1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2/*
  3 * Generic RTC interface.
  4 * This version contains the part of the user interface to the Real Time Clock
  5 * service. It is used with both the legacy mc146818 and also  EFI
  6 * Struct rtc_time and first 12 ioctl by Paul Gortmaker, 1996 - separated out
  7 * from <linux/mc146818rtc.h> to this file for 2.4 kernels.
  8 *
  9 * Copyright (C) 1999 Hewlett-Packard Co.
 10 * Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com>
 11 */
 12#ifndef _LINUX_RTC_H_
 13#define _LINUX_RTC_H_
 14
 15#include <linux/const.h>
 16#include <linux/ioctl.h>
 17#include <linux/types.h>
 18
 19/*
 20 * The struct used to pass data via the following ioctl. Similar to the
 21 * struct tm in <time.h>, but it needs to be here so that the kernel
 22 * source is self contained, allowing cross-compiles, etc. etc.
 23 */
 24
 25struct rtc_time {
 26	int tm_sec;
 27	int tm_min;
 28	int tm_hour;
 29	int tm_mday;
 30	int tm_mon;
 31	int tm_year;
 32	int tm_wday;
 33	int tm_yday;
 34	int tm_isdst;
 35};
 36
 37/*
 38 * This data structure is inspired by the EFI (v0.92) wakeup
 39 * alarm API.
 40 */
 41struct rtc_wkalrm {
 42	unsigned char enabled;	/* 0 = alarm disabled, 1 = alarm enabled */
 43	unsigned char pending;  /* 0 = alarm not pending, 1 = alarm pending */
 44	struct rtc_time time;	/* time the alarm is set to */
 45};
 46
 47/*
 48 * Data structure to control PLL correction some better RTC feature
 49 * pll_value is used to get or set current value of correction,
 50 * the rest of the struct is used to query HW capabilities.
 51 * This is modeled after the RTC used in Q40/Q60 computers but
 52 * should be sufficiently flexible for other devices
 53 *
 54 * +ve pll_value means clock will run faster by
 55 *   pll_value*pll_posmult/pll_clock
 56 * -ve pll_value means clock will run slower by
 57 *   pll_value*pll_negmult/pll_clock
 58 */
 59
 60struct rtc_pll_info {
 61	int pll_ctrl;       /* placeholder for fancier control */
 62	int pll_value;      /* get/set correction value */
 63	int pll_max;        /* max +ve (faster) adjustment value */
 64	int pll_min;        /* max -ve (slower) adjustment value */
 65	int pll_posmult;    /* factor for +ve correction */
 66	int pll_negmult;    /* factor for -ve correction */
 67	long pll_clock;     /* base PLL frequency */
 68};
 69
 70struct rtc_param {
 71	__u64 param;
 72	union {
 73		__u64 uvalue;
 74		__s64 svalue;
 75		__u64 ptr;
 76	};
 77	__u32 index;
 78	__u32 __pad;
 79};
 80
 81/*
 82 * ioctl calls that are permitted to the /dev/rtc interface, if
 83 * any of the RTC drivers are enabled.
 84 */
 85
 86#define RTC_AIE_ON	_IO('p', 0x01)	/* Alarm int. enable on		*/
 87#define RTC_AIE_OFF	_IO('p', 0x02)	/* ... off			*/
 88#define RTC_UIE_ON	_IO('p', 0x03)	/* Update int. enable on	*/
 89#define RTC_UIE_OFF	_IO('p', 0x04)	/* ... off			*/
 90#define RTC_PIE_ON	_IO('p', 0x05)	/* Periodic int. enable on	*/
 91#define RTC_PIE_OFF	_IO('p', 0x06)	/* ... off			*/
 92#define RTC_WIE_ON	_IO('p', 0x0f)  /* Watchdog int. enable on	*/
 93#define RTC_WIE_OFF	_IO('p', 0x10)  /* ... off			*/
 94
 95#define RTC_ALM_SET	_IOW('p', 0x07, struct rtc_time) /* Set alarm time  */
 96#define RTC_ALM_READ	_IOR('p', 0x08, struct rtc_time) /* Read alarm time */
 97#define RTC_RD_TIME	_IOR('p', 0x09, struct rtc_time) /* Read RTC time   */
 98#define RTC_SET_TIME	_IOW('p', 0x0a, struct rtc_time) /* Set RTC time    */
 99#define RTC_IRQP_READ	_IOR('p', 0x0b, unsigned long)	 /* Read IRQ rate   */
100#define RTC_IRQP_SET	_IOW('p', 0x0c, unsigned long)	 /* Set IRQ rate    */
101#define RTC_EPOCH_READ	_IOR('p', 0x0d, unsigned long)	 /* Read epoch      */
102#define RTC_EPOCH_SET	_IOW('p', 0x0e, unsigned long)	 /* Set epoch       */
103
104#define RTC_WKALM_SET	_IOW('p', 0x0f, struct rtc_wkalrm)/* Set wakeup alarm*/
105#define RTC_WKALM_RD	_IOR('p', 0x10, struct rtc_wkalrm)/* Get wakeup alarm*/
106
107#define RTC_PLL_GET	_IOR('p', 0x11, struct rtc_pll_info)  /* Get PLL correction */
108#define RTC_PLL_SET	_IOW('p', 0x12, struct rtc_pll_info)  /* Set PLL correction */
109
110#define RTC_PARAM_GET	_IOW('p', 0x13, struct rtc_param)  /* Get parameter */
111#define RTC_PARAM_SET	_IOW('p', 0x14, struct rtc_param)  /* Set parameter */
112
113#define RTC_VL_DATA_INVALID	_BITUL(0) /* Voltage too low, RTC data is invalid */
114#define RTC_VL_BACKUP_LOW	_BITUL(1) /* Backup voltage is low */
115#define RTC_VL_BACKUP_EMPTY	_BITUL(2) /* Backup empty or not present */
116#define RTC_VL_ACCURACY_LOW	_BITUL(3) /* Voltage is low, RTC accuracy is reduced */
117#define RTC_VL_BACKUP_SWITCH	_BITUL(4) /* Backup switchover happened */
118
119#define RTC_VL_READ	_IOR('p', 0x13, unsigned int)	/* Voltage low detection */
120#define RTC_VL_CLR	_IO('p', 0x14)		/* Clear voltage low information */
121
122/* interrupt flags */
123#define RTC_IRQF 0x80	/* Any of the following is active */
124#define RTC_PF 0x40	/* Periodic interrupt */
125#define RTC_AF 0x20	/* Alarm interrupt */
126#define RTC_UF 0x10	/* Update interrupt for 1Hz RTC */
127
128/* feature list */
129#define RTC_FEATURE_ALARM		0
130#define RTC_FEATURE_ALARM_RES_MINUTE	1
131#define RTC_FEATURE_NEED_WEEK_DAY	2
132#define RTC_FEATURE_ALARM_RES_2S	3
133#define RTC_FEATURE_UPDATE_INTERRUPT	4
134#define RTC_FEATURE_CORRECTION		5
135#define RTC_FEATURE_BACKUP_SWITCH_MODE	6
136#define RTC_FEATURE_ALARM_WAKEUP_ONLY	7
137#define RTC_FEATURE_CNT			8
138
139/* parameter list */
140#define RTC_PARAM_FEATURES		0
141#define RTC_PARAM_CORRECTION		1
142#define RTC_PARAM_BACKUP_SWITCH_MODE	2
143
144#define RTC_BSM_DISABLED	0
145#define RTC_BSM_DIRECT		1
146#define RTC_BSM_LEVEL		2
147#define RTC_BSM_STANDBY		3
148
149#define RTC_MAX_FREQ	8192
150
151
152#endif /* _LINUX_RTC_H_ */