[PATCH v3 05/10] gpio: pl061: Make the irqchip immutable

Marc Zyngier
2022-04-19T14:19:40Z

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>
---
drivers/gpio/gpio-pl061.c | 32 +++++++++++++++++++++++---------
1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
index 4ecab700f23f..6464056cb6ae 100644
--- 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),
--
2.34.1