cpuidle: Make cpuidle_enable_device() call poll_idle_init()

[mv-sheeva.git] / drivers / cpuidle / cpuidle.c

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index dbefe15bd582804497cbca76b6f3ce4fae6e28da..97df791c74cbd75c0044950099a72d3a6de6d5f1 100644 (file)
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -74,6 +74,17 @@ static void cpuidle_idle_call(void)
         */
        hrtimer_peek_ahead_timers();
 #endif
+
+       /*
+        * Call the device's prepare function before calling the
+        * governor's select function.  ->prepare gives the device's
+        * cpuidle driver a chance to update any dynamic information
+        * of its cpuidle states for the current idle period, e.g.
+        * state availability, latencies, residencies, etc.
+        */
+       if (dev->prepare)
+               dev->prepare(dev);
+
        /* ask the governor for the next state */
        next_state = cpuidle_curr_governor->select(dev);
        if (need_resched()) {
@@ -143,6 +154,45 @@ void cpuidle_resume_and_unlock(void)
 
 EXPORT_SYMBOL_GPL(cpuidle_resume_and_unlock);
 
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st)
+{
+       ktime_t t1, t2;
+       s64 diff;
+       int ret;
+
+       t1 = ktime_get();
+       local_irq_enable();
+       while (!need_resched())
+               cpu_relax();
+
+       t2 = ktime_get();
+       diff = ktime_to_us(ktime_sub(t2, t1));
+       if (diff > INT_MAX)
+               diff = INT_MAX;
+
+       ret = (int) diff;
+       return ret;
+}
+
+static void poll_idle_init(struct cpuidle_device *dev)
+{
+       struct cpuidle_state *state = &dev->states[0];
+
+       cpuidle_set_statedata(state, NULL);
+
+       snprintf(state->name, CPUIDLE_NAME_LEN, "C0");
+       snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
+       state->exit_latency = 0;
+       state->target_residency = 0;
+       state->power_usage = -1;
+       state->flags = CPUIDLE_FLAG_POLL;
+       state->enter = poll_idle;
+}
+#else
+static void poll_idle_init(struct cpuidle_device *dev) {}
+#endif /* CONFIG_ARCH_HAS_CPU_RELAX */
+
 /**
  * cpuidle_enable_device - enables idle PM for a CPU
  * @dev: the CPU
@@ -167,6 +217,8 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
                        return ret;
        }
 
+       poll_idle_init(dev);
+
        if ((ret = cpuidle_add_state_sysfs(dev)))
                return ret;
 
@@ -221,45 +273,6 @@ void cpuidle_disable_device(struct cpuidle_device *dev)
 
 EXPORT_SYMBOL_GPL(cpuidle_disable_device);
 
-#ifdef CONFIG_ARCH_HAS_CPU_RELAX
-static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st)
-{
-       ktime_t t1, t2;
-       s64 diff;
-       int ret;
-
-       t1 = ktime_get();
-       local_irq_enable();
-       while (!need_resched())
-               cpu_relax();
-
-       t2 = ktime_get();
-       diff = ktime_to_us(ktime_sub(t2, t1));
-       if (diff > INT_MAX)
-               diff = INT_MAX;
-
-       ret = (int) diff;
-       return ret;
-}
-
-static void poll_idle_init(struct cpuidle_device *dev)
-{
-       struct cpuidle_state *state = &dev->states[0];
-
-       cpuidle_set_statedata(state, NULL);
-
-       snprintf(state->name, CPUIDLE_NAME_LEN, "C0");
-       snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
-       state->exit_latency = 0;
-       state->target_residency = 0;
-       state->power_usage = -1;
-       state->flags = CPUIDLE_FLAG_POLL;
-       state->enter = poll_idle;
-}
-#else
-static void poll_idle_init(struct cpuidle_device *dev) {}
-#endif /* CONFIG_ARCH_HAS_CPU_RELAX */
-
 /**
  * __cpuidle_register_device - internal register function called before register
  * and enable routines
@@ -280,7 +293,25 @@ static int __cpuidle_register_device(struct cpuidle_device *dev)
 
        init_completion(&dev->kobj_unregister);
 
-       poll_idle_init(dev);
+       /*
+        * cpuidle driver should set the dev->power_specified bit
+        * before registering the device if the driver provides
+        * power_usage numbers.
+        *
+        * For those devices whose ->power_specified is not set,
+        * we fill in power_usage with decreasing values as the
+        * cpuidle code has an implicit assumption that state Cn
+        * uses less power than C(n-1).
+        *
+        * With CONFIG_ARCH_HAS_CPU_RELAX, C0 is already assigned
+        * an power value of -1.  So we use -2, -3, etc, for other
+        * c-states.
+        */
+       if (!dev->power_specified) {
+               int i;
+               for (i = CPUIDLE_DRIVER_STATE_START; i < dev->state_count; i++)
+                       dev->states[i].power_usage = -1 - i;
+       }
 
        per_cpu(cpuidle_devices, dev->cpu) = dev;
        list_add(&dev->device_list, &cpuidle_detected_devices);