gpio: zynq: fix zynqmp_gpio not an immutable chip warning

Make the struct irq_chip const and flag it as IRQCHIP_IMMUTABLE,
call gpiochip_disable_irq() in the .irq_mask() callback and
gpiochip_enable_irq() in the .irq_unmask() callback to fix
"gpio gpiochip1: (zynqmp_gpio): not an immutable chip" warning.

Signed-off-by: Manikanta Guntupalli <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-zynq.c

···
 	int bank_max[ZYNQMP_GPIO_MAX_BANK];
 };
 
-static struct irq_chip zynq_gpio_level_irqchip;
-static struct irq_chip zynq_gpio_edge_irqchip;
+static const struct irq_chip zynq_gpio_level_irqchip;
+static const struct irq_chip zynq_gpio_edge_irqchip;
 
 /**
  * zynq_gpio_is_zynq - test if HW is zynq or zynqmp
···
 static void zynq_gpio_irq_mask(struct irq_data *irq_data)
 {
 	unsigned int device_pin_num, bank_num, bank_pin_num;
+	const unsigned long offset = irqd_to_hwirq(irq_data);
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(irq_data);
 	struct zynq_gpio *gpio =
 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
 
+	gpiochip_disable_irq(chip, offset);
 	device_pin_num = irq_data->hwirq;
 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
 	writel_relaxed(BIT(bank_pin_num),
···
 static void zynq_gpio_irq_unmask(struct irq_data *irq_data)
 {
 	unsigned int device_pin_num, bank_num, bank_pin_num;
+	const unsigned long offset = irqd_to_hwirq(irq_data);
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(irq_data);
 	struct zynq_gpio *gpio =
 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
 
+	gpiochip_enable_irq(chip, offset);
 	device_pin_num = irq_data->hwirq;
 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
 	writel_relaxed(BIT(bank_pin_num),
···
 }
 
 /* irq chip descriptor */
-static struct irq_chip zynq_gpio_level_irqchip = {
+static const struct irq_chip zynq_gpio_level_irqchip = {
 	.name		= DRIVER_NAME,
 	.irq_enable	= zynq_gpio_irq_enable,
 	.irq_eoi	= zynq_gpio_irq_ack,
···
 	.irq_request_resources = zynq_gpio_irq_reqres,
 	.irq_release_resources = zynq_gpio_irq_relres,
 	.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED |
-			  IRQCHIP_MASK_ON_SUSPEND,
+			  IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
-static struct irq_chip zynq_gpio_edge_irqchip = {
+static const struct irq_chip zynq_gpio_edge_irqchip = {
 	.name		= DRIVER_NAME,
 	.irq_enable	= zynq_gpio_irq_enable,
 	.irq_ack	= zynq_gpio_irq_ack,
···
 	.irq_set_wake	= zynq_gpio_set_wake,
 	.irq_request_resources = zynq_gpio_irq_reqres,
 	.irq_release_resources = zynq_gpio_irq_relres,
-	.flags		= IRQCHIP_MASK_ON_SUSPEND,
+	.flags		= IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
 static void zynq_gpio_handle_bank_irq(struct zynq_gpio *gpio,
···
 
 	/* Set up the GPIO irqchip */
 	girq = &chip->irq;
-	girq->chip = &zynq_gpio_edge_irqchip;
+	gpio_irq_chip_set_chip(girq, &zynq_gpio_edge_irqchip);
 	girq->parent_handler = zynq_gpio_irqhandler;
 	girq->num_parents = 1;
 	girq->parents = devm_kcalloc(&pdev->dev, 1,