[PATCH v6 1/3] pmdomain: core: introduce dev_pm_genpd_is_on()
From: Hiago De Franco <hidden>
Date: 2025-06-26 21:59:37
Also in:
imx, linux-pm, linux-remoteproc, lkml
Subsystem:
generic pm domains, power management core, the rest · Maintainers:
Ulf Hansson, "Rafael J. Wysocki", Linus Torvalds
From: Hiago De Franco <redacted> This helper function returns the current power status of a given generic power domain. As example, remoteproc/imx_rproc.c can now use this function to check the power status of the remote core to properly set "attached" or "offline" modes. Suggested-by: Ulf Hansson <redacted> Reviewed-by: Bjorn Andersson <andersson@kernel.org> Signed-off-by: Hiago De Franco <redacted> --- v5 -> v6: - Added Bjorn reviewed-by. v4 -> v5: - s/dev_pm_genpd_is_on/dev_pm_genpd_is_on()/ in function description. - Updated function description to be explicit the function reflects the current power status and that this might change after the function returns, especially if the genpd is shared. v3 -> v4: - New patch. --- drivers/pmdomain/core.c | 33 +++++++++++++++++++++++++++++++++ include/linux/pm_domain.h | 6 ++++++ 2 files changed, 39 insertions(+)
diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
index ff5c7f2b69ce..2f387e15cb75 100644
--- a/drivers/pmdomain/core.c
+++ b/drivers/pmdomain/core.c@@ -758,6 +758,39 @@ int dev_pm_genpd_rpm_always_on(struct device *dev, bool on) } EXPORT_SYMBOL_GPL(dev_pm_genpd_rpm_always_on); +/** + * dev_pm_genpd_is_on() - Get device's current power domain status + * + * @dev: Device to get the current power status + * + * This function checks whether the generic power domain associated with the + * given device is on or not by verifying if genpd_status_on equals + * GENPD_STATE_ON. + * + * Note: this function returns the power status of the genpd at the time of the + * call. The power status may change after due to activity from other devices + * sharing the same genpd. Therefore, this information should not be relied for + * long-term decisions about the device power state. + * + * Return: 'true' if the device's power domain is on, 'false' otherwise. + */ +bool dev_pm_genpd_is_on(struct device *dev) +{ + struct generic_pm_domain *genpd; + bool is_on; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return false; + + genpd_lock(genpd); + is_on = genpd_status_on(genpd); + genpd_unlock(genpd); + + return is_on; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_is_on); + /** * pm_genpd_inc_rejected() - Adjust the rejected/usage counts for an idle-state. *
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 0b18160901a2..c12580b6579b 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h@@ -301,6 +301,7 @@ void dev_pm_genpd_synced_poweroff(struct device *dev); int dev_pm_genpd_set_hwmode(struct device *dev, bool enable); bool dev_pm_genpd_get_hwmode(struct device *dev); int dev_pm_genpd_rpm_always_on(struct device *dev, bool on); +bool dev_pm_genpd_is_on(struct device *dev); extern struct dev_power_governor simple_qos_governor; extern struct dev_power_governor pm_domain_always_on_gov;
@@ -393,6 +394,11 @@ static inline int dev_pm_genpd_rpm_always_on(struct device *dev, bool on) return -EOPNOTSUPP; } +static inline bool dev_pm_genpd_is_on(struct device *dev) +{ + return false; +} + #define simple_qos_governor (*(struct dev_power_governor *)(NULL)) #define pm_domain_always_on_gov (*(struct dev_power_governor *)(NULL)) #endif
--
2.39.5