[PATCH 5.12 023/677] USB: serial: xr: fix CSIZE handling

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 14:06:49 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit ea7ada4de2f7406150dd35ecd0302842587a464e upstream.

The XR21V141X does not have a 5- or 6-bit mode, but the current
implementation failed to properly restore the old setting when CS5 or
CS6 was requested. Instead an invalid request would be sent to the
device.

Fixes: c2d405aa86b4 ("USB: serial: add MaxLinear/Exar USB to Serial driver")
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 5.12
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/xr_serial.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/drivers/usb/serial/xr_serial.c
+++ b/drivers/usb/serial/xr_serial.c
@@ -468,6 +468,11 @@ static void xr_set_termios(struct tty_st
if (old_termios)
termios->c_cflag |= old_termios->c_cflag & CSIZE;
else
+ termios->c_cflag |= CS8;
+
+ if (C_CSIZE(tty) == CS7)
+ bits |= XR21V141X_UART_DATA_7;
+ else
bits |= XR21V141X_UART_DATA_8;
break;
case CS7: