From: Semen Protsenko Date: Wed, 22 Apr 2015 13:20:41 +0000 (+0300) Subject: gpio: max732x: Fix irq-events handler X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=606f13e9efa0892561e7c471242e4ad0bcaf6ecb;p=openwrt%2Fstaging%2Fblogic.git gpio: max732x: Fix irq-events handler MAX732X clears all pending interrupts on I2C read (when interrupts register is being read). Driver doesn't need to send any ACKs when interrupt was handled. So replace handle_edge_irq() with handle_simple_irq(). Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL pointer dereference in some cases. E.g. this was observed on hibernation process: Unable to handle kernel NULL pointer dereference at virtual address 0 Backtrace: (handle_edge_irq) from (resend_irqs) (resend_irqs) from (tasklet_action) (tasklet_action) from (__do_softirq) (__do_softirq) from (run_ksoftirqd) (run_ksoftirqd) from (smpboot_thread_fn) (smpboot_thread_fn) from (kthread) (kthread) from (ret_from_fork) Signed-off-by: Semen Protsenko Reviewed-by: Grygorii Strashko Signed-off-by: Linus Walleij --- diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c index 857907aecec3..aed4ca9338bc 100644 --- a/drivers/gpio/gpio-max732x.c +++ b/drivers/gpio/gpio-max732x.c @@ -528,7 +528,7 @@ static int max732x_irq_setup(struct max732x_chip *chip, ret = gpiochip_irqchip_add(&chip->gpio_chip, &max732x_irq_chip, irq_base, - handle_edge_irq, + handle_simple_irq, IRQ_TYPE_NONE); if (ret) { dev_err(&client->dev,