clockevents: sun5i: Fix setup_irq init sequence

The interrupt is enabled before the handler is set. Even this bug
did not appear, it is potentially dangerous as it can lead to a
NULL pointer dereference.

Fix the error by enabling the interrupt after
clockevents_config_and_register() is called.

Cc: stable@vger.kernel.org
Signed-off-by: Yongbae Park <yongbae2@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 02268448dc85..5dcbf90b8015 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -178,10 +178,6 @@ static void __init sun5i_timer_init(struct device_node *node)
 
         ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
 
-        ret = setup_irq(irq, &sun5i_timer_irq);
-        if (ret)
-                pr_warn("failed to setup irq %d\n", irq);
-
         /* Enable timer0 interrupt */
         val = readl(timer_base + TIMER_IRQ_EN_REG);
         writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG);
@@ -191,6 +187,10 @@ static void __init sun5i_timer_init(struct device_node *node)
 
         clockevents_config_and_register(&sun5i_clockevent, rate,
                                         TIMER_SYNC_TICKS, 0xffffffff);
+
+        ret = setup_irq(irq, &sun5i_timer_irq);
+        if (ret)
+                pr_warn("failed to setup irq %d\n", irq);
 }
 CLOCKSOURCE_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer",
                        sun5i_timer_init);