2b03884fdb2a968a904ca08f29c9f8c017e22788
[linux-2.6.git] / arch / i386 / mach-voyager / voyager_thread.c
1 /* -*- mode: c; c-basic-offset: 8 -*- */
2
3 /* Copyright (C) 2001
4  *
5  * Author: J.E.J.Bottomley@HansenPartnership.com
6  *
7  * linux/arch/i386/kernel/voyager_thread.c
8  *
9  * This module provides the machine status monitor thread for the
10  * voyager architecture.  This allows us to monitor the machine
11  * environment (temp, voltage, fan function) and the front panel and
12  * internal UPS.  If a fault is detected, this thread takes corrective
13  * action (usually just informing init)
14  * */
15
16 #include <linux/module.h>
17 #include <linux/config.h>
18 #include <linux/mm.h>
19 #include <linux/kernel_stat.h>
20 #include <linux/delay.h>
21 #include <linux/mc146818rtc.h>
22 #include <linux/smp_lock.h>
23 #include <linux/init.h>
24 #include <linux/bootmem.h>
25 #include <linux/kmod.h>
26 #include <linux/completion.h>
27 #include <linux/sched.h>
28 #include <asm/desc.h>
29 #include <asm/voyager.h>
30 #include <asm/vic.h>
31 #include <asm/mtrr.h>
32 #include <asm/msr.h>
33
34 #define THREAD_NAME "kvoyagerd"
35
36 /* external variables */
37 int kvoyagerd_running = 0;
38 DECLARE_MUTEX_LOCKED(kvoyagerd_sem);
39
40 static int thread(void *);
41
42 static __u8 set_timeout = 0;
43
44 /* Start the machine monitor thread.  Return 1 if OK, 0 if fail */
45 static int __init
46 voyager_thread_start(void)
47 {
48         if(kernel_thread(thread, NULL, CLONE_KERNEL) < 0) {
49                 /* This is serious, but not fatal */
50                 printk(KERN_ERR "Voyager: Failed to create system monitor thread!!!\n");
51                 return 1;
52         }
53         return 0;
54 }
55
56 static int
57 execute(const char *string)
58 {
59         int ret;
60
61         char *envp[] = {
62                 "HOME=/",
63                 "TERM=linux",
64                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
65                 NULL,
66         };
67         char *argv[] = {
68                 "/bin/bash",
69                 "-c",
70                 (char *)string,
71                 NULL,
72         };
73
74         if ((ret = call_usermodehelper(argv[0], argv, envp, 1)) != 0) {
75                 printk(KERN_ERR "Voyager failed to run \"%s\": %i\n",
76                        string, ret);
77         }
78         return ret;
79 }
80
81 static void
82 check_from_kernel(void)
83 {
84         if(voyager_status.switch_off) {
85                 
86                 /* FIXME: This should be configureable via proc */
87                 execute("umask 600; echo 0 > /etc/initrunlvl; kill -HUP 1");
88         } else if(voyager_status.power_fail) {
89                 VDEBUG(("Voyager daemon detected AC power failure\n"));
90                 
91                 /* FIXME: This should be configureable via proc */
92                 execute("umask 600; echo F > /etc/powerstatus; kill -PWR 1");
93                 set_timeout = 1;
94         }
95 }
96
97 static void
98 check_continuing_condition(void)
99 {
100         if(voyager_status.power_fail) {
101                 __u8 data;
102                 voyager_cat_psi(VOYAGER_PSI_SUBREAD, 
103                                 VOYAGER_PSI_AC_FAIL_REG, &data);
104                 if((data & 0x1f) == 0) {
105                         /* all power restored */
106                         printk(KERN_NOTICE "VOYAGER AC power restored, cancelling shutdown\n");
107                         /* FIXME: should be user configureable */
108                         execute("umask 600; echo O > /etc/powerstatus; kill -PWR 1");
109                         set_timeout = 0;
110                 }
111         }
112 }
113
114 static void
115 wakeup(unsigned long unused)
116 {
117         up(&kvoyagerd_sem);
118 }
119
120 static int
121 thread(void *unused)
122 {
123         struct timer_list wakeup_timer;
124
125         kvoyagerd_running = 1;
126
127         daemonize(THREAD_NAME);
128
129         set_timeout = 0;
130
131         init_timer(&wakeup_timer);
132
133         sigfillset(&current->blocked);
134         current->signal->tty = NULL;
135
136         printk(KERN_NOTICE "Voyager starting monitor thread\n");
137
138         for(;;) {
139                 down_interruptible(&kvoyagerd_sem);
140                 VDEBUG(("Voyager Daemon awoken\n"));
141                 if(voyager_status.request_from_kernel == 0) {
142                         /* probably awoken from timeout */
143                         check_continuing_condition();
144                 } else {
145                         check_from_kernel();
146                         voyager_status.request_from_kernel = 0;
147                 }
148                 if(set_timeout) {
149                         del_timer(&wakeup_timer);
150                         wakeup_timer.expires = HZ + jiffies;
151                         wakeup_timer.function = wakeup;
152                         add_timer(&wakeup_timer);
153                 }
154         }
155 }
156
157 static void __exit
158 voyager_thread_stop(void)
159 {
160         /* FIXME: do nothing at the moment */
161 }
162
163 module_init(voyager_thread_start);
164 //module_exit(voyager_thread_stop);