include/linux/devfreq_cooling.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * devfreq_cooling: Thermal cooling device implementation for devices using
   4  *                  devfreq
   5  *
   6  * Copyright (C) 2014-2015 ARM Limited
   7  *
   8  */
   9
  10 #ifndef __DEVFREQ_COOLING_H__
  11 #define __DEVFREQ_COOLING_H__
  12
  13 #include <linux/devfreq.h>
  14 #include <linux/thermal.h>
  15
  16
  17 /**
  18  * struct devfreq_cooling_power - Devfreq cooling power ops
  19  * @get_real_power:     When this is set, the framework uses it to ask the
  20  *                      device driver for the actual power.
  21  *                      Some devices have more sophisticated methods
  22  *                      (like power counters) to approximate the actual power
  23  *                      that they use.
  24  *                      This function provides more accurate data to the
  25  *                      thermal governor. When the driver does not provide
  26  *                      such function, framework just uses pre-calculated
  27  *                      table and scale the power by 'utilization'
  28  *                      (based on 'busy_time' and 'total_time' taken from
  29  *                      devfreq 'last_status').
  30  *                      The value returned by this function must be lower
  31  *                      or equal than the maximum power value
  32  *                      for the current state
  33  *                      (which can be found in power_table[state]).
  34  *                      When this interface is used, the power_table holds
  35  *                      max total (static + dynamic) power value for each OPP.
  36  */
  37 struct devfreq_cooling_power {
  38         int (*get_real_power)(struct devfreq *df, u32 *power,
  39                               unsigned long freq, unsigned long voltage);
  40 };
  41
  42 #ifdef CONFIG_DEVFREQ_THERMAL
  43
  44 struct thermal_cooling_device *
  45 of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
  46                                   struct devfreq_cooling_power *dfc_power);
  47 struct thermal_cooling_device *
  48 of_devfreq_cooling_register(struct device_node *np, struct devfreq *df);
  49 struct thermal_cooling_device *devfreq_cooling_register(struct devfreq *df);
  50 void devfreq_cooling_unregister(struct thermal_cooling_device *dfc);
  51 struct thermal_cooling_device *
  52 devfreq_cooling_em_register(struct devfreq *df,
  53                             struct devfreq_cooling_power *dfc_power);
  54
  55 #else /* !CONFIG_DEVFREQ_THERMAL */
  56
  57 static inline struct thermal_cooling_device *
  58 of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
  59                                   struct devfreq_cooling_power *dfc_power)
  60 {
  61         return ERR_PTR(-EINVAL);
  62 }
  63
  64 static inline struct thermal_cooling_device *
  65 of_devfreq_cooling_register(struct device_node *np, struct devfreq *df)
  66 {
  67         return ERR_PTR(-EINVAL);
  68 }
  69
  70 static inline struct thermal_cooling_device *
  71 devfreq_cooling_register(struct devfreq *df)
  72 {
  73         return ERR_PTR(-EINVAL);
  74 }
  75
  76 static inline struct thermal_cooling_device *
  77 devfreq_cooling_em_register(struct devfreq *df,
  78                             struct devfreq_cooling_power *dfc_power)
  79 {
  80         return ERR_PTR(-EINVAL);
  81 }
  82
  83 static inline void
  84 devfreq_cooling_unregister(struct thermal_cooling_device *dfc)
  85 {
  86 }
  87
  88 #endif /* CONFIG_DEVFREQ_THERMAL */
  89 #endif /* __DEVFREQ_COOLING_H__ */