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path: root/drivers/cpufreq/cpufreq.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r--drivers/cpufreq/cpufreq.c110
1 files changed, 56 insertions, 54 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7a511479ae2..9582de1c9ca 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -35,8 +35,8 @@
* level driver of CPUFreq support, and its spinlock. This lock
* also protects the cpufreq_cpu_data array.
*/
-static struct cpufreq_driver *cpufreq_driver;
-static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
+static struct cpufreq_driver *cpufreq_driver;
+static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
static DEFINE_SPINLOCK(cpufreq_driver_lock);
/* internal prototypes */
@@ -50,15 +50,15 @@ static void handle_update(void *data);
* changes to devices when the CPU clock speed changes.
* The mutex locks both lists.
*/
-static struct notifier_block *cpufreq_policy_notifier_list;
-static struct notifier_block *cpufreq_transition_notifier_list;
-static DECLARE_RWSEM (cpufreq_notifier_rwsem);
+static struct notifier_block *cpufreq_policy_notifier_list;
+static struct notifier_block *cpufreq_transition_notifier_list;
+static DECLARE_RWSEM (cpufreq_notifier_rwsem);
static LIST_HEAD(cpufreq_governor_list);
-static DEFINE_MUTEX (cpufreq_governor_mutex);
+static DEFINE_MUTEX (cpufreq_governor_mutex);
-struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
{
struct cpufreq_policy *data;
unsigned long flags;
@@ -85,20 +85,19 @@ struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
if (!kobject_get(&data->kobj))
goto err_out_put_module;
-
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
-
return data;
- err_out_put_module:
+err_out_put_module:
module_put(cpufreq_driver->owner);
- err_out_unlock:
+err_out_unlock:
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- err_out:
+err_out:
return NULL;
}
EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
+
void cpufreq_cpu_put(struct cpufreq_policy *data)
{
kobject_put(&data->kobj);
@@ -229,44 +228,53 @@ static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) {
/**
- * cpufreq_notify_transition - call notifier chain and adjust_jiffies on frequency transition
+ * cpufreq_notify_transition - call notifier chain and adjust_jiffies
+ * on frequency transition.
*
- * This function calls the transition notifiers and the "adjust_jiffies" function. It is called
- * twice on all CPU frequency changes that have external effects.
+ * This function calls the transition notifiers and the "adjust_jiffies"
+ * function. It is called twice on all CPU frequency changes that have
+ * external effects.
*/
void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
{
+ struct cpufreq_policy *policy;
+
BUG_ON(irqs_disabled());
freqs->flags = cpufreq_driver->flags;
- dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new);
+ dprintk("notification %u of frequency transition to %u kHz\n",
+ state, freqs->new);
down_read(&cpufreq_notifier_rwsem);
+
+ policy = cpufreq_cpu_data[freqs->cpu];
switch (state) {
+
case CPUFREQ_PRECHANGE:
- /* detect if the driver reported a value as "old frequency" which
- * is not equal to what the cpufreq core thinks is "old frequency".
+ /* detect if the driver reported a value as "old frequency"
+ * which is not equal to what the cpufreq core thinks is
+ * "old frequency".
*/
if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cur)) &&
- (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur)))
- {
- dprintk(KERN_WARNING "Warning: CPU frequency is %u, "
- "cpufreq assumed %u kHz.\n", freqs->old, cpufreq_cpu_data[freqs->cpu]->cur);
- freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
+ if ((policy) && (policy->cpu == freqs->cpu) &&
+ (policy->cur) && (policy->cur != freqs->old)) {
+ dprintk(KERN_WARNING "Warning: CPU frequency is"
+ " %u, cpufreq assumed %u kHz.\n",
+ freqs->old, policy->cur);
+ freqs->old = policy->cur;
}
}
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs);
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_PRECHANGE, freqs);
adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
break;
+
case CPUFREQ_POSTCHANGE:
adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_POSTCHANGE, freqs);
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)))
- cpufreq_cpu_data[freqs->cpu]->cur = freqs->new;
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_POSTCHANGE, freqs);
+ if (likely(policy) && likely(policy->cpu == freqs->cpu))
+ policy->cur = freqs->new;
break;
}
up_read(&cpufreq_notifier_rwsem);
@@ -308,7 +316,7 @@ static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
return 0;
}
}
- out:
+out:
mutex_unlock(&cpufreq_governor_mutex);
}
return -EINVAL;
@@ -415,7 +423,6 @@ static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
return -EINVAL;
ret = cpufreq_set_policy(&new_policy);
-
return ret ? ret : count;
}
@@ -446,7 +453,7 @@ static ssize_t show_scaling_available_governors (struct cpufreq_policy * policy,
goto out;
i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
}
- out:
+out:
i += sprintf(&buf[i], "\n");
return i;
}
@@ -789,7 +796,6 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
kfree(data);
cpufreq_debug_enable_ratelimit();
-
return 0;
}
@@ -870,8 +876,7 @@ unsigned int cpufreq_get(unsigned int cpu)
ret = cpufreq_driver->get(cpu);
- if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS))
- {
+ if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
/* verify no discrepancy between actual and saved value exists */
if (unlikely(ret != policy->cur)) {
cpufreq_out_of_sync(cpu, policy->cur, ret);
@@ -881,7 +886,7 @@ unsigned int cpufreq_get(unsigned int cpu)
mutex_unlock(&policy->lock);
- out:
+out:
cpufreq_cpu_put(policy);
return (ret);
@@ -962,7 +967,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
cpu_policy->cur = cur_freq;
}
- out:
+out:
cpufreq_cpu_put(cpu_policy);
return 0;
}
@@ -1169,7 +1174,6 @@ int cpufreq_driver_target(struct cpufreq_policy *policy,
mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
@@ -1208,7 +1212,6 @@ int cpufreq_governor(unsigned int cpu, unsigned int event)
mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_governor);
@@ -1232,7 +1235,6 @@ int cpufreq_register_governor(struct cpufreq_governor *governor)
list_add(&governor->governor_list, &cpufreq_governor_list);
mutex_unlock(&cpufreq_governor_mutex);
-
return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_register_governor);
@@ -1277,7 +1279,6 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
-
return 0;
}
EXPORT_SYMBOL(cpufreq_get_policy);
@@ -1291,9 +1292,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
policy->min, policy->max);
- memcpy(&policy->cpuinfo,
- &data->cpuinfo,
- sizeof(struct cpufreq_cpuinfo));
+ memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo));
/* verify the cpu speed can be set within this limit */
ret = cpufreq_driver->verify(policy);
@@ -1324,8 +1323,8 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
up_read(&cpufreq_notifier_rwsem);
- data->min = policy->min;
- data->max = policy->max;
+ data->min = policy->min;
+ data->max = policy->max;
dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max);
@@ -1362,7 +1361,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
}
- error_out:
+error_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
@@ -1421,9 +1420,7 @@ int cpufreq_update_policy(unsigned int cpu)
mutex_lock(&data->lock);
dprintk("updating policy for CPU %u\n", cpu);
- memcpy(&policy,
- data,
- sizeof(struct cpufreq_policy));
+ memcpy(&policy, data, sizeof(struct cpufreq_policy));
policy.min = data->user_policy.min;
policy.max = data->user_policy.max;
policy.policy = data->user_policy.policy;
@@ -1433,8 +1430,13 @@ int cpufreq_update_policy(unsigned int cpu)
-> ask driver for current freq and notify governors about a change */
if (cpufreq_driver->get) {
policy.cur = cpufreq_driver->get(cpu);
- if (data->cur != policy.cur)
- cpufreq_out_of_sync(cpu, data->cur, policy.cur);
+ if (!data->cur) {
+ dprintk("Driver did not initialize current freq");
+ data->cur = policy.cur;
+ } else {
+ if (data->cur != policy.cur)
+ cpufreq_out_of_sync(cpu, data->cur, policy.cur);
+ }
}
ret = __cpufreq_set_policy(data, &policy);