/* * linux/drivers/thermal/cpu_cooling.c * * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) * Copyright (C) 2012 Amit Daniel * * Copyright (C) 2014 Viresh Kumar * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include #include #include #include #include #include #include #include #include #include /* * Cooling state <-> CPUFreq frequency * * Cooling states are translated to frequencies throughout this driver and this * is the relation between them. * * Highest cooling state corresponds to lowest possible frequency. * * i.e. * level 0 --> 1st Max Freq * level 1 --> 2nd Max Freq * ... */ /** * struct freq_table - frequency table along with power entries * @frequency: frequency in KHz * @power: power in mW * * This structure is built when the cooling device registers and helps * in translating frequency to power and vice versa. */ struct freq_table { u32 frequency; u32 power; }; /** * struct time_in_idle - Idle time stats * @time: previous reading of the absolute time that this cpu was idle * @timestamp: wall time of the last invocation of get_cpu_idle_time_us() */ struct time_in_idle { u64 time; u64 timestamp; }; /** * struct cpufreq_cooling_device - data for cooling device with cpufreq * @id: unique integer value corresponding to each cpufreq_cooling_device * registered. * @last_load: load measured by the latest call to cpufreq_get_requested_power() * @cpufreq_state: integer value representing the current state of cpufreq * cooling devices. * @clipped_freq: integer value representing the absolute value of the clipped * frequency. * @max_level: maximum cooling level. One less than total number of valid * cpufreq frequencies. * @freq_table: Freq table in descending order of frequencies * @cdev: thermal_cooling_device pointer to keep track of the * registered cooling device. * @policy: cpufreq policy. * @node: list_head to link all cpufreq_cooling_device together. * @idle_time: idle time stats * @plat_get_static_power: callback to calculate the static power * * This structure is required for keeping information of each registered * cpufreq_cooling_device. */ struct cpufreq_cooling_device { int id; u32 last_load; unsigned int cpufreq_state; unsigned int clipped_freq; unsigned int max_level; struct freq_table *freq_table; /* In descending order */ struct thermal_cooling_device *cdev; struct cpufreq_policy *policy; struct list_head node; struct time_in_idle *idle_time; get_static_t plat_get_static_power; }; static DEFINE_IDA(cpufreq_ida); static DEFINE_MUTEX(cooling_list_lock); static LIST_HEAD(cpufreq_cdev_list); /* Below code defines functions to be used for cpufreq as cooling device */ /** * get_level: Find the level for a particular frequency * @cpufreq_cdev: cpufreq_cdev for which the property is required * @freq: Frequency * * Return: level corresponding to the frequency. */ static unsigned long get_level(struct cpufreq_cooling_device *cpufreq_cdev, unsigned int freq) { struct freq_table *freq_table = cpufreq_cdev->freq_table; unsigned long level; for (level = 1; level <= cpufreq_cdev->max_level; level++) if (freq > freq_table[level].frequency) break; return level - 1; } /** * cpufreq_thermal_notifier - notifier callback for cpufreq policy change. * @nb: struct notifier_block * with callback info. * @event: value showing cpufreq event for which this function invoked. * @data: callback-specific data * * Callback to hijack the notification on cpufreq policy transition. * Every time there is a change in policy, we will intercept and * update the cpufreq policy with thermal constraints. * * Return: 0 (success) */ static int cpufreq_thermal_notifier(struct notifier_block *nb, unsigned long event, void *data) { struct cpufreq_policy *policy = data; unsigned long clipped_freq; struct cpufreq_cooling_device *cpufreq_cdev; if (event != CPUFREQ_ADJUST) return NOTIFY_DONE; mutex_lock(&cooling_list_lock); list_for_each_entry(cpufreq_cdev, &cpufreq_cdev_list, node) { /* * A new copy of the policy is sent to the notifier and can't * compare that directly. */ if (policy->cpu != cpufreq_cdev->policy->cpu) continue; /* * policy->max is the maximum allowed frequency defined by user * and clipped_freq is the maximum that thermal constraints * allow. * * If clipped_freq is lower than policy->max, then we need to * readjust policy->max. * * But, if clipped_freq is greater than policy->max, we don't * need to do anything. */ clipped_freq = cpufreq_cdev->clipped_freq; if (policy->max > clipped_freq) cpufreq_verify_within_limits(policy, 0, clipped_freq); break; } mutex_unlock(&cooling_list_lock); return NOTIFY_OK; } /** * update_freq_table() - Update the freq table with power numbers * @cpufreq_cdev: the cpufreq cooling device in which to update the table * @capacitance: dynamic power coefficient for these cpus * * Update the freq table with power numbers. This table will be used in * cpu_power_to_freq() and cpu_freq_to_power() to convert between power and * frequency efficiently. Power is stored in mW, frequency in KHz. The * resulting table is in descending order. * * Return: 0 on success, -EINVAL if there are no OPPs for any CPUs, * or -ENOMEM if we run out of memory. */ static int update_freq_table(struct cpufreq_cooling_device *cpufreq_cdev, u32 capacitance) { struct freq_table *freq_table = cpufreq_cdev->freq_table; struct dev_pm_opp *opp; struct device *dev = NULL; int num_opps = 0, cpu = cpufreq_cdev->policy->cpu, i; dev = get_cpu_device(cpu); if (unlikely(!dev)) { dev_warn(&cpufreq_cdev->cdev->device, "No cpu device for cpu %d\n", cpu); return -ENODEV; } num_opps = dev_pm_opp_get_opp_count(dev); if (num_opps < 0) return num_opps; /* * The cpufreq table is also built from the OPP table and so the count * should match. */ if (num_opps != cpufreq_cdev->max_level + 1) { dev_warn(dev, "Number of OPPs not matching with max_levels\n"); return -EINVAL; } for (i = 0; i <= cpufreq_cdev->max_level; i++) { unsigned long freq = freq_table[i].frequency * 1000; u32 freq_mhz = freq_table[i].frequency / 1000; u64 power; u32 voltage_mv; /* * Find ceil frequency as 'freq' may be slightly lower than OPP * freq due to truncation while converting to kHz. */ opp = dev_pm_opp_find_freq_ceil(dev, &freq); if (IS_ERR(opp)) { dev_err(dev, "failed to get opp for %lu frequency\n", freq); return -EINVAL; } voltage_mv = dev_pm_opp_get_voltage(opp) / 1000; dev_pm_opp_put(opp); /* * Do the multiplication with MHz and millivolt so as * to not overflow. */ power = (u64)capacitance * freq_mhz * voltage_mv * voltage_mv; do_div(power, 1000000000); /* power is stored in mW */ freq_table[i].power = power; } return 0; } static u32 cpu_freq_to_power(struct cpufreq_cooling_device *cpufreq_cdev, u32 freq) { int i; struct freq_table *freq_table = cpufreq_cdev->freq_table; for (i = 1; i <= cpufreq_cdev->max_level; i++) if (freq > freq_table[i].frequency) break; return freq_table[i - 1].power; } static u32 cpu_power_to_freq(struct cpufreq_cooling_device *cpufreq_cdev, u32 power) { int i; struct freq_table *freq_table = cpufreq_cdev->freq_table; for (i = 1; i <= cpufreq_cdev->max_level; i++) if (power > freq_table[i].power) break; return freq_table[i - 1].frequency; } /** * get_load() - get load for a cpu since last updated * @cpufreq_cdev: &struct cpufreq_cooling_device for this cpu * @cpu: cpu number * @cpu_idx: index of the cpu in time_in_idle* * * Return: The average load of cpu @cpu in percentage since this * function was last called. */ static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, int cpu_idx) { u32 load; u64 now, now_idle, delta_time, delta_idle; struct time_in_idle *idle_time = &cpufreq_cdev->idle_time[cpu_idx]; now_idle = get_cpu_idle_time(cpu, &now, 0); delta_idle = now_idle - idle_time->time; delta_time = now - idle_time->timestamp; if (delta_time <= delta_idle) load = 0; else load = div64_u64(100 * (delta_time - delta_idle), delta_time); idle_time->time = now_idle; idle_time->timestamp = now; return load; } /** * get_static_power() - calculate the static power consumed by the cpus * @cpufreq_cdev: struct &cpufreq_cooling_device for this cpu cdev * @tz: thermal zone device in which we're operating * @freq: frequency in KHz * @power: pointer in which to store the calculated static power * * Calculate the static power consumed by the cpus described by * @cpu_actor running at frequency @freq. This function relies on a * platform specific function that should have been provided when the * actor was registered. If it wasn't, the static power is assumed to * be negligible. The calculated static power is stored in @power. * * Return: 0 on success, -E* on failure. */ static int get_static_power(struct cpufreq_cooling_device *cpufreq_cdev, struct thermal_zone_device *tz, unsigned long freq, u32 *power) { struct dev_pm_opp *opp; unsigned long voltage; struct cpufreq_policy *policy = cpufreq_cdev->policy; struct cpumask *cpumask = policy->related_cpus; unsigned long freq_hz = freq * 1000; struct device *dev; if (!cpufreq_cdev->plat_get_static_power) { *power = 0; return 0; } dev = get_cpu_device(policy->cpu); WARN_ON(!dev); opp = dev_pm_opp_find_freq_exact(dev, freq_hz, true); if (IS_ERR(opp)) { dev_warn_ratelimited(dev, "Failed to find OPP for frequency %lu: %ld\n", freq_hz, PTR_ERR(opp)); return -EINVAL; } voltage = dev_pm_opp_get_voltage(opp); dev_pm_opp_put(opp); if (voltage == 0) { dev_err_ratelimited(dev, "Failed to get voltage for frequency %lu\n", freq_hz); return -EINVAL; } return cpufreq_cdev->plat_get_static_power(cpumask, tz->passive_delay, voltage, power); } /** * get_dynamic_power() - calculate the dynamic power * @cpufreq_cdev: &cpufreq_cooling_device for this cdev * @freq: current frequency * * Return: the dynamic power consumed by the cpus described by * @cpufreq_cdev. */ static u32 get_dynamic_power(struct cpufreq_cooling_device *cpufreq_cdev, unsigned long freq) { u32 raw_cpu_power; raw_cpu_power = cpu_freq_to_power(cpufreq_cdev, freq); return (raw_cpu_power * cpufreq_cdev->last_load) / 100; } /* cpufreq cooling device callback functions are defined below */ /** * cpufreq_get_max_state - callback function to get the max cooling state. * @cdev: thermal cooling device pointer. * @state: fill this variable with the max cooling state. * * Callback for the thermal cooling device to return the cpufreq * max cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; *state = cpufreq_cdev->max_level; return 0; } /** * cpufreq_get_cur_state - callback function to get the current cooling state. * @cdev: thermal cooling device pointer. * @state: fill this variable with the current cooling state. * * Callback for the thermal cooling device to return the cpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; *state = cpufreq_cdev->cpufreq_state; return 0; } /** * cpufreq_set_cur_state - callback function to set the current cooling state. * @cdev: thermal cooling device pointer. * @state: set this variable to the current cooling state. * * Callback for the thermal cooling device to change the cpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) { struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; unsigned int clip_freq; /* Request state should be less than max_level */ if (WARN_ON(state > cpufreq_cdev->max_level)) return -EINVAL; /* Check if the old cooling action is same as new cooling action */ if (cpufreq_cdev->cpufreq_state == state) return 0; clip_freq = cpufreq_cdev->freq_table[state].frequency; cpufreq_cdev->cpufreq_state = state; cpufreq_cdev->clipped_freq = clip_freq; cpufreq_update_policy(cpufreq_cdev->policy->cpu); return 0; } /** * cpufreq_get_requested_power() - get the current power * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @power: pointer in which to store the resulting power * * Calculate the current power consumption of the cpus in milliwatts * and store it in @power. This function should actually calculate * the requested power, but it's hard to get the frequency that * cpufreq would have assigned if there were no thermal limits. * Instead, we calculate the current power on the assumption that the * immediate future will look like the immediate past. * * We use the current frequency and the average load since this * function was last called. In reality, there could have been * multiple opps since this function was last called and that affects * the load calculation. While it's not perfectly accurate, this * simplification is good enough and works. REVISIT this, as more * complex code may be needed if experiments show that it's not * accurate enough. * * Return: 0 on success, -E* if getting the static power failed. */ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, u32 *power) { unsigned long freq; int i = 0, cpu, ret; u32 static_power, dynamic_power, total_load = 0; struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; struct cpufreq_policy *policy = cpufreq_cdev->policy; u32 *load_cpu = NULL; freq = cpufreq_quick_get(policy->cpu); if (trace_thermal_power_cpu_get_power_enabled()) { u32 ncpus = cpumask_weight(policy->related_cpus); load_cpu = kcalloc(ncpus, sizeof(*load_cpu), GFP_KERNEL); } for_each_cpu(cpu, policy->related_cpus) { u32 load; if (cpu_online(cpu)) load = get_load(cpufreq_cdev, cpu, i); else load = 0; total_load += load; if (trace_thermal_power_cpu_limit_enabled() && load_cpu) load_cpu[i] = load; i++; } cpufreq_cdev->last_load = total_load; dynamic_power = get_dynamic_power(cpufreq_cdev, freq); ret = get_static_power(cpufreq_cdev, tz, freq, &static_power); if (ret) { kfree(load_cpu); return ret; } if (load_cpu) { trace_thermal_power_cpu_get_power(policy->related_cpus, freq, load_cpu, i, dynamic_power, static_power); kfree(load_cpu); } *power = static_power + dynamic_power; return 0; } /** * cpufreq_state2power() - convert a cpu cdev state to power consumed * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @state: cooling device state to be converted * @power: pointer in which to store the resulting power * * Convert cooling device state @state into power consumption in * milliwatts assuming 100% load. Store the calculated power in * @power. * * Return: 0 on success, -EINVAL if the cooling device state could not * be converted into a frequency or other -E* if there was an error * when calculating the static power. */ static int cpufreq_state2power(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, unsigned long state, u32 *power) { unsigned int freq, num_cpus; u32 static_power, dynamic_power; int ret; struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; /* Request state should be less than max_level */ if (WARN_ON(state > cpufreq_cdev->max_level)) return -EINVAL; num_cpus = cpumask_weight(cpufreq_cdev->policy->cpus); freq = cpufreq_cdev->freq_table[state].frequency; dynamic_power = cpu_freq_to_power(cpufreq_cdev, freq) * num_cpus; ret = get_static_power(cpufreq_cdev, tz, freq, &static_power); if (ret) return ret; *power = static_power + dynamic_power; return ret; } /** * cpufreq_power2state() - convert power to a cooling device state * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @power: power in milliwatts to be converted * @state: pointer in which to store the resulting state * * Calculate a cooling device state for the cpus described by @cdev * that would allow them to consume at most @power mW and store it in * @state. Note that this calculation depends on external factors * such as the cpu load or the current static power. Calling this * function with the same power as input can yield different cooling * device states depending on those external factors. * * Return: 0 on success, -ENODEV if no cpus are online or -EINVAL if * the calculated frequency could not be converted to a valid state. * The latter should not happen unless the frequencies available to * cpufreq have changed since the initialization of the cpu cooling * device. */ static int cpufreq_power2state(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, u32 power, unsigned long *state) { unsigned int cur_freq, target_freq; int ret; s32 dyn_power; u32 last_load, normalised_power, static_power; struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; struct cpufreq_policy *policy = cpufreq_cdev->policy; cur_freq = cpufreq_quick_get(policy->cpu); ret = get_static_power(cpufreq_cdev, tz, cur_freq, &static_power); if (ret) return ret; dyn_power = power - static_power; dyn_power = dyn_power > 0 ? dyn_power : 0; last_load = cpufreq_cdev->last_load ?: 1; normalised_power = (dyn_power * 100) / last_load; target_freq = cpu_power_to_freq(cpufreq_cdev, normalised_power); *state = get_level(cpufreq_cdev, target_freq); trace_thermal_power_cpu_limit(policy->related_cpus, target_freq, *state, power); return 0; } /* Bind cpufreq callbacks to thermal cooling device ops */ static struct thermal_cooling_device_ops cpufreq_cooling_ops = { .get_max_state = cpufreq_get_max_state, .get_cur_state = cpufreq_get_cur_state, .set_cur_state = cpufreq_set_cur_state, }; static struct thermal_cooling_device_ops cpufreq_power_cooling_ops = { .get_max_state = cpufreq_get_max_state, .get_cur_state = cpufreq_get_cur_state, .set_cur_state = cpufreq_set_cur_state, .get_requested_power = cpufreq_get_requested_power, .state2power = cpufreq_state2power, .power2state = cpufreq_power2state, }; /* Notifier for cpufreq policy change */ static struct notifier_block thermal_cpufreq_notifier_block = { .notifier_call = cpufreq_thermal_notifier, }; static unsigned int find_next_max(struct cpufreq_frequency_table *table, unsigned int prev_max) { struct cpufreq_frequency_table *pos; unsigned int max = 0; cpufreq_for_each_valid_entry(pos, table) { if (pos->frequency > max && pos->frequency < prev_max) max = pos->frequency; } return max; } /** * __cpufreq_cooling_register - helper function to create cpufreq cooling device * @np: a valid struct device_node to the cooling device device tree node * @policy: cpufreq policy * Normally this should be same as cpufreq policy->related_cpus. * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. It also gives the opportunity to link the cooling device * with a device tree node, in order to bind it via the thermal DT code. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ static struct thermal_cooling_device * __cpufreq_cooling_register(struct device_node *np, struct cpufreq_policy *policy, u32 capacitance, get_static_t plat_static_func) { struct thermal_cooling_device *cdev; struct cpufreq_cooling_device *cpufreq_cdev; char dev_name[THERMAL_NAME_LENGTH]; unsigned int freq, i, num_cpus; int ret; struct thermal_cooling_device_ops *cooling_ops; bool first; if (IS_ERR_OR_NULL(policy)) { pr_err("%s: cpufreq policy isn't valid: %p", __func__, policy); return ERR_PTR(-EINVAL); } i = cpufreq_table_count_valid_entries(policy); if (!i) { pr_debug("%s: CPUFreq table not found or has no valid entries\n", __func__); return ERR_PTR(-ENODEV); } cpufreq_cdev = kzalloc(sizeof(*cpufreq_cdev), GFP_KERNEL); if (!cpufreq_cdev) return ERR_PTR(-ENOMEM); cpufreq_cdev->policy = policy; num_cpus = cpumask_weight(policy->related_cpus); cpufreq_cdev->idle_time = kcalloc(num_cpus, sizeof(*cpufreq_cdev->idle_time), GFP_KERNEL); if (!cpufreq_cdev->idle_time) { cdev = ERR_PTR(-ENOMEM); goto free_cdev; } /* max_level is an index, not a counter */ cpufreq_cdev->max_level = i - 1; cpufreq_cdev->freq_table = kmalloc_array(i, sizeof(*cpufreq_cdev->freq_table), GFP_KERNEL); if (!cpufreq_cdev->freq_table) { cdev = ERR_PTR(-ENOMEM); goto free_idle_time; } ret = ida_simple_get(&cpufreq_ida, 0, 0, GFP_KERNEL); if (ret < 0) { cdev = ERR_PTR(ret); goto free_table; } cpufreq_cdev->id = ret; snprintf(dev_name, sizeof(dev_name), "thermal-cpufreq-%d", cpufreq_cdev->id); /* Fill freq-table in descending order of frequencies */ for (i = 0, freq = -1; i <= cpufreq_cdev->max_level; i++) { freq = find_next_max(policy->freq_table, freq); cpufreq_cdev->freq_table[i].frequency = freq; /* Warn for duplicate entries */ if (!freq) pr_warn("%s: table has duplicate entries\n", __func__); else pr_debug("%s: freq:%u KHz\n", __func__, freq); } if (capacitance) { cpufreq_cdev->plat_get_static_power = plat_static_func; ret = update_freq_table(cpufreq_cdev, capacitance); if (ret) { cdev = ERR_PTR(ret); goto remove_ida; } cooling_ops = &cpufreq_power_cooling_ops; } else { cooling_ops = &cpufreq_cooling_ops; } cdev = thermal_of_cooling_device_register(np, dev_name, cpufreq_cdev, cooling_ops); if (IS_ERR(cdev)) goto remove_ida; cpufreq_cdev->clipped_freq = cpufreq_cdev->freq_table[0].frequency; cpufreq_cdev->cdev = cdev; mutex_lock(&cooling_list_lock); /* Register the notifier for first cpufreq cooling device */ first = list_empty(&cpufreq_cdev_list); list_add(&cpufreq_cdev->node, &cpufreq_cdev_list); mutex_unlock(&cooling_list_lock); if (first) cpufreq_register_notifier(&thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); return cdev; remove_ida: ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); free_table: kfree(cpufreq_cdev->freq_table); free_idle_time: kfree(cpufreq_cdev->idle_time); free_cdev: kfree(cpufreq_cdev); return cdev; } /** * cpufreq_cooling_register - function to create cpufreq cooling device. * @policy: cpufreq policy * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * cpufreq_cooling_register(struct cpufreq_policy *policy) { return __cpufreq_cooling_register(NULL, policy, 0, NULL); } EXPORT_SYMBOL_GPL(cpufreq_cooling_register); /** * of_cpufreq_cooling_register - function to create cpufreq cooling device. * @np: a valid struct device_node to the cooling device device tree node * @policy: cpufreq policy * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. Using this API, the cpufreq cooling device will be * linked to the device tree node provided. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * of_cpufreq_cooling_register(struct device_node *np, struct cpufreq_policy *policy) { if (!np) return ERR_PTR(-EINVAL); return __cpufreq_cooling_register(np, policy, 0, NULL); } EXPORT_SYMBOL_GPL(of_cpufreq_cooling_register); /** * cpufreq_power_cooling_register() - create cpufreq cooling device with power extensions * @policy: cpufreq policy * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with * the name "thermal-cpufreq-%x". This api can support multiple * instances of cpufreq cooling devices. Using this function, the * cooling device will implement the power extensions by using a * simple cpu power model. The cpus must have registered their OPPs * using the OPP library. * * An optional @plat_static_func may be provided to calculate the * static power consumed by these cpus. If the platform's static * power consumption is unknown or negligible, make it NULL. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * cpufreq_power_cooling_register(struct cpufreq_policy *policy, u32 capacitance, get_static_t plat_static_func) { return __cpufreq_cooling_register(NULL, policy, capacitance, plat_static_func); } EXPORT_SYMBOL(cpufreq_power_cooling_register); /** * of_cpufreq_power_cooling_register() - create cpufreq cooling device with power extensions * @np: a valid struct device_node to the cooling device device tree node * @policy: cpufreq policy * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with * the name "thermal-cpufreq-%x". This api can support multiple * instances of cpufreq cooling devices. Using this API, the cpufreq * cooling device will be linked to the device tree node provided. * Using this function, the cooling device will implement the power * extensions by using a simple cpu power model. The cpus must have * registered their OPPs using the OPP library. * * An optional @plat_static_func may be provided to calculate the * static power consumed by these cpus. If the platform's static * power consumption is unknown or negligible, make it NULL. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * of_cpufreq_power_cooling_register(struct device_node *np, struct cpufreq_policy *policy, u32 capacitance, get_static_t plat_static_func) { if (!np) return ERR_PTR(-EINVAL); return __cpufreq_cooling_register(np, policy, capacitance, plat_static_func); } EXPORT_SYMBOL(of_cpufreq_power_cooling_register); /** * cpufreq_cooling_unregister - function to remove cpufreq cooling device. * @cdev: thermal cooling device pointer. * * This interface function unregisters the "thermal-cpufreq-%x" cooling device. */ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) { struct cpufreq_cooling_device *cpufreq_cdev; bool last; if (!cdev) return; cpufreq_cdev = cdev->devdata; mutex_lock(&cooling_list_lock); list_del(&cpufreq_cdev->node); /* Unregister the notifier for the last cpufreq cooling device */ last = list_empty(&cpufreq_cdev_list); mutex_unlock(&cooling_list_lock); if (last) cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); thermal_cooling_device_unregister(cpufreq_cdev->cdev); ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); kfree(cpufreq_cdev->idle_time); kfree(cpufreq_cdev->freq_table); kfree(cpufreq_cdev); } EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister);