modem: modem_cmux: Clear DLCI pipes on open

This commit resets the receive ring buffer for each DLCI
pipe when they are opened. They may have old data stored
from last time they where opened.

Signed-off-by: Bjarki Arge Andreasen <[email protected]>

Author: Bjarki Arge Andreasen

subsys/modem/modem_cmux.c

@@ -401,6 +401,9 @@ static void modem_cmux_on_dlci_frame_ua(struct modem_cmux_dlci *dlci)
 		dlci->state = MODEM_CMUX_DLCI_STATE_OPEN;
 		modem_pipe_notify_opened(&dlci->pipe);
 		k_work_cancel_delayable(&dlci->open_work);
+		k_mutex_lock(&dlci->receive_rb_lock, K_FOREVER);
+		ring_buf_reset(&dlci->receive_rb);
+		k_mutex_unlock(&dlci->receive_rb_lock);
 		break;
 
 	case MODEM_CMUX_DLCI_STATE_CLOSING: