OMAP2+ / PM: move runtime PM implementation to use device power domains

In commit 7538e3d (PM: add support
for device power domains) a better way for handling platform-specific
power hooks was introduced.

Rather than using the platform_bus dev_pm_ops overrides
(platform_bus_set_pm_ops()), this patch moves the OMAP runtime PM
implementation over to using device power domains.

Since OMAP is the only user of platform_bus_set_pm_ops(), that
interface can be removed (and will be in a forthcoming patch.)

[rjw: Rebased on top of a previous change modifying the handling of
 power domains by the PM core so that power domain callbacks take
 precendence over subsystem-level PM callbacks.]

Signed-off-by: Kevin Hilman <khilman@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

arch/arm/mach-omap2/Makefile

@@ -59,10 +59,10 @@ endif
 # Power Management
 ifeq ($(CONFIG_PM),y)
 obj-$(CONFIG_ARCH_OMAP2)		+= pm24xx.o
-obj-$(CONFIG_ARCH_OMAP2)		+= sleep24xx.o pm_bus.o
+obj-$(CONFIG_ARCH_OMAP2)		+= sleep24xx.o
 obj-$(CONFIG_ARCH_OMAP3)		+= pm34xx.o sleep34xx.o \
-					   cpuidle34xx.o pm_bus.o
-obj-$(CONFIG_ARCH_OMAP4)		+= pm44xx.o pm_bus.o
+					   cpuidle34xx.o
+obj-$(CONFIG_ARCH_OMAP4)		+= pm44xx.o
 obj-$(CONFIG_PM_DEBUG)			+= pm-debug.o
 obj-$(CONFIG_OMAP_SMARTREFLEX)          += sr_device.o smartreflex.o
 obj-$(CONFIG_OMAP_SMARTREFLEX_CLASS3)	+= smartreflex-class3.o

arch/arm/plat-omap/omap_device.c

@@ -536,6 +536,28 @@ int omap_early_device_register(struct omap_device *od)
 	return 0;
 }
 
+static int _od_runtime_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	return omap_device_idle(pdev);
+}
+
+static int _od_runtime_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	return omap_device_enable(pdev);
+}
+
+static struct dev_power_domain omap_device_power_domain = {
+	.ops = {
+		.runtime_suspend = _od_runtime_suspend,
+		.runtime_resume = _od_runtime_resume,
+		USE_PLATFORM_PM_SLEEP_OPS
+	}
+};
+
 /**
  * omap_device_register - register an omap_device with one omap_hwmod
  * @od: struct omap_device * to register
@@ -549,6 +571,7 @@ int omap_device_register(struct omap_device *od)
 	pr_debug("omap_device: %s: registering\n", od->pdev.name);
 
 	od->pdev.dev.parent = &omap_device_parent;
+	od->pdev.dev.pwr_domain = &omap_device_power_domain;
 	return platform_device_register(&od->pdev);
 }