[PATCH RFC 07/10] PM / wakeup : Introduce device_child_may_wakeup

[srinivas.kandagatla at st.com]

From: Srinivas Kandagatla <srinivas.kandagatla at st.com>

This patch introduces device_child_may_wakeup function, which will be
useful for wrapper or SoC level driver power management code.
Without this patch each driver has to write this same code to get the
functionality.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla at st.com>
---
 drivers/base/power/wakeup.c |   23 +++++++++++++++++++++++
 include/linux/pm_wakeup.h   |    1 +
 2 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 2d56f41..270f000 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -342,6 +342,29 @@ int device_set_wakeup_enable(struct device *dev, bool enable)
 }
 EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
 
+/* callback for device_child_may_wakeup */
+static int __device_child_may_wakeup(struct device *dev, void *c)
+{
+	return device_may_wakeup(dev);
+}
+
+/**
+ * device_child_may_wakeup - Check if any of the child devices are wakeup
+ * sources.
+ * @dev: parent device to handle.
+ *
+ * Function to check if any of the children of a given parent are wakeup
+ * sources.
+ *
+ * This function will return true if any one of the children of given parent
+ * are wakeup sources, else it returns false.
+ */
+bool device_child_may_wakeup(struct device *parent)
+{
+	return device_for_each_child(parent, NULL, __device_child_may_wakeup);
+}
+EXPORT_SYMBOL_GPL(device_child_may_wakeup);
+
 /*
  * The functions below use the observation that each wakeup event starts a
  * period in which the system should not be suspended.  The moment this period
diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
index a0f7080..b376584 100644
--- a/include/linux/pm_wakeup.h
+++ b/include/linux/pm_wakeup.h
@@ -93,6 +93,7 @@ extern int device_wakeup_disable(struct device *dev);
 extern void device_set_wakeup_capable(struct device *dev, bool capable);
 extern int device_init_wakeup(struct device *dev, bool val);
 extern int device_set_wakeup_enable(struct device *dev, bool enable);
+bool device_child_may_wakeup(struct device *parent);
 extern void __pm_stay_awake(struct wakeup_source *ws);
 extern void pm_stay_awake(struct device *dev);
 extern void __pm_relax(struct wakeup_source *ws);
-- 
1.7.6.5