From f7c02bf438f74ce4c7a8fb0c79cd435d85a795be Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Thu, 21 Nov 2013 18:03:07 +0100 Subject: [PATCH] can: sja1000: fix {pre,post}_irq() handling and IRQ handler return value commit 2fea6cd303c0d0cd9067da31d873b6a6d5bd75e7 upstream. This patch fixes the issue that the sja1000_interrupt() function may have returned IRQ_NONE without processing the optional pre_irq() and post_irq() function before. Further the irq processing counter 'n' is moved to the end of the while statement to return correct IRQ_[NONE|HANDLED] values at error conditions. Reported-by: Wolfgang Grandegger Acked-by: Wolfgang Grandegger Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde [bwh: Backported to 3.2: s/SJA1000_IER/REG_IER/; s/SJA1000_IR/REG_IR/] Signed-off-by: Ben Hutchings Cc: Qiang Huang Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/sja1000/sja1000.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index c2309ec..2d3ad72 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -487,19 +487,19 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) uint8_t isrc, status; int n = 0; - /* Shared interrupts and IRQ off? */ - if (priv->read_reg(priv, REG_IER) == IRQ_OFF) - return IRQ_NONE; - if (priv->pre_irq) priv->pre_irq(priv); + /* Shared interrupts and IRQ off? */ + if (priv->read_reg(priv, REG_IER) == IRQ_OFF) + goto out; + while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { - n++; + status = priv->read_reg(priv, SJA1000_REG_SR); /* check for absent controller due to hw unplug */ if (status == 0xFF && sja1000_is_absent(priv)) - return IRQ_NONE; + goto out; if (isrc & IRQ_WUI) netdev_warn(dev, "wakeup interrupt\n"); @@ -518,7 +518,7 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) status = priv->read_reg(priv, SJA1000_REG_SR); /* check for absent controller */ if (status == 0xFF && sja1000_is_absent(priv)) - return IRQ_NONE; + goto out; } } if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { @@ -526,8 +526,9 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) if (sja1000_err(dev, isrc, status)) break; } + n++; } - +out: if (priv->post_irq) priv->post_irq(priv); -- 2.7.4