Linux-2.6.12-rc2
[linux-3.10.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 #include <linux/irq.h>
35
36 #define THREAD_NAME "kvoyagerd"
37
38 /* external variables */
39 int kvoyagerd_running = 0;
40 DECLARE_MUTEX_LOCKED(kvoyagerd_sem);
41
42 static int thread(void *);
43
44 static __u8 set_timeout = 0;
45
46 /* Start the machine monitor thread.  Return 1 if OK, 0 if fail */
47 static int __init
48 voyager_thread_start(void)
49 {
50         if(kernel_thread(thread, NULL, CLONE_KERNEL) < 0) {
51                 /* This is serious, but not fatal */
52                 printk(KERN_ERR "Voyager: Failed to create system monitor thread!!!\n");
53                 return 1;
54         }
55         return 0;
56 }
57
58 static int
59 execute(const char *string)
60 {
61         int ret;
62
63         char *envp[] = {
64                 "HOME=/",
65                 "TERM=linux",
66                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
67                 NULL,
68         };
69         char *argv[] = {
70                 "/bin/bash",
71                 "-c",
72                 (char *)string,
73                 NULL,
74         };
75
76         if ((ret = call_usermodehelper(argv[0], argv, envp, 1)) != 0) {
77                 printk(KERN_ERR "Voyager failed to run \"%s\": %i\n",
78                        string, ret);
79         }
80         return ret;
81 }
82
83 static void
84 check_from_kernel(void)
85 {
86         if(voyager_status.switch_off) {
87                 
88                 /* FIXME: This should be configureable via proc */
89                 execute("umask 600; echo 0 > /etc/initrunlvl; kill -HUP 1");
90         } else if(voyager_status.power_fail) {
91                 VDEBUG(("Voyager daemon detected AC power failure\n"));
92                 
93                 /* FIXME: This should be configureable via proc */
94                 execute("umask 600; echo F > /etc/powerstatus; kill -PWR 1");
95                 set_timeout = 1;
96         }
97 }
98
99 static void
100 check_continuing_condition(void)
101 {
102         if(voyager_status.power_fail) {
103                 __u8 data;
104                 voyager_cat_psi(VOYAGER_PSI_SUBREAD, 
105                                 VOYAGER_PSI_AC_FAIL_REG, &data);
106                 if((data & 0x1f) == 0) {
107                         /* all power restored */
108                         printk(KERN_NOTICE "VOYAGER AC power restored, cancelling shutdown\n");
109                         /* FIXME: should be user configureable */
110                         execute("umask 600; echo O > /etc/powerstatus; kill -PWR 1");
111                         set_timeout = 0;
112                 }
113         }
114 }
115
116 static void
117 wakeup(unsigned long unused)
118 {
119         up(&kvoyagerd_sem);
120 }
121
122 static int
123 thread(void *unused)
124 {
125         struct timer_list wakeup_timer;
126
127         kvoyagerd_running = 1;
128
129         reparent_to_init();
130         daemonize(THREAD_NAME);
131
132         set_timeout = 0;
133
134         init_timer(&wakeup_timer);
135
136         sigfillset(&current->blocked);
137         current->signal->tty = NULL;
138
139         printk(KERN_NOTICE "Voyager starting monitor thread\n");
140
141         for(;;) {
142                 down_interruptible(&kvoyagerd_sem);
143                 VDEBUG(("Voyager Daemon awoken\n"));
144                 if(voyager_status.request_from_kernel == 0) {
145                         /* probably awoken from timeout */
146                         check_continuing_condition();
147                 } else {
148                         check_from_kernel();
149                         voyager_status.request_from_kernel = 0;
150                 }
151                 if(set_timeout) {
152                         del_timer(&wakeup_timer);
153                         wakeup_timer.expires = HZ + jiffies;
154                         wakeup_timer.function = wakeup;
155                         add_timer(&wakeup_timer);
156                 }
157         }
158 }
159
160 static void __exit
161 voyager_thread_stop(void)
162 {
163         /* FIXME: do nothing at the moment */
164 }
165
166 module_init(voyager_thread_start);
167 //module_exit(voyager_thread_stop);