gpio: palmas: fix compilation failures
[linux-2.6.git] / drivers / watchdog / w83697ug_wdt.c
1 /*
2  *      w83697ug/uf WDT driver
3  *
4  *      (c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
5  *              reused original code to support w83697ug/uf.
6  *
7  *      Based on w83627hf_wdt.c which is based on advantechwdt.c
8  *      which is based on wdt.c.
9  *      Original copyright messages:
10  *
11  *      (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
12  *              added support for W83627THF.
13  *
14  *      (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
15  *
16  *      (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
17  *
18  *      (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
19  *                              http://www.redhat.com
20  *
21  *      This program is free software; you can redistribute it and/or
22  *      modify it under the terms of the GNU General Public License
23  *      as published by the Free Software Foundation; either version
24  *      2 of the License, or (at your option) any later version.
25  *
26  *      Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
27  *      warranty for any of this software. This material is provided
28  *      "AS-IS" and at no charge.
29  *
30  *      (c) Copyright 1995    Alan Cox <alan@redhat.com>
31  */
32
33 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 #include <linux/types.h>
38 #include <linux/miscdevice.h>
39 #include <linux/watchdog.h>
40 #include <linux/fs.h>
41 #include <linux/ioport.h>
42 #include <linux/notifier.h>
43 #include <linux/reboot.h>
44 #include <linux/init.h>
45 #include <linux/spinlock.h>
46 #include <linux/io.h>
47 #include <linux/uaccess.h>
48
49
50 #define WATCHDOG_NAME "w83697ug/uf WDT"
51 #define WATCHDOG_TIMEOUT 60             /* 60 sec default timeout */
52
53 static unsigned long wdt_is_open;
54 static char expect_close;
55 static DEFINE_SPINLOCK(io_lock);
56
57 static int wdt_io = 0x2e;
58 module_param(wdt_io, int, 0);
59 MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");
60
61 static int timeout = WATCHDOG_TIMEOUT;  /* in seconds */
62 module_param(timeout, int, 0);
63 MODULE_PARM_DESC(timeout,
64         "Watchdog timeout in seconds. 1<= timeout <=255 (default="
65                                 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
66
67 static bool nowayout = WATCHDOG_NOWAYOUT;
68 module_param(nowayout, bool, 0);
69 MODULE_PARM_DESC(nowayout,
70         "Watchdog cannot be stopped once started (default="
71                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
72
73 /*
74  *      Kernel methods.
75  */
76
77 #define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
78 #define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
79                                                         (same as EFER) */
80 #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
81
82 static int w83697ug_select_wd_register(void)
83 {
84         unsigned char c;
85         unsigned char version;
86
87         outb_p(0x87, WDT_EFER); /* Enter extended function mode */
88         outb_p(0x87, WDT_EFER); /* Again according to manual */
89
90         outb(0x20, WDT_EFER);   /* check chip version   */
91         version = inb(WDT_EFDR);
92
93         if (version == 0x68) {  /* W83697UG             */
94                 pr_info("Watchdog chip version 0x%02x = W83697UG/UF found at 0x%04x\n",
95                         version, wdt_io);
96
97                 outb_p(0x2b, WDT_EFER);
98                 c = inb_p(WDT_EFDR);    /* select WDT0 */
99                 c &= ~0x04;
100                 outb_p(0x2b, WDT_EFER);
101                 outb_p(c, WDT_EFDR);    /* set pin118 to WDT0 */
102
103         } else {
104                 pr_err("No W83697UG/UF could be found\n");
105                 return -ENODEV;
106         }
107
108         outb_p(0x07, WDT_EFER); /* point to logical device number reg */
109         outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
110         outb_p(0x30, WDT_EFER); /* select CR30 */
111         c = inb_p(WDT_EFDR);
112         outb_p(c | 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */
113
114         return 0;
115 }
116
117 static void w83697ug_unselect_wd_register(void)
118 {
119         outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
120 }
121
122 static int w83697ug_init(void)
123 {
124         int ret;
125         unsigned char t;
126
127         ret = w83697ug_select_wd_register();
128         if (ret != 0)
129                 return ret;
130
131         outb_p(0xF6, WDT_EFER); /* Select CRF6 */
132         t = inb_p(WDT_EFDR);    /* read CRF6 */
133         if (t != 0) {
134                 pr_info("Watchdog already running. Resetting timeout to %d sec\n",
135                         timeout);
136                 outb_p(timeout, WDT_EFDR);    /* Write back to CRF6 */
137         }
138         outb_p(0xF5, WDT_EFER); /* Select CRF5 */
139         t = inb_p(WDT_EFDR);    /* read CRF5 */
140         t &= ~0x0C;             /* set second mode &
141                                         disable keyboard turning off watchdog */
142         outb_p(t, WDT_EFDR);    /* Write back to CRF5 */
143
144         w83697ug_unselect_wd_register();
145         return 0;
146 }
147
148 static void wdt_ctrl(int timeout)
149 {
150         spin_lock(&io_lock);
151
152         if (w83697ug_select_wd_register() < 0) {
153                 spin_unlock(&io_lock);
154                 return;
155         }
156
157         outb_p(0xF4, WDT_EFER);    /* Select CRF4 */
158         outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */
159
160         w83697ug_unselect_wd_register();
161
162         spin_unlock(&io_lock);
163 }
164
165 static int wdt_ping(void)
166 {
167         wdt_ctrl(timeout);
168         return 0;
169 }
170
171 static int wdt_disable(void)
172 {
173         wdt_ctrl(0);
174         return 0;
175 }
176
177 static int wdt_set_heartbeat(int t)
178 {
179         if (t < 1 || t > 255)
180                 return -EINVAL;
181
182         timeout = t;
183         return 0;
184 }
185
186 static ssize_t wdt_write(struct file *file, const char __user *buf,
187                                                 size_t count, loff_t *ppos)
188 {
189         if (count) {
190                 if (!nowayout) {
191                         size_t i;
192
193                         expect_close = 0;
194
195                         for (i = 0; i != count; i++) {
196                                 char c;
197                                 if (get_user(c, buf + i))
198                                         return -EFAULT;
199                                 if (c == 'V')
200                                         expect_close = 42;
201                         }
202                 }
203                 wdt_ping();
204         }
205         return count;
206 }
207
208 static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
209 {
210         void __user *argp = (void __user *)arg;
211         int __user *p = argp;
212         int new_timeout;
213         static const struct watchdog_info ident = {
214                 .options =              WDIOF_KEEPALIVEPING |
215                                         WDIOF_SETTIMEOUT |
216                                         WDIOF_MAGICCLOSE,
217                 .firmware_version =     1,
218                 .identity =             "W83697UG WDT",
219         };
220
221         switch (cmd) {
222         case WDIOC_GETSUPPORT:
223                 if (copy_to_user(argp, &ident, sizeof(ident)))
224                         return -EFAULT;
225                 break;
226
227         case WDIOC_GETSTATUS:
228         case WDIOC_GETBOOTSTATUS:
229                 return put_user(0, p);
230
231         case WDIOC_SETOPTIONS:
232         {
233                 int options, retval = -EINVAL;
234
235                 if (get_user(options, p))
236                         return -EFAULT;
237
238                 if (options & WDIOS_DISABLECARD) {
239                         wdt_disable();
240                         retval = 0;
241                 }
242
243                 if (options & WDIOS_ENABLECARD) {
244                         wdt_ping();
245                         retval = 0;
246                 }
247
248                 return retval;
249         }
250
251         case WDIOC_KEEPALIVE:
252                 wdt_ping();
253                 break;
254
255         case WDIOC_SETTIMEOUT:
256                 if (get_user(new_timeout, p))
257                         return -EFAULT;
258                 if (wdt_set_heartbeat(new_timeout))
259                         return -EINVAL;
260                 wdt_ping();
261                 /* Fall */
262
263         case WDIOC_GETTIMEOUT:
264                 return put_user(timeout, p);
265
266         default:
267                 return -ENOTTY;
268         }
269         return 0;
270 }
271
272 static int wdt_open(struct inode *inode, struct file *file)
273 {
274         if (test_and_set_bit(0, &wdt_is_open))
275                 return -EBUSY;
276         /*
277          *      Activate
278          */
279
280         wdt_ping();
281         return nonseekable_open(inode, file);
282 }
283
284 static int wdt_close(struct inode *inode, struct file *file)
285 {
286         if (expect_close == 42)
287                 wdt_disable();
288         else {
289                 pr_crit("Unexpected close, not stopping watchdog!\n");
290                 wdt_ping();
291         }
292         expect_close = 0;
293         clear_bit(0, &wdt_is_open);
294         return 0;
295 }
296
297 /*
298  *      Notifier for system down
299  */
300
301 static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
302         void *unused)
303 {
304         if (code == SYS_DOWN || code == SYS_HALT)
305                 wdt_disable();  /* Turn the WDT off */
306
307         return NOTIFY_DONE;
308 }
309
310 /*
311  *      Kernel Interfaces
312  */
313
314 static const struct file_operations wdt_fops = {
315         .owner          = THIS_MODULE,
316         .llseek         = no_llseek,
317         .write          = wdt_write,
318         .unlocked_ioctl = wdt_ioctl,
319         .open           = wdt_open,
320         .release        = wdt_close,
321 };
322
323 static struct miscdevice wdt_miscdev = {
324         .minor = WATCHDOG_MINOR,
325         .name = "watchdog",
326         .fops = &wdt_fops,
327 };
328
329 /*
330  *      The WDT needs to learn about soft shutdowns in order to
331  *      turn the timebomb registers off.
332  */
333
334 static struct notifier_block wdt_notifier = {
335         .notifier_call = wdt_notify_sys,
336 };
337
338 static int __init wdt_init(void)
339 {
340         int ret;
341
342         pr_info("WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising\n");
343
344         if (wdt_set_heartbeat(timeout)) {
345                 wdt_set_heartbeat(WATCHDOG_TIMEOUT);
346                 pr_info("timeout value must be 1<=timeout<=255, using %d\n",
347                         WATCHDOG_TIMEOUT);
348         }
349
350         if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
351                 pr_err("I/O address 0x%04x already in use\n", wdt_io);
352                 ret = -EIO;
353                 goto out;
354         }
355
356         ret = w83697ug_init();
357         if (ret != 0)
358                 goto unreg_regions;
359
360         ret = register_reboot_notifier(&wdt_notifier);
361         if (ret != 0) {
362                 pr_err("cannot register reboot notifier (err=%d)\n", ret);
363                 goto unreg_regions;
364         }
365
366         ret = misc_register(&wdt_miscdev);
367         if (ret != 0) {
368                 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
369                        WATCHDOG_MINOR, ret);
370                 goto unreg_reboot;
371         }
372
373         pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
374                 timeout, nowayout);
375
376 out:
377         return ret;
378 unreg_reboot:
379         unregister_reboot_notifier(&wdt_notifier);
380 unreg_regions:
381         release_region(wdt_io, 1);
382         goto out;
383 }
384
385 static void __exit wdt_exit(void)
386 {
387         misc_deregister(&wdt_miscdev);
388         unregister_reboot_notifier(&wdt_notifier);
389         release_region(wdt_io, 1);
390 }
391
392 module_init(wdt_init);
393 module_exit(wdt_exit);
394
395 MODULE_LICENSE("GPL");
396 MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
397 MODULE_DESCRIPTION("w83697ug/uf WDT driver");
398 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);