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__ */ 132