Merge branch 'pm-cpufreq'

* pm-cpufreq:
  cpufreq: Fix sysfs deadlock with concurrent hotplug/frequency switch
  EXYNOS: bugfix on retrieving old_index from freqs.old

2 files changed, 39 insertions, 10 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7f2f149ae40f..fb8a5279c5d8 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -138,7 +138,7 @@ void disable_cpufreq(void)
 static LIST_HEAD(cpufreq_governor_list);
 static DEFINE_MUTEX(cpufreq_governor_mutex);
 
-struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
+static struct cpufreq_policy *__cpufreq_cpu_get(unsigned int cpu, bool sysfs)
 {
 	struct cpufreq_policy *data;
 	unsigned long flags;
@@ -162,7 +162,7 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
 	if (!data)
 		goto err_out_put_module;
 
-	if (!kobject_get(&data->kobj))
+	if (!sysfs && !kobject_get(&data->kobj))
 		goto err_out_put_module;
 
 	spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
@@ -175,16 +175,35 @@ err_out_unlock:
 err_out:
 	return NULL;
 }
+
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
+{
+	return __cpufreq_cpu_get(cpu, false);
+}
 EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
 
+static struct cpufreq_policy *cpufreq_cpu_get_sysfs(unsigned int cpu)
+{
+	return __cpufreq_cpu_get(cpu, true);
+}
 
-void cpufreq_cpu_put(struct cpufreq_policy *data)
+static void __cpufreq_cpu_put(struct cpufreq_policy *data, bool sysfs)
 {
-	kobject_put(&data->kobj);
+	if (!sysfs)
+		kobject_put(&data->kobj);
 	module_put(cpufreq_driver->owner);
 }
+
+void cpufreq_cpu_put(struct cpufreq_policy *data)
+{
+	__cpufreq_cpu_put(data, false);
+}
 EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
 
+static void cpufreq_cpu_put_sysfs(struct cpufreq_policy *data)
+{
+	__cpufreq_cpu_put(data, true);
+}
 
 /*********************************************************************
  *            EXTERNALLY AFFECTING FREQUENCY CHANGES                 *
@@ -617,7 +636,7 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
 	struct cpufreq_policy *policy = to_policy(kobj);
 	struct freq_attr *fattr = to_attr(attr);
 	ssize_t ret = -EINVAL;
-	policy = cpufreq_cpu_get(policy->cpu);
+	policy = cpufreq_cpu_get_sysfs(policy->cpu);
 	if (!policy)
 		goto no_policy;
 
@@ -631,7 +650,7 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
 
 	unlock_policy_rwsem_read(policy->cpu);
 fail:
-	cpufreq_cpu_put(policy);
+	cpufreq_cpu_put_sysfs(policy);
 no_policy:
 	return ret;
 }
@@ -642,7 +661,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
 	struct cpufreq_policy *policy = to_policy(kobj);
 	struct freq_attr *fattr = to_attr(attr);
 	ssize_t ret = -EINVAL;
-	policy = cpufreq_cpu_get(policy->cpu);
+	policy = cpufreq_cpu_get_sysfs(policy->cpu);
 	if (!policy)
 		goto no_policy;
 
@@ -656,7 +675,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
 
 	unlock_policy_rwsem_write(policy->cpu);
 fail:
-	cpufreq_cpu_put(policy);
+	cpufreq_cpu_put_sysfs(policy);
 no_policy:
 	return ret;
 }
diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
index b243a7ee01f6..af2d81e10f71 100644
--- a/drivers/cpufreq/exynos-cpufreq.c
+++ b/drivers/cpufreq/exynos-cpufreq.c
@@ -62,8 +62,18 @@ static int exynos_target(struct cpufreq_policy *policy,
 		goto out;
 	}
 
-	if (cpufreq_frequency_table_target(policy, freq_table,
-					   freqs.old, relation, &old_index)) {
+	/*
+	 * The policy max have been changed so that we cannot get proper
+	 * old_index with cpufreq_frequency_table_target(). Thus, ignore
+	 * policy and get the index from the raw freqeuncy table.
+	 */
+	for (old_index = 0;
+		freq_table[old_index].frequency != CPUFREQ_TABLE_END;
+		old_index++)
+		if (freq_table[old_index].frequency == freqs.old)
+			break;
+
+	if (freq_table[old_index].frequency == CPUFREQ_TABLE_END) {
 		ret = -EINVAL;
 		goto out;
 	}