From: Oliver Neukum <oneukum@xxxxxxxx> commit 08dff274edda54310d6f1cf27b62fddf0f8d146e upstream. Counting break events is nice but we should actually report them to the tty layer. Fixes: 5a6a62bdb9257 ("cdc-acm: add TIOCMIWAIT") Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Link: https://lore.kernel.org/r/20210311133714.31881-1-oneukum@xxxxxxxx Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -313,8 +313,10 @@ static void acm_process_notification(str acm->iocount.dsr++; if (difference & ACM_CTRL_DCD) acm->iocount.dcd++; - if (newctrl & ACM_CTRL_BRK) + if (newctrl & ACM_CTRL_BRK) { acm->iocount.brk++; + tty_insert_flip_char(&acm->port, 0, TTY_BREAK); + } if (newctrl & ACM_CTRL_RI) acm->iocount.rng++; if (newctrl & ACM_CTRL_FRAMING)