The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 560706eff7c8e5621b0d63afe0866e0e1906e87e # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023101502-activism-unrefined-cfa3@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 560706eff7c8e5621b0d63afe0866e0e1906e87e Mon Sep 17 00:00:00 2001 From: Tony Lindgren <tony@xxxxxxxxxxx> Date: Tue, 26 Sep 2023 09:13:17 +0300 Subject: [PATCH] serial: 8250_omap: Fix errors with no_console_suspend We now get errors on system suspend if no_console_suspend is set as reported by Thomas. The errors started with commit 20a41a62618d ("serial: 8250_omap: Use force_suspend and resume for system suspend"). Let's fix the issue by checking for console_suspend_enabled in the system suspend and resume path. Note that with this fix the checks for console_suspend_enabled in omap8250_runtime_suspend() become useless. We now keep runtime PM usage count for an attached kernel console starting with commit bedb404e91bb ("serial: 8250_port: Don't use power management for kernel console"). Fixes: 20a41a62618d ("serial: 8250_omap: Use force_suspend and resume for system suspend") Cc: stable <stable@xxxxxxxxxx> Cc: Udit Kumar <u-kumar1@xxxxxx> Reported-by: Thomas Richard <thomas.richard@xxxxxxxxxxx> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Tested-by: Thomas Richard <thomas.richard@xxxxxxxxxxx> Reviewed-by: Dhruva Gole <d-gole@xxxxxx> Link: https://lore.kernel.org/r/20230926061319.15140-1-tony@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 26dd089d8e82..ca972fd37725 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1617,7 +1617,7 @@ 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; + int err = 0; serial8250_suspend_port(priv->line); @@ -1627,7 +1627,8 @@ static int omap8250_suspend(struct device *dev) if (!device_may_wakeup(dev)) priv->wer = 0; serial_out(up, UART_OMAP_WER, priv->wer); - err = pm_runtime_force_suspend(dev); + if (uart_console(&up->port) && console_suspend_enabled) + err = pm_runtime_force_suspend(dev); flush_work(&priv->qos_work); return err; @@ -1636,11 +1637,15 @@ static int omap8250_suspend(struct device *dev) static int omap8250_resume(struct device *dev) { struct omap8250_priv *priv = dev_get_drvdata(dev); + struct uart_8250_port *up = serial8250_get_port(priv->line); int err; - err = pm_runtime_force_resume(dev); - if (err) - return err; + if (uart_console(&up->port) && console_suspend_enabled) { + 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); @@ -1717,16 +1722,6 @@ static int omap8250_runtime_suspend(struct device *dev) if (priv->line >= 0) up = serial8250_get_port(priv->line); - /* - * When using 'no_console_suspend', the console UART must not be - * suspended. Since driver suspend is managed by runtime suspend, - * preventing runtime suspend (by returning error) will keep device - * active during suspend. - */ - if (priv->is_suspending && !console_suspend_enabled) { - if (up && uart_console(&up->port)) - return -EBUSY; - } if (priv->habit & UART_ERRATA_CLOCK_DISABLE) { int ret;
