gpio: pl061: Make the irqchip immutable

Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-6-maz@kernel.org

diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
index 4ecab700f23f6cc43c79a0bb05a0f1844e499faa..6464056cb6ae523a232e4c1f433110f5ebadaf1c 100644 (file)
--- a/drivers/gpio/gpio-pl061.c
+++ b/drivers/gpio/gpio-pl061.c
@@ -52,7 +52,6 @@ struct pl061 {
 
        void __iomem            *base;
        struct gpio_chip        gc;
-       struct irq_chip         irq_chip;
        int                     parent_irq;
 
 #ifdef CONFIG_PM
@@ -241,6 +240,8 @@ static void pl061_irq_mask(struct irq_data *d)
        gpioie = readb(pl061->base + GPIOIE) & ~mask;
        writeb(gpioie, pl061->base + GPIOIE);
        raw_spin_unlock(&pl061->lock);
+
+       gpiochip_disable_irq(gc, d->hwirq);
 }
 
 static void pl061_irq_unmask(struct irq_data *d)
@@ -250,6 +251,8 @@ static void pl061_irq_unmask(struct irq_data *d)
        u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
        u8 gpioie;
 
+       gpiochip_enable_irq(gc, d->hwirq);
+
        raw_spin_lock(&pl061->lock);
        gpioie = readb(pl061->base + GPIOIE) | mask;
        writeb(gpioie, pl061->base + GPIOIE);
@@ -283,6 +286,24 @@ static int pl061_irq_set_wake(struct irq_data *d, unsigned int state)
        return irq_set_irq_wake(pl061->parent_irq, state);
 }
 
+static void pl061_irq_print_chip(struct irq_data *data, struct seq_file *p)
+{
+       struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+
+       seq_printf(p, dev_name(gc->parent));
+}
+
+static const struct irq_chip pl061_irq_chip = {
+       .irq_ack                = pl061_irq_ack,
+       .irq_mask               = pl061_irq_mask,
+       .irq_unmask             = pl061_irq_unmask,
+       .irq_set_type           = pl061_irq_type,
+       .irq_set_wake           = pl061_irq_set_wake,
+       .irq_print_chip         = pl061_irq_print_chip,
+       .flags                  = IRQCHIP_IMMUTABLE,
+       GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
 static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
 {
        struct device *dev = &adev->dev;
@@ -315,13 +336,6 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
        /*
         * irq_chip support
         */
-       pl061->irq_chip.name = dev_name(dev);
-       pl061->irq_chip.irq_ack = pl061_irq_ack;
-       pl061->irq_chip.irq_mask = pl061_irq_mask;
-       pl061->irq_chip.irq_unmask = pl061_irq_unmask;
-       pl061->irq_chip.irq_set_type = pl061_irq_type;
-       pl061->irq_chip.irq_set_wake = pl061_irq_set_wake;
-
        writeb(0, pl061->base + GPIOIE); /* disable irqs */
        irq = adev->irq[0];
        if (!irq)
@@ -329,7 +343,7 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
        pl061->parent_irq = irq;
 
        girq = &pl061->gc.irq;
-       girq->chip = &pl061->irq_chip;
+       gpio_irq_chip_set_chip(girq, &pl061_irq_chip);
        girq->parent_handler = pl061_irq_handler;
        girq->num_parents = 1;
        girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),