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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.c129
1 files changed, 57 insertions, 72 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 35a26a3e5f6..d3575f5ec6d 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -118,9 +118,11 @@ 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;
+static bool init_cpufreq_transition_notifier_list_called;
static int __init init_cpufreq_transition_notifier_list(void)
{
srcu_init_notifier_head(&cpufreq_transition_notifier_list);
+ init_cpufreq_transition_notifier_list_called = true;
return 0;
}
pure_initcall(init_cpufreq_transition_notifier_list);
@@ -216,7 +218,7 @@ static void cpufreq_debug_disable_ratelimit(void)
}
void cpufreq_debug_printk(unsigned int type, const char *prefix,
- const char *fmt, ...)
+ const char *fmt, ...)
{
char s[256];
va_list args;
@@ -378,7 +380,7 @@ static struct cpufreq_governor *__find_governor(const char *str_governor)
/**
* cpufreq_parse_governor - parse a governor string
*/
-static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
+static int cpufreq_parse_governor(char *str_governor, unsigned int *policy,
struct cpufreq_governor **governor)
{
int err = -EINVAL;
@@ -446,7 +448,7 @@ extern struct sysdev_class cpu_sysdev_class;
#define show_one(file_name, object) \
static ssize_t show_##file_name \
-(struct cpufreq_policy * policy, char *buf) \
+(struct cpufreq_policy *policy, char *buf) \
{ \
return sprintf (buf, "%u\n", policy->object); \
}
@@ -465,7 +467,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
*/
#define store_one(file_name, object) \
static ssize_t store_##file_name \
-(struct cpufreq_policy * policy, const char *buf, size_t count) \
+(struct cpufreq_policy *policy, const char *buf, size_t count) \
{ \
unsigned int ret = -EINVAL; \
struct cpufreq_policy new_policy; \
@@ -490,8 +492,8 @@ store_one(scaling_max_freq,max);
/**
* show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
*/
-static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy,
- char *buf)
+static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
+ char *buf)
{
unsigned int cur_freq = __cpufreq_get(policy->cpu);
if (!cur_freq)
@@ -503,8 +505,7 @@ static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy,
/**
* show_scaling_governor - show the current policy for the specified CPU
*/
-static ssize_t show_scaling_governor (struct cpufreq_policy * policy,
- char *buf)
+static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf)
{
if(policy->policy == CPUFREQ_POLICY_POWERSAVE)
return sprintf(buf, "powersave\n");
@@ -519,8 +520,8 @@ static ssize_t show_scaling_governor (struct cpufreq_policy * policy,
/**
* store_scaling_governor - store policy for the specified CPU
*/
-static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
- const char *buf, size_t count)
+static ssize_t store_scaling_governor(struct cpufreq_policy *policy,
+ const char *buf, size_t count)
{
unsigned int ret = -EINVAL;
char str_governor[16];
@@ -554,7 +555,7 @@ static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
/**
* show_scaling_driver - show the cpufreq driver currently loaded
*/
-static ssize_t show_scaling_driver (struct cpufreq_policy * policy, char *buf)
+static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf)
{
return scnprintf(buf, CPUFREQ_NAME_LEN, "%s\n", cpufreq_driver->name);
}
@@ -562,8 +563,8 @@ static ssize_t show_scaling_driver (struct cpufreq_policy * policy, char *buf)
/**
* show_scaling_available_governors - show the available CPUfreq governors
*/
-static ssize_t show_scaling_available_governors (struct cpufreq_policy *policy,
- char *buf)
+static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy,
+ char *buf)
{
ssize_t i = 0;
struct cpufreq_governor *t;
@@ -585,7 +586,7 @@ out:
/**
* show_affected_cpus - show the CPUs affected by each transition
*/
-static ssize_t show_affected_cpus (struct cpufreq_policy * policy, char *buf)
+static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
{
ssize_t i = 0;
unsigned int cpu;
@@ -602,7 +603,7 @@ static ssize_t show_affected_cpus (struct cpufreq_policy * policy, char *buf)
}
static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
- const char *buf, size_t count)
+ const char *buf, size_t count)
{
unsigned int freq = 0;
unsigned int ret;
@@ -651,7 +652,7 @@ define_one_rw(scaling_max_freq);
define_one_rw(scaling_governor);
define_one_rw(scaling_setspeed);
-static struct attribute * default_attrs[] = {
+static struct attribute *default_attrs[] = {
&cpuinfo_min_freq.attr,
&cpuinfo_max_freq.attr,
&scaling_min_freq.attr,
@@ -667,10 +668,10 @@ static struct attribute * default_attrs[] = {
#define to_policy(k) container_of(k,struct cpufreq_policy,kobj)
#define to_attr(a) container_of(a,struct freq_attr,attr)
-static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
+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);
+ struct cpufreq_policy *policy = to_policy(kobj);
+ struct freq_attr *fattr = to_attr(attr);
ssize_t ret = -EINVAL;
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
@@ -691,11 +692,11 @@ no_policy:
return ret;
}
-static ssize_t store(struct kobject * kobj, struct attribute * attr,
- const char * buf, size_t count)
+static ssize_t store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
{
- struct cpufreq_policy * policy = to_policy(kobj);
- struct freq_attr * fattr = to_attr(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);
if (!policy)
@@ -716,9 +717,9 @@ no_policy:
return ret;
}
-static void cpufreq_sysfs_release(struct kobject * kobj)
+static void cpufreq_sysfs_release(struct kobject *kobj)
{
- struct cpufreq_policy * policy = to_policy(kobj);
+ struct cpufreq_policy *policy = to_policy(kobj);
dprintk("last reference is dropped\n");
complete(&policy->kobj_unregister);
}
@@ -740,7 +741,7 @@ static struct kobj_type ktype_cpufreq = {
*
* Adds the cpufreq interface for a CPU device.
*/
-static int cpufreq_add_dev (struct sys_device * sys_dev)
+static int cpufreq_add_dev(struct sys_device *sys_dev)
{
unsigned int cpu = sys_dev->id;
int ret = 0;
@@ -800,7 +801,6 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = cpufreq_driver->init(policy);
if (ret) {
dprintk("initialization failed\n");
- unlock_policy_rwsem_write(cpu);
goto err_out;
}
policy->user_policy.min = policy->cpuinfo.min_freq;
@@ -823,7 +823,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
/* check for existing affected CPUs. They may not be aware
* of it due to CPU Hotplug.
*/
- managed_policy = cpufreq_cpu_get(j);
+ managed_policy = cpufreq_cpu_get(j); // FIXME: Where is this released? What about error paths?
if (unlikely(managed_policy)) {
/* Set proper policy_cpu */
@@ -842,14 +842,11 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = sysfs_create_link(&sys_dev->kobj,
&managed_policy->kobj,
"cpufreq");
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_driver_exit;
- }
cpufreq_debug_enable_ratelimit();
ret = 0;
- unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit; /* call driver->exit() */
}
}
@@ -859,33 +856,26 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
/* prepare interface data */
ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &sys_dev->kobj,
"cpufreq");
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_driver_exit;
- }
+
/* set up files for this cpu device */
drv_attr = cpufreq_driver->attr;
while ((drv_attr) && (*drv_attr)) {
ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_driver_exit;
- }
drv_attr++;
}
- if (cpufreq_driver->get){
+ if (cpufreq_driver->get) {
ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_driver_exit;
- }
}
- if (cpufreq_driver->target){
+ if (cpufreq_driver->target) {
ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_driver_exit;
- }
}
spin_lock_irqsave(&cpufreq_driver_lock, flags);
@@ -907,10 +897,8 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
cpu_sys_dev = get_cpu_sysdev(j);
ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
"cpufreq");
- if (ret) {
- unlock_policy_rwsem_write(cpu);
+ if (ret)
goto err_out_unregister;
- }
}
policy->governor = NULL; /* to assure that the starting sequence is
@@ -950,6 +938,7 @@ err_out_driver_exit:
cpufreq_driver->exit(policy);
err_out:
+ unlock_policy_rwsem_write(cpu);
kfree(policy);
nomem_out:
@@ -967,7 +956,7 @@ module_out:
* Caller should already have policy_rwsem in write mode for this CPU.
* This routine frees the rwsem before returning.
*/
-static int __cpufreq_remove_dev (struct sys_device * sys_dev)
+static int __cpufreq_remove_dev(struct sys_device *sys_dev)
{
unsigned int cpu = sys_dev->id;
unsigned long flags;
@@ -1071,7 +1060,7 @@ static int __cpufreq_remove_dev (struct sys_device * sys_dev)
}
-static int cpufreq_remove_dev (struct sys_device * sys_dev)
+static int cpufreq_remove_dev(struct sys_device *sys_dev)
{
unsigned int cpu = sys_dev->id;
int retval;
@@ -1138,7 +1127,7 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
cpufreq_cpu_put(policy);
}
- return (ret_freq);
+ return ret_freq;
}
EXPORT_SYMBOL(cpufreq_quick_get);
@@ -1149,7 +1138,7 @@ static unsigned int __cpufreq_get(unsigned int cpu)
unsigned int ret_freq = 0;
if (!cpufreq_driver->get)
- return (ret_freq);
+ return ret_freq;
ret_freq = cpufreq_driver->get(cpu);
@@ -1163,7 +1152,7 @@ static unsigned int __cpufreq_get(unsigned int cpu)
}
}
- return (ret_freq);
+ return ret_freq;
}
/**
@@ -1190,7 +1179,7 @@ unsigned int cpufreq_get(unsigned int cpu)
out_policy:
cpufreq_cpu_put(policy);
out:
- return (ret_freq);
+ return ret_freq;
}
EXPORT_SYMBOL(cpufreq_get);
@@ -1199,7 +1188,7 @@ EXPORT_SYMBOL(cpufreq_get);
* cpufreq_suspend - let the low level driver prepare for suspend
*/
-static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
+static int cpufreq_suspend(struct sys_device *sysdev, pm_message_t pmsg)
{
int cpu = sysdev->id;
int ret = 0;
@@ -1221,22 +1210,18 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
return -EINVAL;
/* only handle each CPU group once */
- if (unlikely(cpu_policy->cpu != cpu)) {
- cpufreq_cpu_put(cpu_policy);
- return 0;
- }
+ if (unlikely(cpu_policy->cpu != cpu))
+ goto out;
if (cpufreq_driver->suspend) {
ret = cpufreq_driver->suspend(cpu_policy, pmsg);
if (ret) {
printk(KERN_ERR "cpufreq: suspend failed in ->suspend "
"step on CPU %u\n", cpu_policy->cpu);
- cpufreq_cpu_put(cpu_policy);
- return ret;
+ goto out;
}
}
-
if (cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)
goto out;
@@ -1270,7 +1255,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
out:
cpufreq_cpu_put(cpu_policy);
- return 0;
+ return ret;
}
/**
@@ -1281,7 +1266,7 @@ out:
* 3.) schedule call cpufreq_update_policy() ASAP as interrupts are
* restored.
*/
-static int cpufreq_resume(struct sys_device * sysdev)
+static int cpufreq_resume(struct sys_device *sysdev)
{
int cpu = sysdev->id;
int ret = 0;
@@ -1302,18 +1287,15 @@ static int cpufreq_resume(struct sys_device * sysdev)
return -EINVAL;
/* only handle each CPU group once */
- if (unlikely(cpu_policy->cpu != cpu)) {
- cpufreq_cpu_put(cpu_policy);
- return 0;
- }
+ if (unlikely(cpu_policy->cpu != cpu))
+ goto fail;
if (cpufreq_driver->resume) {
ret = cpufreq_driver->resume(cpu_policy);
if (ret) {
printk(KERN_ERR "cpufreq: resume failed in ->resume "
"step on CPU %u\n", cpu_policy->cpu);
- cpufreq_cpu_put(cpu_policy);
- return ret;
+ goto fail;
}
}
@@ -1353,6 +1335,7 @@ static int cpufreq_resume(struct sys_device * sysdev)
out:
schedule_work(&cpu_policy->update);
+fail:
cpufreq_cpu_put(cpu_policy);
return ret;
}
@@ -1386,6 +1369,8 @@ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
{
int ret;
+ WARN_ON(!init_cpufreq_transition_notifier_list_called);
+
switch (list) {
case CPUFREQ_TRANSITION_NOTIFIER:
ret = srcu_notifier_chain_register(
@@ -1848,7 +1833,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
cpufreq_debug_enable_ratelimit();
}
- return (ret);
+ return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_register_driver);