diff options
author | Wim Van Sebroeck <wim@iguana.be> | 2007-08-17 04:38:02 -0400 |
---|---|---|
committer | Wim Van Sebroeck <wim@iguana.be> | 2007-10-18 06:39:03 -0400 |
commit | b7e04f8c61a46d742de23af5d7ca2b41b33e40ac (patch) | |
tree | c52a7ea568648e2d8ed0d423098b42298de2058b /drivers/watchdog/alim7101_wdt.c | |
parent | d85714d81cc0408daddb68c10f7fd69eafe7c213 (diff) |
mv watchdog tree under drivers
move watchdog tree from drivers/char/watchdog to drivers/watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/alim7101_wdt.c')
-rw-r--r-- | drivers/watchdog/alim7101_wdt.c | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/drivers/watchdog/alim7101_wdt.c b/drivers/watchdog/alim7101_wdt.c new file mode 100644 index 000000000000..67aed9f8c362 --- /dev/null +++ b/drivers/watchdog/alim7101_wdt.c | |||
@@ -0,0 +1,423 @@ | |||
1 | /* | ||
2 | * ALi M7101 PMU Computer Watchdog Timer driver | ||
3 | * | ||
4 | * Based on w83877f_wdt.c by Scott Jennings <linuxdrivers@oro.net> | ||
5 | * and the Cobalt kernel WDT timer driver by Tim Hockin | ||
6 | * <thockin@cobaltnet.com> | ||
7 | * | ||
8 | * (c)2002 Steve Hill <steve@navaho.co.uk> | ||
9 | * | ||
10 | * This WDT driver is different from most other Linux WDT | ||
11 | * drivers in that the driver will ping the watchdog by itself, | ||
12 | * because this particular WDT has a very short timeout (1.6 | ||
13 | * seconds) and it would be insane to count on any userspace | ||
14 | * daemon always getting scheduled within that time frame. | ||
15 | * | ||
16 | * Additions: | ||
17 | * Aug 23, 2004 - Added use_gpio module parameter for use on revision a1d PMUs | ||
18 | * found on very old cobalt hardware. | ||
19 | * -- Mike Waychison <michael.waychison@sun.com> | ||
20 | */ | ||
21 | |||
22 | #include <linux/module.h> | ||
23 | #include <linux/moduleparam.h> | ||
24 | #include <linux/types.h> | ||
25 | #include <linux/timer.h> | ||
26 | #include <linux/miscdevice.h> | ||
27 | #include <linux/watchdog.h> | ||
28 | #include <linux/ioport.h> | ||
29 | #include <linux/notifier.h> | ||
30 | #include <linux/reboot.h> | ||
31 | #include <linux/init.h> | ||
32 | #include <linux/fs.h> | ||
33 | #include <linux/pci.h> | ||
34 | |||
35 | #include <asm/io.h> | ||
36 | #include <asm/uaccess.h> | ||
37 | #include <asm/system.h> | ||
38 | |||
39 | #define OUR_NAME "alim7101_wdt" | ||
40 | #define PFX OUR_NAME ": " | ||
41 | |||
42 | #define WDT_ENABLE 0x9C | ||
43 | #define WDT_DISABLE 0x8C | ||
44 | |||
45 | #define ALI_7101_WDT 0x92 | ||
46 | #define ALI_7101_GPIO 0x7D | ||
47 | #define ALI_7101_GPIO_O 0x7E | ||
48 | #define ALI_WDT_ARM 0x01 | ||
49 | |||
50 | /* | ||
51 | * We're going to use a 1 second timeout. | ||
52 | * If we reset the watchdog every ~250ms we should be safe. */ | ||
53 | |||
54 | #define WDT_INTERVAL (HZ/4+1) | ||
55 | |||
56 | /* | ||
57 | * We must not require too good response from the userspace daemon. | ||
58 | * Here we require the userspace daemon to send us a heartbeat | ||
59 | * char to /dev/watchdog every 30 seconds. | ||
60 | */ | ||
61 | |||
62 | #define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */ | ||
63 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */ | ||
64 | module_param(timeout, int, 0); | ||
65 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); | ||
66 | |||
67 | static int use_gpio = 0; /* Use the pic (for a1d revision alim7101) */ | ||
68 | module_param(use_gpio, int, 0); | ||
69 | MODULE_PARM_DESC(use_gpio, "Use the gpio watchdog. (required by old cobalt boards)"); | ||
70 | |||
71 | static void wdt_timer_ping(unsigned long); | ||
72 | static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1); | ||
73 | static unsigned long next_heartbeat; | ||
74 | static unsigned long wdt_is_open; | ||
75 | static char wdt_expect_close; | ||
76 | static struct pci_dev *alim7101_pmu; | ||
77 | |||
78 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
79 | module_param(nowayout, int, 0); | ||
80 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" | ||
81 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
82 | |||
83 | /* | ||
84 | * Whack the dog | ||
85 | */ | ||
86 | |||
87 | static void wdt_timer_ping(unsigned long data) | ||
88 | { | ||
89 | /* If we got a heartbeat pulse within the WDT_US_INTERVAL | ||
90 | * we agree to ping the WDT | ||
91 | */ | ||
92 | char tmp; | ||
93 | |||
94 | if(time_before(jiffies, next_heartbeat)) | ||
95 | { | ||
96 | /* Ping the WDT (this is actually a disarm/arm sequence) */ | ||
97 | pci_read_config_byte(alim7101_pmu, 0x92, &tmp); | ||
98 | pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM)); | ||
99 | pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM)); | ||
100 | if (use_gpio) { | ||
101 | pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp); | ||
102 | pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp | ||
103 | | 0x20); | ||
104 | pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp | ||
105 | & ~0x20); | ||
106 | } | ||
107 | } else { | ||
108 | printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n"); | ||
109 | } | ||
110 | /* Re-set the timer interval */ | ||
111 | mod_timer(&timer, jiffies + WDT_INTERVAL); | ||
112 | } | ||
113 | |||
114 | /* | ||
115 | * Utility routines | ||
116 | */ | ||
117 | |||
118 | static void wdt_change(int writeval) | ||
119 | { | ||
120 | char tmp; | ||
121 | |||
122 | pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp); | ||
123 | if (writeval == WDT_ENABLE) { | ||
124 | pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM)); | ||
125 | if (use_gpio) { | ||
126 | pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp); | ||
127 | pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp & ~0x20); | ||
128 | } | ||
129 | |||
130 | } else { | ||
131 | pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM)); | ||
132 | if (use_gpio) { | ||
133 | pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp); | ||
134 | pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp | 0x20); | ||
135 | } | ||
136 | } | ||
137 | } | ||
138 | |||
139 | static void wdt_startup(void) | ||
140 | { | ||
141 | next_heartbeat = jiffies + (timeout * HZ); | ||
142 | |||
143 | /* We must enable before we kick off the timer in case the timer | ||
144 | occurs as we ping it */ | ||
145 | |||
146 | wdt_change(WDT_ENABLE); | ||
147 | |||
148 | /* Start the timer */ | ||
149 | mod_timer(&timer, jiffies + WDT_INTERVAL); | ||
150 | |||
151 | printk(KERN_INFO PFX "Watchdog timer is now enabled.\n"); | ||
152 | } | ||
153 | |||
154 | static void wdt_turnoff(void) | ||
155 | { | ||
156 | /* Stop the timer */ | ||
157 | del_timer_sync(&timer); | ||
158 | wdt_change(WDT_DISABLE); | ||
159 | printk(KERN_INFO PFX "Watchdog timer is now disabled...\n"); | ||
160 | } | ||
161 | |||
162 | static void wdt_keepalive(void) | ||
163 | { | ||
164 | /* user land ping */ | ||
165 | next_heartbeat = jiffies + (timeout * HZ); | ||
166 | } | ||
167 | |||
168 | /* | ||
169 | * /dev/watchdog handling | ||
170 | */ | ||
171 | |||
172 | static ssize_t fop_write(struct file * file, const char __user * buf, size_t count, loff_t * ppos) | ||
173 | { | ||
174 | /* See if we got the magic character 'V' and reload the timer */ | ||
175 | if(count) { | ||
176 | if (!nowayout) { | ||
177 | size_t ofs; | ||
178 | |||
179 | /* note: just in case someone wrote the magic character | ||
180 | * five months ago... */ | ||
181 | wdt_expect_close = 0; | ||
182 | |||
183 | /* now scan */ | ||
184 | for (ofs = 0; ofs != count; ofs++) { | ||
185 | char c; | ||
186 | if (get_user(c, buf+ofs)) | ||
187 | return -EFAULT; | ||
188 | if (c == 'V') | ||
189 | wdt_expect_close = 42; | ||
190 | } | ||
191 | } | ||
192 | /* someone wrote to us, we should restart timer */ | ||
193 | wdt_keepalive(); | ||
194 | } | ||
195 | return count; | ||
196 | } | ||
197 | |||
198 | static int fop_open(struct inode * inode, struct file * file) | ||
199 | { | ||
200 | /* Just in case we're already talking to someone... */ | ||
201 | if(test_and_set_bit(0, &wdt_is_open)) | ||
202 | return -EBUSY; | ||
203 | /* Good, fire up the show */ | ||
204 | wdt_startup(); | ||
205 | return nonseekable_open(inode, file); | ||
206 | } | ||
207 | |||
208 | static int fop_close(struct inode * inode, struct file * file) | ||
209 | { | ||
210 | if(wdt_expect_close == 42) | ||
211 | wdt_turnoff(); | ||
212 | else { | ||
213 | /* wim: shouldn't there be a: del_timer(&timer); */ | ||
214 | printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n"); | ||
215 | } | ||
216 | clear_bit(0, &wdt_is_open); | ||
217 | wdt_expect_close = 0; | ||
218 | return 0; | ||
219 | } | ||
220 | |||
221 | static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) | ||
222 | { | ||
223 | void __user *argp = (void __user *)arg; | ||
224 | int __user *p = argp; | ||
225 | static struct watchdog_info ident = | ||
226 | { | ||
227 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, | ||
228 | .firmware_version = 1, | ||
229 | .identity = "ALiM7101", | ||
230 | }; | ||
231 | |||
232 | switch(cmd) | ||
233 | { | ||
234 | case WDIOC_GETSUPPORT: | ||
235 | return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0; | ||
236 | case WDIOC_GETSTATUS: | ||
237 | case WDIOC_GETBOOTSTATUS: | ||
238 | return put_user(0, p); | ||
239 | case WDIOC_KEEPALIVE: | ||
240 | wdt_keepalive(); | ||
241 | return 0; | ||
242 | case WDIOC_SETOPTIONS: | ||
243 | { | ||
244 | int new_options, retval = -EINVAL; | ||
245 | |||
246 | if(get_user(new_options, p)) | ||
247 | return -EFAULT; | ||
248 | |||
249 | if(new_options & WDIOS_DISABLECARD) { | ||
250 | wdt_turnoff(); | ||
251 | retval = 0; | ||
252 | } | ||
253 | |||
254 | if(new_options & WDIOS_ENABLECARD) { | ||
255 | wdt_startup(); | ||
256 | retval = 0; | ||
257 | } | ||
258 | |||
259 | return retval; | ||
260 | } | ||
261 | case WDIOC_SETTIMEOUT: | ||
262 | { | ||
263 | int new_timeout; | ||
264 | |||
265 | if(get_user(new_timeout, p)) | ||
266 | return -EFAULT; | ||
267 | |||
268 | if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */ | ||
269 | return -EINVAL; | ||
270 | |||
271 | timeout = new_timeout; | ||
272 | wdt_keepalive(); | ||
273 | /* Fall through */ | ||
274 | } | ||
275 | case WDIOC_GETTIMEOUT: | ||
276 | return put_user(timeout, p); | ||
277 | default: | ||
278 | return -ENOTTY; | ||
279 | } | ||
280 | } | ||
281 | |||
282 | static const struct file_operations wdt_fops = { | ||
283 | .owner= THIS_MODULE, | ||
284 | .llseek= no_llseek, | ||
285 | .write= fop_write, | ||
286 | .open= fop_open, | ||
287 | .release= fop_close, | ||
288 | .ioctl= fop_ioctl, | ||
289 | }; | ||
290 | |||
291 | static struct miscdevice wdt_miscdev = { | ||
292 | .minor=WATCHDOG_MINOR, | ||
293 | .name="watchdog", | ||
294 | .fops=&wdt_fops, | ||
295 | }; | ||
296 | |||
297 | /* | ||
298 | * Notifier for system down | ||
299 | */ | ||
300 | |||
301 | static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused) | ||
302 | { | ||
303 | if (code==SYS_DOWN || code==SYS_HALT) | ||
304 | wdt_turnoff(); | ||
305 | |||
306 | if (code==SYS_RESTART) { | ||
307 | /* | ||
308 | * Cobalt devices have no way of rebooting themselves other than | ||
309 | * getting the watchdog to pull reset, so we restart the watchdog on | ||
310 | * reboot with no heartbeat | ||
311 | */ | ||
312 | wdt_change(WDT_ENABLE); | ||
313 | printk(KERN_INFO PFX "Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second.\n"); | ||
314 | } | ||
315 | return NOTIFY_DONE; | ||
316 | } | ||
317 | |||
318 | /* | ||
319 | * The WDT needs to learn about soft shutdowns in order to | ||
320 | * turn the timebomb registers off. | ||
321 | */ | ||
322 | |||
323 | static struct notifier_block wdt_notifier= | ||
324 | { | ||
325 | .notifier_call = wdt_notify_sys, | ||
326 | }; | ||
327 | |||
328 | static void __exit alim7101_wdt_unload(void) | ||
329 | { | ||
330 | wdt_turnoff(); | ||
331 | /* Deregister */ | ||
332 | misc_deregister(&wdt_miscdev); | ||
333 | unregister_reboot_notifier(&wdt_notifier); | ||
334 | pci_dev_put(alim7101_pmu); | ||
335 | } | ||
336 | |||
337 | static int __init alim7101_wdt_init(void) | ||
338 | { | ||
339 | int rc = -EBUSY; | ||
340 | struct pci_dev *ali1543_south; | ||
341 | char tmp; | ||
342 | |||
343 | printk(KERN_INFO PFX "Steve Hill <steve@navaho.co.uk>.\n"); | ||
344 | alim7101_pmu = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101, | ||
345 | NULL); | ||
346 | if (!alim7101_pmu) { | ||
347 | printk(KERN_INFO PFX "ALi M7101 PMU not present - WDT not set\n"); | ||
348 | return -EBUSY; | ||
349 | } | ||
350 | |||
351 | /* Set the WDT in the PMU to 1 second */ | ||
352 | pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, 0x02); | ||
353 | |||
354 | ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, | ||
355 | NULL); | ||
356 | if (!ali1543_south) { | ||
357 | printk(KERN_INFO PFX "ALi 1543 South-Bridge not present - WDT not set\n"); | ||
358 | goto err_out; | ||
359 | } | ||
360 | pci_read_config_byte(ali1543_south, 0x5e, &tmp); | ||
361 | pci_dev_put(ali1543_south); | ||
362 | if ((tmp & 0x1e) == 0x00) { | ||
363 | if (!use_gpio) { | ||
364 | printk(KERN_INFO PFX "Detected old alim7101 revision 'a1d'. If this is a cobalt board, set the 'use_gpio' module parameter.\n"); | ||
365 | goto err_out; | ||
366 | } | ||
367 | nowayout = 1; | ||
368 | } else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) { | ||
369 | printk(KERN_INFO PFX "ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n"); | ||
370 | goto err_out; | ||
371 | } | ||
372 | |||
373 | if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */ | ||
374 | { | ||
375 | timeout = WATCHDOG_TIMEOUT; | ||
376 | printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n", | ||
377 | timeout); | ||
378 | } | ||
379 | |||
380 | rc = misc_register(&wdt_miscdev); | ||
381 | if (rc) { | ||
382 | printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
383 | wdt_miscdev.minor, rc); | ||
384 | goto err_out; | ||
385 | } | ||
386 | |||
387 | rc = register_reboot_notifier(&wdt_notifier); | ||
388 | if (rc) { | ||
389 | printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
390 | rc); | ||
391 | goto err_out_miscdev; | ||
392 | } | ||
393 | |||
394 | if (nowayout) { | ||
395 | __module_get(THIS_MODULE); | ||
396 | } | ||
397 | |||
398 | printk(KERN_INFO PFX "WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n", | ||
399 | timeout, nowayout); | ||
400 | return 0; | ||
401 | |||
402 | err_out_miscdev: | ||
403 | misc_deregister(&wdt_miscdev); | ||
404 | err_out: | ||
405 | pci_dev_put(alim7101_pmu); | ||
406 | return rc; | ||
407 | } | ||
408 | |||
409 | module_init(alim7101_wdt_init); | ||
410 | module_exit(alim7101_wdt_unload); | ||
411 | |||
412 | static struct pci_device_id alim7101_pci_tbl[] __devinitdata = { | ||
413 | { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533) }, | ||
414 | { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, | ||
415 | { } | ||
416 | }; | ||
417 | |||
418 | MODULE_DEVICE_TABLE(pci, alim7101_pci_tbl); | ||
419 | |||
420 | MODULE_AUTHOR("Steve Hill"); | ||
421 | MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver"); | ||
422 | MODULE_LICENSE("GPL"); | ||
423 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||