staging: line6: Pass *_init() `usb_line6' pointers

Casting the `struct usb_line6' pointer at the call point makes the code
difficult to read.  This is substantially cleaned up by moving the cast
into the callees.

Signed-off-by: Chris Rorvick <chris@rorvick.com>
Reviewed-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

drivers/staging/line6/driver.c

@@ -959,33 +959,26 @@ static int line6_probe(struct usb_interface *interface,
 	case LINE6_POCKETPOD:
 	case LINE6_PODXT:
 	case LINE6_PODXTPRO:
-		ret = line6_pod_init(interface, (struct usb_line6_pod *)line6);
+		ret = line6_pod_init(interface, line6);
 		break;
 
 	case LINE6_PODHD300:
 	case LINE6_PODHD400:
 	case LINE6_PODHD500_0:
 	case LINE6_PODHD500_1:
-		ret = line6_podhd_init(interface,
-				       (struct usb_line6_podhd *)line6);
+		ret = line6_podhd_init(interface, line6);
 		break;
 
 	case LINE6_PODXTLIVE_POD:
-		ret =
-		    line6_pod_init(interface,
-				   (struct usb_line6_pod *)line6);
+		ret = line6_pod_init(interface, line6);
 		break;
 
 	case LINE6_PODXTLIVE_VARIAX:
-		ret =
-		    line6_variax_init(interface,
-				      (struct usb_line6_variax *)line6);
+		ret = line6_variax_init(interface, line6);
 		break;
 
 	case LINE6_VARIAX:
-		ret =
-		    line6_variax_init(interface,
-				      (struct usb_line6_variax *)line6);
+		ret = line6_variax_init(interface, line6);
 		break;
 
 	case LINE6_PODSTUDIO_GX:
@@ -995,9 +988,7 @@ static int line6_probe(struct usb_interface *interface,
 	case LINE6_TONEPORT_UX1:
 	case LINE6_TONEPORT_UX2:
 	case LINE6_GUITARPORT:
-		ret =
-		    line6_toneport_init(interface,
-					(struct usb_line6_toneport *)line6);
+		ret = line6_toneport_init(interface, line6);
 		break;
 
 	default:

drivers/staging/line6/pod.c

@@ -353,10 +353,10 @@ static int pod_create_files2(struct device *dev)
 	 Try to init POD device.
 */
 static int pod_try_init(struct usb_interface *interface,
-			struct usb_line6_pod *pod)
+			struct usb_line6 *line6)
 {
 	int err;
-	struct usb_line6 *line6 = &pod->line6;
+	struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
 
 	init_timer(&pod->startup_timer);
 	INIT_WORK(&pod->startup_work, pod_startup4);
@@ -409,9 +409,9 @@ static int pod_try_init(struct usb_interface *interface,
 /*
 	 Init POD device (and clean up in case of failure).
 */
-int line6_pod_init(struct usb_interface *interface, struct usb_line6_pod *pod)
+int line6_pod_init(struct usb_interface *interface, struct usb_line6 *line6)
 {
-	int err = pod_try_init(interface, pod);
+	int err = pod_try_init(interface, line6);
 
 	if (err < 0)
 		pod_destruct(interface);

drivers/staging/line6/pod.h

@@ -88,7 +88,7 @@ struct usb_line6_pod {
 
 extern void line6_pod_disconnect(struct usb_interface *interface);
 extern int line6_pod_init(struct usb_interface *interface,
-			  struct usb_line6_pod *pod);
+			  struct usb_line6 *line6);
 extern void line6_pod_process_message(struct usb_line6_pod *pod);
 
 #endif

drivers/staging/line6/podhd.c

@@ -121,9 +121,9 @@ static int podhd_try_init(struct usb_interface *interface,
 /*
 	Init POD HD device (and clean up in case of failure).
 */
-int line6_podhd_init(struct usb_interface *interface,
-		     struct usb_line6_podhd *podhd)
+int line6_podhd_init(struct usb_interface *interface, struct usb_line6 *line6)
 {
+	struct usb_line6_podhd *podhd = (struct usb_line6_podhd *) line6;
 	int err = podhd_try_init(interface, podhd);
 
 	if (err < 0)

drivers/staging/line6/podhd.h

@@ -25,6 +25,6 @@ struct usb_line6_podhd {
 
 extern void line6_podhd_disconnect(struct usb_interface *interface);
 extern int line6_podhd_init(struct usb_interface *interface,
-			    struct usb_line6_podhd *podhd);
+			    struct usb_line6 *line6);
 
 #endif /* PODHD_H */

drivers/staging/line6/toneport.c

@@ -339,10 +339,10 @@ static void toneport_setup(struct usb_line6_toneport *toneport)
 	 Try to init Toneport device.
 */
 static int toneport_try_init(struct usb_interface *interface,
-			     struct usb_line6_toneport *toneport)
+			     struct usb_line6 *line6)
 {
 	int err;
-	struct usb_line6 *line6 = &toneport->line6;
+	struct usb_line6_toneport *toneport =  (struct usb_line6_toneport *) line6;
 
 	if ((interface == NULL) || (toneport == NULL))
 		return -ENODEV;
@@ -411,9 +411,9 @@ static int toneport_try_init(struct usb_interface *interface,
 	 Init Toneport device (and clean up in case of failure).
 */
 int line6_toneport_init(struct usb_interface *interface,
-			struct usb_line6_toneport *toneport)
+			struct usb_line6 *line6)
 {
-	int err = toneport_try_init(interface, toneport);
+	int err = toneport_try_init(interface, line6);
 
 	if (err < 0)
 		toneport_destruct(interface);

drivers/staging/line6/toneport.h

@@ -46,7 +46,7 @@ struct usb_line6_toneport {
 
 extern void line6_toneport_disconnect(struct usb_interface *interface);
 extern int line6_toneport_init(struct usb_interface *interface,
-			       struct usb_line6_toneport *toneport);
+			       struct usb_line6 *line6);
 extern void line6_toneport_reset_resume(struct usb_line6_toneport *toneport);
 
 #endif

drivers/staging/line6/variax.c

@@ -174,8 +174,9 @@ static void variax_destruct(struct usb_interface *interface)
 	 Try to init workbench device.
 */
 static int variax_try_init(struct usb_interface *interface,
-			   struct usb_line6_variax *variax)
+			   struct usb_line6 *line6)
 {
+	struct usb_line6_variax *variax = (struct usb_line6_variax *) line6;
 	int err;
 
 	init_timer(&variax->startup_timer1);
@@ -212,10 +213,9 @@ static int variax_try_init(struct usb_interface *interface,
 /*
 	 Init workbench device (and clean up in case of failure).
 */
-int line6_variax_init(struct usb_interface *interface,
-		      struct usb_line6_variax *variax)
+int line6_variax_init(struct usb_interface *interface, struct usb_line6 *line6)
 {
-	int err = variax_try_init(interface, variax);
+	int err = variax_try_init(interface, line6);
 
 	if (err < 0)
 		variax_destruct(interface);

drivers/staging/line6/variax.h

@@ -66,7 +66,7 @@ struct usb_line6_variax {
 
 extern void line6_variax_disconnect(struct usb_interface *interface);
 extern int line6_variax_init(struct usb_interface *interface,
-			     struct usb_line6_variax *variax);
+			     struct usb_line6 *line6);
 extern void line6_variax_process_message(struct usb_line6_variax *variax);
 
 #endif