1 /*
2  *	Generic watchdog defines. Derived from..
3  *
4  * Berkshire PC Watchdog Defines
5  * by Ken Hollis <khollis@bitgate.com>
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 #include <linux/bitops.h>
57 
58 struct watchdog_ops;
59 struct watchdog_device;
60 
61 /** struct watchdog_ops - The watchdog-devices operations
62  *
63  * @owner:	The module owner.
64  * @start:	The routine for starting the watchdog device.
65  * @stop:	The routine for stopping the watchdog device.
66  * @ping:	The routine that sends a keepalive ping to the watchdog device.
67  * @status:	The routine that shows the status of the watchdog device.
68  * @set_timeout:The routine for setting the watchdog devices timeout value.
69  * @get_timeleft:The routine that get's the time that's left before a reset.
70  * @ioctl:	The routines that handles extra ioctl calls.
71  *
72  * The watchdog_ops structure contains a list of low-level operations
73  * that control a watchdog device. It also contains the module that owns
74  * these operations. The start and stop function are mandatory, all other
75  * functions are optonal.
76  */
77 struct watchdog_ops {
78 	struct module *owner;
79 	/* mandatory operations */
80 	int (*start)(struct watchdog_device *);
81 	int (*stop)(struct watchdog_device *);
82 	/* optional operations */
83 	int (*ping)(struct watchdog_device *);
84 	unsigned int (*status)(struct watchdog_device *);
85 	int (*set_timeout)(struct watchdog_device *, unsigned int);
86 	unsigned int (*get_timeleft)(struct watchdog_device *);
87 	long (*ioctl)(struct watchdog_device *, unsigned int, unsigned long);
88 };
89 
90 /** struct watchdog_device - The structure that defines a watchdog device
91  *
92  * @info:	Pointer to a watchdog_info structure.
93  * @ops:	Pointer to the list of watchdog operations.
94  * @bootstatus:	Status of the watchdog device at boot.
95  * @timeout:	The watchdog devices timeout value.
96  * @min_timeout:The watchdog devices minimum timeout value.
97  * @max_timeout:The watchdog devices maximum timeout value.
98  * @driver-data:Pointer to the drivers private data.
99  * @status:	Field that contains the devices internal status bits.
100  *
101  * The watchdog_device structure contains all information about a
102  * watchdog timer device.
103  *
104  * The driver-data field may not be accessed directly. It must be accessed
105  * via the watchdog_set_drvdata and watchdog_get_drvdata helpers.
106  */
107 struct watchdog_device {
108 	const struct watchdog_info *info;
109 	const struct watchdog_ops *ops;
110 	unsigned int bootstatus;
111 	unsigned int timeout;
112 	unsigned int min_timeout;
113 	unsigned int max_timeout;
114 	void *driver_data;
115 	unsigned long status;
116 /* Bit numbers for status flags */
117 #define WDOG_ACTIVE		0	/* Is the watchdog running/active */
118 #define WDOG_DEV_OPEN		1	/* Opened via /dev/watchdog ? */
119 #define WDOG_ALLOW_RELEASE	2	/* Did we receive the magic char ? */
120 #define WDOG_NO_WAY_OUT		3	/* Is 'nowayout' feature set ? */
121 };
122 
123 #ifdef CONFIG_WATCHDOG_NOWAYOUT
124 #define WATCHDOG_NOWAYOUT		1
125 #define WATCHDOG_NOWAYOUT_INIT_STATUS	(1 << WDOG_NO_WAY_OUT)
126 #else
127 #define WATCHDOG_NOWAYOUT		0
128 #define WATCHDOG_NOWAYOUT_INIT_STATUS	0
129 #endif
130 
131 /* Use the following function to set the nowayout feature */
watchdog_set_nowayout(struct watchdog_device * wdd,bool nowayout)132 static inline void watchdog_set_nowayout(struct watchdog_device *wdd, bool nowayout)
133 {
134 	if (nowayout)
135 		set_bit(WDOG_NO_WAY_OUT, &wdd->status);
136 }
137 
138 /* Use the following functions to manipulate watchdog driver specific data */
watchdog_set_drvdata(struct watchdog_device * wdd,void * data)139 static inline void watchdog_set_drvdata(struct watchdog_device *wdd, void *data)
140 {
141 	wdd->driver_data = data;
142 }
143 
watchdog_get_drvdata(struct watchdog_device * wdd)144 static inline void *watchdog_get_drvdata(struct watchdog_device *wdd)
145 {
146 	return wdd->driver_data;
147 }
148 
149 /* drivers/watchdog/core/watchdog_core.c */
150 extern int watchdog_register_device(struct watchdog_device *);
151 extern void watchdog_unregister_device(struct watchdog_device *);
152 
153 #endif	/* __KERNEL__ */
154 
155 #endif  /* ifndef _LINUX_WATCHDOG_H */
156