can: add bittiming check at interface open for CAN FD

Additionally to have the second (data) bitrate available the data bitrate
has to be greater or equal to the arbitration bitrate in CAN FD.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 4e20d82b799e4e7b35d8b524af4ed748963faba9..c7a260478749ad163ec133df88e7a0086b220a73 100644 (file)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -642,6 +642,14 @@ int open_candev(struct net_device *dev)
                return -EINVAL;
        }
 
+       /* For CAN FD the data bitrate has to be >= the arbitration bitrate */
+       if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
+           (!priv->data_bittiming.bitrate ||
+            (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
+               netdev_err(dev, "incorrect/missing data bit-timing\n");
+               return -EINVAL;
+       }
+
        /* Switch carrier on if device was stopped while in bus-off state */
        if (!netif_carrier_ok(dev))
                netif_carrier_on(dev);