usb: chipidea: udc: refine isr_tr_complete_handler

Matthieu CASTET and Michael Grzeschik mentioned isr_tr_complete_handler
is a bit messy at below:
http://marc.info/?l=linux-usb&m=139047775001152&w=2

This commit creates a new function isr_setup_packet_handler to handle
setup packet, it makes isr_tr_complete_handler easy to read.

This is no functional change at this commit, tested with g_mass_storage
and g_ether.

Cc: Michael Grzeschik <mgr@pengutronix.de>
Cc: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/udc.c

@@ -949,45 +949,19 @@ __acquires(hwep->lock)
 }
 
 /**
- * isr_tr_complete_handler: transaction complete interrupt handler
+ * isr_setup_packet_handler: setup packet handler
  * @ci: UDC descriptor
  *
- * This function handles traffic events
+ * This function handles setup packet 
  */
-static void isr_tr_complete_handler(struct ci_hdrc *ci)
+static void isr_setup_packet_handler(struct ci_hdrc *ci)
 __releases(ci->lock)
 __acquires(ci->lock)
 {
-	unsigned i;
-	u8 tmode = 0;
-
-	for (i = 0; i < ci->hw_ep_max; i++) {
-		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
-		int type, num, dir, err = -EINVAL;
+	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
 	struct usb_ctrlrequest req;
-
-		if (hwep->ep.desc == NULL)
-			continue;   /* not configured */
-
-		if (hw_test_and_clear_complete(ci, i)) {
-			err = isr_tr_complete_low(hwep);
-			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
-				if (err > 0)   /* needs status phase */
-					err = isr_setup_status_phase(ci);
-				if (err < 0) {
-					spin_unlock(&ci->lock);
-					if (usb_ep_set_halt(&hwep->ep))
-						dev_err(ci->dev,
-							"error: ep_set_halt\n");
-					spin_lock(&ci->lock);
-				}
-			}
-		}
-
-		/* Only handle setup packet below */
-		if (i != 0 ||
-			!hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
-			continue;
+	int type, num, dir, err = -EINVAL;
+	u8 tmode = 0;
 
 	/*
 	 * Flush data and handshake transactions of previous
@@ -1017,7 +991,7 @@ __acquires(ci->lock)
 			dir = num & USB_ENDPOINT_DIR_MASK;
 			num &= USB_ENDPOINT_NUMBER_MASK;
 			if (dir) /* TX */
-					num += ci->hw_ep_max/2;
+				num += ci->hw_ep_max / 2;
 			if (!ci->ci_hw_ep[num].wedge) {
 				spin_unlock(&ci->lock);
 				err = usb_ep_clear_halt(
@@ -1068,7 +1042,7 @@ __acquires(ci->lock)
 			dir = num & USB_ENDPOINT_DIR_MASK;
 			num &= USB_ENDPOINT_NUMBER_MASK;
 			if (dir) /* TX */
-					num += ci->hw_ep_max/2;
+				num += ci->hw_ep_max / 2;
 
 			spin_unlock(&ci->lock);
 			err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
@@ -1122,6 +1096,46 @@ __acquires(ci->lock)
 			dev_err(ci->dev, "error: ep_set_halt\n");
 		spin_lock(&ci->lock);
 	}
+}
+
+/**
+ * isr_tr_complete_handler: transaction complete interrupt handler
+ * @ci: UDC descriptor
+ *
+ * This function handles traffic events
+ */
+static void isr_tr_complete_handler(struct ci_hdrc *ci)
+__releases(ci->lock)
+__acquires(ci->lock)
+{
+	unsigned i;
+	int err;
+
+	for (i = 0; i < ci->hw_ep_max; i++) {
+		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
+
+		if (hwep->ep.desc == NULL)
+			continue;   /* not configured */
+
+		if (hw_test_and_clear_complete(ci, i)) {
+			err = isr_tr_complete_low(hwep);
+			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
+				if (err > 0)   /* needs status phase */
+					err = isr_setup_status_phase(ci);
+				if (err < 0) {
+					spin_unlock(&ci->lock);
+					if (usb_ep_set_halt(&hwep->ep))
+						dev_err(ci->dev,
+							"error: ep_set_halt\n");
+					spin_lock(&ci->lock);
+				}
+			}
+		}
+
+		/* Only handle setup packet below */
+		if (i == 0 &&
+			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
+			isr_setup_packet_handler(ci);
 	}
 }