3 files changed, 50 insertions, 3 deletions

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 8141290e4c18..8ebe112458c4 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -647,6 +647,10 @@ static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
                                 = { .len = sizeof(struct can_bittiming_const) },
         [IFLA_CAN_CLOCK]        = { .len = sizeof(struct can_clock) },
         [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
+        [IFLA_CAN_DATA_BITTIMING]
+                                = { .len = sizeof(struct can_bittiming) },
+        [IFLA_CAN_DATA_BITTIMING_CONST]
+                                = { .len = sizeof(struct can_bittiming_const) },
 };
 
 static int can_changelink(struct net_device *dev,
@@ -707,6 +711,27 @@ static int can_changelink(struct net_device *dev,
                         return err;
         }
 
+        if (data[IFLA_CAN_DATA_BITTIMING]) {
+                struct can_bittiming dbt;
+
+                /* Do not allow changing bittiming while running */
+                if (dev->flags & IFF_UP)
+                        return -EBUSY;
+                memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
+                       sizeof(dbt));
+                err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
+                if (err)
+                        return err;
+                memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
+
+                if (priv->do_set_data_bittiming) {
+                        /* Finally, set the bit-timing registers */
+                        err = priv->do_set_data_bittiming(dev);
+                        if (err)
+                                return err;
+                }
+        }
+
         return 0;
 }
 
@@ -725,6 +750,10 @@ static size_t can_get_size(const struct net_device *dev)
         size += nla_total_size(sizeof(u32));                    /* IFLA_CAN_RESTART_MS */
         if (priv->do_get_berr_counter)                          /* IFLA_CAN_BERR_COUNTER */
                 size += nla_total_size(sizeof(struct can_berr_counter));
+        if (priv->data_bittiming.bitrate)                       /* IFLA_CAN_DATA_BITTIMING */
+                size += nla_total_size(sizeof(struct can_bittiming));
+        if (priv->data_bittiming_const)                         /* IFLA_CAN_DATA_BITTIMING_CONST */
+                size += nla_total_size(sizeof(struct can_bittiming_const));
 
         return size;
 }
@@ -738,20 +767,34 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 
         if (priv->do_get_state)
                 priv->do_get_state(dev, &state);
+
         if ((priv->bittiming.bitrate &&
              nla_put(skb, IFLA_CAN_BITTIMING,
                      sizeof(priv->bittiming), &priv->bittiming)) ||
+
             (priv->bittiming_const &&
              nla_put(skb, IFLA_CAN_BITTIMING_CONST,
                      sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
+
             nla_put(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock) ||
             nla_put_u32(skb, IFLA_CAN_STATE, state) ||
             nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
             nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
+
             (priv->do_get_berr_counter &&
              !priv->do_get_berr_counter(dev, &bec) &&
-             nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)))
+             nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
+
+            (priv->data_bittiming.bitrate &&
+             nla_put(skb, IFLA_CAN_DATA_BITTIMING,
+                     sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
+
+            (priv->data_bittiming_const &&
+             nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
+                     sizeof(*priv->data_bittiming_const),
+                     priv->data_bittiming_const)))
                 return -EMSGSIZE;
+
         return 0;
 }
 
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index dc5f9026b67f..8adaee96f292 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -33,8 +33,9 @@ enum can_mode {
 struct can_priv {
         struct can_device_stats can_stats;
 
-        struct can_bittiming bittiming;
-        const struct can_bittiming_const *bittiming_const;
+        struct can_bittiming bittiming, data_bittiming;
+        const struct can_bittiming_const *bittiming_const,
+                *data_bittiming_const;
         struct can_clock clock;
 
         enum can_state state;
@@ -45,6 +46,7 @@ struct can_priv {
         struct timer_list restart_timer;
 
         int (*do_set_bittiming)(struct net_device *dev);
+        int (*do_set_data_bittiming)(struct net_device *dev);
         int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
         int (*do_get_state)(const struct net_device *dev,
                             enum can_state *state);
diff --git a/include/uapi/linux/can/netlink.h b/include/uapi/linux/can/netlink.h
index df944ed206a8..b41933d6bdcd 100644
--- a/include/uapi/linux/can/netlink.h
+++ b/include/uapi/linux/can/netlink.h
@@ -122,6 +122,8 @@ enum {
         IFLA_CAN_RESTART_MS,
         IFLA_CAN_RESTART,
         IFLA_CAN_BERR_COUNTER,
+        IFLA_CAN_DATA_BITTIMING,
+        IFLA_CAN_DATA_BITTIMING_CONST,
         __IFLA_CAN_MAX
 };