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>
This commit is contained in:
Grygorii Strashko 2015-06-25 20:30:50 +03:00 committed by Linus Walleij
parent 049aaf9f7e
commit 5b76e79c77

View File

@ -522,10 +522,14 @@ static int gpiochip_irq_reqres(struct irq_data *d)
{
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 @@ static void gpiochip_irq_relres(struct irq_data *d)
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)