Merge branch 'pm-opp'

[mirror_ubuntu-artful-kernel.git] / drivers / base / power / opp.c

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
index eb254497a4944454650fb220e4967f5110cec737..28cd75c535b047f2c4276fed4308fa8159491007 100644 (file)
--- a/drivers/base/power/opp.c
+++ b/drivers/base/power/opp.c
@@ -340,6 +340,34 @@ unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency);
 
+/**
+ * dev_pm_opp_get_suspend_opp() - Get suspend opp
+ * @dev:       device for which we do this operation
+ *
+ * Return: This function returns pointer to the suspend opp if it is
+ * defined and available, otherwise it returns NULL.
+ *
+ * Locking: This function must be called under rcu_read_lock(). opp is a rcu
+ * protected pointer. The reason for the same is that the opp pointer which is
+ * returned will remain valid for use with opp_get_{voltage, freq} only while
+ * under the locked area. The pointer returned must be used prior to unlocking
+ * with rcu_read_unlock() to maintain the integrity of the pointer.
+ */
+struct dev_pm_opp *dev_pm_opp_get_suspend_opp(struct device *dev)
+{
+       struct device_opp *dev_opp;
+
+       opp_rcu_lockdep_assert();
+
+       dev_opp = _find_device_opp(dev);
+       if (IS_ERR(dev_opp) || !dev_opp->suspend_opp ||
+           !dev_opp->suspend_opp->available)
+               return NULL;
+
+       return dev_opp->suspend_opp;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_suspend_opp);
+
 /**
  * dev_pm_opp_get_opp_count() - Get number of opps available in the opp list
  * @dev:       device for which we do this operation