ARM: mxs: request clock for timer

When mxs_timer_init() does not have a timer_clk passed in, it should
try to request clock from clkdev system.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/arm/mach-mxs/timer.c b/arch/arm/mach-mxs/timer.c
index 564a63279f18..575e8fd6bc79 100644
--- a/arch/arm/mach-mxs/timer.c
+++ b/arch/arm/mach-mxs/timer.c
@@ -20,6 +20,7 @@
  * MA 02110-1301, USA.
  */
 
+#include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/clockchips.h>
@@ -245,6 +246,14 @@ static int __init mxs_clocksource_init(struct clk *timer_clk)
 
 void __init mxs_timer_init(struct clk *timer_clk, int irq)
 {
+        if (!timer_clk) {
+                timer_clk = clk_get_sys("timrot", NULL);
+                if (IS_ERR(timer_clk)) {
+                        pr_err("%s: failed to get clk\n", __func__);
+                        return;
+                }
+        }
+
         clk_prepare_enable(timer_clk);
 
         /*