1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Windfarm PowerMac thermal control. |
4 | * |
5 | * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp. |
6 | * <benh@kernel.crashing.org> |
7 | */ |
8 | |
9 | #ifndef __WINDFARM_H__ |
10 | #define __WINDFARM_H__ |
11 | |
12 | #include <linux/kref.h> |
13 | #include <linux/list.h> |
14 | #include <linux/module.h> |
15 | #include <linux/notifier.h> |
16 | #include <linux/device.h> |
17 | |
18 | /* Display a 16.16 fixed point value */ |
19 | #define FIX32TOPRINT(f) (((s32)(f)) >> 16),(((((s32)(f)) & 0xffff) * 1000) >> 16) |
20 | |
21 | /* |
22 | * Control objects |
23 | */ |
24 | |
25 | struct wf_control; |
26 | |
27 | struct wf_control_ops { |
28 | int (*set_value)(struct wf_control *ct, s32 val); |
29 | int (*get_value)(struct wf_control *ct, s32 *val); |
30 | s32 (*get_min)(struct wf_control *ct); |
31 | s32 (*get_max)(struct wf_control *ct); |
32 | void (*release)(struct wf_control *ct); |
33 | struct module *owner; |
34 | }; |
35 | |
36 | struct wf_control { |
37 | struct list_head link; |
38 | const struct wf_control_ops *ops; |
39 | const char *name; |
40 | int type; |
41 | struct kref ref; |
42 | struct device_attribute attr; |
43 | void *priv; |
44 | }; |
45 | |
46 | #define WF_CONTROL_TYPE_GENERIC 0 |
47 | #define WF_CONTROL_RPM_FAN 1 |
48 | #define WF_CONTROL_PWM_FAN 2 |
49 | |
50 | |
51 | /* Note about lifetime rules: wf_register_control() will initialize |
52 | * the kref and wf_unregister_control will decrement it, thus the |
53 | * object creating/disposing a given control shouldn't assume it |
54 | * still exists after wf_unregister_control has been called. |
55 | */ |
56 | extern int wf_register_control(struct wf_control *ct); |
57 | extern void wf_unregister_control(struct wf_control *ct); |
58 | extern int wf_get_control(struct wf_control *ct); |
59 | extern void wf_put_control(struct wf_control *ct); |
60 | |
61 | static inline int wf_control_set_max(struct wf_control *ct) |
62 | { |
63 | s32 vmax = ct->ops->get_max(ct); |
64 | return ct->ops->set_value(ct, vmax); |
65 | } |
66 | |
67 | static inline int wf_control_set_min(struct wf_control *ct) |
68 | { |
69 | s32 vmin = ct->ops->get_min(ct); |
70 | return ct->ops->set_value(ct, vmin); |
71 | } |
72 | |
73 | static inline int wf_control_set(struct wf_control *ct, s32 val) |
74 | { |
75 | return ct->ops->set_value(ct, val); |
76 | } |
77 | |
78 | static inline int wf_control_get(struct wf_control *ct, s32 *val) |
79 | { |
80 | return ct->ops->get_value(ct, val); |
81 | } |
82 | |
83 | static inline s32 wf_control_get_min(struct wf_control *ct) |
84 | { |
85 | return ct->ops->get_min(ct); |
86 | } |
87 | |
88 | static inline s32 wf_control_get_max(struct wf_control *ct) |
89 | { |
90 | return ct->ops->get_max(ct); |
91 | } |
92 | |
93 | /* |
94 | * Sensor objects |
95 | */ |
96 | |
97 | struct wf_sensor; |
98 | |
99 | struct wf_sensor_ops { |
100 | int (*get_value)(struct wf_sensor *sr, s32 *val); |
101 | void (*release)(struct wf_sensor *sr); |
102 | struct module *owner; |
103 | }; |
104 | |
105 | struct wf_sensor { |
106 | struct list_head link; |
107 | const struct wf_sensor_ops *ops; |
108 | const char *name; |
109 | struct kref ref; |
110 | struct device_attribute attr; |
111 | void *priv; |
112 | }; |
113 | |
114 | /* Same lifetime rules as controls */ |
115 | extern int wf_register_sensor(struct wf_sensor *sr); |
116 | extern void wf_unregister_sensor(struct wf_sensor *sr); |
117 | extern int wf_get_sensor(struct wf_sensor *sr); |
118 | extern void wf_put_sensor(struct wf_sensor *sr); |
119 | |
120 | static inline int wf_sensor_get(struct wf_sensor *sr, s32 *val) |
121 | { |
122 | return sr->ops->get_value(sr, val); |
123 | } |
124 | |
125 | /* For use by clients. Note that we are a bit racy here since |
126 | * notifier_block doesn't have a module owner field. I may fix |
127 | * it one day ... |
128 | * |
129 | * LOCKING NOTE ! |
130 | * |
131 | * All "events" except WF_EVENT_TICK are called with an internal mutex |
132 | * held which will deadlock if you call basically any core routine. |
133 | * So don't ! Just take note of the event and do your actual operations |
134 | * from the ticker. |
135 | * |
136 | */ |
137 | extern int wf_register_client(struct notifier_block *nb); |
138 | extern int wf_unregister_client(struct notifier_block *nb); |
139 | |
140 | /* Overtemp conditions. Those are refcounted */ |
141 | extern void wf_set_overtemp(void); |
142 | extern void wf_clear_overtemp(void); |
143 | |
144 | #define WF_EVENT_NEW_CONTROL 0 /* param is wf_control * */ |
145 | #define WF_EVENT_NEW_SENSOR 1 /* param is wf_sensor * */ |
146 | #define WF_EVENT_OVERTEMP 2 /* no param */ |
147 | #define WF_EVENT_NORMALTEMP 3 /* overtemp condition cleared */ |
148 | #define WF_EVENT_TICK 4 /* 1 second tick */ |
149 | |
150 | /* Note: If that driver gets more broad use, we could replace the |
151 | * simplistic overtemp bits with "environmental conditions". That |
152 | * could then be used to also notify of things like fan failure, |
153 | * case open, battery conditions, ... |
154 | */ |
155 | |
156 | #endif /* __WINDFARM_H__ */ |
157 | |