drm: display: Drop dev_pm_domain_detach() call

[PATCH] drm: display: 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/gpu/drm/display/drm_dp_aux_bus.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c
index 2d279e82922f..191664900ac7 100644
--- a/drivers/gpu/drm/display/drm_dp_aux_bus.c
+++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c
@@ -58,13 +58,14 @@ static int dp_aux_ep_probe(struct device *dev)
 		container_of(aux_ep, struct dp_aux_ep_device_with_data, aux_ep);
 	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 dev_err_probe(dev, ret, "Failed to attach to PM Domain\n");
 
 	ret = aux_ep_drv->probe(aux_ep);
 	if (ret)
-		goto err_attached;
+		return ret;
 
 	if (aux_ep_with_data->done_probing) {
 		ret = aux_ep_with_data->done_probing(aux_ep->aux);
@@ -88,8 +89,6 @@ static int dp_aux_ep_probe(struct device *dev)
 err_probed:
 	if (aux_ep_drv->remove)
 		aux_ep_drv->remove(aux_ep);
-err_attached:
-	dev_pm_domain_detach(dev, true);
 
 	return ret;
 }
@@ -107,7 +106,6 @@ static void dp_aux_ep_remove(struct device *dev)
 
 	if (aux_ep_drv->remove)
 		aux_ep_drv->remove(aux_ep);
-	dev_pm_domain_detach(dev, true);
 }
 
 /**
-- 
2.43.0

Re: [PATCH] drm: display: Drop dev_pm_domain_detach() call

Posted by Ulf Hansson 1 month, 1 week ago

On Wed, 27 Aug 2025 at 12:08, 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/gpu/drm/display/drm_dp_aux_bus.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> index 2d279e82922f..191664900ac7 100644
> --- a/drivers/gpu/drm/display/drm_dp_aux_bus.c
> +++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> @@ -58,13 +58,14 @@ static int dp_aux_ep_probe(struct device *dev)
>                 container_of(aux_ep, struct dp_aux_ep_device_with_data, aux_ep);
>         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 dev_err_probe(dev, ret, "Failed to attach to PM Domain\n");
>
>         ret = aux_ep_drv->probe(aux_ep);
>         if (ret)
> -               goto err_attached;
> +               return ret;
>
>         if (aux_ep_with_data->done_probing) {
>                 ret = aux_ep_with_data->done_probing(aux_ep->aux);
> @@ -88,8 +89,6 @@ static int dp_aux_ep_probe(struct device *dev)
>  err_probed:
>         if (aux_ep_drv->remove)
>                 aux_ep_drv->remove(aux_ep);
> -err_attached:
> -       dev_pm_domain_detach(dev, true);
>
>         return ret;
>  }
> @@ -107,7 +106,6 @@ static void dp_aux_ep_remove(struct device *dev)
>
>         if (aux_ep_drv->remove)
>                 aux_ep_drv->remove(aux_ep);
> -       dev_pm_domain_detach(dev, true);
>  }
>
>  /**
> --
> 2.43.0
>