From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH 2/4] serial: 8250: Copy mctrl when register port. Date: Wed, 06 Jun 2018 15:01:05 +0300 Message-ID: References: <20180606094942.71190-1-giulio.benetti@micronovasrl.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180606094942.71190-1-giulio.benetti@micronovasrl.com> Sender: linux-kernel-owner@vger.kernel.org To: Giulio Benetti Cc: matwey.kornilov@gmail.com, Greg Kroah-Hartman , Jiri Slaby , Matthias Brugger , Kees Cook , Allen Pais , Sean Young , "open list:SERIAL DRIVERS" , open list List-Id: linux-serial@vger.kernel.org On Wed, 2018-06-06 at 11:49 +0200, Giulio Benetti wrote: > RS485 can modify mctrl on startup, especially when RTS_AFTER_SEND is > on > TIOCM_RTS is set, then need to keep it set when registering port. > > Copy mctrl to new port too. > Not sure if it would be useful. Seems the only em485 user, i.e. OMAP, does survive without that. Moreover, often individual drivers override ->set_mctrl() callback. So, real example is needed to explain why. > Signed-off-by: Giulio Benetti > --- > drivers/tty/serial/8250/8250_core.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/tty/serial/8250/8250_core.c > b/drivers/tty/serial/8250/8250_core.c > index c8c2b260c681..c8e62fbd6570 100644 > --- a/drivers/tty/serial/8250/8250_core.c > +++ b/drivers/tty/serial/8250/8250_core.c > @@ -993,6 +993,7 @@ int serial8250_register_8250_port(struct > uart_8250_port *up) > uart->port.unthrottle = up->port.unthrottle; > uart->port.rs485_config = up- > >port.rs485_config; > uart->port.rs485 = up->port.rs485; > + uart->port.mctrl = up->port.mctrl; > uart->dma = up->dma; > uart->em485 = up->em485; > -- Andy Shevchenko Intel Finland Oy