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) ((f) >> 16),((((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         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  */
  57 extern int wf_register_control(struct wf_control *ct);
  58 extern void wf_unregister_control(struct wf_control *ct);
  59 extern struct wf_control * wf_find_control(const char *name);
  60 extern int wf_get_control(struct wf_control *ct);
  61 extern void wf_put_control(struct wf_control *ct);
  62
  63 static 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
  69 static 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
  79 struct wf_sensor;
  80
  81 struct 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
  87 struct 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 */
  96 extern int wf_register_sensor(struct wf_sensor *sr);
  97 extern void wf_unregister_sensor(struct wf_sensor *sr);
  98 extern struct wf_sensor * wf_find_sensor(const char *name);
  99 extern int wf_get_sensor(struct wf_sensor *sr);
 100 extern 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  */
 114 extern int wf_register_client(struct notifier_block *nb);
 115 extern int wf_unregister_client(struct notifier_block *nb);
 116
 117 /* Overtemp conditions. Those are refcounted */
 118 extern void wf_set_overtemp(void);
 119 extern void wf_clear_overtemp(void);
 120 extern 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__ */