libertas: convert libertas driver to use an event/cmdresp queue

This patch (co-developed by Dan Williams and Holger Schurig) uses a kfifo
object for events and a swapping buffer scheme for the command response to
preserve the zero-copy semantics of the CF driver and keep memory usage low.
The main thread should only ever touch the buffer indexed by priv->resp_idx,
while the interface code is free to write to the second buffer, then swap
priv->resp_idx under the driver spinlock.  The firmware specs only permit
one in-flight command, so there will only ever be one command response to
process at a time.

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/net/wireless/libertas/rx.c b/drivers/net/wireless/libertas/rx.c
index 09f023089ea4..05af7316f698 100644
--- a/drivers/net/wireless/libertas/rx.c
+++ b/drivers/net/wireless/libertas/rx.c
@@ -145,14 +145,14 @@ int lbs_process_rxed_packet(struct lbs_private *priv, struct sk_buff *skb)
         struct net_device *dev = priv->dev;
         struct rxpackethdr *p_rx_pkt;
         struct rxpd *p_rx_pd;
-
         int hdrchop;
         struct ethhdr *p_ethhdr;
-
         const u8 rfc1042_eth_hdr[] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 
         lbs_deb_enter(LBS_DEB_RX);
 
+        BUG_ON(!skb);
+
         skb->ip_summed = CHECKSUM_NONE;
 
         if (priv->monitormode)