[PATCH 3.16 220/306] USB: cdc-acm: fix TIOCMIWAIT

From: Ben Hutchings
Date: Wed Feb 15 2017 - 19:11:04 EST

3.16.40-rc1 review patch. If anyone has any objections, please let me know.


From: Johan Hovold <johan@xxxxxxxxxx>

commit 18266403f3fe507f0246faa1d5432333a2f139ca upstream.

The TIOCMIWAIT implementation would return -EINVAL if any of the three
supported signals were included in the mask.

Instead of returning an error in case TIOCM_CTS is included, simply
drop the mask check completely, which is in accordance with how other
drivers implement this ioctl.

Fixes: 5a6a62bdb925 ("cdc-acm: add TIOCMIWAIT")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Acked-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
drivers/usb/class/cdc-acm.c | 2 --
1 file changed, 2 deletions(-)

--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -867,8 +867,6 @@ static int wait_serial_change(struct acm
DECLARE_WAITQUEUE(wait, current);
struct async_icount old, new;

- if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD ))
- return -EINVAL;
do {
old = acm->oldcount;