1 files changed, 98 insertions, 59 deletions

diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
index 966316479485..a8fa0d6516b9 100644
--- a/drivers/net/can/sja1000/sja1000.c
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -52,6 +52,7 @@
 #include <linux/ptrace.h>
 #include <linux/string.h>
 #include <linux/errno.h>
+#include <linux/ethtool.h>
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
 #include <linux/if_ether.h>
@@ -60,7 +61,6 @@
 
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
-#include <linux/can/led.h>
 
 #include "sja1000.h"
 
@@ -184,8 +184,9 @@ static void chipset_init(struct net_device *dev)
 {
 	struct sja1000_priv *priv = netdev_priv(dev);
 
-	/* set clock divider and output control register */
-	priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN);
+	if (!(priv->flags & SJA1000_QUIRK_NO_CDR_REG))
+		/* set clock divider and output control register */
+		priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN);
 
 	/* set acceptance filter (accept all) */
 	priv->write_reg(priv, SJA1000_ACCC0, 0x00);
@@ -205,12 +206,13 @@ static void sja1000_start(struct net_device *dev)
 {
 	struct sja1000_priv *priv = netdev_priv(dev);
 
-	/* leave reset mode */
+	/* enter reset mode */
 	if (priv->can.state != CAN_STATE_STOPPED)
 		set_reset_mode(dev);
 
 	/* Initialize chip if uninitialized at this stage */
-	if (!(priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN))
+	if (!(priv->flags & SJA1000_QUIRK_NO_CDR_REG ||
+	      priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN))
 		chipset_init(dev);
 
 	/* Clear error counters and error code capture */
@@ -289,7 +291,7 @@ static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
 	u8 cmd_reg_val = 0x00;
 	int i;
 
-	if (can_dropped_invalid_skb(dev, skb))
+	if (can_dev_dropped_skb(dev, skb))
 		return NETDEV_TX_OK;
 
 	netif_stop_queue(dev);
@@ -383,8 +385,22 @@ static void sja1000_rx(struct net_device *dev)
 	sja1000_write_cmdreg(priv, CMD_RRB);
 
 	netif_rx(skb);
+}
+
+static irqreturn_t sja1000_reset_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+
+	netdev_dbg(dev, "performing a soft reset upon overrun\n");
 
-	can_led_event(dev, CAN_LED_EVENT_RX);
+	netif_tx_lock(dev);
+
+	can_free_echo_skb(dev, 0, NULL);
+	sja1000_set_mode(dev, CAN_MODE_START);
+
+	netif_tx_unlock(dev);
+
+	return IRQ_HANDLED;
 }
 
 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
@@ -397,25 +413,33 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 	enum can_state rx_state, tx_state;
 	unsigned int rxerr, txerr;
 	uint8_t ecc, alc;
+	int ret = 0;
 
 	skb = alloc_can_err_skb(dev, &cf);
-	if (skb == NULL)
-		return -ENOMEM;
 
 	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");
-		cf->can_id |= CAN_ERR_CRTL;
-		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+		if (skb) {
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+		}
+
 		stats->rx_over_errors++;
 		stats->rx_errors++;
 		sja1000_write_cmdreg(priv, CMD_CDO);	/* clear bit */
+
+		/* Some controllers needs additional handling upon overrun
+		 * condition: the controller may sometimes be totally confused
+		 * and refuse any new frame while its buffer is empty. The only
+		 * way to re-sync the read vs. write buffer offsets is to
+		 * stop any current handling and perform a reset.
+		 */
+		if (priv->flags & SJA1000_QUIRK_RESET_ON_OVERRUN)
+			ret = IRQ_WAKE_THREAD;
 	}
 
 	if (isrc & IRQ_EI) {
@@ -429,36 +453,46 @@ 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 && skb) {
+		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++;
-		stats->rx_errors++;
 
 		ecc = priv->read_reg(priv, SJA1000_ECC);
+		if (skb) {
+			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 
-		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
-
-		/* set error type */
-		switch (ecc & ECC_MASK) {
-		case ECC_BIT:
-			cf->data[2] |= CAN_ERR_PROT_BIT;
-			break;
-		case ECC_FORM:
-			cf->data[2] |= CAN_ERR_PROT_FORM;
-			break;
-		case ECC_STUFF:
-			cf->data[2] |= CAN_ERR_PROT_STUFF;
-			break;
-		default:
-			break;
-		}
+			/* set error type */
+			switch (ecc & ECC_MASK) {
+			case ECC_BIT:
+				cf->data[2] |= CAN_ERR_PROT_BIT;
+				break;
+			case ECC_FORM:
+				cf->data[2] |= CAN_ERR_PROT_FORM;
+				break;
+			case ECC_STUFF:
+				cf->data[2] |= CAN_ERR_PROT_STUFF;
+				break;
+			default:
+				break;
+			}
 
-		/* set error location */
-		cf->data[3] = ecc & ECC_SEG;
+			/* set error location */
+			cf->data[3] = ecc & ECC_SEG;
+		}
 
 		/* Error occurred during transmission? */
-		if ((ecc & ECC_DIR) == 0)
-			cf->data[2] |= CAN_ERR_PROT_TX;
+		if ((ecc & ECC_DIR) == 0) {
+			stats->tx_errors++;
+			if (skb)
+				cf->data[2] |= CAN_ERR_PROT_TX;
+		} else {
+			stats->rx_errors++;
+		}
 	}
 	if (isrc & IRQ_EPI) {
 		/* error passive interrupt */
@@ -474,8 +508,10 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 		netdev_dbg(dev, "arbitration lost interrupt\n");
 		alc = priv->read_reg(priv, SJA1000_ALC);
 		priv->can.can_stats.arbitration_lost++;
-		cf->can_id |= CAN_ERR_LOSTARB;
-		cf->data[0] = alc & 0x1f;
+		if (skb) {
+			cf->can_id |= CAN_ERR_LOSTARB;
+			cf->data[0] = alc & 0x1f;
+		}
 	}
 
 	if (state != priv->can.state) {
@@ -488,9 +524,12 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 			can_bus_off(dev);
 	}
 
+	if (!skb)
+		return -ENOMEM;
+
 	netif_rx(skb);
 
-	return 0;
+	return ret;
 }
 
 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
@@ -499,7 +538,8 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 	struct sja1000_priv *priv = netdev_priv(dev);
 	struct net_device_stats *stats = &dev->stats;
 	uint8_t isrc, status;
-	int n = 0;
+	irqreturn_t ret = 0;
+	int n = 0, err;
 
 	if (priv->pre_irq)
 		priv->pre_irq(priv);
@@ -508,8 +548,8 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 	if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF)
 		goto out;
 
-	while ((isrc = priv->read_reg(priv, SJA1000_IR)) &&
-	       (n < SJA1000_MAX_IRQ)) {
+	while ((n < SJA1000_MAX_IRQ) &&
+	       (isrc = priv->read_reg(priv, SJA1000_IR))) {
 
 		status = priv->read_reg(priv, SJA1000_SR);
 		/* check for absent controller due to hw unplug */
@@ -531,7 +571,6 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 				stats->tx_packets++;
 			}
 			netif_wake_queue(dev);
-			can_led_event(dev, CAN_LED_EVENT_TX);
 		}
 		if (isrc & IRQ_RI) {
 			/* receive interrupt */
@@ -545,19 +584,25 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 		}
 		if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
 			/* error interrupt */
-			if (sja1000_err(dev, isrc, status))
+			err = sja1000_err(dev, isrc, status);
+			if (err == IRQ_WAKE_THREAD)
+				ret = err;
+			if (err)
 				break;
 		}
 		n++;
 	}
 out:
+	if (!ret)
+		ret = (n) ? IRQ_HANDLED : IRQ_NONE;
+
 	if (priv->post_irq)
 		priv->post_irq(priv);
 
 	if (n >= SJA1000_MAX_IRQ)
 		netdev_dbg(dev, "%d messages handled in ISR", n);
 
-	return (n) ? IRQ_HANDLED : IRQ_NONE;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(sja1000_interrupt);
 
@@ -576,8 +621,9 @@ static int sja1000_open(struct net_device *dev)
 
 	/* register interrupt handler, if not done by the device driver */
 	if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
-		err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags,
-				  dev->name, (void *)dev);
+		err = request_threaded_irq(dev->irq, sja1000_interrupt,
+					   sja1000_reset_interrupt,
+					   priv->irq_flags, dev->name, (void *)dev);
 		if (err) {
 			close_candev(dev);
 			return -EAGAIN;
@@ -587,8 +633,6 @@ static int sja1000_open(struct net_device *dev)
 	/* init and start chi */
 	sja1000_start(dev);
 
-	can_led_event(dev, CAN_LED_EVENT_OPEN);
-
 	netif_start_queue(dev);
 
 	return 0;
@@ -606,8 +650,6 @@ static int sja1000_close(struct net_device *dev)
 
 	close_candev(dev);
 
-	can_led_event(dev, CAN_LED_EVENT_STOP);
-
 	return 0;
 }
 
@@ -655,28 +697,25 @@ static const struct net_device_ops sja1000_netdev_ops = {
 	.ndo_open	= sja1000_open,
 	.ndo_stop	= sja1000_close,
 	.ndo_start_xmit	= sja1000_start_xmit,
-	.ndo_change_mtu	= can_change_mtu,
+};
+
+static const struct ethtool_ops sja1000_ethtool_ops = {
+	.get_ts_info = ethtool_op_get_ts_info,
 };
 
 int register_sja1000dev(struct net_device *dev)
 {
-	int ret;
-
 	if (!sja1000_probe_chip(dev))
 		return -ENODEV;
 
 	dev->flags |= IFF_ECHO;	/* we support local echo */
 	dev->netdev_ops = &sja1000_netdev_ops;
+	dev->ethtool_ops = &sja1000_ethtool_ops;
 
 	set_reset_mode(dev);
 	chipset_init(dev);
 
-	ret =  register_candev(dev);
-
-	if (!ret)
-		devm_can_led_init(dev);
-
-	return ret;
+	return register_candev(dev);
 }
 EXPORT_SYMBOL_GPL(register_sja1000dev);