[PATCH 2/2] USB: cdc-acm: fix break reporting

From: Johan Hovold
Date: Wed Sep 29 2021 - 05:10:09 EST

A recent change that started reporting break events forgot to push the
event to the line discipline, which meant that a detected break would
not be reported until further characters had been receive (the port
could even have been closed and reopened in between).

Fixes: 08dff274edda ("cdc-acm: fix BREAK rx code path adding necessary calls")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
drivers/usb/class/cdc-acm.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index c7a1736720e7..7b2e2420ecae 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -340,6 +340,9 @@ static void acm_process_notification(struct acm *acm, unsigned char *buf)
spin_unlock_irqrestore(&acm->read_lock, flags);

+ if (newctrl & ACM_CTRL_BRK)
+ tty_flip_buffer_push(&acm->port);
if (difference)