xref: /linux/include/uapi/linux/rtc.h (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
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 _UAPI_LINUX_RTC_H_
13 #define _UAPI_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 
25 struct 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  */
41 struct 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 
60 struct 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 
70 struct 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 /* _UAPI_LINUX_RTC_H_ */
153