1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* Fan control module for Chrome EC */
#ifndef __CROS_EC_FAN_H
#define __CROS_EC_FAN_H
/* Characteristic of each physical fan */
struct fan_t {
unsigned int flags;
int rpm_min;
int rpm_max;
/* Hardware channel number (the meaning is chip-specific) */
int ch;
/* Active-high power_good input GPIO, or -1 if none */
int pgood_gpio;
/* Active-high power_enable output GPIO, or -1 if none */
int enable_gpio;
};
/* Values for the flags field */
#define FAN_USE_RPM_MODE (1 << 0)
/* The list of fans is instantiated in board.c. */
extern const struct fan_t fans[];
/**
* Set the amount of active cooling needed. The thermal control task will call
* this frequently, and the fan control logic will attempt to provide it.
*
* @param fan Fan number (index into fans[])
* @param pct Percentage of cooling effort needed (0 - 100)
*/
void fan_set_percent_needed(int fan, int pct);
/**
* This function translates the percentage of cooling needed into a target RPM.
* The default implementation should be sufficient for most needs, but
* individual boards may provide a custom version if needed (see config.h).
*
* @param fan Fan number (index into fans[])
* @param pct Percentage of cooling effort needed (always in [0,100])
* Return Target RPM for fan
*/
int fan_percent_to_rpm(int fan, int pct);
/**
* These functions require chip-specific implementations.
*/
/* Enable/Disable the fan controller */
void fan_set_enabled(int ch, int enabled);
int fan_get_enabled(int ch);
/* Fixed pwm duty cycle (0-100%) */
void fan_set_duty(int ch, int percent);
int fan_get_duty(int ch);
/* Enable/Disable automatic RPM control using tach feedback */
void fan_set_rpm_mode(int ch, int rpm_mode);
int fan_get_rpm_mode(int ch);
/* Set the target for the automatic RPM control */
void fan_set_rpm_target(int ch, int rpm);
int fan_get_rpm_actual(int ch);
int fan_get_rpm_target(int ch);
/* Is the fan stalled when it shouldn't be? */
int fan_is_stalled(int ch);
/* How is the automatic RPM control doing? */
enum fan_status {
FAN_STATUS_STOPPED = 0,
FAN_STATUS_CHANGING = 1,
FAN_STATUS_LOCKED = 2,
FAN_STATUS_FRUSTRATED = 3
};
enum fan_status fan_get_status(int ch);
/* Flag to enable automatic RPM control using tach input */
#define FAN_USE_RPM_MODE (1 << 0)
/* Initialize the HW according to the desired flags */
void fan_channel_setup(int ch, unsigned int flags);
#endif /* __CROS_EC_FAN_H */
|