pmdomain: core: constify of_phandle_args in add device and subdomain

Pointer to of_phandle_args is not modified by of_genpd_add_device() and
of_genpd_add_subdomain(), so it can be made pointer to const for code
safety and readability.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240208202822.631449-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: krzk

drivers/pmdomain/core.c

@@ -2526,7 +2526,7 @@ EXPORT_SYMBOL_GPL(of_genpd_del_provider);
  * on failure.
  */
 static struct generic_pm_domain *genpd_get_from_provider(
-					struct of_phandle_args *genpdspec)
+					const struct of_phandle_args *genpdspec)
 {
 	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
 	struct of_genpd_provider *provider;
@@ -2557,7 +2557,7 @@ static struct generic_pm_domain *genpd_get_from_provider(
  * Looks-up an I/O PM domain based upon phandle args provided and adds
  * the device to the PM domain. Returns a negative error code on failure.
  */
-int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
+int of_genpd_add_device(const struct of_phandle_args *genpdspec, struct device *dev)
 {
 	struct generic_pm_domain *genpd;
 	int ret;
@@ -2591,8 +2591,8 @@ EXPORT_SYMBOL_GPL(of_genpd_add_device);
  * provided and adds the subdomain to the parent PM domain. Returns a
  * negative error code on failure.
  */
-int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
-			   struct of_phandle_args *subdomain_spec)
+int of_genpd_add_subdomain(const struct of_phandle_args *parent_spec,
+			   const struct of_phandle_args *subdomain_spec)
 {
 	struct generic_pm_domain *parent, *subdomain;
 	int ret;
@@ -2629,8 +2629,8 @@ EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
  * provided and removes the subdomain from the parent PM domain. Returns a
  * negative error code on failure.
  */
-int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
-			      struct of_phandle_args *subdomain_spec)
+int of_genpd_remove_subdomain(const struct of_phandle_args *parent_spec,
+			      const struct of_phandle_args *subdomain_spec)
 {
 	struct generic_pm_domain *parent, *subdomain;
 	int ret;

include/linux/pm_domain.h

@@ -364,11 +364,11 @@ int of_genpd_add_provider_simple(struct device_node *np,
 int of_genpd_add_provider_onecell(struct device_node *np,
 				  struct genpd_onecell_data *data);
 void of_genpd_del_provider(struct device_node *np);
-int of_genpd_add_device(struct of_phandle_args *args, struct device *dev);
-int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
-			   struct of_phandle_args *subdomain_spec);
-int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
-			      struct of_phandle_args *subdomain_spec);
+int of_genpd_add_device(const struct of_phandle_args *args, struct device *dev);
+int of_genpd_add_subdomain(const struct of_phandle_args *parent_spec,
+			   const struct of_phandle_args *subdomain_spec);
+int of_genpd_remove_subdomain(const struct of_phandle_args *parent_spec,
+			      const struct of_phandle_args *subdomain_spec);
 struct generic_pm_domain *of_genpd_remove_last(struct device_node *np);
 int of_genpd_parse_idle_states(struct device_node *dn,
 			       struct genpd_power_state **states, int *n);
@@ -393,20 +393,20 @@ static inline int of_genpd_add_provider_onecell(struct device_node *np,
 
 static inline void of_genpd_del_provider(struct device_node *np) {}
 
-static inline int of_genpd_add_device(struct of_phandle_args *args,
+static inline int of_genpd_add_device(const struct of_phandle_args *args,
 				      struct device *dev)
 {
 	return -ENODEV;
 }
 
-static inline int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
-					 struct of_phandle_args *subdomain_spec)
+static inline int of_genpd_add_subdomain(const struct of_phandle_args *parent_spec,
+					 const struct of_phandle_args *subdomain_spec)
 {
 	return -ENODEV;
 }
 
-static inline int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
-					struct of_phandle_args *subdomain_spec)
+static inline int of_genpd_remove_subdomain(const struct of_phandle_args *parent_spec,
+					    const struct of_phandle_args *subdomain_spec)
 {
 	return -ENODEV;
 }