cpuidle: stop depending on pm_idle

cpuidle users should call cpuidle_call_idle() directly
rather than via (pm_idle)() function pointer.

Architecture may choose to continue using (pm_idle)(),
but cpuidle need not depend on it:

  my_arch_cpu_idle()
	...
	if(cpuidle_call_idle())
		pm_idle();

cc: Kevin Hilman <khilman@deeprootsystems.com>
cc: Paul Mundt <lethal@linux-sh.org>
cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 18 insertions, 20 deletions

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 041df0b056b..d4c54237288 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -25,10 +25,10 @@ DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
 
 DEFINE_MUTEX(cpuidle_lock);
 LIST_HEAD(cpuidle_detected_devices);
-static void (*pm_idle_old)(void);
 
 static int enabled_devices;
 static int off __read_mostly;
+static int initialized __read_mostly;
 
 int cpuidle_disabled(void)
 {
@@ -56,25 +56,23 @@ static int __cpuidle_register_device(struct cpuidle_device *dev);
  * cpuidle_idle_call - the main idle loop
  *
  * NOTE: no locks or semaphores should be used here
+ * return non-zero on failure
  */
-static void cpuidle_idle_call(void)
+int cpuidle_idle_call(void)
 {
         struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
         struct cpuidle_state *target_state;
         int next_state;
 
+        if (off)
+                return -ENODEV;
+
+        if (!initialized)
+                return -ENODEV;
+
         /* check if the device is ready */
-        if (!dev || !dev->enabled) {
-                if (pm_idle_old)
-                        pm_idle_old();
-                else
-#if defined(CONFIG_ARCH_HAS_DEFAULT_IDLE)
-                        default_idle();
-#else
-                        local_irq_enable();
-#endif
-                return;
-        }
+        if (!dev || !dev->enabled)
+                return -EBUSY;
 
 #if 0
         /* shows regressions, re-enable for 2.6.29 */
@@ -99,7 +97,7 @@ static void cpuidle_idle_call(void)
         next_state = cpuidle_curr_governor->select(dev);
         if (need_resched()) {
                 local_irq_enable();
-                return;
+                return 0;
         }
 
         target_state = &dev->states[next_state];
@@ -124,6 +122,8 @@ static void cpuidle_idle_call(void)
         /* give the governor an opportunity to reflect on the outcome */
         if (cpuidle_curr_governor->reflect)
                 cpuidle_curr_governor->reflect(dev);
+
+        return 0;
 }
 
 /**
@@ -131,10 +131,10 @@ static void cpuidle_idle_call(void)
  */
 void cpuidle_install_idle_handler(void)
 {
-        if (enabled_devices && (pm_idle != cpuidle_idle_call)) {
+        if (enabled_devices) {
                 /* Make sure all changes finished before we switch to new idle */
                 smp_wmb();
-                pm_idle = cpuidle_idle_call;
+                initialized = 1;
         }
 }
 
@@ -143,8 +143,8 @@ void cpuidle_install_idle_handler(void)
  */
 void cpuidle_uninstall_idle_handler(void)
 {
-        if (enabled_devices && pm_idle_old && (pm_idle != pm_idle_old)) {
-                pm_idle = pm_idle_old;
+        if (enabled_devices) {
+                initialized = 0;
                 cpuidle_kick_cpus();
         }
 }
@@ -440,8 +440,6 @@ static int __init cpuidle_init(void)
         if (cpuidle_disabled())
                 return -ENODEV;
 
-        pm_idle_old = pm_idle;
-
         ret = cpuidle_add_class_sysfs(&cpu_sysdev_class);
         if (ret)
                 return ret;