From: Tony Lindgren <tony@xxxxxxxxxxx> [ 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> --- drivers/tty/serial/8250/8250_omap.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index af39a2c4c2eee..e26ac3f42e05c 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 -- 2.39.2