USB: serial: cp210x: fix tiocmget error handling
The current tiocmget implementation would fail to report errors up the
stack and instead leaked a few bits from the stack as a mask of
modem-status flags.
Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index 54a4de0..f61477b 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -1077,7 +1077,9 @@
u8 control;
int result;
- cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
+ result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
+ if (result)
+ return result;
result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
|((control & CONTROL_RTS) ? TIOCM_RTS : 0)