diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 9543b19d410c..6dcc3a3fe6d1 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -773,10 +774,37 @@ static int acm_tty_tiocmset(struct tty_struct *tty, return acm_set_control(acm, acm->ctrlout = newctrl); } +static int get_serial_info(struct acm *acm, struct serial_struct __user *info) +{ + struct serial_struct tmp; + + if (!info) + return -EINVAL; + + memset(&tmp, 0, sizeof(tmp)); + tmp.flags = ASYNC_LOW_LATENCY; + tmp.xmit_fifo_size = acm->writesize; + tmp.baud_base = le32_to_cpu(acm->line.dwDTERate); + + if (copy_to_user(info, &tmp, sizeof(tmp))) + return -EFAULT; + else + return 0; +} + static int acm_tty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { - return -ENOIOCTLCMD; + struct acm *acm = tty->driver_data; + int rv = -ENOIOCTLCMD; + + switch (cmd) { + case TIOCGSERIAL: /* gets serial port data */ + rv = get_serial_info(acm, (struct serial_struct __user *) arg); + break; + } + + return rv; } static const __u32 acm_tty_speed[] = {