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  */
  57 extern int wf_register_control(struct wf_control *ct);
  58 extern void wf_unregister_control(struct wf_control *ct);
  59 extern int wf_get_control(struct wf_control *ct);
  60 extern void wf_put_control(struct wf_control *ct);
  61
  62 static inline int wf_control_set_max(struct wf_control *ct)
  63 {
  64         s32 vmax = ct->ops->get_max(ct);
  65         return ct->ops->set_value(ct, vmax);
  66 }
  67
  68 static inline int wf_control_set_min(struct wf_control *ct)
  69 {
  70         s32 vmin = ct->ops->get_min(ct);
  71         return ct->ops->set_value(ct, vmin);
  72 }
  73
  74 static inline int wf_control_set(struct wf_control *ct, s32 val)
  75 {
  76         return ct->ops->set_value(ct, val);
  77 }
  78
  79 static inline int wf_control_get(struct wf_control *ct, s32 *val)
  80 {
  81         return ct->ops->get_value(ct, val);
  82 }
  83
  84 static inline s32 wf_control_get_min(struct wf_control *ct)
  85 {
  86         return ct->ops->get_min(ct);
  87 }
  88
  89 static inline s32 wf_control_get_max(struct wf_control *ct)
  90 {
  91         return ct->ops->get_max(ct);
  92 }
  93
  94 /*
  95  * Sensor objects
  96  */
  97
  98 struct wf_sensor;
  99
 100 struct wf_sensor_ops {
 101         int                     (*get_value)(struct wf_sensor *sr, s32 *val);
 102         void                    (*release)(struct wf_sensor *sr);
 103         struct module           *owner;
 104 };
 105
 106 struct wf_sensor {
 107         struct list_head                link;
 108         const struct wf_sensor_ops      *ops;
 109         const char                      *name;
 110         struct kref                     ref;
 111         struct device_attribute         attr;
 112         void                            *priv;
 113 };
 114
 115 /* Same lifetime rules as controls */
 116 extern int wf_register_sensor(struct wf_sensor *sr);
 117 extern void wf_unregister_sensor(struct wf_sensor *sr);
 118 extern int wf_get_sensor(struct wf_sensor *sr);
 119 extern void wf_put_sensor(struct wf_sensor *sr);
 120
 121 static inline int wf_sensor_get(struct wf_sensor *sr, s32 *val)
 122 {
 123         return sr->ops->get_value(sr, val);
 124 }
 125
 126 /* For use by clients. Note that we are a bit racy here since
 127  * notifier_block doesn't have a module owner field. I may fix
 128  * it one day ...
 129  *
 130  * LOCKING NOTE !
 131  *
 132  * All "events" except WF_EVENT_TICK are called with an internal mutex
 133  * held which will deadlock if you call basically any core routine.
 134  * So don't ! Just take note of the event and do your actual operations
 135  * from the ticker.
 136  *
 137  */
 138 extern int wf_register_client(struct notifier_block *nb);
 139 extern int wf_unregister_client(struct notifier_block *nb);
 140
 141 /* Overtemp conditions. Those are refcounted */
 142 extern void wf_set_overtemp(void);
 143 extern void wf_clear_overtemp(void);
 144
 145 #define WF_EVENT_NEW_CONTROL    0 /* param is wf_control * */
 146 #define WF_EVENT_NEW_SENSOR     1 /* param is wf_sensor * */
 147 #define WF_EVENT_OVERTEMP       2 /* no param */
 148 #define WF_EVENT_NORMALTEMP     3 /* overtemp condition cleared */
 149 #define WF_EVENT_TICK           4 /* 1 second tick */
 150
 151 /* Note: If that driver gets more broad use, we could replace the
 152  * simplistic overtemp bits with "environmental conditions". That
 153  * could then be used to also notify of things like fan failure,
 154  * case open, battery conditions, ...
 155  */
 156
 157 #endif /* __WINDFARM_H__ */