock_irqrestore(&ctrl->lock, flags);
++	gpiochip_disable_irq(&ctrl->gc, irqd_to_hwirq(data));
+ }
+ 
+ static void ath79_gpio_irq_enable(struct irq_data *data)
+@@ -169,13 +171,15 @@ static int ath79_gpio_irq_set_type(struc
+ 	return 0;
+ }
+ 
+-static struct irq_chip ath79_gpio_irqchip = {
++static const struct irq_chip ath79_gpio_irqchip = {
+ 	.name = "gpio-ath79",
+ 	.irq_enable = ath79_gpio_irq_enable,
+ 	.irq_disable = ath79_gpio_irq_disable,
+ 	.irq_mask = ath79_gpio_irq_mask,
+ 	.irq_unmask = ath79_gpio_irq_unmask,
+ 	.irq_set_type = ath79_gpio_irq_set_type,
++	.flags = IRQCHIP_IMMUTABLE,
++	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+ };
+ 
+ static void ath79_gpio_irq_handler(struct irq_desc *desc)
+@@ -274,7 +278,7 @@ static int ath79_gpio_probe(struct platf
+ 	/* Optional interrupt setup */
+ 	if (!np || of_property_read_bool(np, "interrupt-controller")) {
+ 		girq = &ctrl->gc.irq;
+-		girq->chip = &ath79_gpio_irqchip;
++		gpio_irq_chip_set_chip(girq, &ath79_gpio_irqchip);
+ 		girq->parent_handler = ath79_gpio_irq_handler;
+ 		girq->num_parents = 1;
+ 		girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),