Commit ad3faea0 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Greg Kroah-Hartman

serial: sh-sci: Fix late enablement of AUTORTS

commit 5f76895e upstream.

When changing hardware control flow for a UART with dedicated RTS/CTS
pins, the new AUTORTS state is not immediately reflected in the
hardware, but only when RTS is raised.  However, the serial core does
not call .set_mctrl() after .set_termios(), hence AUTORTS may only
become effective when the port is closed, and reopened later.
Note that this problem does not happen when manually using stty to
change CRTSCTS, as AUTORTS will work fine on next open.

To fix this, call .set_mctrl() from .set_termios() when dedicated
RTS/CTS pins are present, to refresh the AUTORTS or RTS state.
This is similar to what other drivers supporting AUTORTS do (e.g.
omap-serial).
Reported-by: default avatarBaumann, Christoph (C.) <cbaumann@visteon.com>
Fixes: 33f50ffc ("serial: sh-sci: Fix support for hardware-assisted RTS/CTS")
Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent a50aacf5
......@@ -2366,6 +2366,10 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
*/
udelay(DIV_ROUND_UP(10 * 1000000, baud));
}
if (port->flags & UPF_HARD_FLOW) {
/* Refresh (Auto) RTS */
sci_set_mctrl(port, port->mctrl);
}
#ifdef CONFIG_SERIAL_SH_SCI_DMA
/*
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment