Merge android-4.4-p.198 (dbd0162) into msm-4.4

[sagit-ice-cold/kernel_xiaomi_msm8998.git] / drivers / cpufreq / cpufreq.c

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index d3b2047..e8fca2c 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -131,6 +131,7 @@ static void handle_update(struct work_struct *work);
  */
 static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
 static struct srcu_notifier_head cpufreq_transition_notifier_list;
+struct atomic_notifier_head cpufreq_govinfo_notifier_list;
 
 static bool init_cpufreq_transition_notifier_list_called;
 static int __init init_cpufreq_transition_notifier_list(void)
@@ -141,6 +142,15 @@ static int __init init_cpufreq_transition_notifier_list(void)
 }
 pure_initcall(init_cpufreq_transition_notifier_list);
 
+static bool init_cpufreq_govinfo_notifier_list_called;
+static int __init init_cpufreq_govinfo_notifier_list(void)
+{
+       ATOMIC_INIT_NOTIFIER_HEAD(&cpufreq_govinfo_notifier_list);
+       init_cpufreq_govinfo_notifier_list_called = true;
+       return 0;
+}
+pure_initcall(init_cpufreq_govinfo_notifier_list);
+
 static int off __read_mostly;
 static int cpufreq_disabled(void)
 {
@@ -1099,7 +1109,8 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cp
        if (has_target()) {
                ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
                if (ret) {
-                       pr_err("%s: Failed to stop governor\n", __func__);
+                       pr_err("%s: Failed to stop governor for CPU%u, policy CPU%u\n",
+                              __func__, cpu, policy->cpu);
                        return ret;
                }
        }
@@ -1114,7 +1125,8 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cp
                        ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
 
                if (ret) {
-                       pr_err("%s: Failed to start governor\n", __func__);
+                       pr_err("%s: Failed to start governor for CPU%u, policy CPU%u\n",
+                              __func__, cpu, policy->cpu);
                        return ret;
                }
        }
@@ -1428,7 +1440,8 @@ static void cpufreq_offline_prepare(unsigned int cpu)
        if (has_target()) {
                int ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
                if (ret)
-                       pr_err("%s: Failed to stop governor\n", __func__);
+                       pr_err("%s: Failed to stop governor for CPU%u\n",
+                              __func__, cpu);
        }
 
        down_write(&policy->rwsem);
@@ -1478,7 +1491,8 @@ static void cpufreq_offline_finish(unsigned int cpu)
        if (has_target()) {
                int ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
                if (ret)
-                       pr_err("%s: Failed to exit governor\n", __func__);
+                       pr_err("%s: Failed to start governor for CPU%u, policy CPU%u\n",
+                              __func__, cpu, policy->cpu);
        }
 
        /*
@@ -1807,7 +1821,8 @@ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
        if (cpufreq_disabled())
                return -EINVAL;
 
-       WARN_ON(!init_cpufreq_transition_notifier_list_called);
+       WARN_ON(!init_cpufreq_transition_notifier_list_called ||
+               !init_cpufreq_govinfo_notifier_list_called);
 
        switch (list) {
        case CPUFREQ_TRANSITION_NOTIFIER:
@@ -1818,6 +1833,10 @@ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
                ret = blocking_notifier_chain_register(
                                &cpufreq_policy_notifier_list, nb);
                break;
+       case CPUFREQ_GOVINFO_NOTIFIER:
+               ret = atomic_notifier_chain_register(
+                               &cpufreq_govinfo_notifier_list, nb);
+               break;
        default:
                ret = -EINVAL;
        }
@@ -1852,6 +1871,10 @@ int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
                ret = blocking_notifier_chain_unregister(
                                &cpufreq_policy_notifier_list, nb);
                break;
+       case CPUFREQ_GOVINFO_NOTIFIER:
+               ret = atomic_notifier_chain_unregister(
+                               &cpufreq_govinfo_notifier_list, nb);
+               break;
        default:
                ret = -EINVAL;
        }
@@ -1964,15 +1987,6 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
        pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n",
                 policy->cpu, target_freq, relation, old_target_freq);
 
-       /*
-        * This might look like a redundant call as we are checking it again
-        * after finding index. But it is left intentionally for cases where
-        * exactly same freq is called again and so we can save on few function
-        * calls.
-        */
-       if (target_freq == policy->cur)
-               return 0;
-
        /* Save last value to restore later on errors */
        policy->restore_freq = policy->cur;
 
@@ -2361,6 +2375,9 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb,
 {
        unsigned int cpu = (unsigned long)hcpu;
 
+       if (!cpufreq_driver)
+               return NOTIFY_OK;
+
        switch (action & ~CPU_TASKS_FROZEN) {
        case CPU_ONLINE:
                cpufreq_online(cpu);
@@ -2527,6 +2544,9 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 
        pr_debug("trying to register driver %s\n", driver_data->name);
 
+       /* Register for hotplug notifers before blocking hotplug. */
+       register_hotcpu_notifier(&cpufreq_cpu_notifier);
+
        /* Protect against concurrent CPU online/offline. */
        get_online_cpus();
 
@@ -2559,8 +2579,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
                goto err_if_unreg;
        }
 
-       register_hotcpu_notifier(&cpufreq_cpu_notifier);
-       pr_debug("driver %s up and running\n", driver_data->name);
+       pr_info("driver %s up and running\n", driver_data->name);
 
 out:
        put_online_cpus();
@@ -2593,7 +2612,7 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
        if (!cpufreq_driver || (driver != cpufreq_driver))
                return -EINVAL;
 
-       pr_debug("unregistering driver %s\n", driver->name);
+       pr_info("unregistering driver %s\n", driver->name);
 
        /* Protect against concurrent cpu hotplug */
        get_online_cpus();