1 files changed, 17 insertions, 14 deletions

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index f975d24890fa..036e5865eb40 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -24,6 +24,7 @@
 #include <linux/ioport.h>
 #include <linux/io.h>
 #include <linux/clk.h>
+#include <linux/pm_runtime.h>
 #include <linux/irq.h>
 #include <linux/err.h>
 #include <linux/clocksource.h>
@@ -152,10 +153,12 @@ static int sh_cmt_enable(struct sh_cmt_priv *p, unsigned long *rate)
 {
 	int ret;
 
-	/* enable clock */
+	/* wake up device and enable clock */
+	pm_runtime_get_sync(&p->pdev->dev);
 	ret = clk_enable(p->clk);
 	if (ret) {
 		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		pm_runtime_put_sync(&p->pdev->dev);
 		return ret;
 	}
 
@@ -187,8 +190,9 @@ static void sh_cmt_disable(struct sh_cmt_priv *p)
 	/* disable interrupts in CMT block */
 	sh_cmt_write(p, CMCSR, 0);
 
-	/* stop clock */
+	/* stop clock and mark device as idle */
 	clk_disable(p->clk);
+	pm_runtime_put_sync(&p->pdev->dev);
 }
 
 /* private flags */
@@ -416,11 +420,15 @@ static cycle_t sh_cmt_clocksource_read(struct clocksource *cs)
 
 static int sh_cmt_clocksource_enable(struct clocksource *cs)
 {
+	int ret;
 	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
 
 	p->total_cycles = 0;
 
-	return sh_cmt_start(p, FLAG_CLOCKSOURCE);
+	ret = sh_cmt_start(p, FLAG_CLOCKSOURCE);
+	if (!ret)
+		__clocksource_updatefreq_hz(cs, p->rate);
+	return ret;
 }
 
 static void sh_cmt_clocksource_disable(struct clocksource *cs)
@@ -448,19 +456,10 @@ static int sh_cmt_register_clocksource(struct sh_cmt_priv *p,
 	cs->mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
 
-	/* clk_get_rate() needs an enabled clock */
-	clk_enable(p->clk);
-	p->rate = clk_get_rate(p->clk) / ((p->width == 16) ? 512 : 8);
-	clk_disable(p->clk);
-
-	/* TODO: calculate good shift from rate and counter bit width */
-	cs->shift = 0;
-	cs->mult = clocksource_hz2mult(p->rate, cs->shift);
-
 	dev_info(&p->pdev->dev, "used as clock source\n");
 
-	clocksource_register(cs);
-
+	/* Register with dummy 1 Hz value, gets updated in ->enable() */
+	clocksource_register_hz(cs, 1);
 	return 0;
 }
 
@@ -665,6 +664,7 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
 
 	if (p) {
 		dev_info(&pdev->dev, "kept as earlytimer\n");
+		pm_runtime_enable(&pdev->dev);
 		return 0;
 	}
 
@@ -679,6 +679,9 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
 		kfree(p);
 		platform_set_drvdata(pdev, NULL);
 	}
+
+	if (!is_early_platform_device(pdev))
+		pm_runtime_enable(&pdev->dev);
 	return ret;
 }