Commit ff7a1790 authored Jun 19, 2023 by Michael Walle Committed by Bartosz Golaszewski Jun 19, 2023

gpiolib: Fix irq_domain resource tracking for gpiochip_irqchip_add_domain()



Up until commit 6a45b0e2 ("gpiolib: Introduce
gpiochip_irqchip_add_domain()") all irq_domains were allocated
by gpiolib itself and thus gpiolib also takes care of freeing it.

With gpiochip_irqchip_add_domain() a user of gpiolib can associate an
irq_domain with the gpio_chip. This irq_domain is not managed by
gpiolib and therefore must not be freed by gpiolib.

Fixes: 6a45b0e2 ("gpiolib: Introduce gpiochip_irqchip_add_domain()")
Reported-by: Jiawen Wu <jiawenwu@trustnetic.com>
Signed-off-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

parent c1bcb976

drivers/gpio/gpiolib.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -1745,7 +1745,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gc)
		}

		/* Remove all IRQ mappings and delete the domain */
		if (gc->irq.domain) {
		if (!gc->irq.domain_is_allocated_externally && gc->irq.domain) {
		unsigned int irq;

		for (offset = 0; offset < gc->ngpio; offset++) {
		@@ -1791,6 +1791,7 @@ int gpiochip_irqchip_add_domain(struct gpio_chip *gc,

		gc->to_irq = gpiochip_to_irq;
		gc->irq.domain = domain;
		gc->irq.domain_is_allocated_externally = true;

		/*
		* Using barrier() here to prevent compiler from reordering

include/linux/gpio/driver.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -251,6 +251,14 @@ struct gpio_irq_chip {
		*/
		bool initialized;

		/**
		* @domain_is_allocated_externally:
		*
		* True it the irq_domain was allocated outside of gpiolib, in which
		* case gpiolib won't free the irq_domain itself.
		*/
		bool domain_is_allocated_externally;

		/**
		* @init_hw: optional routine to initialize hardware before
		* an IRQ chip will be added. This is quite useful when