[PATCH] pinctrl: keembay: make keembay_gpio_irqchip const

[Areeb Ul Haq Mirza <auhmirza02@gmail.com>]

gpiolib warns about mutable irq_chips at probe time:
"not an immutable chip, please consider fixing it!"

Make keembay_gpio_irqchip const, flag it as IRQCHIP_IMMUTABLE, add the
GPIOCHIP_IRQ_RESOURCE_HELPERS and register it with
gpio_irq_chip_set_chip().

The chip only implements .irq_enable() and .irq_disable(), so call
gpiochip_enable_irq() and gpiochip_disable_irq() from those callbacks,
following commit 35d008679a5a ("pinctrl: plgpio: Convert to immutable
irq_chip") [1] and commit 2993d2dd8ff4 ("gpio: timberdale: Make irq_chip
immutable") [2]. gpiochip_enable_irq() is called once a free interrupt
source and slot have been found, so a line is only marked enabled when
it is actually routed. gpiochip_disable_irq() is called after the line
has been cleared from the interrupt configuration register.

Link: https://lore.kernel.org/r/20230414-immutable-irqchips-2-v1-3-6b59a5186b00@linaro.org [1]
Link: https://lore.kernel.org/r/20250509-gpio-v1-8-639377c98288@nxp.com [2]
Signed-off-by: Areeb Ul Haq Mirza <auhmirza02@gmail.com>
---
Compile-tested only (arm64, W=1, sparse).

 drivers/pinctrl/pinctrl-keembay.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-keembay.c b/drivers/pinctrl/pinctrl-keembay.c
index 3241d3ae6219..486577458883 100644
--- a/drivers/pinctrl/pinctrl-keembay.c
+++ b/drivers/pinctrl/pinctrl-keembay.c
@@ -1380,6 +1380,8 @@ static void keembay_gpio_irq_enable(struct irq_data *data)
 	if (src < 0 || slot < 0)
 		return;
 
+	gpiochip_enable_irq(gc, pin);
+
 	if (trig & KEEMBAY_GPIO_SENSE_LOW)
 		keembay_gpio_invert(kpc, pin);
 
@@ -1412,6 +1414,7 @@ static void keembay_gpio_irq_disable(struct irq_data *data)
 		for_each_set_clump8(pos, clump, &reg, BITS_PER_TYPE(typeof(reg))) {
 			if ((clump & ~KEEMBAY_GPIO_IRQ_ENABLE) == pin) {
 				keembay_gpio_clear_irq(data, pos, src, pin);
+				gpiochip_disable_irq(gc, pin);
 				return;
 			}
 		}
@@ -1451,12 +1454,14 @@ static int keembay_gpio_add_pin_ranges(struct gpio_chip *chip)
 	return ret;
 }
 
-static struct irq_chip keembay_gpio_irqchip = {
+static const struct irq_chip keembay_gpio_irqchip = {
 	.name = "keembay-gpio",
 	.irq_enable = keembay_gpio_irq_enable,
 	.irq_disable = keembay_gpio_irq_disable,
 	.irq_set_type = keembay_gpio_irq_set_type,
 	.irq_ack = keembay_gpio_irq_ack,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
 static int keembay_gpiochip_probe(struct keembay_pinctrl *kpc,
@@ -1468,7 +1473,7 @@ static int keembay_gpiochip_probe(struct keembay_pinctrl *kpc,
 
 	/* Setup GPIO IRQ chip */
 	girq			= &kpc->chip.irq;
-	girq->chip		= &keembay_gpio_irqchip;
+	gpio_irq_chip_set_chip(girq, &keembay_gpio_irqchip);
 	girq->parent_handler	= keembay_gpio_irq_handler;
 	girq->num_parents	= KEEMBAY_GPIO_NUM_IRQ;
 	girq->parents		= devm_kcalloc(kpc->dev, girq->num_parents,

base-commit: f33a24cc012d34f25bb9942681bd478a1757b806
-- 
2.53.0