drivers/macintosh/windfarm.h

   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
  18 /* Display a 16.16 fixed point value */
  19 #define FIX32TOPRINT(f) ((f) >> 16),((((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         struct wf_control_ops   *ops;
  39         char                    *name;
  40         int                     type;
  41         struct kref             ref;
  42 };
  43
  44 #define WF_CONTROL_TYPE_GENERIC         0
  45 #define WF_CONTROL_RPM_FAN              1
  46 #define WF_CONTROL_PWM_FAN              2
  47
  48
  49 /* Note about lifetime rules: wf_register_control() will initialize
  50  * the kref and wf_unregister_control will decrement it, thus the
  51  * object creating/disposing a given control shouldn't assume it
  52  * still exists after wf_unregister_control has been called.
  53  * wf_find_control will inc the refcount for you
  54  */
  55 extern int wf_register_control(struct wf_control *ct);
  56 extern void wf_unregister_control(struct wf_control *ct);
  57 extern struct wf_control * wf_find_control(const char *name);
  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 /*
  74  * Sensor objects
  75  */
  76
  77 struct wf_sensor;
  78
  79 struct wf_sensor_ops {
  80         int                     (*get_value)(struct wf_sensor *sr, s32 *val);
  81         void                    (*release)(struct wf_sensor *sr);
  82         struct module           *owner;
  83 };
  84
  85 struct wf_sensor {
  86         struct list_head        link;
  87         struct wf_sensor_ops    *ops;
  88         char                    *name;
  89         struct kref             ref;
  90 };
  91
  92 /* Same lifetime rules as controls */
  93 extern int wf_register_sensor(struct wf_sensor *sr);
  94 extern void wf_unregister_sensor(struct wf_sensor *sr);
  95 extern struct wf_sensor * wf_find_sensor(const char *name);
  96 extern int wf_get_sensor(struct wf_sensor *sr);
  97 extern void wf_put_sensor(struct wf_sensor *sr);
  98
  99 /* For use by clients. Note that we are a bit racy here since
 100  * notifier_block doesn't have a module owner field. I may fix
 101  * it one day ...
 102  *
 103  * LOCKING NOTE !
 104  *
 105  * All "events" except WF_EVENT_TICK are called with an internal mutex
 106  * held which will deadlock if you call basically any core routine.
 107  * So don't ! Just take note of the event and do your actual operations
 108  * from the ticker.
 109  *
 110  */
 111 extern int wf_register_client(struct notifier_block *nb);
 112 extern int wf_unregister_client(struct notifier_block *nb);
 113
 114 /* Overtemp conditions. Those are refcounted */
 115 extern void wf_set_overtemp(void);
 116 extern void wf_clear_overtemp(void);
 117 extern int wf_is_overtemp(void);
 118
 119 #define WF_EVENT_NEW_CONTROL    0 /* param is wf_control * */
 120 #define WF_EVENT_NEW_SENSOR     1 /* param is wf_sensor * */
 121 #define WF_EVENT_OVERTEMP       2 /* no param */
 122 #define WF_EVENT_NORMALTEMP     3 /* overtemp condition cleared */
 123 #define WF_EVENT_TICK           4 /* 1 second tick */
 124
 125 /* Note: If that driver gets more broad use, we could replace the
 126  * simplistic overtemp bits with "environmental conditions". That
 127  * could then be used to also notify of things like fan failure,
 128  * case open, battery conditions, ...
 129  */
 130
 131 #endif /* __WINDFARM_H__ */