sh: CMT suspend/resume

This patch updates the SuperH CMT driver with suspend and resume
callbacks for the suspend-to-ram case. This patch stops the CMT
channel at suspend time to avoid unwanted wake up events.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index 2964f5f4a7ef..6b3e0c2f33e2 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -40,6 +40,7 @@ struct sh_cmt_priv {
         struct platform_device *pdev;
 
         unsigned long flags;
+        unsigned long flags_suspend;
         unsigned long match_value;
         unsigned long next_match_value;
         unsigned long max_match_value;
@@ -667,11 +668,38 @@ static int __devexit sh_cmt_remove(struct platform_device *pdev)
         return -EBUSY; /* cannot unregister clockevent and clocksource */
 }
 
+static int sh_cmt_suspend(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct sh_cmt_priv *p = platform_get_drvdata(pdev);
+
+        /* save flag state and stop CMT channel */
+        p->flags_suspend = p->flags;
+        sh_cmt_stop(p, p->flags);
+        return 0;
+}
+
+static int sh_cmt_resume(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct sh_cmt_priv *p = platform_get_drvdata(pdev);
+
+        /* start CMT channel from saved state */
+        sh_cmt_start(p, p->flags_suspend);
+        return 0;
+}
+
+static struct dev_pm_ops sh_cmt_dev_pm_ops = {
+        .suspend = sh_cmt_suspend,
+        .resume = sh_cmt_resume,
+};
+
 static struct platform_driver sh_cmt_device_driver = {
         .probe          = sh_cmt_probe,
         .remove         = __devexit_p(sh_cmt_remove),
         .driver         = {
                 .name   = "sh_cmt",
+                .pm     = &sh_cmt_dev_pm_ops,
         }
 };