On 18.11.19 21:46, Tom Horsley wrote:
...
>
> I have no idea what an EMI is, but that's what starts everything.
I guess it is "electromagnetic interference"
/*
* EM interference sometimes causes badly shielded USB devices
* to be shutdown by the hub, this hack enables them again.
* Works at least with mouse driver.
*/
if (!(portstatus & USB_PORT_STAT_ENABLE)&& !connect_change && udev) {
dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
connect_change = 1;
}
USB3 devices can be sources of EMI.