Merge branch 'can-error-set-of-fixes-and-improvement-on-txerr-and-rxerr-reporting'

Vincent Mailhol says:

====================
can: error: set of fixes and improvement on txerr and rxerr reporting

This series is a collection of patches targeting the CAN error
counter. The series is split in three blocks (with small relation to
each other).

Several drivers uses the data[6] and data[7] fields (both of type u8)
of the CAN error frame to report those values. However, the maximum
size an u8 can hold is 255 and the error counter can exceed this value
if bus-off status occurs. As such, the first nine patches of this
series make sure that no drivers try to report txerr or rxerr through
the CAN error frame when bus-off status is reached.

can_frame::data[5..7] are defined as being "controller
specific". Controller specific behaviors are not something desirable
(portability issue...) The tenth patch of this series specifies how
can_frame::data[5..7] should be use and remove any "controller
specific" freedom. The eleventh patch adds a flag to notify though
can_frame::can_id that data[6..7] were populated (in order to be
consistent with other fields).

Finally, the twelfth and last patch add three macro values to specify
the different error counter threshold with so far was hard-coded as
magic numbers in the drivers.

N.B.:
  * patches 1 to 10 are for net (stable).
  * patches 11 and 12 are for net-next (but depends on patches 1 to 10).

** Changelog **

v1 -> v2: https://lore.kernel.org/all/20220712153157.83847-1-mailhol.vincent@wanadoo.fr
  * Fix typo in patch #10: data[7] of CAN error frames is for the RX
    error counter, not the TX one (this is litteraly a one byte
    change).
====================

As discussed take the whole series via can-next -> net-next.

Link: https://lore.kernel.org/all/20220719143550.3681-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

25 files changed, 94 insertions, 52 deletions

diff --git a/drivers/net/can/c_can/c_can_main.c b/drivers/net/can/c_can/c_can_main.c
index ed4db4cf87163..de38d8f7b5f7a 100644
--- a/drivers/net/can/c_can/c_can_main.c
+++ b/drivers/net/can/c_can/c_can_main.c
@@ -952,14 +952,14 @@ static int c_can_handle_state_change(struct net_device *dev,
 
 	switch (error_type) {
 	case C_CAN_NO_ERROR:
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = CAN_ERR_CRTL_ACTIVE;
 		cf->data[6] = bec.txerr;
 		cf->data[7] = bec.rxerr;
 		break;
 	case C_CAN_ERROR_WARNING:
 		/* error warning state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = (bec.txerr > bec.rxerr) ?
 			CAN_ERR_CRTL_TX_WARNING :
 			CAN_ERR_CRTL_RX_WARNING;
@@ -969,7 +969,7 @@ static int c_can_handle_state_change(struct net_device *dev,
 		break;
 	case C_CAN_ERROR_PASSIVE:
 		/* error passive state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		if (rx_err_passive)
 			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 		if (bec.txerr > 127)
diff --git a/drivers/net/can/cc770/cc770.c b/drivers/net/can/cc770/cc770.c
index bb7224cfc6ab5..797a954bb1a0c 100644
--- a/drivers/net/can/cc770/cc770.c
+++ b/drivers/net/can/cc770/cc770.c
@@ -512,6 +512,7 @@ static int cc770_err(struct net_device *dev, u8 status)
 
 	/* Use extended functions of the CC770 */
 	if (priv->control_normal_mode & CTRL_EAF) {
+		cf->can_id |= CAN_ERR_CNT;
 		cf->data[6] = cc770_read_reg(priv, tx_error_counter);
 		cf->data[7] = cc770_read_reg(priv, rx_error_counter);
 	}
diff --git a/drivers/net/can/ctucanfd/ctucanfd_base.c b/drivers/net/can/ctucanfd/ctucanfd_base.c
index 14ac7c0ee04ce..6b281f6eb9b41 100644
--- a/drivers/net/can/ctucanfd/ctucanfd_base.c
+++ b/drivers/net/can/ctucanfd/ctucanfd_base.c
@@ -847,7 +847,7 @@ static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
 		case CAN_STATE_ERROR_PASSIVE:
 			priv->can.can_stats.error_passive++;
 			if (skb) {
-				cf->can_id |= CAN_ERR_CRTL;
+				cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 				cf->data[1] = (bec.rxerr > 127) ?
 						CAN_ERR_CRTL_RX_PASSIVE :
 						CAN_ERR_CRTL_TX_PASSIVE;
@@ -858,7 +858,7 @@ static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
 		case CAN_STATE_ERROR_WARNING:
 			priv->can.can_stats.error_warning++;
 			if (skb) {
-				cf->can_id |= CAN_ERR_CRTL;
+				cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 				cf->data[1] |= (bec.txerr > bec.rxerr) ?
 					CAN_ERR_CRTL_TX_WARNING :
 					CAN_ERR_CRTL_RX_WARNING;
@@ -867,6 +867,7 @@ static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
 			}
 			break;
 		case CAN_STATE_ERROR_ACTIVE:
+			cf->can_id |= CAN_ERR_CNT;
 			cf->data[1] = CAN_ERR_CRTL_ACTIVE;
 			cf->data[6] = bec.txerr;
 			cf->data[7] = bec.rxerr;
diff --git a/drivers/net/can/grcan.c b/drivers/net/can/grcan.c
index 4c47c1055eff9..24035a6187c98 100644
--- a/drivers/net/can/grcan.c
+++ b/drivers/net/can/grcan.c
@@ -671,6 +671,7 @@ static void grcan_err(struct net_device *dev, u32 sources, u32 status)
 				/* There are no others at this point */
 				break;
 			}
+			cf.can_id |= CAN_ERR_CNT;
 			cf.data[6] = txerr;
 			cf.data[7] = rxerr;
 			priv->can.state = state;
diff --git a/drivers/net/can/ifi_canfd/ifi_canfd.c b/drivers/net/can/ifi_canfd/ifi_canfd.c
index 968ed6d7316bb..64e3be8b73af5 100644
--- a/drivers/net/can/ifi_canfd/ifi_canfd.c
+++ b/drivers/net/can/ifi_canfd/ifi_canfd.c
@@ -492,7 +492,7 @@ static int ifi_canfd_handle_state_change(struct net_device *ndev,
 	switch (new_state) {
 	case CAN_STATE_ERROR_WARNING:
 		/* error warning state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = (bec.txerr > bec.rxerr) ?
 			CAN_ERR_CRTL_TX_WARNING :
 			CAN_ERR_CRTL_RX_WARNING;
@@ -501,7 +501,7 @@ static int ifi_canfd_handle_state_change(struct net_device *ndev,
 		break;
 	case CAN_STATE_ERROR_PASSIVE:
 		/* error passive state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 		if (bec.txerr > 127)
 			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
diff --git a/drivers/net/can/janz-ican3.c b/drivers/net/can/janz-ican3.c
index 35bfb82d69299..ccb5c5405224e 100644
--- a/drivers/net/can/janz-ican3.c
+++ b/drivers/net/can/janz-ican3.c
@@ -1127,7 +1127,7 @@ static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
 	/* bus error interrupt */
 	if (isrc == CEVTIND_BEI) {
 		mod->can.can_stats.bus_error++;
-		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR | CAN_ERR_CNT;
 
 		switch (ecc & ECC_MASK) {
 		case ECC_BIT:
@@ -1153,7 +1153,7 @@ static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
 
 	if (state != mod->can.state && (state == CAN_STATE_ERROR_WARNING ||
 					state == CAN_STATE_ERROR_PASSIVE)) {
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		if (state == CAN_STATE_ERROR_WARNING) {
 			mod->can.can_stats.error_warning++;
 			cf->data[1] = (txerr > rxerr) ?
diff --git a/drivers/net/can/kvaser_pciefd.c b/drivers/net/can/kvaser_pciefd.c
index 017f2d36ffc38..dcd2c9d50d5e2 100644
--- a/drivers/net/can/kvaser_pciefd.c
+++ b/drivers/net/can/kvaser_pciefd.c
@@ -1306,7 +1306,7 @@ static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
 	shhwtstamps->hwtstamp =
 		ns_to_ktime(div_u64(p->timestamp * 1000,
 				    can->kv_pcie->freq_to_ticks_div));
-	cf->can_id |= CAN_ERR_BUSERROR;
+	cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT;
 
 	cf->data[6] = bec.txerr;
 	cf->data[7] = bec.rxerr;
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index afaaeb610c005..713a4b0edf860 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -741,7 +741,7 @@ static int m_can_handle_state_change(struct net_device *dev,
 	switch (new_state) {
 	case CAN_STATE_ERROR_WARNING:
 		/* error warning state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = (bec.txerr > bec.rxerr) ?
 			CAN_ERR_CRTL_TX_WARNING :
 			CAN_ERR_CRTL_RX_WARNING;
@@ -750,7 +750,7 @@ static int m_can_handle_state_change(struct net_device *dev,
 		break;
 	case CAN_STATE_ERROR_PASSIVE:
 		/* error passive state */
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		ecr = m_can_read(cdev, M_CAN_ECR);
 		if (ecr & ECR_RP)
 			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c
index fde3ac516d264..50f6719b3aa44 100644
--- a/drivers/net/can/pch_can.c
+++ b/drivers/net/can/pch_can.c
@@ -496,6 +496,10 @@ static void pch_can_error(struct net_device *ndev, u32 status)
 		cf->can_id |= CAN_ERR_BUSOFF;
 		priv->can.can_stats.bus_off++;
 		can_bus_off(ndev);
+	} else {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = errc & PCH_TEC;
+		cf->data[7] = (errc & PCH_REC) >> 8;
 	}
 
 	errc = ioread32(&priv->regs->errc);
@@ -556,9 +560,6 @@ static void pch_can_error(struct net_device *ndev, u32 status)
 		break;
 	}
 
-	cf->data[6] = errc & PCH_TEC;
-	cf->data[7] = (errc & PCH_REC) >> 8;
-
 	priv->can.state = state;
 	netif_receive_skb(skb);
 }
diff --git a/drivers/net/can/peak_canfd/peak_canfd.c b/drivers/net/can/peak_canfd/peak_canfd.c
index b2dea360813d2..afb9adb3d5c29 100644
--- a/drivers/net/can/peak_canfd/peak_canfd.c
+++ b/drivers/net/can/peak_canfd/peak_canfd.c
@@ -373,7 +373,7 @@ static int pucan_handle_status(struct peak_canfd_priv *priv,
 		priv->can.state = CAN_STATE_ERROR_PASSIVE;
 		priv->can.can_stats.error_passive++;
 		if (skb) {
-			cf->can_id |= CAN_ERR_CRTL;
+			cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 			cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
 					CAN_ERR_CRTL_TX_PASSIVE :
 					CAN_ERR_CRTL_RX_PASSIVE;
@@ -386,7 +386,7 @@ static int pucan_handle_status(struct peak_canfd_priv *priv,
 		priv->can.state = CAN_STATE_ERROR_WARNING;
 		priv->can.can_stats.error_warning++;
 		if (skb) {
-			cf->can_id |= CAN_ERR_CRTL;
+			cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 			cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
 					CAN_ERR_CRTL_TX_WARNING :
 					CAN_ERR_CRTL_RX_WARNING;
@@ -430,7 +430,7 @@ static int pucan_handle_cache_critical(struct peak_canfd_priv *priv)
 		return -ENOMEM;
 	}
 
-	cf->can_id |= CAN_ERR_CRTL;
+	cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 
 	cf->data[6] = priv->bec.txerr;
diff --git a/drivers/net/can/rcar/rcar_can.c b/drivers/net/can/rcar/rcar_can.c
index d45762f1cf6bc..d11db2112a4a7 100644
--- a/drivers/net/can/rcar/rcar_can.c
+++ b/drivers/net/can/rcar/rcar_can.c
@@ -232,11 +232,8 @@ static void rcar_can_error(struct net_device *ndev)
 	if (eifr & (RCAR_CAN_EIFR_EWIF | RCAR_CAN_EIFR_EPIF)) {
 		txerr = readb(&priv->regs->tecr);
 		rxerr = readb(&priv->regs->recr);
-		if (skb) {
+		if (skb)
 			cf->can_id |= CAN_ERR_CRTL;
-			cf->data[6] = txerr;
-			cf->data[7] = rxerr;
-		}
 	}
 	if (eifr & RCAR_CAN_EIFR_BEIF) {
 		int rx_errors = 0, tx_errors = 0;
@@ -336,6 +333,10 @@ static void rcar_can_error(struct net_device *ndev)
 		can_bus_off(ndev);
 		if (skb)
 			cf->can_id |= CAN_ERR_BUSOFF;
+	} else if (skb) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
 	}
 	if (eifr & RCAR_CAN_EIFR_ORIF) {
 		netdev_dbg(priv->ndev, "Receive overrun error interrupt\n");
diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index ba42cef10a532..e3382284e172e 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -1052,7 +1052,7 @@ static void rcar_canfd_error(struct net_device *ndev, u32 cerfl,
 		netdev_dbg(ndev, "Error warning interrupt\n");
 		priv->can.state = CAN_STATE_ERROR_WARNING;
 		priv->can.can_stats.error_warning++;
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_WARNING :
 			CAN_ERR_CRTL_RX_WARNING;
 		cf->data[6] = txerr;
@@ -1062,7 +1062,7 @@ static void rcar_canfd_error(struct net_device *ndev, u32 cerfl,
 		netdev_dbg(ndev, "Error passive interrupt\n");
 		priv->can.state = CAN_STATE_ERROR_PASSIVE;
 		priv->can.can_stats.error_passive++;
-		cf->can_id |= CAN_ERR_CRTL;
+		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
 		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_PASSIVE :
 			CAN_ERR_CRTL_RX_PASSIVE;
 		cf->data[6] = txerr;
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
index d9da471f1bb91..75a2f9bf8c16b 100644
--- a/drivers/net/can/sja1000/sja1000.c
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -404,9 +404,6 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 	txerr = priv->read_reg(priv, SJA1000_TXERR);
 	rxerr = priv->read_reg(priv, SJA1000_RXERR);
 
-	cf->data[6] = txerr;
-	cf->data[7] = rxerr;
-
 	if (isrc & IRQ_DOI) {
 		/* data overrun interrupt */
 		netdev_dbg(dev, "data overrun interrupt\n");
@@ -428,6 +425,11 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 		else
 			state = CAN_STATE_ERROR_ACTIVE;
 	}
+	if (state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
 	if (isrc & IRQ_BEI) {
 		/* bus error interrupt */
 		priv->can.can_stats.bus_error++;
diff --git a/drivers/net/can/slcan/slcan-core.c b/drivers/net/can/slcan/slcan-core.c
index 057b211f3e7f4..dc28e715bbe17 100644
--- a/drivers/net/can/slcan/slcan-core.c
+++ b/drivers/net/can/slcan/slcan-core.c
@@ -306,19 +306,18 @@ static void slc_bump_state(struct slcan *sl)
 		return;
 
 	skb = alloc_can_err_skb(dev, &cf);
-	if (skb) {
-		cf->data[6] = txerr;
-		cf->data[7] = rxerr;
-	} else {
-		cf = NULL;
-	}
 
 	tx_state = txerr >= rxerr ? state : 0;
 	rx_state = txerr <= rxerr ? state : 0;
 	can_change_state(dev, cf, tx_state, rx_state);
 
-	if (state == CAN_STATE_BUS_OFF)
+	if (state == CAN_STATE_BUS_OFF) {
 		can_bus_off(dev);
+	} else if (skb) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
 
 	if (skb)
 		netif_rx(skb);
diff --git a/drivers/net/can/spi/hi311x.c b/drivers/net/can/spi/hi311x.c
index ebc4ebb44c980..167114aae6dd1 100644
--- a/drivers/net/can/spi/hi311x.c
+++ b/drivers/net/can/spi/hi311x.c
@@ -667,8 +667,6 @@ static irqreturn_t hi3110_can_ist(int irq, void *dev_id)
 
 			txerr = hi3110_read(spi, HI3110_READ_TEC);
 			rxerr = hi3110_read(spi, HI3110_READ_REC);
-			cf->data[6] = txerr;
-			cf->data[7] = rxerr;
 			tx_state = txerr >= rxerr ? new_state : 0;
 			rx_state = txerr <= rxerr ? new_state : 0;
 			can_change_state(net, cf, tx_state, rx_state);
@@ -681,6 +679,10 @@ static irqreturn_t hi3110_can_ist(int irq, void *dev_id)
 					hi3110_hw_sleep(spi);
 					break;
 				}
+			} else {
+				cf->can_id |= CAN_ERR_CNT;
+				cf->data[6] = txerr;
+				cf->data[7] = rxerr;
 			}
 		}
 
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
index 9b47b07162fe5..f4e174cadd4ef 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -1099,6 +1099,7 @@ static int mcp251xfd_handle_cerrif(struct mcp251xfd_priv *priv)
 		err = mcp251xfd_get_berr_counter(priv->ndev, &bec);
 		if (err)
 			return err;
+		cf->can_id |= CAN_ERR_CNT;
 		cf->data[6] = bec.txerr;
 		cf->data[7] = bec.rxerr;
 	}
diff --git a/drivers/net/can/sun4i_can.c b/drivers/net/can/sun4i_can.c
index 155b90f6c767c..b90dfb429ccdc 100644
--- a/drivers/net/can/sun4i_can.c
+++ b/drivers/net/can/sun4i_can.c
@@ -535,11 +535,6 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 	rxerr = (errc >> 16) & 0xFF;
 	txerr = errc & 0xFF;
 
-	if (skb) {
-		cf->data[6] = txerr;
-		cf->data[7] = rxerr;
-	}
-
 	if (isrc & SUN4I_INT_DATA_OR) {
 		/* data overrun interrupt */
 		netdev_dbg(dev, "data overrun interrupt\n");
@@ -570,6 +565,11 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		else
 			state = CAN_STATE_ERROR_ACTIVE;
 	}
+	if (skb && state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
 	if (isrc & SUN4I_INT_BUS_ERR) {
 		/* bus error interrupt */
 		netdev_dbg(dev, "bus error interrupt\n");
diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index debe17bfd0f0e..afa38771520eb 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c
@@ -662,6 +662,7 @@ static void ti_hecc_change_state(struct net_device *ndev,
 	can_change_state(priv->ndev, cf, tx_state, rx_state);
 
 	if (max(tx_state, rx_state) != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
 		cf->data[6] = hecc_read(priv, HECC_CANTEC);
 		cf->data[7] = hecc_read(priv, HECC_CANREC);
 	}
diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 8a4bf2961f3d8..177ed33e08d9e 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -265,7 +265,8 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 			priv->can.can_stats.bus_error++;
 			stats->rx_errors++;
 
-			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR |
+				      CAN_ERR_CNT;
 
 			switch (ecc & SJA1000_ECC_MASK) {
 			case SJA1000_ECC_BIT:
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
index 5d70844ac0300..dd65c101bfb8e 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
@@ -917,8 +917,11 @@ static void kvaser_usb_hydra_update_state(struct kvaser_usb_net_priv *priv,
 	    new_state < CAN_STATE_BUS_OFF)
 		priv->can.can_stats.restarts++;
 
-	cf->data[6] = bec->txerr;
-	cf->data[7] = bec->rxerr;
+	if (new_state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = bec->txerr;
+		cf->data[7] = bec->rxerr;
+	}
 
 	netif_rx(skb);
 }
@@ -1069,8 +1072,11 @@ kvaser_usb_hydra_error_frame(struct kvaser_usb_net_priv *priv,
 	shhwtstamps->hwtstamp = hwtstamp;
 
 	cf->can_id |= CAN_ERR_BUSERROR;
-	cf->data[6] = bec.txerr;
-	cf->data[7] = bec.rxerr;
+	if (new_state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = bec.txerr;
+		cf->data[7] = bec.rxerr;
+	}
 
 	netif_rx(skb);
 
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
index cc809ecd1e622..07f687f29b341 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
@@ -853,8 +853,11 @@ static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev,
 		break;
 	}
 
-	cf->data[6] = es->txerr;
-	cf->data[7] = es->rxerr;
+	if (new_state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = es->txerr;
+		cf->data[7] = es->rxerr;
+	}
 
 	netif_rx(skb);
 }
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb.c b/drivers/net/can/usb/peak_usb/pcan_usb.c
index 091c631ebe235..d07b7ee79e3e4 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb.c
@@ -506,6 +506,7 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
 			/* Supply TX/RX error counters in case of
 			 * controller error.
 			 */
+			cf->can_id = CAN_ERR_CNT;
 			cf->data[6] = mc->pdev->bec.txerr;
 			cf->data[7] = mc->pdev->bec.rxerr;
 		}
diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c
index f3363575bf32c..8b7cd69e20b04 100644
--- a/drivers/net/can/usb/usb_8dev.c
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -438,9 +438,11 @@ static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv,
 
 	if (rx_errors)
 		stats->rx_errors++;
-
-	cf->data[6] = txerr;
-	cf->data[7] = rxerr;
+	if (priv->can.state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
 
 	priv->bec.txerr = txerr;
 	priv->bec.rxerr = rxerr;
diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 0de2f97d9f62f..caa6b4cee63f2 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -965,6 +965,7 @@ static void xcan_set_error_state(struct net_device *ndev,
 	can_change_state(ndev, cf, tx_state, rx_state);
 
 	if (cf) {
+		cf->can_id |= CAN_ERR_CNT;
 		cf->data[6] = txerr;
 		cf->data[7] = rxerr;
 	}
diff --git a/include/uapi/linux/can/error.h b/include/uapi/linux/can/error.h
index 34633283de641..acc1ac393d2a1 100644
--- a/include/uapi/linux/can/error.h
+++ b/include/uapi/linux/can/error.h
@@ -57,6 +57,8 @@
 #define CAN_ERR_BUSOFF       0x00000040U /* bus off */
 #define CAN_ERR_BUSERROR     0x00000080U /* bus error (may flood!) */
 #define CAN_ERR_RESTARTED    0x00000100U /* controller restarted */
+#define CAN_ERR_CNT          0x00000200U /* TX error counter / data[6] */
+					 /* RX error counter / data[7] */
 
 /* arbitration lost in bit ... / data[0] */
 #define CAN_ERR_LOSTARB_UNSPEC   0x00 /* unspecified */
@@ -120,6 +122,22 @@
 #define CAN_ERR_TRX_CANL_SHORT_TO_GND  0x70 /* 0111 0000 */
 #define CAN_ERR_TRX_CANL_SHORT_TO_CANH 0x80 /* 1000 0000 */
 
-/* controller specific additional information / data[5..7] */
+/* data[5] is reserved (do not use) */
+
+/* TX error counter / data[6] */
+/* RX error counter / data[7] */
+
+/* CAN state thresholds
+ *
+ * Error counter	Error state
+ * -----------------------------------
+ * 0 -  95		Error-active
+ * 96 - 127		Error-warning
+ * 128 - 255		Error-passive
+ * 256 and greater	Bus-off
+ */
+#define CAN_ERROR_WARNING_THRESHOLD 96
+#define CAN_ERROR_PASSIVE_THRESHOLD 128
+#define CAN_BUS_OFF_THRESHOLD 256
 
 #endif /* _UAPI_CAN_ERROR_H */