sh: allow runtime pm without suspend/resume callbacks

This patch updates the Runtime PM code for SuperH Mobile
to allow drivers to have NULL as pm or callback value.
With this in place there is no need for no-op functions.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/cpu/shmobile/pm_runtime.c

@@ -45,12 +45,14 @@ static int __platform_pm_runtime_resume(struct platform_device *pdev)
 
 	dev_dbg(d, "__platform_pm_runtime_resume() [%d]\n", hwblk);
 
-	if (d->driver && d->driver->pm && d->driver->pm->runtime_resume) {
+	if (d->driver) {
 		hwblk_enable(hwblk_info, hwblk);
 		ret = 0;
 
 		if (test_bit(PDEV_ARCHDATA_FLAG_SUSP, &ad->flags)) {
+			if (d->driver->pm && d->driver->pm->runtime_resume)
 				ret = d->driver->pm->runtime_resume(d);
+
 			if (!ret)
 				clear_bit(PDEV_ARCHDATA_FLAG_SUSP, &ad->flags);
 			else
@@ -73,12 +75,15 @@ static int __platform_pm_runtime_suspend(struct platform_device *pdev)
 
 	dev_dbg(d, "__platform_pm_runtime_suspend() [%d]\n", hwblk);
 
-	if (d->driver && d->driver->pm && d->driver->pm->runtime_suspend) {
+	if (d->driver) {
 		BUG_ON(!test_bit(PDEV_ARCHDATA_FLAG_IDLE, &ad->flags));
+		ret = 0;
 
+		if (d->driver->pm && d->driver->pm->runtime_suspend) {
 			hwblk_enable(hwblk_info, hwblk);
 			ret = d->driver->pm->runtime_suspend(d);
 			hwblk_disable(hwblk_info, hwblk);
+		}
 
 		if (!ret) {
 			set_bit(PDEV_ARCHDATA_FLAG_SUSP, &ad->flags);