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 
18 /*
19  * The struct used to pass data via the following ioctl. Similar to the
20  * struct tm in <time.h>, but it needs to be here so that the kernel
21  * source is self contained, allowing cross-compiles, etc. etc.
22  */
23 
24 struct rtc_time {
25 	int tm_sec;
26 	int tm_min;
27 	int tm_hour;
28 	int tm_mday;
29 	int tm_mon;
30 	int tm_year;
31 	int tm_wday;
32 	int tm_yday;
33 	int tm_isdst;
34 };
35 
36 /*
37  * This data structure is inspired by the EFI (v0.92) wakeup
38  * alarm API.
39  */
40 struct rtc_wkalrm {
41 	unsigned char enabled;	/* 0 = alarm disabled, 1 = alarm enabled */
42 	unsigned char pending;  /* 0 = alarm not pending, 1 = alarm pending */
43 	struct rtc_time time;	/* time the alarm is set to */
44 };
45 
46 /*
47  * Data structure to control PLL correction some better RTC feature
48  * pll_value is used to get or set current value of correction,
49  * the rest of the struct is used to query HW capabilities.
50  * This is modeled after the RTC used in Q40/Q60 computers but
51  * should be sufficiently flexible for other devices
52  *
53  * +ve pll_value means clock will run faster by
54  *   pll_value*pll_posmult/pll_clock
55  * -ve pll_value means clock will run slower by
56  *   pll_value*pll_negmult/pll_clock
57  */
58 
59 struct rtc_pll_info {
60 	int pll_ctrl;       /* placeholder for fancier control */
61 	int pll_value;      /* get/set correction value */
62 	int pll_max;        /* max +ve (faster) adjustment value */
63 	int pll_min;        /* max -ve (slower) adjustment value */
64 	int pll_posmult;    /* factor for +ve correction */
65 	int pll_negmult;    /* factor for -ve correction */
66 	long pll_clock;     /* base PLL frequency */
67 };
68 
69 /*
70  * ioctl calls that are permitted to the /dev/rtc interface, if
71  * any of the RTC drivers are enabled.
72  */
73 
74 #define RTC_AIE_ON	_IO('p', 0x01)	/* Alarm int. enable on		*/
75 #define RTC_AIE_OFF	_IO('p', 0x02)	/* ... off			*/
76 #define RTC_UIE_ON	_IO('p', 0x03)	/* Update int. enable on	*/
77 #define RTC_UIE_OFF	_IO('p', 0x04)	/* ... off			*/
78 #define RTC_PIE_ON	_IO('p', 0x05)	/* Periodic int. enable on	*/
79 #define RTC_PIE_OFF	_IO('p', 0x06)	/* ... off			*/
80 #define RTC_WIE_ON	_IO('p', 0x0f)  /* Watchdog int. enable on	*/
81 #define RTC_WIE_OFF	_IO('p', 0x10)  /* ... off			*/
82 
83 #define RTC_ALM_SET	_IOW('p', 0x07, struct rtc_time) /* Set alarm time  */
84 #define RTC_ALM_READ	_IOR('p', 0x08, struct rtc_time) /* Read alarm time */
85 #define RTC_RD_TIME	_IOR('p', 0x09, struct rtc_time) /* Read RTC time   */
86 #define RTC_SET_TIME	_IOW('p', 0x0a, struct rtc_time) /* Set RTC time    */
87 #define RTC_IRQP_READ	_IOR('p', 0x0b, unsigned long)	 /* Read IRQ rate   */
88 #define RTC_IRQP_SET	_IOW('p', 0x0c, unsigned long)	 /* Set IRQ rate    */
89 #define RTC_EPOCH_READ	_IOR('p', 0x0d, unsigned long)	 /* Read epoch      */
90 #define RTC_EPOCH_SET	_IOW('p', 0x0e, unsigned long)	 /* Set epoch       */
91 
92 #define RTC_WKALM_SET	_IOW('p', 0x0f, struct rtc_wkalrm)/* Set wakeup alarm*/
93 #define RTC_WKALM_RD	_IOR('p', 0x10, struct rtc_wkalrm)/* Get wakeup alarm*/
94 
95 #define RTC_PLL_GET	_IOR('p', 0x11, struct rtc_pll_info)  /* Get PLL correction */
96 #define RTC_PLL_SET	_IOW('p', 0x12, struct rtc_pll_info)  /* Set PLL correction */
97 
98 #define RTC_VL_DATA_INVALID	_BITUL(0) /* Voltage too low, RTC data is invalid */
99 #define RTC_VL_BACKUP_LOW	_BITUL(1) /* Backup voltage is low */
100 #define RTC_VL_BACKUP_EMPTY	_BITUL(2) /* Backup empty or not present */
101 #define RTC_VL_ACCURACY_LOW	_BITUL(3) /* Voltage is low, RTC accuracy is reduced */
102 #define RTC_VL_BACKUP_SWITCH	_BITUL(4) /* Backup switchover happened */
103 
104 #define RTC_VL_READ	_IOR('p', 0x13, unsigned int)	/* Voltage low detection */
105 #define RTC_VL_CLR	_IO('p', 0x14)		/* Clear voltage low information */
106 
107 /* interrupt flags */
108 #define RTC_IRQF 0x80	/* Any of the following is active */
109 #define RTC_PF 0x40	/* Periodic interrupt */
110 #define RTC_AF 0x20	/* Alarm interrupt */
111 #define RTC_UF 0x10	/* Update interrupt for 1Hz RTC */
112 
113 /* feature list */
114 #define RTC_FEATURE_ALARM		0
115 #define RTC_FEATURE_ALARM_RES_MINUTE	1
116 #define RTC_FEATURE_NEED_WEEK_DAY	2
117 #define RTC_FEATURE_CNT			3
118 
119 #define RTC_MAX_FREQ	8192
120 
121 
122 #endif /* _UAPI_LINUX_RTC_H_ */
123