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

Cc: Marc Zyngier <maz@kernel.org>
Tested-by: Joel Stanley <joel@jms.id.au>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <redacted>
---
 drivers/gpio/gpio-aspeed.c | 44 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 38 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index a94da80d3a95..9c4852de2733 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c

@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/seq_file.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>

@@ -53,7 +54,7 @@ struct aspeed_gpio_config {
  */
 struct aspeed_gpio {
        struct gpio_chip chip;
-       struct irq_chip irqc;
+       struct device *dev;
        raw_spinlock_t lock;
        void __iomem *base;
        int irq;

@@ -566,6 +567,10 @@ static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)

        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);
        copro = aspeed_gpio_copro_request(gpio, offset);

@@ -579,6 +584,10 @@ static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
        if (copro)
                aspeed_gpio_copro_release(gpio, offset);
        raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+       /* Masking the IRQ */
+       if (!set)
+               gpiochip_disable_irq(&gpio->chip, irqd_to_hwirq(d));
 }

 static void aspeed_gpio_irq_mask(struct irq_data *d)

@@ -1080,6 +1089,30 @@ int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
 }
 EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);

+static void aspeed_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
+{
+       const struct aspeed_gpio_bank *bank;
+       struct aspeed_gpio *gpio;
+       u32 bit;
+       int rc, offset;
+
+       rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);

+       if (rc)
+               return;
+
+       seq_printf(p, dev_name(gpio->dev));
+}
+
+static const struct irq_chip aspeed_gpio_irq_chip = {
+       .irq_ack = aspeed_gpio_irq_ack,
+       .irq_mask = aspeed_gpio_irq_mask,
+       .irq_unmask = aspeed_gpio_irq_unmask,
+       .irq_set_type = aspeed_gpio_set_type,
+       .irq_print_chip = aspeed_gpio_irq_print_chip,
+       .flags = IRQCHIP_IMMUTABLE,
+       GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
 /*
  * Any banks not specified in a struct aspeed_bank_props array are assumed to
  * have the properties:

@@ -1149,6 +1182,8 @@ static int __init aspeed_gpio_probe(struct platform_device *pdev)
        if (IS_ERR(gpio->base))
                return PTR_ERR(gpio->base);

+       gpio->dev = &pdev->dev;
+
        raw_spin_lock_init(&gpio->lock);

        gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);

@@ -1208,12 +1243,9 @@ static int __init aspeed_gpio_probe(struct platform_device *pdev)

                gpio->irq = rc;
                girq = &gpio->chip.irq;
-               girq->chip = &gpio->irqc;
+               gpio_irq_chip_set_chip(girq, &aspeed_gpio_irq_chip);
                girq->chip->name = dev_name(&pdev->dev);
-               girq->chip->irq_ack = aspeed_gpio_irq_ack;
-               girq->chip->irq_mask = aspeed_gpio_irq_mask;
-               girq->chip->irq_unmask = aspeed_gpio_irq_unmask;
-               girq->chip->irq_set_type = aspeed_gpio_set_type;
+