diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index 4719806e3a9f..0ada0e160e93 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -387,6 +387,16 @@ static void sja1000_rx(struct net_device *dev) 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"); + sja1000_start(dev); + + return IRQ_HANDLED; +} + static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) { struct sja1000_priv *priv = netdev_priv(dev); @@ -397,6 +407,7 @@ 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) @@ -413,6 +424,15 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) 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) { @@ -492,7 +512,7 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) netif_rx(skb); - return 0; + return ret; } irqreturn_t sja1000_interrupt(int irq, void *dev_id) @@ -548,6 +568,8 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { /* error interrupt */ err = sja1000_err(dev, isrc, status); + if (err == IRQ_WAKE_THREAD) + ret = err; if (err) break; } @@ -582,8 +604,9 @@ 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; diff --git a/drivers/net/can/sja1000/sja1000.h b/drivers/net/can/sja1000/sja1000.h index 7f736f1df547..f015e39e2224 100644 --- a/drivers/net/can/sja1000/sja1000.h +++ b/drivers/net/can/sja1000/sja1000.h @@ -147,6 +147,7 @@ */ #define SJA1000_CUSTOM_IRQ_HANDLER BIT(0) #define SJA1000_QUIRK_NO_CDR_REG BIT(1) +#define SJA1000_QUIRK_RESET_ON_OVERRUN BIT(2) /* * SJA1000 private data structure diff --git a/drivers/net/can/sja1000/sja1000_platform.c b/drivers/net/can/sja1000/sja1000_platform.c index b4889b5746e5..4e59952c66d4 100644 --- a/drivers/net/can/sja1000/sja1000_platform.c +++ b/drivers/net/can/sja1000/sja1000_platform.c @@ -106,7 +106,7 @@ static void sp_technologic_init(struct sja1000_priv *priv, struct device_node *o static void sp_rzn1_init(struct sja1000_priv *priv, struct device_node *of) { - priv->flags = SJA1000_QUIRK_NO_CDR_REG; + priv->flags = SJA1000_QUIRK_NO_CDR_REG | SJA1000_QUIRK_RESET_ON_OVERRUN; } static void sp_populate(struct sja1000_priv *priv, @@ -277,6 +277,9 @@ static int sp_probe(struct platform_device *pdev) priv->irq_flags = IRQF_SHARED; } + if (priv->flags & SJA1000_QUIRK_RESET_ON_OVERRUN) + priv->irq_flags |= IRQF_ONESHOT; + dev->irq = irq; priv->reg_base = addr;