USB: gadget: Add EEM gadget driver

This patch adds a CDC EEM ethernet gadget driver.  CDC EEM is a newer
USB ethernet specification that uses a simpler interface than the older
CDC ECM.  This makes CDC EEM usable by a wider set of USB hardware.
By default the ethernet gadget will still use CDC ECM/Subset, but kernel
configuration and/or a module parameter will allow alternative use of
the CDC EEM protocol.

Changes since last version:
	- Brought in missing RNDIS changes that caused compile error
	- Modified 'sentinel CRC' checking to match EEM host driver

Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/usb/gadget/rndis.c b/drivers/usb/gadget/rndis.c
index ca41b0b5afb..48267bc0b2e 100644
--- a/drivers/usb/gadget/rndis.c
+++ b/drivers/usb/gadget/rndis.c
@@ -1022,22 +1022,29 @@ static rndis_resp_t *rndis_add_response (int configNr, u32 length)
 	return r;
 }
 
-int rndis_rm_hdr(struct sk_buff *skb)
+int rndis_rm_hdr(struct gether *port,
+			struct sk_buff *skb,
+			struct sk_buff_head *list)
 {
 	/* tmp points to a struct rndis_packet_msg_type */
 	__le32		*tmp = (void *) skb->data;
 
 	/* MessageType, MessageLength */
 	if (cpu_to_le32(REMOTE_NDIS_PACKET_MSG)
-			!= get_unaligned(tmp++))
+			!= get_unaligned(tmp++)) {
+		dev_kfree_skb_any(skb);
 		return -EINVAL;
+	}
 	tmp++;
 
 	/* DataOffset, DataLength */
-	if (!skb_pull(skb, get_unaligned_le32(tmp++) + 8))
+	if (!skb_pull(skb, get_unaligned_le32(tmp++) + 8)) {
+		dev_kfree_skb_any(skb);
 		return -EOVERFLOW;
+	}
 	skb_trim(skb, get_unaligned_le32(tmp++));
 
+	skb_queue_tail(list, skb);
 	return 0;
 }