1 files changed, 138 insertions, 16 deletions

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 8d6208c0b400..365a8cc62405 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -279,25 +279,45 @@ static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
 	return 0;
 }
 
+/* Checks the validity of predefined bitrate settings */
+static int can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,
+				const u32 *bitrate_const,
+				const unsigned int bitrate_const_cnt)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	unsigned int i;
+
+	for (i = 0; i < bitrate_const_cnt; i++) {
+		if (bt->bitrate == bitrate_const[i])
+			break;
+	}
+
+	if (i >= priv->bitrate_const_cnt)
+		return -EINVAL;
+
+	return 0;
+}
+
 static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
-			     const struct can_bittiming_const *btc)
+			     const struct can_bittiming_const *btc,
+			     const u32 *bitrate_const,
+			     const unsigned int bitrate_const_cnt)
 {
 	int err;
 
-	/* Check if the CAN device has bit-timing parameters */
-	if (!btc)
-		return -EOPNOTSUPP;
-
 	/*
 	 * Depending on the given can_bittiming parameter structure the CAN
 	 * timing parameters are calculated based on the provided bitrate OR
 	 * alternatively the CAN timing parameters (tq, prop_seg, etc.) are
 	 * provided directly which are then checked and fixed up.
 	 */
-	if (!bt->tq && bt->bitrate)
+	if (!bt->tq && bt->bitrate && btc)
 		err = can_calc_bittiming(dev, bt, btc);
-	else if (bt->tq && !bt->bitrate)
+	else if (bt->tq && !bt->bitrate && btc)
 		err = can_fixup_bittiming(dev, bt, btc);
+	else if (!bt->tq && bt->bitrate && bitrate_const)
+		err = can_validate_bitrate(dev, bt, bitrate_const,
+					   bitrate_const_cnt);
 	else
 		err = -EINVAL;
 
@@ -371,6 +391,9 @@ void can_change_state(struct net_device *dev, struct can_frame *cf,
 	can_update_state_error_stats(dev, new_state);
 	priv->state = new_state;
 
+	if (!cf)
+		return;
+
 	if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
 		cf->can_id |= CAN_ERR_BUSOFF;
 		return;
@@ -625,7 +648,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
 	can_skb_prv(skb)->ifindex = dev->ifindex;
 	can_skb_prv(skb)->skbcnt = 0;
 
-	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+	*cf = skb_put(skb, sizeof(struct can_frame));
 	memset(*cf, 0, sizeof(struct can_frame));
 
 	return skb;
@@ -654,7 +677,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 	can_skb_prv(skb)->ifindex = dev->ifindex;
 	can_skb_prv(skb)->skbcnt = 0;
 
-	*cfd = (struct canfd_frame *)skb_put(skb, sizeof(struct canfd_frame));
+	*cfd = skb_put(skb, sizeof(struct canfd_frame));
 	memset(*cfd, 0, sizeof(struct canfd_frame));
 
 	return skb;
@@ -825,7 +848,8 @@ static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
 				= { .len = sizeof(struct can_bittiming_const) },
 };
 
-static int can_validate(struct nlattr *tb[], struct nlattr *data[])
+static int can_validate(struct nlattr *tb[], struct nlattr *data[],
+			struct netlink_ext_ack *extack)
 {
 	bool is_can_fd = false;
 
@@ -857,8 +881,9 @@ static int can_validate(struct nlattr *tb[], struct nlattr *data[])
 	return 0;
 }
 
-static int can_changelink(struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[])
+static int can_changelink(struct net_device *dev, struct nlattr *tb[],
+			  struct nlattr *data[],
+			  struct netlink_ext_ack *extack)
 {
 	struct can_priv *priv = netdev_priv(dev);
 	int err;
@@ -872,8 +897,20 @@ static int can_changelink(struct net_device *dev,
 		/* Do not allow changing bittiming while running */
 		if (dev->flags & IFF_UP)
 			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->bittiming_const && !priv->do_set_bittiming)
+			return -EOPNOTSUPP;
+
 		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
-		err = can_get_bittiming(dev, &bt, priv->bittiming_const);
+		err = can_get_bittiming(dev, &bt,
+					priv->bittiming_const,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt);
 		if (err)
 			return err;
 		memcpy(&priv->bittiming, &bt, sizeof(bt));
@@ -943,9 +980,21 @@ static int can_changelink(struct net_device *dev,
 		/* Do not allow changing bittiming while running */
 		if (dev->flags & IFF_UP)
 			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * data_bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
+			return -EOPNOTSUPP;
+
 		memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
 		       sizeof(dbt));
-		err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
+		err = can_get_bittiming(dev, &dbt,
+					priv->data_bittiming_const,
+					priv->data_bitrate_const,
+					priv->data_bitrate_const_cnt);
 		if (err)
 			return err;
 		memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
@@ -958,6 +1007,30 @@ static int can_changelink(struct net_device *dev,
 		}
 	}
 
+	if (data[IFLA_CAN_TERMINATION]) {
+		const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
+		const unsigned int num_term = priv->termination_const_cnt;
+		unsigned int i;
+
+		if (!priv->do_set_termination)
+			return -EOPNOTSUPP;
+
+		/* check whether given value is supported by the interface */
+		for (i = 0; i < num_term; i++) {
+			if (termval == priv->termination_const[i])
+				break;
+		}
+		if (i >= num_term)
+			return -EINVAL;
+
+		/* Finally, set the termination value */
+		err = priv->do_set_termination(dev, termval);
+		if (err)
+			return err;
+
+		priv->termination = termval;
+	}
+
 	return 0;
 }
 
@@ -980,6 +1053,17 @@ static size_t can_get_size(const struct net_device *dev)
 		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));
+	if (priv->termination_const) {
+		size += nla_total_size(sizeof(priv->termination));		/* IFLA_CAN_TERMINATION */
+		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */
+				       priv->termination_const_cnt);
+	}
+	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */
+		size += nla_total_size(sizeof(*priv->bitrate_const) *
+				       priv->bitrate_const_cnt);
+	if (priv->data_bitrate_const)				/* IFLA_CAN_DATA_BITRATE_CONST */
+		size += nla_total_size(sizeof(*priv->data_bitrate_const) *
+				       priv->data_bitrate_const_cnt);
 
 	return size;
 }
@@ -1018,7 +1102,28 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	    (priv->data_bittiming_const &&
 	     nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
 		     sizeof(*priv->data_bittiming_const),
-		     priv->data_bittiming_const)))
+		     priv->data_bittiming_const)) ||
+
+	    (priv->termination_const &&
+	     (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
+	      nla_put(skb, IFLA_CAN_TERMINATION_CONST,
+		      sizeof(*priv->termination_const) *
+		      priv->termination_const_cnt,
+		      priv->termination_const))) ||
+
+	    (priv->bitrate_const &&
+	     nla_put(skb, IFLA_CAN_BITRATE_CONST,
+		     sizeof(*priv->bitrate_const) *
+		     priv->bitrate_const_cnt,
+		     priv->bitrate_const)) ||
+
+	    (priv->data_bitrate_const &&
+	     nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
+		     sizeof(*priv->data_bitrate_const) *
+		     priv->data_bitrate_const_cnt,
+		     priv->data_bitrate_const))
+	    )
+
 		return -EMSGSIZE;
 
 	return 0;
@@ -1043,7 +1148,8 @@ nla_put_failure:
 }
 
 static int can_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[])
+		       struct nlattr *tb[], struct nlattr *data[],
+		       struct netlink_ext_ack *extack)
 {
 	return -EOPNOTSUPP;
 }
@@ -1073,6 +1179,22 @@ static struct rtnl_link_ops can_link_ops __read_mostly = {
  */
 int register_candev(struct net_device *dev)
 {
+	struct can_priv *priv = netdev_priv(dev);
+
+	/* Ensure termination_const, termination_const_cnt and
+	 * do_set_termination consistency. All must be either set or
+	 * unset.
+	 */
+	if ((!priv->termination_const != !priv->termination_const_cnt) ||
+	    (!priv->termination_const != !priv->do_set_termination))
+		return -EINVAL;
+
+	if (!priv->bitrate_const != !priv->bitrate_const_cnt)
+		return -EINVAL;
+
+	if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt)
+		return -EINVAL;
+
 	dev->rtnl_link_ops = &can_link_ops;
 	return register_netdev(dev);
 }