HID: add hid_hw_open/close/power() handlers

Instead of exposing the guts of hid->ll_driver relationship to HID
sub-drivers provide these helpers to encapsulate the details.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index 8a4b32d..5aefe73 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -193,15 +193,13 @@
 
 	dev = hidraw_table[minor];
 	if (!dev->open++) {
-		if (dev->hid->ll_driver->power) {
-			err = dev->hid->ll_driver->power(dev->hid, PM_HINT_FULLON);
-			if (err < 0)
-				goto out_unlock;
-		}
-		err = dev->hid->ll_driver->open(dev->hid);
+		err = hid_hw_power(dev->hid, PM_HINT_FULLON);
+		if (err < 0)
+			goto out_unlock;
+
+		err = hid_hw_open(dev->hid);
 		if (err < 0) {
-			if (dev->hid->ll_driver->power)
-				dev->hid->ll_driver->power(dev->hid, PM_HINT_NORMAL);
+			hid_hw_power(dev->hid, PM_HINT_NORMAL);
 			dev->open--;
 		}
 	}
@@ -230,9 +228,8 @@
 	dev = hidraw_table[minor];
 	if (!--dev->open) {
 		if (list->hidraw->exist) {
-			if (dev->hid->ll_driver->power)
-				dev->hid->ll_driver->power(dev->hid, PM_HINT_NORMAL);
-			dev->hid->ll_driver->close(dev->hid);
+			hid_hw_power(dev->hid, PM_HINT_NORMAL);
+			hid_hw_close(dev->hid);
 		} else {
 			kfree(list->hidraw);
 		}
@@ -434,7 +431,7 @@
 	device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
 
 	if (hidraw->open) {
-		hid->ll_driver->close(hid);
+		hid_hw_close(hid);
 		wake_up_interruptible(&hidraw->wait);
 	} else {
 		kfree(hidraw);