Re: [PATCH 2/2] pch_uart: Delete modem status interrupt enable code

Alan Cox
2011-11-02T11:01:13Z

> Called ".get_mctrl" function, other software can know incoming carrier
> detection.
> Or you mean a uart driver must detect incoming carrier with interrupt ?

If a user opens a tty port which has no carrier signal then the open is
supposed to block until the carrier is raised unless either clocal
termios or O_NDELAY open flags are set.

That usually means you need to take the carrier raise interrupt in order
to wake out of open in this case.

Alan