On 2024/2/5 16:47, John Ogness wrote: > On 2024-02-04, Yicong Yang <yangyicong@xxxxxxxxxx> wrote: >> diff --git a/drivers/tty/serial/serial_port.c b/drivers/tty/serial/serial_port.c >> index 88975a4df306..60d1eec6b6b7 100644 >> --- a/drivers/tty/serial/serial_port.c >> +++ b/drivers/tty/serial/serial_port.c >> @@ -46,8 +46,28 @@ static int serial_port_runtime_resume(struct device *dev) >> return 0; >> } >> >> +static int serial_port_runtime_suspend(struct device *dev) >> +{ >> + struct serial_port_device *port_dev = to_serial_base_port_device(dev); >> + struct uart_port *port; >> + unsigned long flags; >> + >> + port = port_dev->port; >> + >> + if (port->flags & UPF_DEAD) >> + return 0; >> + >> + spin_lock_irqsave(&port->lock, flags); >> + if (__serial_port_busy(port)) >> + pm_request_resume(dev); >> + spin_unlock_irqrestore(&port->lock, flags); > > Please use the wrapper functions for the uart port lock: > > uart_port_lock_irqsave() > uart_port_unlock_irqrestore() > Sure. Thanks for the information.