diff options
-rw-r--r-- | drivers/gpio/gpiolib.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index c6afbf434366..16c16414f721 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -14,6 +14,7 @@ #include <linux/idr.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/irqdesc.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/lockdep.h> @@ -713,6 +714,45 @@ bool gpiochip_line_is_valid(const struct gpio_chip *gc, } EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); +static void gpiod_free_irqs(struct gpio_desc *desc) +{ + int irq = gpiod_to_irq(desc); + struct irq_desc *irqd = irq_to_desc(irq); + void *cookie; + + for (;;) { + /* + * Make sure the action doesn't go away while we're + * dereferencing it. Retrieve and store the cookie value. + * If the irq is freed after we release the lock, that's + * alright - the underlying maple tree lookup will return NULL + * and nothing will happen in free_irq(). + */ + scoped_guard(mutex, &irqd->request_mutex) { + if (!irq_desc_has_action(irqd)) + return; + + cookie = irqd->action->dev_id; + } + + free_irq(irq, cookie); + } +} + +/* + * The chip is going away but there may be users who had requested interrupts + * on its GPIO lines who have no idea about its removal and have no way of + * being notified about it. We need to free any interrupts still in use here or + * we'll leak memory and resources (like procfs files). + */ +static void gpiochip_free_remaining_irqs(struct gpio_chip *gc) +{ + struct gpio_desc *desc; + + for_each_gpio_desc_with_flag(gc, desc, FLAG_USED_AS_IRQ) + gpiod_free_irqs(desc); +} + static void gpiodev_release(struct device *dev) { struct gpio_device *gdev = to_gpio_device(dev); @@ -1125,6 +1165,7 @@ void gpiochip_remove(struct gpio_chip *gc) /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ gpiochip_sysfs_unregister(gdev); gpiochip_free_hogs(gc); + gpiochip_free_remaining_irqs(gc); scoped_guard(mutex, &gpio_devices_lock) list_del_rcu(&gdev->list); |