On Wednesday 23 February 2011, Grant Likely wrote:

arch/powerpc/kernel/ibmebus.c is the only remaining user of the
of_bus_type support code for initializing the bus and registering
drivers.  All others have either been switched to the vanilla platform
bus or already have their own infrastructure.

This patch moves the functionality that ibmebus is using out of
drivers/of/{platform,device}.c and into ibmebus.c where it is actually
used.  Also renames the moved symbols from of_platform_* to
ibmebus_bus_* to reflect the actual usage.

This patch is part of moving all of the of_platform_bus_type users
over to the platform_bus_type.

Signed-off-by: Grant Likely <redacted>

The ibmebus is essentially the platform bus of the IBM Power Systems (a.k.a.
pSeries a.k.a. System p), I think it would make a lot of sense to convert
the two drivers (ehca and ehea) on this bus into platform drivers as well.

The original reason for this bus was to provide a different IOMMU for them
than what is used on the PCI devices. This should now be possible in simpler
ways.
 

+static void ibmebus_bus_device_shutdown(struct device *dev)
+{
+	struct platform_device *of_dev = to_platform_device(dev);
+	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);
+
+	if (dev->driver && drv->shutdown)
+		drv->shutdown(of_dev);
+}

neither of the drivers provides a shutdown function.

+#ifdef CONFIG_PM_SLEEP
+static int ibmebus_bus_legacy_suspend(struct device *dev, pm_message_t mesg)
+{
+	struct platform_device *of_dev = to_platform_device(dev);
+	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);
+	int ret = 0;
+
+	if (dev->driver && drv->suspend)
+		ret = drv->suspend(of_dev, mesg);
+	return ret;
+}
+
+static int ibmebus_bus_legacy_resume(struct device *dev)
+{
+	struct platform_device *of_dev = to_platform_device(dev);
+	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);
+	int ret = 0;
+
+	if (dev->driver && drv->resume)
+		ret = drv->resume(of_dev);
+	return ret;
+}
+
+static int ibmebus_bus_pm_prepare(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (drv && drv->pm && drv->pm->prepare)
+		ret = drv->pm->prepare(dev);
+
+	return ret;
+}
+
+static void ibmebus_bus_pm_complete(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+
+	if (drv && drv->pm && drv->pm->complete)
+		drv->pm->complete(dev);
+}
+
+#ifdef CONFIG_SUSPEND
+
+static int ibmebus_bus_pm_suspend(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->suspend)
+			ret = drv->pm->suspend(dev);
+	} else {
+		ret = ibmebus_bus_legacy_suspend(dev, PMSG_SUSPEND);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_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);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_resume(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->resume)
+			ret = drv->pm->resume(dev);
+	} else {
+		ret = ibmebus_bus_legacy_resume(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_resume_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->resume_noirq)
+			ret = drv->pm->resume_noirq(dev);
+	}
+
+	return ret;
+}

These are also unused in the drivers.

+#ifdef CONFIG_HIBERNATION
+
+static int ibmebus_bus_pm_freeze(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->freeze)
+			ret = drv->pm->freeze(dev);
+	} else {
+		ret = ibmebus_bus_legacy_suspend(dev, PMSG_FREEZE);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_freeze_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->freeze_noirq)
+			ret = drv->pm->freeze_noirq(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_thaw(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->thaw)
+			ret = drv->pm->thaw(dev);
+	} else {
+		ret = ibmebus_bus_legacy_resume(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_thaw_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->thaw_noirq)
+			ret = drv->pm->thaw_noirq(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_poweroff(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->poweroff)
+			ret = drv->pm->poweroff(dev);
+	} else {
+		ret = ibmebus_bus_legacy_suspend(dev, PMSG_HIBERNATE);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_poweroff_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->poweroff_noirq)
+			ret = drv->pm->poweroff_noirq(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_restore(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->restore)
+			ret = drv->pm->restore(dev);
+	} else {
+		ret = ibmebus_bus_legacy_resume(dev);
+	}
+
+	return ret;
+}
+
+static int ibmebus_bus_pm_restore_noirq(struct device *dev)
+{
+	struct device_driver *drv = dev->driver;
+	int ret = 0;
+
+	if (!drv)
+		return 0;
+
+	if (drv->pm) {
+		if (drv->pm->restore_noirq)
+			ret = drv->pm->restore_noirq(dev);
+	}
+
+	return ret;
+}

And these, too.

	Arnd