can: flexcan: fix shutdown: first disable chip, then all interrupts

When shutting down the CAN interface (ifconfig canX down) during high CAN bus
loads, the CAN core might hang and freeze the whole CPU.

This patch fixes the shutdown sequence by first disabling the CAN core then
disabling all interrupts.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 320bef2dba427f266511330bc11b1a4097368520..dcd69c9374aea08d48c42d4c2ca2ff4731363a8c 100644 (file)
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -827,14 +827,16 @@ static void flexcan_chip_stop(struct net_device *dev)
        struct flexcan_regs __iomem *regs = priv->base;
        u32 reg;
 
-       /* Disable all interrupts */
-       flexcan_write(0, &regs->imask1);
-
        /* Disable + halt module */
        reg = flexcan_read(&regs->mcr);
        reg |= FLEXCAN_MCR_MDIS | FLEXCAN_MCR_HALT;
        flexcan_write(reg, &regs->mcr);
 
+       /* Disable all interrupts */
+       flexcan_write(0, &regs->imask1);
+       flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
+                     &regs->ctrl);
+
        if (priv->reg_xceiver)
                regulator_disable(priv->reg_xceiver);
        priv->can.state = CAN_STATE_STOPPED;