clocksource: sh_cmt: Runtime PM support

Add Runtime PM support to the CMT driver.

The hardware device is enabled as long as the clocksource
or the clockevent portion of the driver is used.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index dc7c033ef587142ce080e33a2b2711a94ece1d89..036e5865eb40005f026f571fd679a7db09bd4859 100644 (file)
--- 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 */
@@ -660,6 +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;
        }
 
@@ -674,6 +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;
 }