diff options
author | Oliver Hartkopp <socketcan@hartkopp.net> | 2012-02-15 11:51:56 -0500 |
---|---|---|
committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2012-02-20 05:36:56 -0500 |
commit | a7762b10c12a70c5dbf2253142764b728ac88c3a (patch) | |
tree | dd2dba7c245118fee835fb72935ff885e7fddda8 /drivers/net/can | |
parent | 64f0a836f600e9c31ffd511713ab5d328aa96ac8 (diff) |
can: sja1000: fix isr hang when hw is unplugged under load
In the case of hotplug enabled devices (PCMCIA/PCIeC) the removal of the
hardware can cause an infinite loop in the common sja1000 isr.
Use the already retrieved status register to indicate a possible hardware
removal and double check by reading the mode register in sja1000_is_absent.
Cc: stable@kernel.org [3.2+]
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'drivers/net/can')
-rw-r--r-- | drivers/net/can/sja1000/sja1000.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index 04a3f1b756a8..192b0d118df4 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) | |||
95 | spin_unlock_irqrestore(&priv->cmdreg_lock, flags); | 95 | spin_unlock_irqrestore(&priv->cmdreg_lock, flags); |
96 | } | 96 | } |
97 | 97 | ||
98 | static int sja1000_is_absent(struct sja1000_priv *priv) | ||
99 | { | ||
100 | return (priv->read_reg(priv, REG_MOD) == 0xFF); | ||
101 | } | ||
102 | |||
98 | static int sja1000_probe_chip(struct net_device *dev) | 103 | static int sja1000_probe_chip(struct net_device *dev) |
99 | { | 104 | { |
100 | struct sja1000_priv *priv = netdev_priv(dev); | 105 | struct sja1000_priv *priv = netdev_priv(dev); |
101 | 106 | ||
102 | if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) { | 107 | if (priv->reg_base && sja1000_is_absent(priv)) { |
103 | printk(KERN_INFO "%s: probing @0x%lX failed\n", | 108 | printk(KERN_INFO "%s: probing @0x%lX failed\n", |
104 | DRV_NAME, dev->base_addr); | 109 | DRV_NAME, dev->base_addr); |
105 | return 0; | 110 | return 0; |
@@ -493,6 +498,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) | |||
493 | while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { | 498 | while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { |
494 | n++; | 499 | n++; |
495 | status = priv->read_reg(priv, REG_SR); | 500 | status = priv->read_reg(priv, REG_SR); |
501 | /* check for absent controller due to hw unplug */ | ||
502 | if (status == 0xFF && sja1000_is_absent(priv)) | ||
503 | return IRQ_NONE; | ||
496 | 504 | ||
497 | if (isrc & IRQ_WUI) | 505 | if (isrc & IRQ_WUI) |
498 | dev_warn(dev->dev.parent, "wakeup interrupt\n"); | 506 | dev_warn(dev->dev.parent, "wakeup interrupt\n"); |
@@ -509,6 +517,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) | |||
509 | while (status & SR_RBS) { | 517 | while (status & SR_RBS) { |
510 | sja1000_rx(dev); | 518 | sja1000_rx(dev); |
511 | status = priv->read_reg(priv, REG_SR); | 519 | status = priv->read_reg(priv, REG_SR); |
520 | /* check for absent controller */ | ||
521 | if (status == 0xFF && sja1000_is_absent(priv)) | ||
522 | return IRQ_NONE; | ||
512 | } | 523 | } |
513 | } | 524 | } |
514 | if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { | 525 | if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { |