From 6f50d1c879bccb19c814d9f062b8f2e88f0e857c Mon Sep 17 00:00:00 2001
From: hwg <hwg@rock-chips.com>
Date: Sun, 9 Jun 2013 10:02:16 +0800
Subject: [PATCH] solve usb ethernet align problem: method form box

---
 drivers/net/usb/cdc_ether.c | 18 ------------------
 drivers/net/usb/usbnet.c    | 24 ++++++++++++++++++++++++
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index 5fe4f5bcf917..544c309e0d95 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -460,23 +460,6 @@ static int cdc_manage_power(struct usbnet *dev, int on)
 	return 0;
 }
 
-static struct sk_buff *android_tx_fixup(struct usbnet *dev,
-					struct sk_buff *skb,
-					gfp_t flags)
-{
-	struct sk_buff *tx_skb;
-
-	if ((unsigned long)skb->data % 4) {
-		tx_skb = alloc_skb(skb->len + NET_IP_ALIGN, flags);
-		if (tx_skb)
-			memcpy(skb_put(tx_skb, skb->len), skb->data, skb->len);
-		dev_kfree_skb_any(skb);
-	} else
-		tx_skb = skb;
-
-	return tx_skb;
-}
-
 static const struct driver_info	cdc_info = {
 	.description =	"CDC Ethernet Device",
 	.flags =	FLAG_ETHER | FLAG_POINTTOPOINT,
@@ -485,7 +468,6 @@ static const struct driver_info	cdc_info = {
 	.unbind =	usbnet_cdc_unbind,
 	.status =	usbnet_cdc_status,
 	.manage_power =	cdc_manage_power,
-        .tx_fixup =	android_tx_fixup,
 };
 
 static const struct driver_info wwan_info = {
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index d1ab1698e306..48c0cd144a2d 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1103,6 +1103,30 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
 			}
 		}
 	}
+	
+//$_rbox_$_modify_$_chenzhi
+//$_rbox_$_modify_$_begin
+/* data must be 4-byte aligned */
+        length = ((unsigned long)skb->data) & 0x3;
+        if (length) {
+                if (skb_cloned(skb) ||
+                    ((skb_headroom(skb) < length) &&
+                     (skb_tailroom(skb) < (4-length)))) {
+                        struct sk_buff *skb2;
+                        /* copy skb with proper alignment */
+                        skb2 = skb_copy_expand(skb, 0, 4, GFP_ATOMIC);
+                        dev_kfree_skb_any(skb);
+                        skb = skb2;
+                        if (!skb)
+                                goto drop;
+                } else {
+                        /* move data inside buffer */
+                        length = ((skb_headroom(skb) >= length) ? 0 : 4)-length;
+                        memmove(skb->data+length, skb->data, skb->len);
+                        skb_reserve(skb, length);
+                }
+        }
+//$_rbox_$_modify_$_end	
 	length = skb->len;
 
 	if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
-- 
2.34.1