When turning the network interface down, es58x_stop() is called and will send a command to the ES58x device to disable the channel c.f. es58x_ops::disable_channel(). However, if the device gets unplugged while the network interface is still up, es58x_ops::disable_channel() will obviously fail to send the URB command and the driver emits below error message: es58x_submit_urb: USB send urb failure: -ENODEV Check the usb device state before sending the disable channel command in order to silence above error message. Update the documentation of es58x_stop() accordingly. The check being added in es58x_stop() is: if (es58x_dev->udev->state >= USB_STATE_UNAUTHENTICATED) This is just the negation of the check done in usb_submit_urb()[1]. [1] usb_submit_urb(), verify usb device's state. Link: https://elixir.bootlin.com/linux/v6.1/source/drivers/usb/core/urb.c#L384 Fixes: 8537257874e9 ("can: etas_es58x: add core support for ETAS ES58X CAN USB interfaces") Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx> --- As far as I know, there doesn't seem to be an helper function to check udev->state values. If anyone is aware of such helper function, let me know.. --- drivers/net/can/usb/etas_es58x/es58x_core.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/usb/etas_es58x/es58x_core.c b/drivers/net/can/usb/etas_es58x/es58x_core.c index 3e87f4c1547c..916bd9e2e9ea 100644 --- a/drivers/net/can/usb/etas_es58x/es58x_core.c +++ b/drivers/net/can/usb/etas_es58x/es58x_core.c @@ -1817,9 +1817,10 @@ static int es58x_open(struct net_device *netdev) * es58x_stop() - Disable the network device. * @netdev: CAN network device. * - * Called when the network transitions to the down state. If all the - * channels of the device are closed, free the URB resources which are - * not needed anymore. + * Called when the network interface transitions to the down + * state. Send a disable command to the device if it is still + * connected. If all the channels of the device are closed, free the + * URB resources which are not needed anymore. * * Return: zero on success, errno when any error occurs. */ @@ -1830,9 +1831,12 @@ static int es58x_stop(struct net_device *netdev) int ret; netif_stop_queue(netdev); - ret = es58x_dev->ops->disable_channel(priv); - if (ret) - return ret; + + if (es58x_dev->udev->state >= USB_STATE_UNAUTHENTICATED) { + ret = es58x_dev->ops->disable_channel(priv); + if (ret) + return ret; + } priv->can.state = CAN_STATE_STOPPED; es58x_can_reset_echo_fifo(netdev); -- 2.39.1
