[PATCH v3 1/4] driver core: Add dev_set_drv_sync_state()

[Saravana Kannan <saravanak@google.com>]

This can be used by frameworks to set the sync_state() helper functions
for drivers that don't already have them set.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
 include/linux/device.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/device.h b/include/linux/device.h
index 15460a5ac024..2f56afdd9107 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -806,6 +806,18 @@ static inline bool dev_has_sync_state(struct device *dev)
 	return false;
 }
 
+static inline int dev_set_drv_sync_state(struct device *dev,
+					 void (*fn)(struct device *dev))
+{
+	if (!dev || !dev->driver)
+		return 0;
+	if (dev->driver->sync_state && dev->driver->sync_state != fn)
+		return -EBUSY;
+	if (!dev->driver->sync_state)
+		dev->driver->sync_state = fn;
+	return 0;
+}
+
 /*
  * High level routines for use by the bus drivers
  */
-- 
2.28.0.rc0.105.gf9edc3c819-goog