[PATCH v4 03/11] ARM: OMAP2+: timer: Add suspend-resume callbacks for clkevent device

[Dave Gerlach]

From: Vaibhav Bedia <vaibhav.bedia at ti.com>

OMAP timer code registers two timers - one as clocksource
and one as clockevent. Since AM33XX has only one usable timer
in the WKUP domain one of the timers needs suspend-resume
support to restore the configuration to pre-suspend state.

commit adc78e6 (timekeeping: Add suspend and resume
of clock event devices) introduced .suspend and .resume
callbacks for clock event devices. Leverages these
callbacks to have AM33XX clockevent timer which is
in not in WKUP domain to behave properly across system
suspend.

Signed-off-by: Vaibhav Bedia <vaibhav.bedia at ti.com>
Signed-off-by: Dave Gerlach <d-gerlach at ti.com>
---
v3->v4:
	Only use for am33xx soc now.

 arch/arm/mach-omap2/timer.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 43d03fb..6fc1748 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -128,6 +128,29 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
 	}
 }
 
+static void omap_clkevt_suspend(struct clock_event_device *unused)
+{
+	struct omap_hwmod *oh;
+
+	oh = omap_hwmod_lookup(clockevent_gpt.name);
+	if (!oh)
+		return;
+
+	omap_hwmod_idle(oh);
+}
+
+static void omap_clkevt_resume(struct clock_event_device *unused)
+{
+	struct omap_hwmod *oh;
+
+	oh = omap_hwmod_lookup(clockevent_gpt.name);
+	if (!oh)
+		return;
+
+	omap_hwmod_enable(oh);
+	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
+}
+
 static struct clock_event_device clockevent_gpt = {
 	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
 	.rating		= 300,
@@ -333,6 +356,11 @@ static void __init omap2_gp_clockevent_init(int gptimer_id,
 	clkev.id = gptimer_id;
 	clkev.errata = omap_dm_timer_get_errata();
 
+	if (soc_is_am33xx()) {
+		clockevent_gpt.suspend = omap_clkevt_suspend;
+		clockevent_gpt.resume = omap_clkevt_resume;
+	}
+
 	/*
 	 * For clock-event timers we never read the timer counter and
 	 * so we are not impacted by errata i103 and i767. Therefore,
-- 
1.9.0