[REPOST PATCH] ARM: sunxi: stop timer from ticking before enabling interrupts

[Marc Zyngier]

The sun4i timer can still be ticking when we enable the interrupt.
If another timer is actually used (A7 architected timer, for example),
odds are that the interrupt will eventually fire with the event_handler
pointer being NULL.

The obvious fix it to stop the timer before registering the interrupt.

Observed and tested on sun7i (cubietruck).

Cc: Daniel Lezcano <daniel.lezcano at linaro.org>
Acked-by: Maxime Ripard <maxime.ripard at free-electrons.com>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
Daniel,

Maxime asked me to forward this to you directly. Please consider merging
it for 3.13.

Thanks,

	M.

 drivers/clocksource/sun4i_timer.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 2fb4695..a4f6119 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -179,6 +179,9 @@ static void __init sun4i_timer_init(struct device_node *node)
 	writel(TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
 	       timer_base + TIMER_CTL_REG(0));
 
+	/* Make sure timer is stopped before playing with interrupts */
+	sun4i_clkevt_time_stop(0);
+
 	ret = setup_irq(irq, &sun4i_timer_irq);
 	if (ret)
 		pr_warn("failed to setup irq %d\n", irq);
-- 
1.8.2.3