1 files changed, 44 insertions, 14 deletions

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 68834a2853c9..b70ded3760f2 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -60,7 +60,6 @@ EXPORT_SYMBOL_GPL(can_len2dlc);
 
 #ifdef CONFIG_CAN_CALC_BITTIMING
 #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
-#define CAN_CALC_SYNC_SEG 1
 
 /* Bit-timing calculation derived from:
  *
@@ -86,8 +85,8 @@ can_update_sample_point(const struct can_bittiming_const *btc,
 	int i;
 
 	for (i = 0; i <= 1; i++) {
-		tseg2 = tseg + CAN_CALC_SYNC_SEG -
-			(sample_point_nominal * (tseg + CAN_CALC_SYNC_SEG)) /
+		tseg2 = tseg + CAN_SYNC_SEG -
+			(sample_point_nominal * (tseg + CAN_SYNC_SEG)) /
 			1000 - i;
 		tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
 		tseg1 = tseg - tseg2;
@@ -96,8 +95,8 @@ can_update_sample_point(const struct can_bittiming_const *btc,
 			tseg2 = tseg - tseg1;
 		}
 
-		sample_point = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) /
-			(tseg + CAN_CALC_SYNC_SEG);
+		sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) /
+			(tseg + CAN_SYNC_SEG);
 		sample_point_error = abs(sample_point_nominal - sample_point);
 
 		if (sample_point <= sample_point_nominal &&
@@ -145,7 +144,7 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
 	/* tseg even = round down, odd = round up */
 	for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
 	     tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
-		tsegall = CAN_CALC_SYNC_SEG + tseg / 2;
+		tsegall = CAN_SYNC_SEG + tseg / 2;
 
 		/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
 		brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
@@ -223,7 +222,7 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
 
 	/* real bitrate */
 	bt->bitrate = priv->clock.freq /
-		(bt->brp * (CAN_CALC_SYNC_SEG + tseg1 + tseg2));
+		(bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2));
 
 	return 0;
 }
@@ -371,6 +370,28 @@ static int can_rx_state_to_frame(struct net_device *dev, enum can_state state)
 	}
 }
 
+static const char *can_get_state_str(const enum can_state state)
+{
+	switch (state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		return "Error Active";
+	case CAN_STATE_ERROR_WARNING:
+		return "Error Warning";
+	case CAN_STATE_ERROR_PASSIVE:
+		return "Error Passive";
+	case CAN_STATE_BUS_OFF:
+		return "Bus Off";
+	case CAN_STATE_STOPPED:
+		return "Stopped";
+	case CAN_STATE_SLEEPING:
+		return "Sleeping";
+	default:
+		return "<unknown>";
+	}
+
+	return "<unknown>";
+}
+
 void can_change_state(struct net_device *dev, struct can_frame *cf,
 		      enum can_state tx_state, enum can_state rx_state)
 {
@@ -382,7 +403,9 @@ void can_change_state(struct net_device *dev, struct can_frame *cf,
 		return;
 	}
 
-	netdev_dbg(dev, "New error state: %d\n", new_state);
+	netdev_dbg(dev, "Controller changed from %s State (%d) into %s State (%d).\n",
+		   can_get_state_str(priv->state), priv->state,
+		   can_get_state_str(new_state), new_state);
 
 	can_update_state_error_stats(dev, new_state);
 	priv->state = new_state;
@@ -434,8 +457,8 @@ static void can_flush_echo_skb(struct net_device *dev)
  * of the device driver. The driver must protect access to
  * priv->echo_skb, if necessary.
  */
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
-		      unsigned int idx)
+int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+		     unsigned int idx)
 {
 	struct can_priv *priv = netdev_priv(dev);
 
@@ -446,13 +469,13 @@ void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 	    (skb->protocol != htons(ETH_P_CAN) &&
 	     skb->protocol != htons(ETH_P_CANFD))) {
 		kfree_skb(skb);
-		return;
+		return 0;
 	}
 
 	if (!priv->echo_skb[idx]) {
 		skb = can_create_echo_skb(skb);
 		if (!skb)
-			return;
+			return -ENOMEM;
 
 		/* make settings for echo to reduce code in irq context */
 		skb->pkt_type = PACKET_BROADCAST;
@@ -463,9 +486,12 @@ void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 		priv->echo_skb[idx] = skb;
 	} else {
 		/* locking problem with netif_stop_queue() ?? */
-		netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__);
+		netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx);
 		kfree_skb(skb);
+		return -EBUSY;
 	}
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(can_put_echo_skb);
 
@@ -612,7 +638,11 @@ void can_bus_off(struct net_device *dev)
 {
 	struct can_priv *priv = netdev_priv(dev);
 
-	netdev_info(dev, "bus-off\n");
+	if (priv->restart_ms)
+		netdev_info(dev, "bus-off, scheduling restart in %d ms\n",
+			    priv->restart_ms);
+	else
+		netdev_info(dev, "bus-off\n");
 
 	netif_carrier_off(dev);