diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index 04a3f1b756a8ad78f24c887959e6a51b1cb4d778..192b0d118df46d4136c5bd5bab872f35d51bcbc7 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -95,11 +95,16 @@ static void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val) spin_unlock_irqrestore(&priv->cmdreg_lock, flags); } +static int sja1000_is_absent(struct sja1000_priv *priv) +{ + return (priv->read_reg(priv, REG_MOD) == 0xFF); +} + static int sja1000_probe_chip(struct net_device *dev) { struct sja1000_priv *priv = netdev_priv(dev); - if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) { + if (priv->reg_base && sja1000_is_absent(priv)) { printk(KERN_INFO "%s: probing @0x%lX failed\n", DRV_NAME, dev->base_addr); return 0; @@ -493,6 +498,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { n++; status = priv->read_reg(priv, REG_SR); + /* check for absent controller due to hw unplug */ + if (status == 0xFF && sja1000_is_absent(priv)) + return IRQ_NONE; if (isrc & IRQ_WUI) dev_warn(dev->dev.parent, "wakeup interrupt\n"); @@ -509,6 +517,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) while (status & SR_RBS) { sja1000_rx(dev); status = priv->read_reg(priv, REG_SR); + /* check for absent controller */ + if (status == 0xFF && sja1000_is_absent(priv)) + return IRQ_NONE; } } if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {