PM / Domains: Take .power_off() error code into account

Currently pm_genpd_poweroff() discards error codes returned by
the PM domain's .power_off() callback, because it's safer to always
regard the domain as inaccessible to drivers after a failing
.power_off().  Still, there are situations in which the low-level
code may want to indicate that it doesn't want to power off the
domain, so allow it to do that by returning -EBUSY from .power_off().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

1 files changed, 10 insertions, 2 deletions

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 00ed4f32a4de..be8714aa9dd6 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -312,8 +312,16 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
                 }
         }
 
-        if (genpd->power_off)
-                genpd->power_off(genpd);
+        if (genpd->power_off) {
+                ret = genpd->power_off(genpd);
+                if (ret == -EBUSY) {
+                        genpd_set_active(genpd);
+                        if (parent)
+                                genpd_release_lock(parent);
+
+                        goto out;
+                }
+        }
 
         genpd->status = GPD_STATE_POWER_OFF;