gpio: aspeed-sgpio: Convert to immutable irq_chip

Convert the driver to immutable irq-chip with a bit of
intuition.

Cc: Marc Zyngier <[e-mail]>
Acked-by: Marc Zyngier <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-aspeed-sgpio.c

···
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/seq_file.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
 
···
 
 struct aspeed_sgpio {
 	struct gpio_chip chip;
-	struct irq_chip intc;
+	struct device *dev;
 	struct clk *pclk;
 	raw_spinlock_t lock;
 	void __iomem *base;
···
 	irqd_to_aspeed_sgpio_data(d, &gpio, &bank, &bit, &offset);
 	addr = bank_reg(gpio, bank, reg_irq_enable);
 
+	/* Unmasking the IRQ */
+	if (set)
+		gpiochip_enable_irq(&gpio->chip, irqd_to_hwirq(d));
+
 	raw_spin_lock_irqsave(&gpio->lock, flags);
 
 	reg = ioread32(addr);
···
 	iowrite32(reg, addr);
 
 	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	/* Masking the IRQ */
+	if (!set)
+		gpiochip_disable_irq(&gpio->chip, irqd_to_hwirq(d));
+
+
 }
 
 static void aspeed_sgpio_irq_mask(struct irq_data *d)
···
 	chained_irq_exit(ic, desc);
 }
 
+static void aspeed_sgpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
+{
+	const struct aspeed_sgpio_bank *bank;
+	struct aspeed_sgpio *gpio;
+	u32 bit;
+	int offset;
+
+	irqd_to_aspeed_sgpio_data(d, &gpio, &bank, &bit, &offset);
+	seq_printf(p, dev_name(gpio->dev));
+}
+
+static const struct irq_chip aspeed_sgpio_irq_chip = {
+	.irq_ack = aspeed_sgpio_irq_ack,
+	.irq_mask = aspeed_sgpio_irq_mask,
+	.irq_unmask = aspeed_sgpio_irq_unmask,
+	.irq_set_type = aspeed_sgpio_set_type,
+	.irq_print_chip = aspeed_sgpio_irq_print_chip,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
 static int aspeed_sgpio_setup_irqs(struct aspeed_sgpio *gpio,
 				   struct platform_device *pdev)
 {
···
 		iowrite32(0xffffffff, bank_reg(gpio, bank, reg_irq_status));
 	}
 
-	gpio->intc.name = dev_name(&pdev->dev);
-	gpio->intc.irq_ack = aspeed_sgpio_irq_ack;
-	gpio->intc.irq_mask = aspeed_sgpio_irq_mask;
-	gpio->intc.irq_unmask = aspeed_sgpio_irq_unmask;
-	gpio->intc.irq_set_type = aspeed_sgpio_set_type;
-
 	irq = &gpio->chip.irq;
-	irq->chip = &gpio->intc;
+	gpio_irq_chip_set_chip(irq, &aspeed_sgpio_irq_chip);
 	irq->init_valid_mask = aspeed_sgpio_irq_init_valid_mask;
 	irq->handler = handle_bad_irq;
 	irq->default_type = IRQ_TYPE_NONE;
···
 	gpio->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(gpio->base))
 		return PTR_ERR(gpio->base);
+
+	gpio->dev = &pdev->dev;
 
 	pdata = device_get_match_data(&pdev->dev);
 	if (!pdata)