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 <semen.protsenko@globallogic.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 857907a..aed4ca93 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -528,7 +528,7 @@
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,