PM / OPP: Add dev_pm_opp_get_sharing_cpus()

OPP core allows a platform to mark OPP table as shared, when the
platform isn't using operating-points-v2 bindings.

And, so there should be a non DT way of finding out if the OPP table is
shared or not.

This patch adds dev_pm_opp_get_sharing_cpus(), which first tries to get
OPP sharing information from the opp-table (in case it is already marked
as shared), otherwise it uses the existing DT way of finding sharing
information.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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 0c08ed3..15f5544 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -66,6 +66,7 @@
 void dev_pm_opp_put_regulator(struct device *dev);
 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);
 int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const cpumask_var_t cpumask);
+int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask);
 #else
 static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
 {
@@ -184,6 +185,11 @@
 	return -ENOTSUPP;
 }
 
+static inline int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+	return -EINVAL;
+}
+
 #endif		/* CONFIG_PM_OPP */
 
 #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)