can: c_can: end pending transmission on network stop (ifdown)

commit 7ffd7b4e169d619e66928fe5d997723f2c6f1056 upstream.

Put controller into init mode in network stop to end pending transmissions. The
issue is observed in cases when transmitted frame is not acked.

Signed-off-by: Viktor Babrian <babrian.viktor@renyi.mta.hu>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
index 8e78bb48f5a4399f0fef7e991d64984c638c077a..60285820f7b401d3d4fc0e16fa4042a3476b32e6 100644 (file)
--- a/drivers/net/can/c_can/c_can.c
+++ b/drivers/net/can/c_can/c_can.c
@@ -611,6 +611,10 @@ static void c_can_stop(struct net_device *dev)
        struct c_can_priv *priv = netdev_priv(dev);
 
        c_can_irq_control(priv, false);
+
+       /* put ctrl to init on stop to end ongoing transmission */
+       priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_INIT);
+
        priv->can.state = CAN_STATE_STOPPED;
 }