PM / Domains: Convert pm_genpd_init() to return an error code

The are already cases when pm_genpd_init() can fail. Currently we hide the failures instead of propagating an error code, which is a better method. Moreover, to prepare for future changes like moving away from using a fixed array-size of the struct genpd_power_state, to instead dynamically allocate data for it, the pm_genpd_init() API needs to be able to return an error code, as allocation can fail. Current users of the pm_genpd_init() is thus requested to start dealing with error codes. In the transition phase, users will have to live with only error messages being printed to log. Signed-off-by: Ulf Hansson <[email protected]> Acked-by: Kevin Hilman <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
lucamilanesio · Jun 29, 2016 · 7eb231c · 7eb231c
1 parent 122a223
commit 7eb231c
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Showing 2 changed files with 12 additions and 7 deletions.
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
@@ -1258,12 +1258,14 @@ EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
  * @genpd: PM domain object to initialize.
  * @gov: PM domain governor to associate with the domain (may be NULL).
  * @is_off: Initial value of the domain's power_is_off field.
+ *
+ * Returns 0 on successful initialization, else a negative error code.
  */
-void pm_genpd_init(struct generic_pm_domain *genpd,
-		   struct dev_power_governor *gov, bool is_off)
+int pm_genpd_init(struct generic_pm_domain *genpd,
+		  struct dev_power_governor *gov, bool is_off)
 {
 	if (IS_ERR_OR_NULL(genpd))
-		return;
+		return -EINVAL;
 
 	INIT_LIST_HEAD(&genpd->master_links);
 	INIT_LIST_HEAD(&genpd->slave_links);
@@ -1321,6 +1323,8 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
 	mutex_lock(&gpd_list_lock);
 	list_add(&genpd->gpd_list_node, &gpd_list);
 	mutex_unlock(&gpd_list_lock);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(pm_genpd_init);
 

diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
@@ -127,8 +127,8 @@ extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 				  struct generic_pm_domain *new_subdomain);
 extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 				     struct generic_pm_domain *target);
-extern void pm_genpd_init(struct generic_pm_domain *genpd,
-			  struct dev_power_governor *gov, bool is_off);
+extern int pm_genpd_init(struct generic_pm_domain *genpd,
+			 struct dev_power_governor *gov, bool is_off);
 
 extern struct dev_power_governor simple_qos_governor;
 extern struct dev_power_governor pm_domain_always_on_gov;
@@ -163,9 +163,10 @@ static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 {
 	return -ENOSYS;
 }
-static inline void pm_genpd_init(struct generic_pm_domain *genpd,
-				 struct dev_power_governor *gov, bool is_off)
+static inline int pm_genpd_init(struct generic_pm_domain *genpd,
+				struct dev_power_governor *gov, bool is_off)
 {
+	return -ENOSYS;
 }
 #endif