serdev: Drop dev_pm_domain_detach() call

[PATCH] serdev: Drop dev_pm_domain_detach() call

Posted by Claudiu 1 month, 1 week ago

From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

Starting with commit f99508074e78 ("PM: domains: Detach on
device_unbind_cleanup()"), there is no longer a need to call
dev_pm_domain_detach() in the bus remove function. The
device_unbind_cleanup() function now handles this to avoid
invoking devres cleanup handlers while the PM domain is
powered off, which could otherwise lead to failures as
described in the above-mentioned commit.

Drop the explicit dev_pm_domain_detach() call and rely instead
on the flags passed to dev_pm_domain_attach() to power off the
domain.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---
 drivers/tty/serdev/core.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index d16c207a1a9b..b33e708cb245 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -399,15 +399,12 @@ static int serdev_drv_probe(struct device *dev)
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	int ret;
 
-	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
+	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON |
+					PD_FLAG_DETACH_POWER_OFF);
 	if (ret)
 		return ret;
 
-	ret = sdrv->probe(to_serdev_device(dev));
-	if (ret)
-		dev_pm_domain_detach(dev, true);
-
-	return ret;
+	return sdrv->probe(to_serdev_device(dev));
 }
 
 static void serdev_drv_remove(struct device *dev)
@@ -415,8 +412,6 @@ static void serdev_drv_remove(struct device *dev)
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	if (sdrv->remove)
 		sdrv->remove(to_serdev_device(dev));
-
-	dev_pm_domain_detach(dev, true);
 }
 
 static const struct bus_type serdev_bus_type = {
-- 
2.43.0

Re: [PATCH] serdev: Drop dev_pm_domain_detach() call

Posted by Ulf Hansson 1 month, 1 week ago

On Wed, 27 Aug 2025 at 12:17, Claudiu <claudiu.beznea@tuxon.dev> wrote:
>
> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
>
> Starting with commit f99508074e78 ("PM: domains: Detach on
> device_unbind_cleanup()"), there is no longer a need to call
> dev_pm_domain_detach() in the bus remove function. The
> device_unbind_cleanup() function now handles this to avoid
> invoking devres cleanup handlers while the PM domain is
> powered off, which could otherwise lead to failures as
> described in the above-mentioned commit.
>
> Drop the explicit dev_pm_domain_detach() call and rely instead
> on the flags passed to dev_pm_domain_attach() to power off the
> domain.
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

Kind regards
Uffe


> ---
>  drivers/tty/serdev/core.c | 11 +++--------
>  1 file changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> index d16c207a1a9b..b33e708cb245 100644
> --- a/drivers/tty/serdev/core.c
> +++ b/drivers/tty/serdev/core.c
> @@ -399,15 +399,12 @@ static int serdev_drv_probe(struct device *dev)
>         const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
>         int ret;
>
> -       ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
> +       ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON |
> +                                       PD_FLAG_DETACH_POWER_OFF);
>         if (ret)
>                 return ret;
>
> -       ret = sdrv->probe(to_serdev_device(dev));
> -       if (ret)
> -               dev_pm_domain_detach(dev, true);
> -
> -       return ret;
> +       return sdrv->probe(to_serdev_device(dev));
>  }
>
>  static void serdev_drv_remove(struct device *dev)
> @@ -415,8 +412,6 @@ static void serdev_drv_remove(struct device *dev)
>         const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
>         if (sdrv->remove)
>                 sdrv->remove(to_serdev_device(dev));
> -
> -       dev_pm_domain_detach(dev, true);
>  }
>
>  static const struct bus_type serdev_bus_type = {
> --
> 2.43.0
>