1/*
2 * Windfarm PowerMac thermal control.
3 *
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 *                    <benh@kernel.crashing.org>
6 *
7 * Released under the term of the GNU GPL v2.
8 */
9
10#ifndef __WINDFARM_H__
11#define __WINDFARM_H__
12
13#include <linux/kref.h>
14#include <linux/list.h>
15#include <linux/module.h>
16#include <linux/notifier.h>
17#include <linux/device.h>
18
19/* Display a 16.16 fixed point value */
20#define FIX32TOPRINT(f)	(((s32)(f)) >> 16),(((((s32)(f)) & 0xffff) * 1000) >> 16)
21
22/*
23 * Control objects
24 */
25
26struct wf_control;
27
28struct wf_control_ops {
29	int			(*set_value)(struct wf_control *ct, s32 val);
30	int			(*get_value)(struct wf_control *ct, s32 *val);
31	s32			(*get_min)(struct wf_control *ct);
32	s32			(*get_max)(struct wf_control *ct);
33	void			(*release)(struct wf_control *ct);
34	struct module		*owner;
35};
36
37struct wf_control {
38	struct list_head		link;
39	const struct wf_control_ops	*ops;
40	const char			*name;
41	int				type;
42	struct kref			ref;
43	struct device_attribute		attr;
44	void				*priv;
45};
46
47#define WF_CONTROL_TYPE_GENERIC		0
48#define WF_CONTROL_RPM_FAN		1
49#define WF_CONTROL_PWM_FAN		2
50
51
52/* Note about lifetime rules: wf_register_control() will initialize
53 * the kref and wf_unregister_control will decrement it, thus the
54 * object creating/disposing a given control shouldn't assume it
55 * still exists after wf_unregister_control has been called.
56 * wf_find_control will inc the refcount for you
57 */
58extern int wf_register_control(struct wf_control *ct);
59extern void wf_unregister_control(struct wf_control *ct);
60extern struct wf_control * wf_find_control(const char *name);
61extern int wf_get_control(struct wf_control *ct);
62extern void wf_put_control(struct wf_control *ct);
63
64static inline int wf_control_set_max(struct wf_control *ct)
65{
66	s32 vmax = ct->ops->get_max(ct);
67	return ct->ops->set_value(ct, vmax);
68}
69
70static inline int wf_control_set_min(struct wf_control *ct)
71{
72	s32 vmin = ct->ops->get_min(ct);
73	return ct->ops->set_value(ct, vmin);
74}
75
76static inline int wf_control_set(struct wf_control *ct, s32 val)
77{
78	return ct->ops->set_value(ct, val);
79}
80
81static inline int wf_control_get(struct wf_control *ct, s32 *val)
82{
83	return ct->ops->get_value(ct, val);
84}
85
86static inline s32 wf_control_get_min(struct wf_control *ct)
87{
88	return ct->ops->get_min(ct);
89}
90
91static inline s32 wf_control_get_max(struct wf_control *ct)
92{
93	return ct->ops->get_max(ct);
94}
95
96/*
97 * Sensor objects
98 */
99
100struct wf_sensor;
101
102struct wf_sensor_ops {
103	int			(*get_value)(struct wf_sensor *sr, s32 *val);
104	void			(*release)(struct wf_sensor *sr);
105	struct module		*owner;
106};
107
108struct wf_sensor {
109	struct list_head		link;
110	const struct wf_sensor_ops	*ops;
111	const char			*name;
112	struct kref			ref;
113	struct device_attribute		attr;
114	void				*priv;
115};
116
117/* Same lifetime rules as controls */
118extern int wf_register_sensor(struct wf_sensor *sr);
119extern void wf_unregister_sensor(struct wf_sensor *sr);
120extern struct wf_sensor * wf_find_sensor(const char *name);
121extern int wf_get_sensor(struct wf_sensor *sr);
122extern void wf_put_sensor(struct wf_sensor *sr);
123
124static inline int wf_sensor_get(struct wf_sensor *sr, s32 *val)
125{
126	return sr->ops->get_value(sr, val);
127}
128
129/* For use by clients. Note that we are a bit racy here since
130 * notifier_block doesn't have a module owner field. I may fix
131 * it one day ...
132 *
133 * LOCKING NOTE !
134 *
135 * All "events" except WF_EVENT_TICK are called with an internal mutex
136 * held which will deadlock if you call basically any core routine.
137 * So don't ! Just take note of the event and do your actual operations
138 * from the ticker.
139 *
140 */
141extern int wf_register_client(struct notifier_block *nb);
142extern int wf_unregister_client(struct notifier_block *nb);
143
144/* Overtemp conditions. Those are refcounted */
145extern void wf_set_overtemp(void);
146extern void wf_clear_overtemp(void);
147extern int wf_is_overtemp(void);
148
149#define WF_EVENT_NEW_CONTROL	0 /* param is wf_control * */
150#define WF_EVENT_NEW_SENSOR	1 /* param is wf_sensor * */
151#define WF_EVENT_OVERTEMP	2 /* no param */
152#define WF_EVENT_NORMALTEMP	3 /* overtemp condition cleared */
153#define WF_EVENT_TICK		4 /* 1 second tick */
154
155/* Note: If that driver gets more broad use, we could replace the
156 * simplistic overtemp bits with "environmental conditions". That
157 * could then be used to also notify of things like fan failure,
158 * case open, battery conditions, ...
159 */
160
161#endif /* __WINDFARM_H__ */
162