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)	((f) >> 16),((((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	struct wf_control_ops	*ops;
40	char			*name;
41	int			type;
42	struct kref		ref;
43	struct device_attribute	attr;
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 * wf_find_control will inc the refcount for you
56 */
57extern int wf_register_control(struct wf_control *ct);
58extern void wf_unregister_control(struct wf_control *ct);
59extern struct wf_control * wf_find_control(const char *name);
60extern int wf_get_control(struct wf_control *ct);
61extern void wf_put_control(struct wf_control *ct);
62
63static inline int wf_control_set_max(struct wf_control *ct)
64{
65	s32 vmax = ct->ops->get_max(ct);
66	return ct->ops->set_value(ct, vmax);
67}
68
69static inline int wf_control_set_min(struct wf_control *ct)
70{
71	s32 vmin = ct->ops->get_min(ct);
72	return ct->ops->set_value(ct, vmin);
73}
74
75/*
76 * Sensor objects
77 */
78
79struct wf_sensor;
80
81struct wf_sensor_ops {
82	int			(*get_value)(struct wf_sensor *sr, s32 *val);
83	void			(*release)(struct wf_sensor *sr);
84	struct module		*owner;
85};
86
87struct wf_sensor {
88	struct list_head	link;
89	struct wf_sensor_ops	*ops;
90	char			*name;
91	struct kref		ref;
92	struct device_attribute	attr;
93};
94
95/* Same lifetime rules as controls */
96extern int wf_register_sensor(struct wf_sensor *sr);
97extern void wf_unregister_sensor(struct wf_sensor *sr);
98extern struct wf_sensor * wf_find_sensor(const char *name);
99extern int wf_get_sensor(struct wf_sensor *sr);
100extern void wf_put_sensor(struct wf_sensor *sr);
101
102/* For use by clients. Note that we are a bit racy here since
103 * notifier_block doesn't have a module owner field. I may fix
104 * it one day ...
105 *
106 * LOCKING NOTE !
107 *
108 * All "events" except WF_EVENT_TICK are called with an internal mutex
109 * held which will deadlock if you call basically any core routine.
110 * So don't ! Just take note of the event and do your actual operations
111 * from the ticker.
112 *
113 */
114extern int wf_register_client(struct notifier_block *nb);
115extern int wf_unregister_client(struct notifier_block *nb);
116
117/* Overtemp conditions. Those are refcounted */
118extern void wf_set_overtemp(void);
119extern void wf_clear_overtemp(void);
120extern int wf_is_overtemp(void);
121
122#define WF_EVENT_NEW_CONTROL	0 /* param is wf_control * */
123#define WF_EVENT_NEW_SENSOR	1 /* param is wf_sensor * */
124#define WF_EVENT_OVERTEMP	2 /* no param */
125#define WF_EVENT_NORMALTEMP	3 /* overtemp condition cleared */
126#define WF_EVENT_TICK		4 /* 1 second tick */
127
128/* Note: If that driver gets more broad use, we could replace the
129 * simplistic overtemp bits with "environmental conditions". That
130 * could then be used to also notify of things like fan failure,
131 * case open, battery conditions, ...
132 */
133
134#endif /* __WINDFARM_H__ */
135