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_static_power: Take voltage, in mV, and return the static power
20 * in mW. If NULL, the static power is assumed
21 * to be 0.
22 * @get_dynamic_power: Take voltage, in mV, and frequency, in HZ, and
23 * return the dynamic power draw in mW. If NULL,
24 * a simple power model is used.
25 * @dyn_power_coeff: Coefficient for the simple dynamic power model in
26 * mW/(MHz mV mV).
27 * If get_dynamic_power() is NULL, then the
28 * dynamic power is calculated as
29 * @dyn_power_coeff * frequency * voltage^2
30 * @get_real_power: When this is set, the framework uses it to ask the
31 * device driver for the actual power.
32 * Some devices have more sophisticated methods
33 * (like power counters) to approximate the actual power
34 * that they use.
35 * This function provides more accurate data to the
36 * thermal governor. When the driver does not provide
37 * such function, framework just uses pre-calculated
38 * table and scale the power by 'utilization'
39 * (based on 'busy_time' and 'total_time' taken from
40 * devfreq 'last_status').
41 * The value returned by this function must be lower
42 * or equal than the maximum power value
43 * for the current state
44 * (which can be found in power_table[state]).
45 * When this interface is used, the power_table holds
46 * max total (static + dynamic) power value for each OPP.
47 */
48 struct devfreq_cooling_power {
49 unsigned long (*get_static_power)(struct devfreq *devfreq,
50 unsigned long voltage);
51 unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
52 unsigned long freq,
53 unsigned long voltage);
54 int (*get_real_power)(struct devfreq *df, u32 *power,
55 unsigned long freq, unsigned long voltage);
56 unsigned long dyn_power_coeff;
57 };
58
59 #ifdef CONFIG_DEVFREQ_THERMAL
60
61 struct thermal_cooling_device *
62 of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
63 struct devfreq_cooling_power *dfc_power);
64 struct thermal_cooling_device *
65 of_devfreq_cooling_register(struct device_node *np, struct devfreq *df);
66 struct thermal_cooling_device *devfreq_cooling_register(struct devfreq *df);
67 void devfreq_cooling_unregister(struct thermal_cooling_device *dfc);
68
69 #else /* !CONFIG_DEVFREQ_THERMAL */
70
71 static inline struct thermal_cooling_device *
of_devfreq_cooling_register_power(struct device_node * np,struct devfreq * df,struct devfreq_cooling_power * dfc_power)72 of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
73 struct devfreq_cooling_power *dfc_power)
74 {
75 return ERR_PTR(-EINVAL);
76 }
77
78 static inline struct thermal_cooling_device *
of_devfreq_cooling_register(struct device_node * np,struct devfreq * df)79 of_devfreq_cooling_register(struct device_node *np, struct devfreq *df)
80 {
81 return ERR_PTR(-EINVAL);
82 }
83
84 static inline struct thermal_cooling_device *
devfreq_cooling_register(struct devfreq * df)85 devfreq_cooling_register(struct devfreq *df)
86 {
87 return ERR_PTR(-EINVAL);
88 }
89
90 static inline void
devfreq_cooling_unregister(struct thermal_cooling_device * dfc)91 devfreq_cooling_unregister(struct thermal_cooling_device *dfc)
92 {
93 }
94
95 #endif /* CONFIG_DEVFREQ_THERMAL */
96 #endif /* __DEVFREQ_COOLING_H__ */
97