The platform code parses the
device tree to find available nodes representing the generic power domain,
instantiates the available domains and initializes them by calling
pm_genpd_init().

Nodes representing the devices include a phandle of the power domain to
which it belongs. As these devices get instantiated, the driver code
checkes for availability of a power domain phandle, converts the phandle
to a device node and uses the new pm_genpd_of_add_device() api to
associate the device with a power domain.

pm_genpd_of_add_device() runs through its list of registered power domains
and matches the OF node of the domain with the one specified as the
parameter. If a match is found, the device is associated with the matched
domain.

Cc: Rafael J. Wysocki <redacted>
Cc: Rob Herring <redacted>
Cc: Grant Likely <redacted>
Signed-off-by: Thomas Abraham <redacted>
---
 drivers/base/power/domain.c |   14 +++++++++++++-
 include/linux/pm_domain.h   |   13 +++++++++++--
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 92e6a90..e895dc9 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c

@@ -1118,14 +1118,26 @@ static void pm_genpd_complete(struct device *dev)
  * @td: Set of PM QoS timing parameters to attach to the device.
  */
 int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
-			  struct gpd_timing_data *td)
+			  struct gpd_timing_data *td, struct device_node *node)
 {
 	struct generic_pm_domain_data *gpd_data;
+	struct generic_pm_domain *gpd = NULL;
 	struct pm_domain_data *pdd;
 	int ret = 0;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
+	mutex_lock(&gpd_list_lock);
+	if (node) {
+		list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+			if (gpd->of_node == node) {
+				genpd = gpd;
+				break;
+			}
+		}
+	}
+	mutex_unlock(&gpd_list_lock);

+
 	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
 		return -EINVAL;
 

diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index a03a0ad..2ce7cc4 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h

@@ -11,6 +11,7 @@
 
 #include <linux/device.h>
 #include <linux/err.h>
+#include <linux/of.h>
 
 enum gpd_status {
 	GPD_STATE_ACTIVE = 0,	/* PM domain is active */

@@ -70,6 +71,7 @@ struct generic_pm_domain {
 	s64 break_even_ns;	/* Power break even for the entire domain. */
 	s64 max_off_time_ns;	/* Maximum allowed "suspended" time. */
 	ktime_t power_off_time;
+	struct device_node *of_node; /* Node in device tree */

 };
 
 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)

@@ -115,12 +117,19 @@ extern struct dev_power_governor simple_qos_governor;
 extern struct generic_pm_domain *dev_to_genpd(struct device *dev);
 extern int __pm_genpd_add_device(struct generic_pm_domain *genpd,
 				 struct device *dev,
-				 struct gpd_timing_data *td);
+				 struct gpd_timing_data *td,
+				 struct device_node *gpd_node);
 
 static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
 				      struct device *dev)
 {
-	return __pm_genpd_add_device(genpd, dev, NULL);
+	return __pm_genpd_add_device(genpd, dev, NULL, NULL);
+}
+
+static inline int pm_genpd_of_add_device(struct device_node *gpd_node,
+					 struct device *dev)
+{
+	return __pm_genpd_add_device(NULL, dev, NULL, gpd_node);
 }
 
 extern int pm_genpd_remove_device(struct generic_pm_domain *genpd,