[PATCH] PM: domains: log failures to register always-on domains

From: Johan Hovold
Date: Thu Sep 29 2022 - 11:44:12 EST


Always-on PM domains must be on during initialisation or the domain is
currently silently rejected.

Print an error message in case an always-on domain is not on to make it
easier to debug drivers getting this wrong (e.g. by setting an always-on
genpd flag without making sure that the state matches).

Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
drivers/base/power/domain.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)


Both myself and Matthias have hit this with the Qualcomm GCC drivers
when updating static genpd flags directly instead of using/adding driver
specific flags to propagate the setting.

Johan


diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index bbfbf05b3446..7200e307effb 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2087,8 +2087,10 @@ int pm_genpd_init(struct generic_pm_domain *genpd,

/* Always-on domains must be powered on at initialization. */
if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
- !genpd_status_on(genpd))
+ !genpd_status_on(genpd)) {
+ pr_err("always-on PM domain %s is not on\n", genpd->name);
return -EINVAL;
+ }

/* Multiple states but no governor doesn't make sense. */
if (!gov && genpd->state_count > 1)
--
2.35.1