Re: [PATCH RFC 4/5] usb: cdc-acm: Enable serdev support

[Oliver Neukum]

On Fr, 2019-01-04 at 12:21 +0100, Andreas FÃrber  wrote:
> Switch from tty_port_register_device() to tty_port_register_device_serdev()
> and from tty_unregister_device() to tty_port_unregister_device().
> 
> On removal of a serdev driver sometimes count mismatch warnings were seen:
> 
>   ttyACM ttyACM0: tty_hangup: tty->count(1) != (#fd's(0) + #kopen's(0))
>   ttyACM ttyACM0: tty_port_close_start: tty->count = 1 port count = 0
> 
> Note: The serdev drivers appear to probe asynchronously as soon as they
> are registered. Should the USB quirks in probe be moved before registration?
> No noticeable difference for the devices at hand.

That is quite drastic a change.
Johan, how complete in terms of features is serdev?

Are you refering to CLEAR_HALT_CONDITIONS in terms of quirks?

	Regards
		Oliver