xref: /linux-6.15/include/linux/watchdog.h (revision db4e8395)
1 /*
2  *	Generic watchdog defines. Derived from..
3  *
4  * Berkshire PC Watchdog Defines
5  * by Ken Hollis <[email protected]>
6  *
7  */
8 
9 #ifndef _LINUX_WATCHDOG_H
10 #define _LINUX_WATCHDOG_H
11 
12 #include <linux/ioctl.h>
13 #include <linux/types.h>
14 
15 #define	WATCHDOG_IOCTL_BASE	'W'
16 
17 struct watchdog_info {
18 	__u32 options;		/* Options the card/driver supports */
19 	__u32 firmware_version;	/* Firmware version of the card */
20 	__u8  identity[32];	/* Identity of the board */
21 };
22 
23 #define	WDIOC_GETSUPPORT	_IOR(WATCHDOG_IOCTL_BASE, 0, struct watchdog_info)
24 #define	WDIOC_GETSTATUS		_IOR(WATCHDOG_IOCTL_BASE, 1, int)
25 #define	WDIOC_GETBOOTSTATUS	_IOR(WATCHDOG_IOCTL_BASE, 2, int)
26 #define	WDIOC_GETTEMP		_IOR(WATCHDOG_IOCTL_BASE, 3, int)
27 #define	WDIOC_SETOPTIONS	_IOR(WATCHDOG_IOCTL_BASE, 4, int)
28 #define	WDIOC_KEEPALIVE		_IOR(WATCHDOG_IOCTL_BASE, 5, int)
29 #define	WDIOC_SETTIMEOUT        _IOWR(WATCHDOG_IOCTL_BASE, 6, int)
30 #define	WDIOC_GETTIMEOUT        _IOR(WATCHDOG_IOCTL_BASE, 7, int)
31 #define	WDIOC_SETPRETIMEOUT	_IOWR(WATCHDOG_IOCTL_BASE, 8, int)
32 #define	WDIOC_GETPRETIMEOUT	_IOR(WATCHDOG_IOCTL_BASE, 9, int)
33 #define	WDIOC_GETTIMELEFT	_IOR(WATCHDOG_IOCTL_BASE, 10, int)
34 
35 #define	WDIOF_UNKNOWN		-1	/* Unknown flag error */
36 #define	WDIOS_UNKNOWN		-1	/* Unknown status error */
37 
38 #define	WDIOF_OVERHEAT		0x0001	/* Reset due to CPU overheat */
39 #define	WDIOF_FANFAULT		0x0002	/* Fan failed */
40 #define	WDIOF_EXTERN1		0x0004	/* External relay 1 */
41 #define	WDIOF_EXTERN2		0x0008	/* External relay 2 */
42 #define	WDIOF_POWERUNDER	0x0010	/* Power bad/power fault */
43 #define	WDIOF_CARDRESET		0x0020	/* Card previously reset the CPU */
44 #define	WDIOF_POWEROVER		0x0040	/* Power over voltage */
45 #define	WDIOF_SETTIMEOUT	0x0080  /* Set timeout (in seconds) */
46 #define	WDIOF_MAGICCLOSE	0x0100	/* Supports magic close char */
47 #define	WDIOF_PRETIMEOUT	0x0200  /* Pretimeout (in seconds), get/set */
48 #define	WDIOF_KEEPALIVEPING	0x8000	/* Keep alive ping reply */
49 
50 #define	WDIOS_DISABLECARD	0x0001	/* Turn off the watchdog timer */
51 #define	WDIOS_ENABLECARD	0x0002	/* Turn on the watchdog timer */
52 #define	WDIOS_TEMPPANIC		0x0004	/* Kernel panic on temperature trip */
53 
54 #ifdef __KERNEL__
55 
56 #ifdef CONFIG_WATCHDOG_NOWAYOUT
57 #define WATCHDOG_NOWAYOUT	1
58 #else
59 #define WATCHDOG_NOWAYOUT	0
60 #endif
61 
62 struct watchdog_ops;
63 struct watchdog_device;
64 
65 /** struct watchdog_ops - The watchdog-devices operations
66  *
67  * @owner:	The module owner.
68  * @start:	The routine for starting the watchdog device.
69  * @stop:	The routine for stopping the watchdog device.
70  * @ping:	The routine that sends a keepalive ping to the watchdog device.
71  * @status:	The routine that shows the status of the watchdog device.
72  * @set_timeout:The routine for setting the watchdog devices timeout value.
73  * @ioctl:	The routines that handles extra ioctl calls.
74  *
75  * The watchdog_ops structure contains a list of low-level operations
76  * that control a watchdog device. It also contains the module that owns
77  * these operations. The start and stop function are mandatory, all other
78  * functions are optonal.
79  */
80 struct watchdog_ops {
81 	struct module *owner;
82 	/* mandatory operations */
83 	int (*start)(struct watchdog_device *);
84 	int (*stop)(struct watchdog_device *);
85 	/* optional operations */
86 	int (*ping)(struct watchdog_device *);
87 	unsigned int (*status)(struct watchdog_device *);
88 	int (*set_timeout)(struct watchdog_device *, unsigned int);
89 	long (*ioctl)(struct watchdog_device *, unsigned int, unsigned long);
90 };
91 
92 /** struct watchdog_device - The structure that defines a watchdog device
93  *
94  * @info:	Pointer to a watchdog_info structure.
95  * @ops:	Pointer to the list of watchdog operations.
96  * @bootstatus:	Status of the watchdog device at boot.
97  * @timeout:	The watchdog devices timeout value.
98  * @min_timeout:The watchdog devices minimum timeout value.
99  * @max_timeout:The watchdog devices maximum timeout value.
100  * @driver-data:Pointer to the drivers private data.
101  * @status:	Field that contains the devices internal status bits.
102  *
103  * The watchdog_device structure contains all information about a
104  * watchdog timer device.
105  *
106  * The driver-data field may not be accessed directly. It must be accessed
107  * via the watchdog_set_drvdata and watchdog_get_drvdata helpers.
108  */
109 struct watchdog_device {
110 	const struct watchdog_info *info;
111 	const struct watchdog_ops *ops;
112 	unsigned int bootstatus;
113 	unsigned int timeout;
114 	unsigned int min_timeout;
115 	unsigned int max_timeout;
116 	void *driver_data;
117 	unsigned long status;
118 /* Bit numbers for status flags */
119 #define WDOG_ACTIVE		0	/* Is the watchdog running/active */
120 #define WDOG_DEV_OPEN		1	/* Opened via /dev/watchdog ? */
121 #define WDOG_ALLOW_RELEASE	2	/* Did we receive the magic char ? */
122 #define WDOG_NO_WAY_OUT		3	/* Is 'nowayout' feature set ? */
123 };
124 
125 /* Use the following functions to manipulate watchdog driver specific data */
126 static inline void watchdog_set_drvdata(struct watchdog_device *wdd, void *data)
127 {
128 	wdd->driver_data = data;
129 }
130 
131 static inline void *watchdog_get_drvdata(struct watchdog_device *wdd)
132 {
133 	return wdd->driver_data;
134 }
135 
136 /* drivers/watchdog/core/watchdog_core.c */
137 extern int watchdog_register_device(struct watchdog_device *);
138 extern void watchdog_unregister_device(struct watchdog_device *);
139 
140 #endif	/* __KERNEL__ */
141 
142 #endif  /* ifndef _LINUX_WATCHDOG_H */
143