diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 792fbab3dfc4..c71a7ef08b05 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -123,6 +123,7 @@ static const struct genpd_lock_ops genpd_spin_ops = { #define genpd_status_on(genpd) (genpd->status == GPD_STATE_ACTIVE) #define genpd_is_irq_safe(genpd) (genpd->flags & GENPD_FLAG_IRQ_SAFE) +#define genpd_is_always_on(genpd) (genpd->flags & GENPD_FLAG_ALWAYS_ON) static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev, struct generic_pm_domain *genpd) @@ -300,7 +301,12 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, if (!genpd_status_on(genpd) || genpd->prepared_count > 0) return 0; - if (atomic_read(&genpd->sd_count) > 0) + /* + * Abort power off for the PM domain in the following situations: + * (1) The domain is configured as always on. + * (2) When the domain has a subdomain being powered on. + */ + if (genpd_is_always_on(genpd) || atomic_read(&genpd->sd_count) > 0) return -EBUSY; list_for_each_entry(pdd, &genpd->dev_list, list_node) { @@ -752,7 +758,7 @@ static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock, { struct gpd_link *link; - if (!genpd_status_on(genpd)) + if (!genpd_status_on(genpd) || genpd_is_always_on(genpd)) return; if (genpd->suspended_count != genpd->device_count @@ -1491,6 +1497,10 @@ int pm_genpd_init(struct generic_pm_domain *genpd, genpd->dev_ops.start = pm_clk_resume; } + /* Always-on domains must be powered on at initialization. */ + if (genpd_is_always_on(genpd) && !genpd_status_on(genpd)) + return -EINVAL; + /* Use only one "off" state if there were no states declared */ if (genpd->state_count == 0) { ret = genpd_set_default_power_state(genpd); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 5339ed5bd6f9..9b6abe632587 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -20,6 +20,7 @@ /* Defines used for the flags field in the struct generic_pm_domain */ #define GENPD_FLAG_PM_CLK (1U << 0) /* PM domain uses PM clk */ #define GENPD_FLAG_IRQ_SAFE (1U << 1) /* PM domain operates in atomic */ +#define GENPD_FLAG_ALWAYS_ON (1U << 2) /* PM domain is always powered on */ enum gpd_status { GPD_STATE_ACTIVE = 0, /* PM domain is active */