On Wed, 5 Aug 2015, Greg KH wrote: > hm, wait, is this really the n_gsm line discipline? Or is it something > else? > > g_serial is the device side of a serial connection, there is no "cable > removed" notification that it even knows about, that has to come from > the gadget driver somehow, which you should listen for and then kick > your userspace program.
There is the gserial_disconnect() callback, which gets invoked when the Vbus power (provided by the host) is removed. It's a pretty good indicator that the USB cable has been unplugged. I don't understand all the stuff that gserial_disconnect() does, but it ought to be more or less equivalent to a "hangup" -- as the kerneldoc says. If it doesn't do what users expect, there's probably a bug somewhere. Of course, it's possible that the callback does not get invoked in Laszlo's case. Then the question would be: Why not? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
