[PATCH v2 2/3] OMAP: bus-level PM: enable use of runtime PM API for suspend/resume

[Kevin Hilman <khilman@deeprootsystems.com>]

Hook into the platform bus methods for suspend and resume and use the
runtime PM API to allow the OMAP runtime PM core (based on
omap_device) to automatically idle and enable the device on suspend
and resume.

This allows device drivers to get rid of direct management of their
clocks in their suspend/resume paths, and let omap_device do it for
them .

We currently use the _noirq (late suspend, early resume) versions of
the suspend/resume methods to ensure that the device is not disabled
too early for any drivers also using the _noirq methods.

NOTE: only works for devices with omap_hwmod support.

Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
---
 arch/arm/mach-omap2/pm_bus.c |   48 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 48 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-omap2/pm_bus.c b/arch/arm/mach-omap2/pm_bus.c
index 9719a9f..5e453dc 100644
--- a/arch/arm/mach-omap2/pm_bus.c
+++ b/arch/arm/mach-omap2/pm_bus.c
@@ -68,3 +68,51 @@ int platform_pm_runtime_idle(struct device *dev)
 };
 #endif /* CONFIG_PM_RUNTIME */
 
+#ifdef CONFIG_SUSPEND
+int platform_pm_suspend_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->suspend_noirq)
+			ret = drv->pm->suspend_noirq(dev);
+	}
+
+	/*
+	 * The DPM core has done a 'get' to prevent runtime PM
+	 * transitions during system PM.  This put is to balance
+	 * out that get so that this device can now be runtime
+	 * suspended.
+	 */
+	pm_runtime_put_sync(dev);
+
+	return ret;
+}
+
+int platform_pm_resume_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	/* 
+	 * This 'get' is to balance the 'put' in the above suspend_noirq
+	 * method so that the runtime PM usage counting is in the same
+	 * state it was when suspend was called.
+	 */
+	pm_runtime_get_sync(dev);
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->resume_noirq)
+			ret = drv->pm->resume_noirq(dev);
+	}
+
+	return ret;
+}
+#endif /* CONFIG_SUSPEND */
-- 
1.7.0.2