staging: unisys: Don't check for null before getting driver device.

The macro to convert to the driver object was giving a checkpatch warning
when it ateempted to check for a null driver. It would return NULL if it
found it, but only one location was checking to see if it was NULL.

Remove the check in the MACRO and do it prior to calling the macro if
required.
Signed-off-by: NDavid Kershner <david.kershner@unisys.com>
Reviewed-by: NTim Sell <timothy.sell@unisys.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/include/visorbus.h

@@ -104,8 +104,7 @@ struct visor_driver {
 	struct device_driver driver;
 };
 
-#define to_visor_driver(x) ((x) ? \
-	(container_of(x, struct visor_driver, driver)) : (NULL))
+#define to_visor_driver(x) (container_of(x, struct visor_driver, driver))
 
 /**
  * struct visor_device - A device type for things "plugged" into the visorbus

drivers/staging/unisys/visorbus/visorbus_main.c

@@ -1158,13 +1158,13 @@ static int visorchipset_initiate_device_pause_resume(struct visor_device *dev,
 	int err;
 	struct visor_driver *drv = NULL;
 
-	drv = to_visor_driver(dev->device.driver);
-	if (!drv)
-		return -ENODEV;
-
+	/* If no driver associated with the device nothing to pause/resume */
+	if (!dev->device.driver)
+		return 0;
 	if (dev->pausing || dev->resuming)
 		return -EBUSY;
 
+	drv = to_visor_driver(dev->device.driver);
 	if (is_pause) {
 		dev->pausing = true;
 		err = drv->pause(dev, pause_state_change_complete);