sierra_net: Skip validating irrelevant fields for IDLE LSIs

BugLink: http://bugs.launchpad.net/bugs/1698817

[ Upstream commit 764895d3 ]

When the context is deactivated, the link_type is set to 0xff, which
triggers a warning message, and results in a wrong link status, as
the LSI is ignored.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

drivers/net/usb/sierra_net.c

@@ -365,6 +365,13 @@ static int sierra_net_parse_lsi(struct usbnet *dev, char *data, int datalen)
 		return -1;
 	}
 
+	/* Validate the session state */
+	if (lsi->session_state == SIERRA_NET_SESSION_IDLE) {
+		netdev_err(dev->net, "Session idle, 0x%02x\n",
+			   lsi->session_state);
+		return 0;
+	}
+
 	/* Validate the protocol  - only support UMTS for now */
 	if (lsi->protocol != SIERRA_NET_PROTOCOL_UMTS) {
 		netdev_err(dev->net, "Protocol unsupported, 0x%02x\n",
@@ -386,13 +393,6 @@ static int sierra_net_parse_lsi(struct usbnet *dev, char *data, int datalen)
 		return 0;
 	}
 
-	/* Validate the session state */
-	if (lsi->session_state == SIERRA_NET_SESSION_IDLE) {
-		netdev_err(dev->net, "Session idle, 0x%02x\n",
-			lsi->session_state);
-		return 0;
-	}
-
 	/* Set link_sense true */
 	return 1;
 }