[PATCH v2 3/8] thermal: core: Add routines for locking and unlocking thermal zones

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Add thermal_zone_device_lock() and thermal_zone_device_unlock() for
acquiring and releasing the thermal zone lock, respectively.

They will be used by the ACPI thermal driver to protect trip point
temperature updates against races with accesses from elsewhere.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---

v1 -> v2: New patch.

---
 drivers/thermal/thermal_core.c |   13 +++++++++++++
 include/linux/thermal.h        |    2 ++
 2 files changed, 15 insertions(+)

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_core.c
+++ linux-pm/drivers/thermal/thermal_core.c
@@ -497,6 +498,18 @@ void thermal_zone_device_update(struct t
 }
 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 
+void thermal_zone_device_lock(struct thermal_zone_device *tz)
+{
+	mutex_lock(&tz->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_lock);
+
+void thermal_zone_device_unlock(struct thermal_zone_device *tz)
+{
+	mutex_unlock(&tz->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_unlock);
+
 static void thermal_zone_device_check(struct work_struct *work)
 {
 	struct thermal_zone_device *tz = container_of(work, struct
Index: linux-pm/include/linux/thermal.h
===================================================================
--- linux-pm.orig/include/linux/thermal.h
+++ linux-pm/include/linux/thermal.h
@@ -336,6 +336,8 @@ int thermal_zone_unbind_cooling_device(s
 				       struct thermal_cooling_device *);
 void thermal_zone_device_update(struct thermal_zone_device *,
 				enum thermal_notify_event);
+void thermal_zone_device_lock(struct thermal_zone_device *tz);
+void thermal_zone_device_unlock(struct thermal_zone_device *tz);
 
 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
 		void *, const struct thermal_cooling_device_ops *);