USB: gadget: fix EEM gadget CRC usage

eem_wrap() is sending a sentinel CRC, but it didn't indicate that to
the host, it should zero bit 14 (bmCRC) in the EEM packet header,
instead of setting it.

Also remove a redundant crc calculation in eem_unwrap().

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

diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c
index 0a577d5..d4f0db5 100644 (file)
--- a/drivers/usb/gadget/f_eem.c
+++ b/drivers/usb/gadget/f_eem.c
@@ -358,7 +358,7 @@ done:
         * b15:         bmType (0 == data)
         */
        len = skb->len;
-       put_unaligned_le16((len & 0x3FFF) | BIT(14), skb_push(skb, 2));
+       put_unaligned_le16(len & 0x3FFF, skb_push(skb, 2));
 
        /* add a zero-length EEM packet, if needed */
        if (padlen)
@@ -464,7 +464,6 @@ static int eem_unwrap(struct gether *port,
                        }
 
                        /* validate CRC */
-                       crc = get_unaligned_le32(skb->data + len - ETH_FCS_LEN);
                        if (header & BIT(14)) {
                                crc = get_unaligned_le32(skb->data + len
                                                        - ETH_FCS_LEN);