gpiolib: irqchip: prevent driver unloading if gpio is used as irq only
Now nothing prevents GPIO driver from being unloaded if its gpios
were requested as GPIO IRQs only (without calling gpio_request()).
Hence, add calls of try_module_get()/module_put() into
gpiochip_irq_reqres/relres() to track such scenario properly.
Cc: Johan Hovold <johan@kernel.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index b1b08b3..debd7c5 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -522,10 +522,14 @@
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ if (!try_module_get(chip->owner))
+ return -ENODEV;
+
if (gpiochip_lock_as_irq(chip, d->hwirq)) {
chip_err(chip,
"unable to lock HW IRQ %lu for IRQ\n",
d->hwirq);
+ module_put(chip->owner);
return -EINVAL;
}
return 0;
@@ -536,6 +540,7 @@
struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
gpiochip_unlock_as_irq(chip, d->hwirq);
+ module_put(chip->owner);
}
static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)