1 files changed, 98 insertions, 130 deletions

diff --git a/drivers/net/can/usb/peak_usb/pcan_usb.c b/drivers/net/can/usb/peak_usb/pcan_usb.c
index 899a3d21b77f..837b3fecd71e 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb.c
@@ -63,6 +63,8 @@
 
 #define PCAN_USB_MSG_HEADER_LEN		2
 
+#define PCAN_USB_MSG_TX_CAN		2	/* Tx msg is a CAN frame */
+
 /* PCAN-USB adapter internal clock (MHz) */
 #define PCAN_USB_CRYSTAL_HZ		16000000
 
@@ -73,6 +75,10 @@
 #define PCAN_USB_STATUSLEN_RTR		(1 << 4)
 #define PCAN_USB_STATUSLEN_DLC		(0xf)
 
+/* PCAN-USB 4.1 CAN Id tx extended flags */
+#define PCAN_USB_TX_SRR			0x01	/* SJA1000 SRR command */
+#define PCAN_USB_TX_AT			0x02	/* SJA1000 AT command */
+
 /* PCAN-USB error flags */
 #define PCAN_USB_ERROR_TXFULL		0x01
 #define PCAN_USB_ERROR_RXQOVR		0x02
@@ -385,7 +391,8 @@ static int pcan_usb_get_device_id(struct peak_usb_device *dev, u32 *device_id)
 	if (err)
 		netdev_err(dev->netdev, "getting device id failure: %d\n", err);
 
-	*device_id = args[0];
+	else
+		*device_id = args[0];
 
 	return err;
 }
@@ -446,145 +453,65 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
 {
 	struct sk_buff *skb;
 	struct can_frame *cf;
-	enum can_state new_state;
+	enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
 
 	/* ignore this error until 1st ts received */
 	if (n == PCAN_USB_ERROR_QOVR)
 		if (!mc->pdev->time_ref.tick_count)
 			return 0;
 
-	new_state = mc->pdev->dev.can.state;
-
-	switch (mc->pdev->dev.can.state) {
-	case CAN_STATE_ERROR_ACTIVE:
-		if (n & PCAN_USB_ERROR_BUS_LIGHT) {
-			new_state = CAN_STATE_ERROR_WARNING;
-			break;
-		}
-		fallthrough;
-
-	case CAN_STATE_ERROR_WARNING:
-		if (n & PCAN_USB_ERROR_BUS_HEAVY) {
-			new_state = CAN_STATE_ERROR_PASSIVE;
-			break;
-		}
-		if (n & PCAN_USB_ERROR_BUS_OFF) {
-			new_state = CAN_STATE_BUS_OFF;
-			break;
-		}
-		if (n & ~PCAN_USB_ERROR_BUS) {
-			/*
-			 * trick to bypass next comparison and process other
-			 * errors
-			 */
-			new_state = CAN_STATE_MAX;
-			break;
-		}
-		if ((n & PCAN_USB_ERROR_BUS_LIGHT) == 0) {
-			/* no error (back to active state) */
-			new_state = CAN_STATE_ERROR_ACTIVE;
-			break;
-		}
-		break;
-
-	case CAN_STATE_ERROR_PASSIVE:
-		if (n & PCAN_USB_ERROR_BUS_OFF) {
-			new_state = CAN_STATE_BUS_OFF;
-			break;
-		}
-		if (n & PCAN_USB_ERROR_BUS_LIGHT) {
-			new_state = CAN_STATE_ERROR_WARNING;
-			break;
-		}
-		if (n & ~PCAN_USB_ERROR_BUS) {
-			/*
-			 * trick to bypass next comparison and process other
-			 * errors
-			 */
-			new_state = CAN_STATE_MAX;
-			break;
-		}
-
-		if ((n & PCAN_USB_ERROR_BUS_HEAVY) == 0) {
-			/* no error (back to warning state) */
-			new_state = CAN_STATE_ERROR_WARNING;
-			break;
-		}
-		break;
-
-	default:
-		/* do nothing waiting for restart */
-		return 0;
-	}
-
-	/* donot post any error if current state didn't change */
-	if (mc->pdev->dev.can.state == new_state)
-		return 0;
-
 	/* allocate an skb to store the error frame */
 	skb = alloc_can_err_skb(mc->netdev, &cf);
-	if (!skb)
-		return -ENOMEM;
-
-	switch (new_state) {
-	case CAN_STATE_BUS_OFF:
-		cf->can_id |= CAN_ERR_BUSOFF;
-		mc->pdev->dev.can.can_stats.bus_off++;
-		can_bus_off(mc->netdev);
-		break;
-
-	case CAN_STATE_ERROR_PASSIVE:
-		cf->can_id |= CAN_ERR_CRTL;
-		cf->data[1] = (mc->pdev->bec.txerr > mc->pdev->bec.rxerr) ?
-				CAN_ERR_CRTL_TX_PASSIVE :
-				CAN_ERR_CRTL_RX_PASSIVE;
-		cf->data[6] = mc->pdev->bec.txerr;
-		cf->data[7] = mc->pdev->bec.rxerr;
-
-		mc->pdev->dev.can.can_stats.error_passive++;
-		break;
-
-	case CAN_STATE_ERROR_WARNING:
-		cf->can_id |= CAN_ERR_CRTL;
-		cf->data[1] = (mc->pdev->bec.txerr > mc->pdev->bec.rxerr) ?
-				CAN_ERR_CRTL_TX_WARNING :
-				CAN_ERR_CRTL_RX_WARNING;
-		cf->data[6] = mc->pdev->bec.txerr;
-		cf->data[7] = mc->pdev->bec.rxerr;
-
-		mc->pdev->dev.can.can_stats.error_warning++;
-		break;
 
-	case CAN_STATE_ERROR_ACTIVE:
-		cf->can_id |= CAN_ERR_CRTL;
-		cf->data[1] = CAN_ERR_CRTL_ACTIVE;
-
-		/* sync local copies of rxerr/txerr counters */
-		mc->pdev->bec.txerr = 0;
-		mc->pdev->bec.rxerr = 0;
-		break;
-
-	default:
-		/* CAN_STATE_MAX (trick to handle other errors) */
-		if (n & PCAN_USB_ERROR_TXQFULL)
-			netdev_dbg(mc->netdev, "device Tx queue full)\n");
-
-		if (n & PCAN_USB_ERROR_RXQOVR) {
-			netdev_dbg(mc->netdev, "data overrun interrupt\n");
+	if (n & PCAN_USB_ERROR_RXQOVR) {
+		/* data overrun interrupt */
+		netdev_dbg(mc->netdev, "data overrun interrupt\n");
+		mc->netdev->stats.rx_over_errors++;
+		mc->netdev->stats.rx_errors++;
+		if (cf) {
 			cf->can_id |= CAN_ERR_CRTL;
 			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
-			mc->netdev->stats.rx_over_errors++;
-			mc->netdev->stats.rx_errors++;
 		}
+	}
 
-		cf->data[6] = mc->pdev->bec.txerr;
-		cf->data[7] = mc->pdev->bec.rxerr;
+	if (n & PCAN_USB_ERROR_TXQFULL)
+		netdev_dbg(mc->netdev, "device Tx queue full)\n");
 
-		new_state = mc->pdev->dev.can.state;
-		break;
+	if (n & PCAN_USB_ERROR_BUS_OFF) {
+		new_state = CAN_STATE_BUS_OFF;
+	} else if (n & PCAN_USB_ERROR_BUS_HEAVY) {
+		new_state = ((mc->pdev->bec.txerr >= 128) ||
+			     (mc->pdev->bec.rxerr >= 128)) ?
+				CAN_STATE_ERROR_PASSIVE :
+				CAN_STATE_ERROR_WARNING;
+	} else {
+		new_state = CAN_STATE_ERROR_ACTIVE;
 	}
 
-	mc->pdev->dev.can.state = new_state;
+	/* handle change of state */
+	if (new_state != mc->pdev->dev.can.state) {
+		enum can_state tx_state =
+			(mc->pdev->bec.txerr >= mc->pdev->bec.rxerr) ?
+				new_state : 0;
+		enum can_state rx_state =
+			(mc->pdev->bec.txerr <= mc->pdev->bec.rxerr) ?
+				new_state : 0;
+
+		can_change_state(mc->netdev, cf, tx_state, rx_state);
+
+		if (new_state == CAN_STATE_BUS_OFF) {
+			can_bus_off(mc->netdev);
+		} else if (cf && (cf->can_id & CAN_ERR_CRTL)) {
+			/* Supply TX/RX error counters in case of
+			 * controller error.
+			 */
+			cf->data[6] = mc->pdev->bec.txerr;
+			cf->data[7] = mc->pdev->bec.rxerr;
+		}
+	}
+
+	if (!skb)
+		return -ENOMEM;
 
 	if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
 		struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
@@ -706,6 +633,7 @@ static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
 	struct sk_buff *skb;
 	struct can_frame *cf;
 	struct skb_shared_hwtstamps *hwts;
+	u32 can_id_flags;
 
 	skb = alloc_can_skb(mc->netdev, &cf);
 	if (!skb)
@@ -715,13 +643,15 @@ static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
 		if ((mc->ptr + 4) > mc->end)
 			goto decode_failed;
 
-		cf->can_id = get_unaligned_le32(mc->ptr) >> 3 | CAN_EFF_FLAG;
+		can_id_flags = get_unaligned_le32(mc->ptr);
+		cf->can_id = can_id_flags >> 3 | CAN_EFF_FLAG;
 		mc->ptr += 4;
 	} else {
 		if ((mc->ptr + 2) > mc->end)
 			goto decode_failed;
 
-		cf->can_id = get_unaligned_le16(mc->ptr) >> 5;
+		can_id_flags = get_unaligned_le16(mc->ptr);
+		cf->can_id = can_id_flags >> 5;
 		mc->ptr += 2;
 	}
 
@@ -744,6 +674,10 @@ static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
 
 		memcpy(cf->data, mc->ptr, cf->len);
 		mc->ptr += rec_len;
+
+		/* Ignore next byte (client private id) if SRR bit is set */
+		if (can_id_flags & PCAN_USB_TX_SRR)
+			mc->ptr++;
 	}
 
 	/* convert timestamp into kernel time */
@@ -821,10 +755,11 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
 	struct net_device *netdev = dev->netdev;
 	struct net_device_stats *stats = &netdev->stats;
 	struct can_frame *cf = (struct can_frame *)skb->data;
+	u32 can_id_flags = cf->can_id & CAN_ERR_MASK;
 	u8 *pc;
 
-	obuf[0] = 2;
-	obuf[1] = 1;
+	obuf[0] = PCAN_USB_MSG_TX_CAN;
+	obuf[1] = 1;	/* only one CAN frame is stored in the packet */
 
 	pc = obuf + PCAN_USB_MSG_HEADER_LEN;
 
@@ -839,12 +774,28 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
 		*pc |= PCAN_USB_STATUSLEN_EXT_ID;
 		pc++;
 
-		put_unaligned_le32((cf->can_id & CAN_ERR_MASK) << 3, pc);
+		can_id_flags <<= 3;
+
+		if (dev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
+			can_id_flags |= PCAN_USB_TX_SRR;
+
+		if (dev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
+			can_id_flags |= PCAN_USB_TX_AT;
+
+		put_unaligned_le32(can_id_flags, pc);
 		pc += 4;
 	} else {
 		pc++;
 
-		put_unaligned_le16((cf->can_id & CAN_ERR_MASK) << 5, pc);
+		can_id_flags <<= 5;
+
+		if (dev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
+			can_id_flags |= PCAN_USB_TX_SRR;
+
+		if (dev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
+			can_id_flags |= PCAN_USB_TX_AT;
+
+		put_unaligned_le16(can_id_flags, pc);
 		pc += 2;
 	}
 
@@ -854,6 +805,10 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
 		pc += cf->len;
 	}
 
+	/* SRR bit needs a writer id (useless here) */
+	if (can_id_flags & PCAN_USB_TX_SRR)
+		*pc++ = 0x80;
+
 	obuf[(*size)-1] = (u8)(stats->tx_packets & 0xff);
 
 	return 0;
@@ -928,6 +883,19 @@ static int pcan_usb_init(struct peak_usb_device *dev)
 		return err;
 	}
 
+	/* Since rev 4.1, PCAN-USB is able to make single-shot as well as
+	 * looped back frames.
+	 */
+	if (dev->device_rev >= 41) {
+		struct can_priv *priv = netdev_priv(dev->netdev);
+
+		priv->ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT |
+					    CAN_CTRLMODE_LOOPBACK;
+	} else {
+		dev_info(dev->netdev->dev.parent,
+			 "Firmware update available. Please contact support@peak-system.com\n");
+	}
+
 	dev_info(dev->netdev->dev.parent,
 		 "PEAK-System %s adapter hwrev %u serial %08X (%u channel)\n",
 		 pcan_usb.name, dev->device_rev, serial_number,