IB/mthca: Don't read reserved fields in mthca_QUERY_ADAPTER()

For memfree devices, the firmware QUERY_ADAPTER command does not
return vendor_id, device_id, and revision_id; do not return these
fields in the QUERY_ADAPTER function for memfree devices.

Instead, for memfree devices, initialize the rev_id field of the mthca
device via init_node_data (MAD IFC query), as is done in the
query_device verb implementation.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 19b7f61..9e491df 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -1256,6 +1256,8 @@
 		goto out;
 	}
 
+	if (mthca_is_memfree(dev))
+		dev->rev_id = be32_to_cpup((__be32 *) (out_mad->data + 32));
 	memcpy(&dev->ib_dev.node_guid, out_mad->data + 12, 8);
 
 out: