[glsdk/meta-ti-glsdk.git] / recipes-kernel / linux / linux-ti33x-psp-3.2 / 3.2.9 / 0064-can-sja1000-fix-isr-hang-when-hw-is-unplugged-under-.patch
1 From 21c2e3679f5a2068edaf3ae26a8081897f7da66a Mon Sep 17 00:00:00 2001
2 From: Oliver Hartkopp <socketcan@hartkopp.net>
3 Date: Wed, 15 Feb 2012 17:51:56 +0100
4 Subject: [PATCH 64/72] can: sja1000: fix isr hang when hw is unplugged under
5 load
7 commit a7762b10c12a70c5dbf2253142764b728ac88c3a upstream.
9 In the case of hotplug enabled devices (PCMCIA/PCIeC) the removal of the
10 hardware can cause an infinite loop in the common sja1000 isr.
12 Use the already retrieved status register to indicate a possible hardware
13 removal and double check by reading the mode register in sja1000_is_absent.
15 Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
16 Acked-by: Wolfgang Grandegger <wg@grandegger.com>
17 Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
19 ---
20 drivers/net/can/sja1000/sja1000.c | 13 ++++++++++++-
21 1 file changed, 12 insertions(+), 1 deletion(-)
23 diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
24 index 04a3f1b..192b0d1 100644
25 --- a/drivers/net/can/sja1000/sja1000.c
26 +++ b/drivers/net/can/sja1000/sja1000.c
27 @@ -95,11 +95,16 @@ static void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val)
28 spin_unlock_irqrestore(&priv->cmdreg_lock, flags);
29 }
31 +static int sja1000_is_absent(struct sja1000_priv *priv)
32 +{
33 + return (priv->read_reg(priv, REG_MOD) == 0xFF);
34 +}
35 +
36 static int sja1000_probe_chip(struct net_device *dev)
37 {
38 struct sja1000_priv *priv = netdev_priv(dev);
40 - if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) {
41 + if (priv->reg_base && sja1000_is_absent(priv)) {
42 printk(KERN_INFO "%s: probing @0x%lX failed\n",
43 DRV_NAME, dev->base_addr);
44 return 0;
45 @@ -493,6 +498,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
46 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) {
47 n++;
48 status = priv->read_reg(priv, REG_SR);
49 + /* check for absent controller due to hw unplug */
50 + if (status == 0xFF && sja1000_is_absent(priv))
51 + return IRQ_NONE;
53 if (isrc & IRQ_WUI)
54 dev_warn(dev->dev.parent, "wakeup interrupt\n");
55 @@ -509,6 +517,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
56 while (status & SR_RBS) {
57 sja1000_rx(dev);
58 status = priv->read_reg(priv, REG_SR);
59 + /* check for absent controller */
60 + if (status == 0xFF && sja1000_is_absent(priv))
61 + return IRQ_NONE;
62 }
63 }
64 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
65 --
66 1.7.9.4