sh: CMT: Introduce clocksource/clock events suspend/resume routines

Introduce suspend/resume routines for SH CMT clock event devices and
modify the suspend/resume routines for SH CMT clock sources such that
if those devices belong to a PM domain, the generic PM domains
framework will be notified that the given domain may be turned off
(during system suspend) or that it has to be turned on (during system
resume).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index 98b06ba..c06d27f 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -464,9 +464,20 @@
 	sh_cmt_stop(cs_to_sh_cmt(cs), FLAG_CLOCKSOURCE);
 }
 
+static void sh_cmt_clocksource_suspend(struct clocksource *cs)
+{
+	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
+
+	sh_cmt_stop(p, FLAG_CLOCKSOURCE);
+	pm_genpd_syscore_poweroff(&p->pdev->dev);
+}
+
 static void sh_cmt_clocksource_resume(struct clocksource *cs)
 {
-	sh_cmt_start(cs_to_sh_cmt(cs), FLAG_CLOCKSOURCE);
+	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
+
+	pm_genpd_syscore_poweron(&p->pdev->dev);
+	sh_cmt_start(p, FLAG_CLOCKSOURCE);
 }
 
 static int sh_cmt_register_clocksource(struct sh_cmt_priv *p,
@@ -479,7 +490,7 @@
 	cs->read = sh_cmt_clocksource_read;
 	cs->enable = sh_cmt_clocksource_enable;
 	cs->disable = sh_cmt_clocksource_disable;
-	cs->suspend = sh_cmt_clocksource_disable;
+	cs->suspend = sh_cmt_clocksource_suspend;
 	cs->resume = sh_cmt_clocksource_resume;
 	cs->mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
@@ -562,6 +573,16 @@
 	return 0;
 }
 
+static void sh_cmt_clock_event_suspend(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweroff(&ced_to_sh_cmt(ced)->pdev->dev);
+}
+
+static void sh_cmt_clock_event_resume(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweron(&ced_to_sh_cmt(ced)->pdev->dev);
+}
+
 static void sh_cmt_register_clockevent(struct sh_cmt_priv *p,
 				       char *name, unsigned long rating)
 {
@@ -576,6 +597,8 @@
 	ced->cpumask = cpumask_of(0);
 	ced->set_next_event = sh_cmt_clock_event_next;
 	ced->set_mode = sh_cmt_clock_event_mode;
+	ced->suspend = sh_cmt_clock_event_suspend;
+	ced->resume = sh_cmt_clock_event_resume;
 
 	dev_info(&p->pdev->dev, "used for clock events\n");
 	clockevents_register_device(ced);
@@ -690,8 +713,12 @@
 	struct sh_cmt_priv *p = platform_get_drvdata(pdev);
 	int ret;
 
-	if (!is_early_platform_device(pdev))
-		pm_genpd_dev_always_on(&pdev->dev, true);
+	if (!is_early_platform_device(pdev)) {
+		struct sh_timer_config *cfg = pdev->dev.platform_data;
+
+		if (cfg->clocksource_rating || cfg->clockevent_rating)
+			pm_genpd_dev_always_on(&pdev->dev, true);
+	}
 
 	if (p) {
 		dev_info(&pdev->dev, "kept as earlytimer\n");