staging: lustre: acl: Remove lustre_posix_acl_xattr_free wrapper
[linux-2.6/btrfs-unstable.git] / drivers / watchdog / cpu5wdt.c
blob6d03e8e30f8bf4369cfaa6cecde6cb2a6dccb03c
1 /*
2 * sma cpu5 watchdog driver
4 * Copyright (C) 2003 Heiko Ronsdorf <hero@ihg.uni-duisburg.de>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 #include <linux/module.h>
25 #include <linux/moduleparam.h>
26 #include <linux/types.h>
27 #include <linux/errno.h>
28 #include <linux/miscdevice.h>
29 #include <linux/fs.h>
30 #include <linux/ioport.h>
31 #include <linux/timer.h>
32 #include <linux/completion.h>
33 #include <linux/jiffies.h>
34 #include <linux/io.h>
35 #include <linux/uaccess.h>
36 #include <linux/watchdog.h>
38 /* adjustable parameters */
40 static int verbose;
41 static int port = 0x91;
42 static int ticks = 10000;
43 static DEFINE_SPINLOCK(cpu5wdt_lock);
45 #define PFX "cpu5wdt: "
47 #define CPU5WDT_EXTENT 0x0A
49 #define CPU5WDT_STATUS_REG 0x00
50 #define CPU5WDT_TIME_A_REG 0x02
51 #define CPU5WDT_TIME_B_REG 0x03
52 #define CPU5WDT_MODE_REG 0x04
53 #define CPU5WDT_TRIGGER_REG 0x07
54 #define CPU5WDT_ENABLE_REG 0x08
55 #define CPU5WDT_RESET_REG 0x09
57 #define CPU5WDT_INTERVAL (HZ/10+1)
59 /* some device data */
61 static struct {
62 struct completion stop;
63 int running;
64 struct timer_list timer;
65 int queue;
66 int default_ticks;
67 unsigned long inuse;
68 } cpu5wdt_device;
70 /* generic helper functions */
72 static void cpu5wdt_trigger(unsigned long unused)
74 if (verbose > 2)
75 pr_debug("trigger at %i ticks\n", ticks);
77 if (cpu5wdt_device.running)
78 ticks--;
80 spin_lock(&cpu5wdt_lock);
81 /* keep watchdog alive */
82 outb(1, port + CPU5WDT_TRIGGER_REG);
84 /* requeue?? */
85 if (cpu5wdt_device.queue && ticks)
86 mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
87 else {
88 /* ticks doesn't matter anyway */
89 complete(&cpu5wdt_device.stop);
91 spin_unlock(&cpu5wdt_lock);
95 static void cpu5wdt_reset(void)
97 ticks = cpu5wdt_device.default_ticks;
99 if (verbose)
100 pr_debug("reset (%i ticks)\n", (int) ticks);
104 static void cpu5wdt_start(void)
106 unsigned long flags;
108 spin_lock_irqsave(&cpu5wdt_lock, flags);
109 if (!cpu5wdt_device.queue) {
110 cpu5wdt_device.queue = 1;
111 outb(0, port + CPU5WDT_TIME_A_REG);
112 outb(0, port + CPU5WDT_TIME_B_REG);
113 outb(1, port + CPU5WDT_MODE_REG);
114 outb(0, port + CPU5WDT_RESET_REG);
115 outb(0, port + CPU5WDT_ENABLE_REG);
116 mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
118 /* if process dies, counter is not decremented */
119 cpu5wdt_device.running++;
120 spin_unlock_irqrestore(&cpu5wdt_lock, flags);
123 static int cpu5wdt_stop(void)
125 unsigned long flags;
127 spin_lock_irqsave(&cpu5wdt_lock, flags);
128 if (cpu5wdt_device.running)
129 cpu5wdt_device.running = 0;
130 ticks = cpu5wdt_device.default_ticks;
131 spin_unlock_irqrestore(&cpu5wdt_lock, flags);
132 if (verbose)
133 pr_crit("stop not possible\n");
134 return -EIO;
137 /* filesystem operations */
139 static int cpu5wdt_open(struct inode *inode, struct file *file)
141 if (test_and_set_bit(0, &cpu5wdt_device.inuse))
142 return -EBUSY;
143 return nonseekable_open(inode, file);
146 static int cpu5wdt_release(struct inode *inode, struct file *file)
148 clear_bit(0, &cpu5wdt_device.inuse);
149 return 0;
152 static long cpu5wdt_ioctl(struct file *file, unsigned int cmd,
153 unsigned long arg)
155 void __user *argp = (void __user *)arg;
156 int __user *p = argp;
157 unsigned int value;
158 static const struct watchdog_info ident = {
159 .options = WDIOF_CARDRESET,
160 .identity = "CPU5 WDT",
163 switch (cmd) {
164 case WDIOC_GETSUPPORT:
165 if (copy_to_user(argp, &ident, sizeof(ident)))
166 return -EFAULT;
167 break;
168 case WDIOC_GETSTATUS:
169 value = inb(port + CPU5WDT_STATUS_REG);
170 value = (value >> 2) & 1;
171 return put_user(value, p);
172 case WDIOC_GETBOOTSTATUS:
173 return put_user(0, p);
174 case WDIOC_SETOPTIONS:
175 if (get_user(value, p))
176 return -EFAULT;
177 if (value & WDIOS_ENABLECARD)
178 cpu5wdt_start();
179 if (value & WDIOS_DISABLECARD)
180 cpu5wdt_stop();
181 break;
182 case WDIOC_KEEPALIVE:
183 cpu5wdt_reset();
184 break;
185 default:
186 return -ENOTTY;
188 return 0;
191 static ssize_t cpu5wdt_write(struct file *file, const char __user *buf,
192 size_t count, loff_t *ppos)
194 if (!count)
195 return -EIO;
196 cpu5wdt_reset();
197 return count;
200 static const struct file_operations cpu5wdt_fops = {
201 .owner = THIS_MODULE,
202 .llseek = no_llseek,
203 .unlocked_ioctl = cpu5wdt_ioctl,
204 .open = cpu5wdt_open,
205 .write = cpu5wdt_write,
206 .release = cpu5wdt_release,
209 static struct miscdevice cpu5wdt_misc = {
210 .minor = WATCHDOG_MINOR,
211 .name = "watchdog",
212 .fops = &cpu5wdt_fops,
215 /* init/exit function */
217 static int cpu5wdt_init(void)
219 unsigned int val;
220 int err;
222 if (verbose)
223 pr_debug("port=0x%x, verbose=%i\n", port, verbose);
225 init_completion(&cpu5wdt_device.stop);
226 cpu5wdt_device.queue = 0;
227 setup_timer(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);
228 cpu5wdt_device.default_ticks = ticks;
230 if (!request_region(port, CPU5WDT_EXTENT, PFX)) {
231 pr_err("request_region failed\n");
232 err = -EBUSY;
233 goto no_port;
236 /* watchdog reboot? */
237 val = inb(port + CPU5WDT_STATUS_REG);
238 val = (val >> 2) & 1;
239 if (!val)
240 pr_info("sorry, was my fault\n");
242 err = misc_register(&cpu5wdt_misc);
243 if (err < 0) {
244 pr_err("misc_register failed\n");
245 goto no_misc;
249 pr_info("init success\n");
250 return 0;
252 no_misc:
253 release_region(port, CPU5WDT_EXTENT);
254 no_port:
255 return err;
258 static int cpu5wdt_init_module(void)
260 return cpu5wdt_init();
263 static void cpu5wdt_exit(void)
265 if (cpu5wdt_device.queue) {
266 cpu5wdt_device.queue = 0;
267 wait_for_completion(&cpu5wdt_device.stop);
268 del_timer(&cpu5wdt_device.timer);
271 misc_deregister(&cpu5wdt_misc);
273 release_region(port, CPU5WDT_EXTENT);
277 static void cpu5wdt_exit_module(void)
279 cpu5wdt_exit();
282 /* module entry points */
284 module_init(cpu5wdt_init_module);
285 module_exit(cpu5wdt_exit_module);
287 MODULE_AUTHOR("Heiko Ronsdorf <hero@ihg.uni-duisburg.de>");
288 MODULE_DESCRIPTION("sma cpu5 watchdog driver");
289 MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog");
290 MODULE_LICENSE("GPL");
292 module_param(port, int, 0);
293 MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");
295 module_param(verbose, int, 0);
296 MODULE_PARM_DESC(verbose, "be verbose, default is 0 (no)");
298 module_param(ticks, int, 0);
299 MODULE_PARM_DESC(ticks, "count down ticks, default is 10000");