From: Konstantin Shkolnyy <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== 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 <[email protected]> Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control") [johan: reword commit message ] Signed-off-by: Johan Hovold <[email protected]> [johan: backport to 4.4 ] Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- drivers/usb/serial/cp210x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 4063099f429a..17f737222b58 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__); } -- 2.10.1
