solve usb buffer align problem to support usb tether(rndis)

diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c
index 51d572eae9ad8c09c50cb826a22b7a865f1a4e4d..273718441c382580b39fa5a963bdd7227a68e4fc 100644 (file)
--- a/drivers/usb/gadget/u_ether.c
+++ b/drivers/usb/gadget/u_ether.c
@@ -31,6 +31,7 @@
 
 #include "u_ether.h"
 
+static gfp_t g_gfp_flags;
 
 /*
  * This component encapsulates the Ethernet link glue needed to provide
@@ -253,7 +254,7 @@ rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
         * but on at least one, checksumming fails otherwise.  Note:
         * RNDIS headers involve variable numbers of LE32 values.
         */
-       skb_reserve(skb, NET_IP_ALIGN);
+       //skb_reserve(skb, NET_IP_ALIGN);
 
        req->buf = skb->data;
        req->length = size;
@@ -577,6 +578,21 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
 
                length = skb->len;
        }
+       
+       // for tx fixup
+       {
+               struct sk_buff *tx_skb;
+               if ((unsigned long)skb->data % 4) {
+                       tx_skb = alloc_skb(skb->len + NET_IP_ALIGN, g_gfp_flags);
+                       if (tx_skb)
+                               memcpy(skb_put(tx_skb, skb->len), skb->data, skb->len);
+                       dev_kfree_skb_any(skb);
+                       skb = tx_skb;
+               }
+               length = skb->len;
+       }       
+       // for tx fixup
+       
        req->buf = skb->data;
        req->context = skb;
        req->complete = tx_complete;
@@ -632,6 +648,8 @@ drop:
 static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
 {
        DBG(dev, "%s\n", __func__);
+       
+       g_gfp_flags = gfp_flags;
 
        /* fill the rx queue */
        rx_fill(dev, gfp_flags);