[CPUFREQ] Refactor locking in cpufreq_add_dev
[safe/jmp/linux-2.6] / drivers / cpufreq / cpufreq.c
index f7b9d6f..be78c07 100644 (file)
@@ -216,7 +216,7 @@ 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;
@@ -287,7 +287,7 @@ static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
        if (!l_p_j_ref_freq) {
                l_p_j_ref = loops_per_jiffy;
                l_p_j_ref_freq = ci->old;
-               dprintk("saving %lu as reference value for loops_per_jiffy;"
+               dprintk("saving %lu as reference value for loops_per_jiffy; "
                        "freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
        }
        if ((val == CPUFREQ_PRECHANGE  && ci->old < ci->new) ||
@@ -295,7 +295,7 @@ static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
            (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
                loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
                                                                ci->new);
-               dprintk("scaling loops_per_jiffy to %lu"
+               dprintk("scaling loops_per_jiffy to %lu "
                        "for frequency %u kHz\n", loops_per_jiffy, ci->new);
        }
 }
@@ -378,7 +378,7 @@ 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 +446,7 @@ 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 +465,7 @@ 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 +490,8 @@ 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 +503,7 @@ 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 +518,8 @@ 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 +553,7 @@ 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 +561,8 @@ 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 +584,7 @@ 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;
@@ -601,6 +600,31 @@ static ssize_t show_affected_cpus (struct cpufreq_policy * policy, char *buf)
        return i;
 }
 
+static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
+                                       const char *buf, size_t count)
+{
+       unsigned int freq = 0;
+       unsigned int ret;
+
+       if (!policy->governor->store_setspeed)
+               return -EINVAL;
+
+       ret = sscanf(buf, "%u", &freq);
+       if (ret != 1)
+               return -EINVAL;
+
+       policy->governor->store_setspeed(policy, freq);
+
+       return count;
+}
+
+static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
+{
+       if (!policy->governor->show_setspeed)
+               return sprintf(buf, "<unsupported>\n");
+
+       return policy->governor->show_setspeed(policy, buf);
+}
 
 #define define_one_ro(_name) \
 static struct freq_attr _name = \
@@ -624,8 +648,9 @@ define_one_ro(affected_cpus);
 define_one_rw(scaling_min_freq);
 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,
@@ -634,23 +659,24 @@ static struct attribute * default_attrs[] = {
        &scaling_governor.attr,
        &scaling_driver.attr,
        &scaling_available_governors.attr,
+       &scaling_setspeed.attr,
        NULL
 };
 
 #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);
-       ssize_t ret;
+       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)
-               return -EINVAL;
+               goto no_policy;
 
        if (lock_policy_rwsem_read(policy->cpu) < 0)
-               return -EINVAL;
+               goto fail;
 
        if (fattr->show)
                ret = fattr->show(policy, buf);
@@ -658,23 +684,24 @@ static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
                ret = -EIO;
 
        unlock_policy_rwsem_read(policy->cpu);
-
+fail:
        cpufreq_cpu_put(policy);
+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);
-       ssize_t ret;
+       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)
-               return -EINVAL;
+               goto no_policy;
 
        if (lock_policy_rwsem_write(policy->cpu) < 0)
-               return -EINVAL;
+               goto fail;
 
        if (fattr->store)
                ret = fattr->store(policy, buf, count);
@@ -682,14 +709,15 @@ static ssize_t store(struct kobject * kobj, struct attribute * attr,
                ret = -EIO;
 
        unlock_policy_rwsem_write(policy->cpu);
-
+fail:
        cpufreq_cpu_put(policy);
+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);
 }
@@ -711,7 +739,7 @@ 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;
@@ -771,7 +799,6 @@ 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;
@@ -794,7 +821,7 @@ 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 */
@@ -813,14 +840,11 @@ 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() */
                }
        }
@@ -828,15 +852,11 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
        memcpy(&new_policy, policy, sizeof(struct cpufreq_policy));
 
        /* prepare interface data */
-       policy->kobj.parent = &sys_dev->kobj;
-       policy->kobj.ktype = &ktype_cpufreq;
-       strlcpy(policy->kobj.name, "cpufreq", KOBJ_NAME_LEN);
-
-       ret = kobject_register(&policy->kobj);
-       if (ret) {
-               unlock_policy_rwsem_write(cpu);
+       ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &sys_dev->kobj,
+                                  "cpufreq");
+       if (ret)
                goto err_out_driver_exit;
-       }
+
        /* set up files for this cpu device */
        drv_attr = cpufreq_driver->attr;
        while ((drv_attr) && (*drv_attr)) {
@@ -845,12 +865,12 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
                        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)
                        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)
                        goto err_out_driver_exit;
@@ -875,10 +895,8 @@ 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
@@ -896,6 +914,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
                goto err_out_unregister;
        }
 
+       kobject_uevent(&policy->kobj, KOBJ_ADD);
        module_put(cpufreq_driver->owner);
        dprintk("initialization complete\n");
        cpufreq_debug_enable_ratelimit();
@@ -909,7 +928,7 @@ err_out_unregister:
                cpufreq_cpu_data[j] = NULL;
        spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
 
-       kobject_unregister(&policy->kobj);
+       kobject_put(&policy->kobj);
        wait_for_completion(&policy->kobj_unregister);
 
 err_out_driver_exit:
@@ -917,6 +936,7 @@ err_out_driver_exit:
                cpufreq_driver->exit(policy);
 
 err_out:
+       unlock_policy_rwsem_write(cpu);
        kfree(policy);
 
 nomem_out:
@@ -934,7 +954,7 @@ 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;
@@ -975,14 +995,6 @@ static int __cpufreq_remove_dev (struct sys_device * sys_dev)
        }
 #endif
 
-
-       if (!kobject_get(&data->kobj)) {
-               spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
-               cpufreq_debug_enable_ratelimit();
-               unlock_policy_rwsem_write(cpu);
-               return -EFAULT;
-       }
-
 #ifdef CONFIG_SMP
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -1026,8 +1038,6 @@ static int __cpufreq_remove_dev (struct sys_device * sys_dev)
 
        unlock_policy_rwsem_write(cpu);
 
-       kobject_unregister(&data->kobj);
-
        kobject_put(&data->kobj);
 
        /* we need to make sure that the underlying kobj is actually
@@ -1048,7 +1058,7 @@ 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;
@@ -1115,7 +1125,7 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
                cpufreq_cpu_put(policy);
        }
 
-       return (ret_freq);
+       return ret_freq;
 }
 EXPORT_SYMBOL(cpufreq_quick_get);
 
@@ -1126,7 +1136,7 @@ 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);
 
@@ -1140,7 +1150,7 @@ static unsigned int __cpufreq_get(unsigned int cpu)
                }
        }
 
-       return (ret_freq);
+       return ret_freq;
 }
 
 /**
@@ -1167,7 +1177,7 @@ unsigned int cpufreq_get(unsigned int cpu)
 out_policy:
        cpufreq_cpu_put(policy);
 out:
-       return (ret_freq);
+       return ret_freq;
 }
 EXPORT_SYMBOL(cpufreq_get);
 
@@ -1176,7 +1186,7 @@ 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;
@@ -1198,22 +1208,18 @@ 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;
 
@@ -1247,7 +1253,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
 
 out:
        cpufreq_cpu_put(cpu_policy);
-       return 0;
+       return ret;
 }
 
 /**
@@ -1258,7 +1264,7 @@ 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;
@@ -1279,18 +1285,15 @@ 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;
                }
        }
 
@@ -1311,7 +1314,7 @@ static int cpufreq_resume(struct sys_device * sysdev)
                        struct cpufreq_freqs freqs;
 
                        if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
-                               dprintk("Warning: CPU frequency"
+                               dprintk("Warning: CPU frequency "
                                       "is %u, cpufreq assumed %u kHz.\n",
                                       cur_freq, cpu_policy->cur);
 
@@ -1330,6 +1333,7 @@ static int cpufreq_resume(struct sys_device * sysdev)
 
 out:
        schedule_work(&cpu_policy->update);
+fail:
        cpufreq_cpu_put(cpu_policy);
        return ret;
 }
@@ -1602,7 +1606,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
        memcpy(&policy->cpuinfo, &data->cpuinfo,
                                sizeof(struct cpufreq_cpuinfo));
 
-       if (policy->min > data->min && policy->min > policy->max) {
+       if (policy->min > data->max || policy->max < data->min) {
                ret = -EINVAL;
                goto error_out;
        }
@@ -1754,7 +1758,7 @@ static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb,
        return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata cpufreq_cpu_notifier =
+static struct notifier_block __refdata cpufreq_cpu_notifier =
 {
     .notifier_call = cpufreq_cpu_callback,
 };
@@ -1825,7 +1829,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
                cpufreq_debug_enable_ratelimit();
        }
 
-       return (ret);
+       return ret;
 }
 EXPORT_SYMBOL_GPL(cpufreq_register_driver);