Thermal: Remove the cooling_cpufreq_list.

Problem of using this list is that the cpufreq_get_max_state callback will be
called when register cooling device by thermal_cooling_device_register, but
this list isn't ready at this moment. What's more, there is no need to maintain
such a list, we can get cpufreq_cooling_device instance by the private
thermal_cooling_device.devdata.

Signed-off-by: hongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: Francesco Lavra <francescolavra.fl@gmail.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index bfd62b7f32a70ea22f9512e7fd60a3673ccca86e..392d57d8590d40b8de356cd603db5128c991922a 100644 (file)
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -58,8 +58,9 @@ struct cpufreq_cooling_device {
 };
 static LIST_HEAD(cooling_cpufreq_list);
 static DEFINE_IDR(cpufreq_idr);
+static DEFINE_MUTEX(cooling_cpufreq_lock);
 
-static struct mutex cooling_cpufreq_lock;
+static unsigned int cpufreq_dev_count;
 
 /* notify_table passes value to the CPUFREQ_ADJUST callback function. */
 #define NOTIFY_INVALID NULL
@@ -240,28 +241,18 @@ static int cpufreq_thermal_notifier(struct notifier_block *nb,
 static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
                                 unsigned long *state)
 {
-       int ret = -EINVAL, i = 0;
-       struct cpufreq_cooling_device *cpufreq_device;
-       struct cpumask *maskPtr;
+       struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
+       struct cpumask *maskPtr = &cpufreq_device->allowed_cpus;
        unsigned int cpu;
        struct cpufreq_frequency_table *table;
        unsigned long count = 0;
+       int i = 0;
 
-       mutex_lock(&cooling_cpufreq_lock);
-       list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-               if (cpufreq_device && cpufreq_device->cool_dev == cdev)
-                       break;
-       }
-       if (cpufreq_device == NULL)
-               goto return_get_max_state;
-
-       maskPtr = &cpufreq_device->allowed_cpus;
        cpu = cpumask_any(maskPtr);
        table = cpufreq_frequency_get_table(cpu);
        if (!table) {
                *state = 0;
-               ret = 0;
-               goto return_get_max_state;
+               return 0;
        }
 
        for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
@@ -272,12 +263,10 @@ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
 
        if (count > 0) {
                *state = --count;
-               ret = 0;
+               return 0;
        }
 
-return_get_max_state:
-       mutex_unlock(&cooling_cpufreq_lock);
-       return ret;
+       return -EINVAL;
 }
 
 /**
@@ -288,20 +277,10 @@ return_get_max_state:
 static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
                                 unsigned long *state)
 {
-       int ret = -EINVAL;
-       struct cpufreq_cooling_device *cpufreq_device;
+       struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
 
-       mutex_lock(&cooling_cpufreq_lock);
-       list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-               if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
-                       *state = cpufreq_device->cpufreq_state;
-                       ret = 0;
-                       break;
-               }
-       }
-       mutex_unlock(&cooling_cpufreq_lock);
-
-       return ret;
+       *state = cpufreq_device->cpufreq_state;
+       return 0;
 }
 
 /**
@@ -312,22 +291,9 @@ static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
 static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
                                 unsigned long state)
 {
-       int ret = -EINVAL;
-       struct cpufreq_cooling_device *cpufreq_device;
+       struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
 
-       mutex_lock(&cooling_cpufreq_lock);
-       list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-               if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
-                       ret = 0;
-                       break;
-               }
-       }
-       if (!ret)
-               ret = cpufreq_apply_cooling(cpufreq_device, state);
-
-       mutex_unlock(&cooling_cpufreq_lock);
-
-       return ret;
+       return cpufreq_apply_cooling(cpufreq_device, state);
 }
 
 /* Bind cpufreq callbacks to thermal cooling device ops */
@@ -351,14 +317,11 @@ struct thermal_cooling_device *cpufreq_cooling_register(
 {
        struct thermal_cooling_device *cool_dev;
        struct cpufreq_cooling_device *cpufreq_dev = NULL;
-       unsigned int cpufreq_dev_count = 0, min = 0, max = 0;
+       unsigned int min = 0, max = 0;
        char dev_name[THERMAL_NAME_LENGTH];
        int ret = 0, i;
        struct cpufreq_policy policy;
 
-       list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node)
-               cpufreq_dev_count++;
-
        /*Verify that all the clip cpus have same freq_min, freq_max limit*/
        for_each_cpu(i, clip_cpus) {
                /*continue if cpufreq policy not found and not return error*/
@@ -380,9 +343,6 @@ struct thermal_cooling_device *cpufreq_cooling_register(
 
        cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
 
-       if (cpufreq_dev_count == 0)
-               mutex_init(&cooling_cpufreq_lock);
-
        ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
        if (ret) {
                kfree(cpufreq_dev);
@@ -401,12 +361,12 @@ struct thermal_cooling_device *cpufreq_cooling_register(
        cpufreq_dev->cool_dev = cool_dev;
        cpufreq_dev->cpufreq_state = 0;
        mutex_lock(&cooling_cpufreq_lock);
-       list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list);
 
        /* Register the notifier for first cpufreq cooling device */
        if (cpufreq_dev_count == 0)
                cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
                                                CPUFREQ_POLICY_NOTIFIER);
+       cpufreq_dev_count++;
 
        mutex_unlock(&cooling_cpufreq_lock);
        return cool_dev;
@@ -419,33 +379,20 @@ EXPORT_SYMBOL(cpufreq_cooling_register);
  */
 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
 {
-       struct cpufreq_cooling_device *cpufreq_dev = NULL;
-       unsigned int cpufreq_dev_count = 0;
+       struct cpufreq_cooling_device *cpufreq_dev = cdev->devdata;
 
        mutex_lock(&cooling_cpufreq_lock);
-       list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) {
-               if (cpufreq_dev && cpufreq_dev->cool_dev == cdev)
-                       break;
-               cpufreq_dev_count++;
-       }
-
-       if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) {
-               mutex_unlock(&cooling_cpufreq_lock);
-               return;
-       }
-
-       list_del(&cpufreq_dev->node);
+       cpufreq_dev_count--;
 
        /* Unregister the notifier for the last cpufreq cooling device */
-       if (cpufreq_dev_count == 1) {
+       if (cpufreq_dev_count == 0) {
                cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
                                        CPUFREQ_POLICY_NOTIFIER);
        }
        mutex_unlock(&cooling_cpufreq_lock);
+
        thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
        release_idr(&cpufreq_idr, cpufreq_dev->id);
-       if (cpufreq_dev_count == 1)
-               mutex_destroy(&cooling_cpufreq_lock);
        kfree(cpufreq_dev);
 }
 EXPORT_SYMBOL(cpufreq_cooling_unregister);