gpio: ep93xx: Make irqchip immutable

This turns the Cirrus ep93xx gpio irqchip immutable.

Preserve per-chip labels by adding an ->irq_print_chip() callback.
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-ep93xx.c

@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/gpio/driver.h>
 #include <linux/bitops.h>
+#include <linux/seq_file.h>
 
 #define EP93XX_GPIO_F_INT_STATUS 0x5c
 #define EP93XX_GPIO_A_INT_STATUS 0xa0
@@ -40,7 +41,6 @@
 #define EP93XX_GPIO_F_IRQ_BASE 80
 
 struct ep93xx_gpio_irq_chip {
-	struct irq_chip ic;
 	u8 irq_offset;
 	u8 int_unmasked;
 	u8 int_enabled;
@@ -185,6 +185,7 @@ static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
 	ep93xx_gpio_update_int_params(epg, eic);
 
 	writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
+	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
 }
 
 static void ep93xx_gpio_irq_mask(struct irq_data *d)
@@ -195,6 +196,7 @@ static void ep93xx_gpio_irq_mask(struct irq_data *d)
 
 	eic->int_unmasked &= ~BIT(d->irq & 7);
 	ep93xx_gpio_update_int_params(epg, eic);
+	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
 }
 
 static void ep93xx_gpio_irq_unmask(struct irq_data *d)
@@ -203,6 +205,7 @@ static void ep93xx_gpio_irq_unmask(struct irq_data *d)
 	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
 	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
 
+	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
 	eic->int_unmasked |= BIT(d->irq & 7);
 	ep93xx_gpio_update_int_params(epg, eic);
 }
@@ -320,15 +323,25 @@ static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset,
 	return 0;
 }
 
-static void ep93xx_init_irq_chip(struct device *dev, struct irq_chip *ic)
+static void ep93xx_irq_print_chip(struct irq_data *data, struct seq_file *p)
 {
-	ic->irq_ack = ep93xx_gpio_irq_ack;
-	ic->irq_mask_ack = ep93xx_gpio_irq_mask_ack;
-	ic->irq_mask = ep93xx_gpio_irq_mask;
-	ic->irq_unmask = ep93xx_gpio_irq_unmask;
-	ic->irq_set_type = ep93xx_gpio_irq_type;
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+
+	seq_printf(p, dev_name(gc->parent));
 }
 
+static const struct irq_chip gpio_eic_irq_chip = {
+	.name			= "ep93xx-gpio-eic",
+	.irq_ack		= ep93xx_gpio_irq_ack,
+	.irq_mask		= ep93xx_gpio_irq_mask,
+	.irq_unmask		= ep93xx_gpio_irq_unmask,
+	.irq_mask_ack	= ep93xx_gpio_irq_mask_ack,
+	.irq_set_type	= ep93xx_gpio_irq_type,
+	.irq_print_chip	= ep93xx_irq_print_chip,
+	.flags			= IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
 static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc,
 				struct platform_device *pdev,
 				struct ep93xx_gpio *epg,
@@ -359,12 +372,7 @@ static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc,
 		if (!egc->eic)
 			return -ENOMEM;
 		egc->eic->irq_offset = bank->irq;
-		ic = &egc->eic->ic;
-		ic->name = devm_kasprintf(dev, GFP_KERNEL, "gpio-irq-%s", bank->label);
-		if (!ic->name)
-			return -ENOMEM;
-		ep93xx_init_irq_chip(dev, ic);
-		girq->chip = ic;
+		gpio_irq_chip_set_chip(girq, &gpio_eic_irq_chip);
 	}
 
 	if (bank->has_irq) {