usb: common: Patch simplify usb_decode_set_clear_feature function.

Patch adds usb_decode_test_mode and usb_decode_device_feature functions,
which allow to make more readable and simplify the
usb_decode_set_clear_feature function.

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/common/debug.c b/drivers/usb/common/debug.c
index d5a469b..60a9f70a 100644
--- a/drivers/usb/common/debug.c
+++ b/drivers/usb/common/debug.c
@@ -30,58 +30,55 @@ static void usb_decode_get_status(__u8 bRequestType, __u16 wIndex,
 	}
 }
 
-static void usb_decode_set_clear_feature(__u8 bRequestType, __u8 bRequest,
-					 __u16 wValue, __u16 wIndex,
-					 char *str, size_t size)
+static const char *usb_decode_device_feature(u16 wValue)
+{
+	switch (wValue) {
+	case USB_DEVICE_SELF_POWERED:
+		return "Self Powered";
+	case USB_DEVICE_REMOTE_WAKEUP:
+		return "Remote Wakeup";
+	case USB_DEVICE_TEST_MODE:
+		return "Test Mode";
+	case USB_DEVICE_U1_ENABLE:
+		return "U1 Enable";
+	case USB_DEVICE_U2_ENABLE:
+		return "U2 Enable";
+	case USB_DEVICE_LTM_ENABLE:
+		return "LTM Enable";
+	default:
+		return "UNKNOWN";
+	}
+}
+
+static const char *usb_decode_test_mode(u16 wIndex)
+{
+	switch (wIndex) {
+	case TEST_J:
+		return ": TEST_J";
+	case TEST_K:
+		return ": TEST_K";
+	case TEST_SE0_NAK:
+		return ": TEST_SE0_NAK";
+	case TEST_PACKET:
+		return ": TEST_PACKET";
+	case TEST_FORCE_EN:
+		return ": TEST_FORCE_EN";
+	default:
+		return ": UNKNOWN";
+	}
+}
+
+static void usb_decode_set_clear_feature(__u8 bRequestType,
+					 __u8 bRequest, __u16 wValue,
+					 __u16 wIndex, char *str, size_t size)
 {
 	switch (bRequestType & USB_RECIP_MASK) {
 	case USB_RECIP_DEVICE:
 		snprintf(str, size, "%s Device Feature(%s%s)",
 			 bRequest == USB_REQ_CLEAR_FEATURE ? "Clear" : "Set",
-			 ({char *s;
-				switch (wValue) {
-				case USB_DEVICE_SELF_POWERED:
-					s = "Self Powered";
-					break;
-				case USB_DEVICE_REMOTE_WAKEUP:
-					s = "Remote Wakeup";
-					break;
-				case USB_DEVICE_TEST_MODE:
-					s = "Test Mode";
-					break;
-				case USB_DEVICE_U1_ENABLE:
-					s = "U1 Enable";
-					break;
-				case USB_DEVICE_U2_ENABLE:
-					s = "U2 Enable";
-					break;
-				case USB_DEVICE_LTM_ENABLE:
-					s = "LTM Enable";
-					break;
-				default:
-					s = "UNKNOWN";
-				} s; }),
+			 usb_decode_device_feature(wValue),
 			 wValue == USB_DEVICE_TEST_MODE ?
-			 ({ char *s;
-				switch (wIndex) {
-				case TEST_J:
-					s = ": TEST_J";
-					break;
-				case TEST_K:
-					s = ": TEST_K";
-					break;
-				case TEST_SE0_NAK:
-					s = ": TEST_SE0_NAK";
-					break;
-				case TEST_PACKET:
-					s = ": TEST_PACKET";
-					break;
-				case TEST_FORCE_EN:
-					s = ": TEST_FORCE_EN";
-					break;
-				default:
-					s = ": UNKNOWN";
-				} s; }) : "");
+			 usb_decode_test_mode(wIndex) : "");
 		break;
 	case USB_RECIP_INTERFACE:
 		snprintf(str, size, "%s Interface Feature(%s)",