[PATCH] cpuidle: change #ifdef for the declaration of cpuidle_enter_s2idle()

[zhuguangqing83]

From: zhuguangqing <zhuguangqing@xxxxxxxxxx>

Currently, if CONFIG_SUSPEND=n and CONFIG_CPU_IDLE=y, the function
cpuidle_enter_s2idle() is declared but not defined, it may cause error
when cpuidle_enter_s2idle() is called.

If CONFIG_SUSPEND=y and CONFIG_CPU_IDLE=n, the function
cpuidle_enter_s2idle() is defined as "return -ENODEV;" which is not
supposed to be.

Change #ifdef CONFIG_CPU_IDLE to #ifdef CONFIG_SUSPEND for
cpuidle_enter_s2idle() in cpuidle.h, which is consistent with its
defination in cpuidle.c.

Signed-off-by: zhuguangqing <zhuguangqing@xxxxxxxxxx>
---
 include/linux/cpuidle.h | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index 6175c77bf25e..2aa8cead1727 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -216,22 +216,26 @@ static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; }
 extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
 				      struct cpuidle_device *dev,
 				      u64 latency_limit_ns);
-extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv,
-				struct cpuidle_device *dev);
 extern void cpuidle_use_deepest_state(u64 latency_limit_ns);
 #else
 static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
 					     struct cpuidle_device *dev,
 					     u64 latency_limit_ns)
 {return -ENODEV; }
-static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv,
-				       struct cpuidle_device *dev)
-{return -ENODEV; }
 static inline void cpuidle_use_deepest_state(u64 latency_limit_ns)
 {
 }
 #endif
 
+#ifdef CONFIG_SUSPEND
+extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv,
+				struct cpuidle_device *dev);
+#else
+static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv,
+				       struct cpuidle_device *dev)
+{return -ENODEV; }
+#endif
+
 /* kernel/sched/idle.c */
 extern void sched_idle_set_state(struct cpuidle_state *idle_state);
 extern void default_idle_call(void);
-- 
2.17.1