cnic: Add a signature to indicate valid doorbell offset.

The buffer that is used to pass doorbell offset to the userspace UIO
driver may contain nonzero value in older versions of bnx2x driver.
Userspace cannot easily tell whether it contains a valid doorbell
offset or not.  With the added signature, userspace will only use
the doorbell offset if the signature is present.

Update version to 2.5.19.
Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/cnic.c

@@ -5220,6 +5220,7 @@ static void cnic_init_rings(struct cnic_dev *dev)
 		cnic_ring_ctl(dev, cid, cli, 1);
 		*cid_ptr = cid >> 4;
 		*(cid_ptr + 1) = cid * bp->db_size;
+		*(cid_ptr + 2) = UIO_USE_TX_DOORBELL;
 	}
 }
 

drivers/net/ethernet/broadcom/cnic.h

@@ -186,6 +186,8 @@ struct kcq_info {
 	u16		(*hw_idx)(u16);
 };
 
+#define UIO_USE_TX_DOORBELL 0x017855DB
+
 struct cnic_uio_dev {
 	struct uio_info		cnic_uinfo;
 	u32			uio_dev;

drivers/net/ethernet/broadcom/cnic_if.h

@@ -14,8 +14,8 @@
 
 #include "bnx2x/bnx2x_mfw_req.h"
 
-#define CNIC_MODULE_VERSION	"2.5.18"
-#define CNIC_MODULE_RELDATE	"Sept 01, 2013"
+#define CNIC_MODULE_VERSION	"2.5.19"
+#define CNIC_MODULE_RELDATE	"December 19, 2013"
 
 #define CNIC_ULP_RDMA		0
 #define CNIC_ULP_ISCSI		1