From c9d2325cdb92fd4a6362ea792d93571195741675 Mon Sep 17 00:00:00 2001 From: Vijaya Krishna Nivarthi Date: Mon, 16 May 2022 14:50:10 +0530 Subject: [PATCH] serial: core: Do stop_rx in suspend path for console if console_suspend is disabled For the case of console_suspend disabled, if back to back suspend/resume test is executed, at the end of test, sometimes console would appear to be frozen not responding to input. This would happen because, during resume, rx transactions can come in before system is ready, malfunction of rx happens in turn resulting in console appearing to be stuck. Do a stop_rx in suspend sequence to prevent this. Signed-off-by: Vijaya Krishna Nivarthi Link: https://lore.kernel.org/r/1652692810-31148-1-git-send-email-quic_vnivarth@quicinc.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/serial_core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 82a1770..9a85b41 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2211,9 +2211,16 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport) } put_device(tty_dev); - /* Nothing to do if the console is not suspending */ - if (!console_suspend_enabled && uart_console(uport)) + /* + * Nothing to do if the console is not suspending + * except stop_rx to prevent any asynchronous data + * over RX line. Re-start_rx, when required, is + * done by set_termios in resume sequence + */ + if (!console_suspend_enabled && uart_console(uport)) { + uport->ops->stop_rx(uport); goto unlock; + } uport->suspended = 1; -- 2.7.4