From: Konstantin Shkolnyy Date: Wed, 4 May 2016 21:56:52 +0000 (-0500) Subject: USB: serial: cp210x: fix hardware flow-control disable X-Git-Tag: v3.12.65~14 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=70104af05fc8ad4f85510b8d442d0bd1886ed716;p=thirdparty%2Fkernel%2Fstable.git USB: serial: cp210x: fix hardware flow-control disable commit a377f9e906af4df9071ba8ddba60188cb4013d93 upstream. A bug in the CRTSCTS handling caused RTS to alternate between CRTSCTS=0 => "RTS is transmit active signal" and CRTSCTS=1 => "RTS is used for receive flow control" instead of CRTSCTS=0 => "RTS is statically active" and CRTSCTS=1 => "RTS is used for receive flow control" This only happened after first having enabled CRTSCTS. Signed-off-by: Konstantin Shkolnyy Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control") [johan: reword commit message ] Signed-off-by: Johan Hovold [johan: backport to 4.4 ] Signed-off-by: Johan Hovold Signed-off-by: Jiri Slaby --- diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 4063099f429a2..17f737222b582 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -858,7 +858,7 @@ static void cp210x_set_termios(struct tty_struct *tty, } else { modem_ctl[0] &= ~0x7B; modem_ctl[0] |= 0x01; - modem_ctl[1] |= 0x40; + modem_ctl[1] = 0x40; dev_dbg(dev, "%s - flow control = NONE\n", __func__); }