From: Marc Kleine-Budde mkl@pengutronix.de
[ Upstream commit cd9f13c59461351d7a5fd07924264fb49b287359 ]
If the CAN controller goes into bus off, the do_set_mode() callback with CAN_MODE_START can be used to recover the controller, which then calls flexcan_chip_start(). If configured, this is done automatically by the framework or manually by the user.
In flexcan_chip_start() there is an explicit call to flexcan_transceiver_enable(), which does a regulator_enable() on the transceiver regulator. This results in a net usage counter increase, as there is no corresponding flexcan_transceiver_disable() in the bus off code path. This further leads to the transceiver stuck enabled, even if the CAN interface is shut down.
To fix this problem the flexcan_transceiver_enable()/flexcan_transceiver_disable() are moved out of flexcan_chip_start()/flexcan_chip_stop() into flexcan_open()/flexcan_close().
Fixes: e955cead0311 ("CAN: Add Flexcan CAN controller driver") Link: https://lore.kernel.org/r/20201118150148.2664024-1-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/can/flexcan.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 20a56f389c20c..4cbe8889f546f 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -1229,14 +1229,10 @@ static int flexcan_chip_start(struct net_device *dev) priv->write(reg_mecr, ®s->mecr); }
- err = flexcan_transceiver_enable(priv); - if (err) - goto out_chip_disable; - /* synchronize with the can bus */ err = flexcan_chip_unfreeze(priv); if (err) - goto out_transceiver_disable; + goto out_chip_disable;
priv->can.state = CAN_STATE_ERROR_ACTIVE;
@@ -1254,8 +1250,6 @@ static int flexcan_chip_start(struct net_device *dev)
return 0;
- out_transceiver_disable: - flexcan_transceiver_disable(priv); out_chip_disable: flexcan_chip_disable(priv); return err; @@ -1285,7 +1279,6 @@ static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error) priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL, ®s->ctrl);
- flexcan_transceiver_disable(priv); priv->can.state = CAN_STATE_STOPPED;
return 0; @@ -1321,10 +1314,14 @@ static int flexcan_open(struct net_device *dev) if (err) goto out_runtime_put;
- err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev); + err = flexcan_transceiver_enable(priv); if (err) goto out_close;
+ err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev); + if (err) + goto out_transceiver_disable; + priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN; priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) + (sizeof(priv->regs->mb[1]) / priv->mb_size); @@ -1373,6 +1370,8 @@ static int flexcan_open(struct net_device *dev) can_rx_offload_del(&priv->offload); out_free_irq: free_irq(dev->irq, dev); + out_transceiver_disable: + flexcan_transceiver_disable(priv); out_close: close_candev(dev); out_runtime_put: @@ -1391,6 +1390,7 @@ static int flexcan_close(struct net_device *dev)
can_rx_offload_del(&priv->offload); free_irq(dev->irq, dev); + flexcan_transceiver_disable(priv);
close_candev(dev); pm_runtime_put(priv->dev);