1 files changed, 64 insertions, 0 deletions

diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
index 83d978743659..a9a409b2d25c 100644
--- a/drivers/pmdomain/core.c
+++ b/drivers/pmdomain/core.c
@@ -588,6 +588,68 @@ void dev_pm_genpd_synced_poweroff(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff);
 
+/**
+ * dev_pm_genpd_set_hwmode() - Set the HW mode for the device and its PM domain.
+ *
+ * @dev: Device for which the HW-mode should be changed.
+ * @enable: Value to set or unset the HW-mode.
+ *
+ * Some PM domains can rely on HW signals to control the power for a device. To
+ * allow a consumer driver to switch the behaviour for its device in runtime,
+ * which may be beneficial from a latency or energy point of view, this function
+ * may be called.
+ *
+ * It is assumed that the users guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Return: Returns 0 on success and negative error values on failures.
+ */
+int dev_pm_genpd_set_hwmode(struct device *dev, bool enable)
+{
+	struct generic_pm_domain *genpd;
+	int ret = 0;
+
+	genpd = dev_to_genpd_safe(dev);
+	if (!genpd)
+		return -ENODEV;
+
+	if (!genpd->set_hwmode_dev)
+		return -EOPNOTSUPP;
+
+	genpd_lock(genpd);
+
+	if (dev_gpd_data(dev)->hw_mode == enable)
+		goto out;
+
+	ret = genpd->set_hwmode_dev(genpd, dev, enable);
+	if (!ret)
+		dev_gpd_data(dev)->hw_mode = enable;
+
+out:
+	genpd_unlock(genpd);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_set_hwmode);
+
+/**
+ * dev_pm_genpd_get_hwmode() - Get the HW mode setting for the device.
+ *
+ * @dev: Device for which the current HW-mode setting should be fetched.
+ *
+ * This helper function allows consumer drivers to fetch the current HW mode
+ * setting of its the device.
+ *
+ * It is assumed that the users guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Return: Returns the HW mode setting of device from SW cached hw_mode.
+ */
+bool dev_pm_genpd_get_hwmode(struct device *dev)
+{
+	return dev_gpd_data(dev)->hw_mode;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_get_hwmode);
+
 static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 {
 	unsigned int state_idx = genpd->state_idx;
@@ -1687,6 +1749,8 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 
 	gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
 
+	gpd_data->hw_mode = genpd->get_hwmode_dev ? genpd->get_hwmode_dev(genpd, dev) : false;
+
 	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
 	if (ret)
 		goto out;