From: Oliver Neukum <oneukum@xxxxxxx> An ioctl that does depends on communication with a device should prevent suspension of teh device. Signed-off-by: Oliver Neukum <oneukum@xxxxxxx> --- drivers/usb/class/cdc-acm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 92e28ec..8fe32eb 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -888,7 +888,13 @@ static int acm_tty_ioctl(struct tty_struct *tty, rv = set_serial_info(acm, (struct serial_struct __user *) arg); break; case TIOCMIWAIT: + rv = usb_autopm_get_interface(acm->control); + if (rv < 0) { + rv = -EIO; + break; + } rv = wait_serial_change(acm, arg); + usb_autopm_put_interface(acm->control); break; case TIOCGICOUNT: rv = get_serial_usage(acm, (struct serial_icounter_struct __user *) arg); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html