NFC: protect nci_data_exchange transactions

Protect 'cb' and 'cb_context' arguments in nci_data_exchange.
In fact, this implements a queue with max length of 1 data
exchange transactions in parallel.

Signed-off-by: Ilan Elias <ilane@ti.com>
Acked-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c
index 141790ada4aa..e5ed90fc1a9c 100644
--- a/net/nfc/nci/data.c
+++ b/net/nfc/nci/data.c
@@ -54,6 +54,8 @@ void nci_data_exchange_complete(struct nci_dev *ndev,
                 /* no waiting callback, free skb */
                 kfree_skb(skb);
         }
+
+        clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
 }
 
 /* ----------------- NCI TX Data ----------------- */