aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/mach-voyager/voyager_thread.c
blob: c69c931818ed49b8d5d9326a50aefb8aa339ba9e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/* -*- mode: c; c-basic-offset: 8 -*- */

/* Copyright (C) 2001
 *
 * Author: J.E.J.Bottomley@HansenPartnership.com
 *
 * linux/arch/i386/kernel/voyager_thread.c
 *
 * This module provides the machine status monitor thread for the
 * voyager architecture.  This allows us to monitor the machine
 * environment (temp, voltage, fan function) and the front panel and
 * internal UPS.  If a fault is detected, this thread takes corrective
 * action (usually just informing init)
 * */

#include <linux/module.h>
#include <linux/mm.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/mc146818rtc.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/kmod.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/kthread.h>
#include <asm/desc.h>
#include <asm/voyager.h>
#include <asm/vic.h>
#include <asm/mtrr.h>
#include <asm/msr.h>

struct task_struct *voyager_thread;
static __u8 set_timeout;

static int execute(const char *string)
{
	int ret;

	char *envp[] = {
		"HOME=/",
		"TERM=linux",
		"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
		NULL,
	};
	char *argv[] = {
		"/bin/bash",
		"-c",
		(char *)string,
		NULL,
	};

	if ((ret =
	     call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC)) != 0) {
		printk(KERN_ERR "Voyager failed to run \"%s\": %i\n", string,
		       ret);
	}
	return ret;
}

static void check_from_kernel(void)
{
	if (voyager_status.switch_off) {

		/* FIXME: This should be configurable via proc */
		execute("umask 600; echo 0 > /etc/initrunlvl; kill -HUP 1");
	} else if (voyager_status.power_fail) {
		VDEBUG(("Voyager daemon detected AC power failure\n"));

		/* FIXME: This should be configureable via proc */
		execute("umask 600; echo F > /etc/powerstatus; kill -PWR 1");
		set_timeout = 1;
	}
}

static void check_continuing_condition(void)
{
	if (voyager_status.power_fail) {
		__u8 data;
		voyager_cat_psi(VOYAGER_PSI_SUBREAD,
				VOYAGER_PSI_AC_FAIL_REG, &data);
		if ((data & 0x1f) == 0) {
			/* all power restored */
			printk(KERN_NOTICE
			       "VOYAGER AC power restored, cancelling shutdown\n");
			/* FIXME: should be user configureable */
			execute
			    ("umask 600; echo O > /etc/powerstatus; kill -PWR 1");
			set_timeout = 0;
		}
	}
}

static int thread(void *unused)
{
	printk(KERN_NOTICE "Voyager starting monitor thread\n");

	for (;;) {
		set_current_state(TASK_INTERRUPTIBLE);
		schedule_timeout(set_timeout ? HZ : MAX_SCHEDULE_TIMEOUT);

		VDEBUG(("Voyager Daemon awoken\n"));
		if (voyager_status.request_from_kernel == 0) {
			/* probably awoken from timeout */
			check_continuing_condition();
		} else {
			check_from_kernel();
			voyager_status.request_from_kernel = 0;
		}
	}
}

static int __init voyager_thread_start(void)
{
	voyager_thread = kthread_run(thread, NULL, "kvoyagerd");
	if (IS_ERR(voyager_thread)) {
		printk(KERN_ERR
		       "Voyager: Failed to create system monitor thread.\n");
		return PTR_ERR(voyager_thread);
	}
	return 0;
}

static void __exit voyager_thread_stop(void)
{
	kthread_stop(voyager_thread);
}

module_init(voyager_thread_start);
module_exit(voyager_thread_stop);