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usb: gadget: fix eem_wrap cloned skb logic 

Even if the skb is cloned, we still need a ZLP or USB will stall.

Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
This commit is contained in:
Nathan Sullivan 2014-07-07 09:50:14 -05:00 committed by Felipe Balbi
parent 029d97ff54
commit d82aa8aeb0
1 changed files with 10 additions and 12 deletions
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22
drivers/usb/gadget/f_eem.c
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@ -355,20 +355,18 @@ static struct sk_buff *eem_wrap(struct gether *port, struct sk_buff *skb)
int padlen = 0;
u16 len = skb->len;
if (!skb_cloned(skb)) {
int headroom = skb_headroom(skb);
int tailroom = skb_tailroom(skb);
int headroom = skb_headroom(skb);
int tailroom = skb_tailroom(skb);
/* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0,
* stick two bytes of zero-length EEM packet on the end.
*/
if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0)
padlen += 2;
/* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0,
* stick two bytes of zero-length EEM packet on the end.
*/
if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0)
padlen += 2;
if ((tailroom >= (ETH_FCS_LEN + padlen)) &&
(headroom >= EEM_HLEN))
goto done;
}
if ((tailroom >= (ETH_FCS_LEN + padlen)) &&
(headroom >= EEM_HLEN) && !skb_cloned(skb))
goto done;
skb2 = skb_copy_expand(skb, EEM_HLEN, ETH_FCS_LEN + padlen, GFP_ATOMIC);
dev_kfree_skb_any(skb);