From: Lukas Wunner <lukas@wunner.de>
Date: Sat, 21 Oct 2017 08:50:18 +0000 (+0200)
Subject: serial: omap: Fix EFR write on RTS deassertion
X-Git-Tag: v4.13.16~12
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5e4ef480d01bac3093ad2cd7a29804c4541dd08b;p=thirdparty%2Fkernel%2Fstable.git

serial: omap: Fix EFR write on RTS deassertion

commit 2a71de2f7366fb1aec632116d0549ec56d6a3940 upstream.

Commit 348f9bb31c56 ("serial: omap: Fix RTS handling") sought to enable
auto RTS upon manual RTS assertion and disable it on deassertion.
However it seems the latter was done incorrectly, it clears all bits in
the Extended Features Register *except* auto RTS.

Fixes: 348f9bb31c56 ("serial: omap: Fix RTS handling")
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 1ea05ac57aa71..670f7e334f933 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -693,7 +693,7 @@ static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
 		up->efr |= UART_EFR_RTS;
 	else
-		up->efr &= UART_EFR_RTS;
+		up->efr &= ~UART_EFR_RTS;
 	serial_out(up, UART_EFR, up->efr);
 	serial_out(up, UART_LCR, lcr);