gpio: vf610: make irq_chip immutable

Since recently, the kernel is nagging about mutable irq_chips:

    "not an immutable chip, please consider fixing it!"

Drop the unneeded copy, flag it as IRQCHIP_IMMUTABLE, add the new
helper functions and call the appropriate gpiolib functions.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-vf610.c

@@ -30,7 +30,6 @@ struct fsl_gpio_soc_data {
 
 struct vf610_gpio_port {
 	struct gpio_chip gc;
-	struct irq_chip ic;
 	void __iomem *base;
 	void __iomem *gpio_base;
 	const struct fsl_gpio_soc_data *sdata;
@@ -207,20 +206,24 @@ static int vf610_gpio_irq_set_type(struct irq_data *d, u32 type)
 
 static void vf610_gpio_irq_mask(struct irq_data *d)
 {
-	struct vf610_gpio_port *port =
-		gpiochip_get_data(irq_data_get_irq_chip_data(d));
-	void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct vf610_gpio_port *port = gpiochip_get_data(gc);
+	irq_hw_number_t gpio_num = irqd_to_hwirq(d);
+	void __iomem *pcr_base = port->base + PORT_PCR(gpio_num);
 
 	vf610_gpio_writel(0, pcr_base);
+	gpiochip_disable_irq(gc, gpio_num);
 }
 
 static void vf610_gpio_irq_unmask(struct irq_data *d)
 {
-	struct vf610_gpio_port *port =
-		gpiochip_get_data(irq_data_get_irq_chip_data(d));
-	void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct vf610_gpio_port *port = gpiochip_get_data(gc);
+	irq_hw_number_t gpio_num = irqd_to_hwirq(d);
+	void __iomem *pcr_base = port->base + PORT_PCR(gpio_num);
 
-	vf610_gpio_writel(port->irqc[d->hwirq] << PORT_PCR_IRQC_OFFSET,
+	gpiochip_enable_irq(gc, gpio_num);
+	vf610_gpio_writel(port->irqc[gpio_num] << PORT_PCR_IRQC_OFFSET,
 			  pcr_base);
 }
 
@@ -237,6 +240,17 @@ static int vf610_gpio_irq_set_wake(struct irq_data *d, u32 enable)
 	return 0;
 }
 
+static const struct irq_chip vf610_irqchip = {
+	.name = "gpio-vf610",
+	.irq_ack = vf610_gpio_irq_ack,
+	.irq_mask = vf610_gpio_irq_mask,
+	.irq_unmask = vf610_gpio_irq_unmask,
+	.irq_set_type = vf610_gpio_irq_set_type,
+	.irq_set_wake = vf610_gpio_irq_set_wake,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
 static void vf610_gpio_disable_clk(void *data)
 {
 	clk_disable_unprepare(data);
@@ -249,7 +263,6 @@ static int vf610_gpio_probe(struct platform_device *pdev)
 	struct vf610_gpio_port *port;
 	struct gpio_chip *gc;
 	struct gpio_irq_chip *girq;
-	struct irq_chip *ic;
 	int i;
 	int ret;
 
@@ -315,14 +328,6 @@ static int vf610_gpio_probe(struct platform_device *pdev)
 	gc->direction_output = vf610_gpio_direction_output;
 	gc->set = vf610_gpio_set;
 
-	ic = &port->ic;
-	ic->name = "gpio-vf610";
-	ic->irq_ack = vf610_gpio_irq_ack;
-	ic->irq_mask = vf610_gpio_irq_mask;
-	ic->irq_unmask = vf610_gpio_irq_unmask;
-	ic->irq_set_type = vf610_gpio_irq_set_type;
-	ic->irq_set_wake = vf610_gpio_irq_set_wake;
-
 	/* Mask all GPIO interrupts */
 	for (i = 0; i < gc->ngpio; i++)
 		vf610_gpio_writel(0, port->base + PORT_PCR(i));
@@ -331,7 +336,7 @@ static int vf610_gpio_probe(struct platform_device *pdev)
 	vf610_gpio_writel(~0, port->base + PORT_ISFR);
 
 	girq = &gc->irq;
-	girq->chip = ic;
+	gpio_irq_chip_set_chip(girq, &vf610_irqchip);
 	girq->parent_handler = vf610_gpio_irq_handler;
 	girq->num_parents = 1;
 	girq->parents = devm_kcalloc(&pdev->dev, 1,