LXR linux/include/linux/devfreq

   1/*
   2 * devfreq_cooling: Thermal cooling device implementation for devices using
   3 *                  devfreq
   4 *
   5 * Copyright (C) 2014-2015 ARM Limited
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  12 * kind, whether express or implied; without even the implied warranty
  13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 */
  16
  17#ifndef __DEVFREQ_COOLING_H__
  18#define __DEVFREQ_COOLING_H__
  19
  20#include <linux/devfreq.h>
  21#include <linux/thermal.h>
  22
  23
  24/**
  25 * struct devfreq_cooling_power - Devfreq cooling power ops
  26 * @get_static_power:   Take voltage, in mV, and return the static power
  27 *                      in mW.  If NULL, the static power is assumed
  28 *                      to be 0.
  29 * @get_dynamic_power:  Take voltage, in mV, and frequency, in HZ, and
  30 *                      return the dynamic power draw in mW.  If NULL,
  31 *                      a simple power model is used.
  32 * @dyn_power_coeff:    Coefficient for the simple dynamic power model in
  33 *                      mW/(MHz mV mV).
  34 *                      If get_dynamic_power() is NULL, then the
  35 *                      dynamic power is calculated as
  36 *                      @dyn_power_coeff * frequency * voltage^2
  37 * @get_real_power:     When this is set, the framework uses it to ask the
  38 *                      device driver for the actual power.
  39 *                      Some devices have more sophisticated methods
  40 *                      (like power counters) to approximate the actual power
  41 *                      that they use.
  42 *                      This function provides more accurate data to the
  43 *                      thermal governor. When the driver does not provide
  44 *                      such function, framework just uses pre-calculated
  45 *                      table and scale the power by 'utilization'
  46 *                      (based on 'busy_time' and 'total_time' taken from
  47 *                      devfreq 'last_status').
  48 *                      The value returned by this function must be lower
  49 *                      or equal than the maximum power value
  50 *                      for the current state
  51 *                      (which can be found in power_table[state]).
  52 *                      When this interface is used, the power_table holds
  53 *                      max total (static + dynamic) power value for each OPP.
  54 */
  55struct devfreq_cooling_power {
  56        unsigned long (*get_static_power)(struct devfreq *devfreq,
  57                                          unsigned long voltage);
  58        unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
  59                                           unsigned long freq,
  60                                           unsigned long voltage);
  61        int (*get_real_power)(struct devfreq *df, u32 *power,
  62                              unsigned long freq, unsigned long voltage);
  63        unsigned long dyn_power_coeff;
  64};
  65
  66#ifdef CONFIG_DEVFREQ_THERMAL
  67
  68struct thermal_cooling_device *
  69of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
  70                                  struct devfreq_cooling_power *dfc_power);
  71struct thermal_cooling_device *
  72of_devfreq_cooling_register(struct device_node *np, struct devfreq *df);
  73struct thermal_cooling_device *devfreq_cooling_register(struct devfreq *df);
  74void devfreq_cooling_unregister(struct thermal_cooling_device *dfc);
  75
  76#else /* !CONFIG_DEVFREQ_THERMAL */
  77
  78struct thermal_cooling_device *
  79of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
  80                                  struct devfreq_cooling_power *dfc_power)
  81{
  82        return ERR_PTR(-EINVAL);
  83}
  84
  85static inline struct thermal_cooling_device *
  86of_devfreq_cooling_register(struct device_node *np, struct devfreq *df)
  87{
  88        return ERR_PTR(-EINVAL);
  89}
  90
  91static inline struct thermal_cooling_device *
  92devfreq_cooling_register(struct devfreq *df)
  93{
  94        return ERR_PTR(-EINVAL);
  95}
  96
  97static inline void
  98devfreq_cooling_unregister(struct thermal_cooling_device *dfc)
  99{
 100}
 101
 102#endif /* CONFIG_DEVFREQ_THERMAL */
 103#endif /* __DEVFREQ_COOLING_H__ */
 104