[PATCH v3 1/2] can: flexcan: only change CAN state when link up in system PM
From: haibo . chen
Date: Fri Mar 14 2025 - 07:00:49 EST
From: Haibo Chen <haibo.chen@xxxxxxx>
After a suspend/resume cycle on a down interface, it will come up as
ERROR-ACTIVE.
$ ip -details -s -s a s dev flexcan0
3: flexcan0: <NOARP,ECHO> mtu 16 qdisc pfifo_fast state DOWN group default qlen 10
link/can promiscuity 0 allmulti 0 minmtu 0 maxmtu 0
can state STOPPED (berr-counter tx 0 rx 0) restart-ms 1000
$ sudo systemctl suspend
$ ip -details -s -s a s dev flexcan0
3: flexcan0: <NOARP,ECHO> mtu 16 qdisc pfifo_fast state DOWN group default qlen 10
link/can promiscuity 0 allmulti 0 minmtu 0 maxmtu 0
can state ERROR-ACTIVE (berr-counter tx 0 rx 0) restart-ms 1000
And only set CAN state to CAN_STATE_ERROR_ACTIVE when resume process
has no issue, otherwise keep in CAN_STATE_SLEEPING as suspend did.
Fixes: 4de349e786a3 ("can: flexcan: fix resume function")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
---
Changes for v3:
- only handle priv->can.state when netif_running(dev) return true in PM.
---
drivers/net/can/flexcan/flexcan-core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
index b347a1c93536..d4d342d8f490 100644
--- a/drivers/net/can/flexcan/flexcan-core.c
+++ b/drivers/net/can/flexcan/flexcan-core.c
@@ -2299,8 +2299,8 @@ static int __maybe_unused flexcan_suspend(struct device *device)
}
netif_stop_queue(dev);
netif_device_detach(dev);
+ priv->can.state = CAN_STATE_SLEEPING;
}
- priv->can.state = CAN_STATE_SLEEPING;
return 0;
}
@@ -2311,7 +2311,6 @@ static int __maybe_unused flexcan_resume(struct device *device)
struct flexcan_priv *priv = netdev_priv(dev);
int err;
- priv->can.state = CAN_STATE_ERROR_ACTIVE;
if (netif_running(dev)) {
netif_device_attach(dev);
netif_start_queue(dev);
@@ -2331,6 +2330,7 @@ static int __maybe_unused flexcan_resume(struct device *device)
flexcan_chip_interrupts_enable(dev);
}
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
}
return 0;
--
2.34.1