This is a note to let you know that I've just added the patch titled serial: 8250_omap: Use force_suspend and resume for system suspend to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-8250_omap-use-force_suspend-and-resume-for-sy.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f5bd394c4b70f5c915d01a8ab74c27e934303ecb Author: Tony Lindgren <tony@xxxxxxxxxxx> Date: Wed Jun 14 07:59:19 2023 +0300 serial: 8250_omap: Use force_suspend and resume for system suspend [ Upstream commit 20a41a62618df85f3a2981008edec5cadd785e0a ] We should not rely on autosuspend timeout for system suspend. Instead, let's use force_suspend and force_resume functions. Otherwise the serial port controller device may not be idled on suspend. As we are doing a register write on suspend to configure the serial port, we still need to runtime PM resume the port on suspend. While at it, let's switch to pm_runtime_resume_and_get() and check for errors returned. And let's add the missing line break before return to the suspend function while at it. Fixes: 09d8b2bdbc5c ("serial: 8250: omap: Provide ability to enable/disable UART as wakeup source") Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Tested-by: Dhruva Gole <d-gole@xxxxxx> Message-ID: <20230614045922.4798-1-tony@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index de0447c87846b..a6b374c026a87 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1521,25 +1521,35 @@ static int omap8250_suspend(struct device *dev) { struct omap8250_priv *priv = dev_get_drvdata(dev); struct uart_8250_port *up = serial8250_get_port(priv->line); + int err; serial8250_suspend_port(priv->line); - pm_runtime_get_sync(dev); + err = pm_runtime_resume_and_get(dev); + if (err) + return err; if (!device_may_wakeup(dev)) priv->wer = 0; serial_out(up, UART_OMAP_WER, priv->wer); - pm_runtime_mark_last_busy(dev); - pm_runtime_put_autosuspend(dev); - + err = pm_runtime_force_suspend(dev); flush_work(&priv->qos_work); - return 0; + + return err; } static int omap8250_resume(struct device *dev) { struct omap8250_priv *priv = dev_get_drvdata(dev); + int err; + err = pm_runtime_force_resume(dev); + if (err) + return err; serial8250_resume_port(priv->line); + /* Paired with pm_runtime_resume_and_get() in omap8250_suspend() */ + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + return 0; } #else