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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * Windfarm PowerMac thermal control.4 *5 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.6 * <benh@kernel.crashing.org>7 */8 9#ifndef __WINDFARM_H__10#define __WINDFARM_H__11 12#include <linux/kref.h>13#include <linux/list.h>14#include <linux/module.h>15#include <linux/notifier.h>16#include <linux/device.h>17 18/* Display a 16.16 fixed point value */19#define FIX32TOPRINT(f) (((s32)(f)) >> 16),(((((s32)(f)) & 0xffff) * 1000) >> 16)20 21/*22 * Control objects23 */24 25struct wf_control;26 27struct 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 36struct wf_control {37 struct list_head link;38 const struct wf_control_ops *ops;39 const char *name;40 int type;41 struct kref ref;42 struct device_attribute attr;43 void *priv;44};45 46#define WF_CONTROL_TYPE_GENERIC 047#define WF_CONTROL_RPM_FAN 148#define WF_CONTROL_PWM_FAN 249 50 51/* Note about lifetime rules: wf_register_control() will initialize52 * the kref and wf_unregister_control will decrement it, thus the53 * object creating/disposing a given control shouldn't assume it54 * still exists after wf_unregister_control has been called.55 */56extern int wf_register_control(struct wf_control *ct);57extern void wf_unregister_control(struct wf_control *ct);58extern int wf_get_control(struct wf_control *ct);59extern void wf_put_control(struct wf_control *ct);60 61static 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 67static 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 73static inline int wf_control_set(struct wf_control *ct, s32 val)74{75 return ct->ops->set_value(ct, val);76}77 78static inline int wf_control_get(struct wf_control *ct, s32 *val)79{80 return ct->ops->get_value(ct, val);81}82 83static inline s32 wf_control_get_min(struct wf_control *ct)84{85 return ct->ops->get_min(ct);86}87 88static inline s32 wf_control_get_max(struct wf_control *ct)89{90 return ct->ops->get_max(ct);91}92 93/*94 * Sensor objects95 */96 97struct wf_sensor;98 99struct wf_sensor_ops {100 int (*get_value)(struct wf_sensor *sr, s32 *val);101 void (*release)(struct wf_sensor *sr);102 struct module *owner;103};104 105struct wf_sensor {106 struct list_head link;107 const struct wf_sensor_ops *ops;108 const char *name;109 struct kref ref;110 struct device_attribute attr;111 void *priv;112};113 114/* Same lifetime rules as controls */115extern int wf_register_sensor(struct wf_sensor *sr);116extern void wf_unregister_sensor(struct wf_sensor *sr);117extern int wf_get_sensor(struct wf_sensor *sr);118extern void wf_put_sensor(struct wf_sensor *sr);119 120static inline int wf_sensor_get(struct wf_sensor *sr, s32 *val)121{122 return sr->ops->get_value(sr, val);123}124 125/* For use by clients. Note that we are a bit racy here since126 * notifier_block doesn't have a module owner field. I may fix127 * it one day ...128 *129 * LOCKING NOTE !130 *131 * All "events" except WF_EVENT_TICK are called with an internal mutex132 * held which will deadlock if you call basically any core routine.133 * So don't ! Just take note of the event and do your actual operations134 * from the ticker.135 *136 */137extern int wf_register_client(struct notifier_block *nb);138extern int wf_unregister_client(struct notifier_block *nb);139 140/* Overtemp conditions. Those are refcounted */141extern void wf_set_overtemp(void);142extern void wf_clear_overtemp(void);143 144#define WF_EVENT_NEW_CONTROL 0 /* param is wf_control * */145#define WF_EVENT_NEW_SENSOR 1 /* param is wf_sensor * */146#define WF_EVENT_OVERTEMP 2 /* no param */147#define WF_EVENT_NORMALTEMP 3 /* overtemp condition cleared */148#define WF_EVENT_TICK 4 /* 1 second tick */149 150/* Note: If that driver gets more broad use, we could replace the151 * simplistic overtemp bits with "environmental conditions". That152 * could then be used to also notify of things like fan failure,153 * case open, battery conditions, ...154 */155 156#endif /* __WINDFARM_H__ */157