From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wolfgang Grandegger , Oliver Hartkopp , Marc Kleine-Budde Subject: [PATCH 3.12 27/62] can: sja1000: fix {pre,post}_irq() handling and IRQ handler return value Date: Tue, 10 Dec 2013 00:00:58 -0800 Message-Id: <20131210080059.342079757@linuxfoundation.org> In-Reply-To: <20131210080057.415644748@linuxfoundation.org> References: <20131210080057.415644748@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Hartkopp 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 Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/sja1000/sja1000.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -494,20 +494,20 @@ irqreturn_t sja1000_interrupt(int irq, v uint8_t isrc, status; int n = 0; - /* Shared interrupts and IRQ off? */ - if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF) - return IRQ_NONE; - if (priv->pre_irq) priv->pre_irq(priv); + /* Shared interrupts and IRQ off? */ + if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF) + goto out; + while ((isrc = priv->read_reg(priv, SJA1000_IR)) && (n < SJA1000_MAX_IRQ)) { - n++; + status = priv->read_reg(priv, SJA1000_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"); @@ -535,7 +535,7 @@ irqreturn_t sja1000_interrupt(int irq, v status = priv->read_reg(priv, SJA1000_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)) { @@ -543,8 +543,9 @@ irqreturn_t sja1000_interrupt(int irq, v if (sja1000_err(dev, isrc, status)) break; } + n++; } - +out: if (priv->post_irq) priv->post_irq(priv);