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__ */ 162