PM / Domains: Export of_genpd_get_from_provider function

This function looks up a PM domain form the provider. This will be
useful to add parent/child domain relationship from the SoC specific
code. The caller of the function must make sure that PM domain provider
is already registered.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 5d7b754..1bd119e 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2108,7 +2108,7 @@
  * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
  * on failure.
  */
-static struct generic_pm_domain *of_genpd_get_from_provider(
+struct generic_pm_domain *of_genpd_get_from_provider(
 					struct of_phandle_args *genpdspec)
 {
 	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
@@ -2128,6 +2128,7 @@
 
 	return genpd;
 }
+EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
 
 /**
  * genpd_dev_pm_detach - Detach a device from its PM domain.
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 1dd6c7f..ba7ca54 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -275,6 +275,8 @@
 int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
 			void *data);
 void of_genpd_del_provider(struct device_node *np);
+struct generic_pm_domain *of_genpd_get_from_provider(
+			struct of_phandle_args *genpdspec);
 
 struct generic_pm_domain *__of_genpd_xlate_simple(
 					struct of_phandle_args *genpdspec,
@@ -292,6 +294,12 @@
 }
 static inline void of_genpd_del_provider(struct device_node *np) {}
 
+static inline struct generic_pm_domain *of_genpd_get_from_provider(
+			struct of_phandle_args *genpdspec)
+{
+	return NULL;
+}
+
 #define __of_genpd_xlate_simple		NULL
 #define __of_genpd_xlate_onecell	NULL