[PATCH] clockevents/drivers/cs5535: Un-break driver with 'set-state' interface

From: David Gstir
Date: Wed Dec 28 2016 - 16:56:50 EST

Since migrating to the 'set-state' interface the cs5535 driver causes a
crash after loading: Right after initialization, the IRQ handler
(mfgpt_tick) is triggered with clock event device in detached state. This
state not properly handled and causes a crash through NULL pointer
dereference upon calling the clockevent's event_handler.

This patch fixes this by handling the detached state the same way the
shutdown state is handled.

Fixes: 8f9327cbb6e8 ("clockevents/drivers/cs5535: Migrate to new 'set-state' interface")
Cc: stable@xxxxxxxxxxxxxxx
Cc: Andres Salomon <dilinger@xxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: David Gstir <david@xxxxxxxxxxxxx>
drivers/clocksource/cs5535-clockevt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/cs5535-clockevt.c b/drivers/clocksource/cs5535-clockevt.c
index 9a7e37cf56b0..649e0cd90805 100644
--- a/drivers/clocksource/cs5535-clockevt.c
+++ b/drivers/clocksource/cs5535-clockevt.c
@@ -117,7 +117,8 @@ static irqreturn_t mfgpt_tick(int irq, void *dev_id)
/* Turn off the clock (and clear the event) */

- if (clockevent_state_shutdown(&cs5535_clockevent))
+ if (clockevent_state_shutdown(&cs5535_clockevent) ||
+ clockevent_state_detached(&cs5535_clockevent))

/* Clear the counter */