PM / OPP: Add helpers for initializing CPU OPPs

With "operating-points-v2" its possible to tell which devices share
OPPs. We already have infrastructure to decode that information.

This patch adds following APIs:
 - of_get_cpus_sharing_opps: Returns cpumask of CPUs sharing OPPs (only
   valid with v2 bindings).
 - of_cpumask_init_opp_table: Initializes OPPs for all CPUs present in
   cpumask.
 - of_cpumask_free_opp_table: Frees OPPs for all CPUs present in cpumask.

 - set_cpus_sharing_opps: Sets which CPUs share OPPs (only valid with old
   OPP bindings, as this information isn't present in DT).

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 20324b5..bb52fae 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -121,6 +121,10 @@
 #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)
 int of_init_opp_table(struct device *dev);
 void of_free_opp_table(struct device *dev);
+int of_cpumask_init_opp_table(cpumask_var_t cpumask);
+void of_cpumask_free_opp_table(cpumask_var_t cpumask);
+int of_get_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask);
+int set_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask);
 #else
 static inline int of_init_opp_table(struct device *dev)
 {
@@ -130,6 +134,25 @@
 static inline void of_free_opp_table(struct device *dev)
 {
 }
+
+static inline int of_cpumask_init_opp_table(cpumask_var_t cpumask)
+{
+	return -ENOSYS;
+}
+
+static inline void of_cpumask_free_opp_table(cpumask_var_t cpumask)
+{
+}
+
+static inline int of_get_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+	return -ENOSYS;
+}
+
+static inline int set_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+	return -ENOSYS;
+}
 #endif
 
 #endif		/* __LINUX_OPP_H__ */