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 #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
  26 struct wf_control;
  27
  28 struct 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
  37 struct 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  */
  58 extern int wf_register_control(struct wf_control *ct);
  59 extern void wf_unregister_control(struct wf_control *ct);
  60 extern struct wf_control * wf_find_control(const char *name);
  61 extern int wf_get_control(struct wf_control *ct);
  62 extern void wf_put_control(struct wf_control *ct);
  63
  64 static 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
  70 static 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
  76 static inline int wf_control_set(struct wf_control *ct, s32 val)
  77 {
  78         return ct->ops->set_value(ct, val);
  79 }
  80
  81 static inline int wf_control_get(struct wf_control *ct, s32 *val)
  82 {
  83         return ct->ops->get_value(ct, val);
  84 }
  85
  86 static inline s32 wf_control_get_min(struct wf_control *ct)
  87 {
  88         return ct->ops->get_min(ct);
  89 }
  90
  91 static 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
 100 struct wf_sensor;
 101
 102 struct 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
 108 struct 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 */
 118 extern int wf_register_sensor(struct wf_sensor *sr);
 119 extern void wf_unregister_sensor(struct wf_sensor *sr);
 120 extern struct wf_sensor * wf_find_sensor(const char *name);
 121 extern int wf_get_sensor(struct wf_sensor *sr);
 122 extern void wf_put_sensor(struct wf_sensor *sr);
 123
 124 static 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  */
 141 extern int wf_register_client(struct notifier_block *nb);
 142 extern int wf_unregister_client(struct notifier_block *nb);
 143
 144 /* Overtemp conditions. Those are refcounted */
 145 extern void wf_set_overtemp(void);
 146 extern void wf_clear_overtemp(void);
 147 extern 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__ */