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1/*
2 * Watchdog for the 7101 PMU version found in the ALi M1535 chipsets
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
9
10#include <linux/module.h>
11#include <linux/moduleparam.h>
12#include <linux/types.h>
13#include <linux/miscdevice.h>
14#include <linux/watchdog.h>
15#include <linux/ioport.h>
16#include <linux/notifier.h>
17#include <linux/reboot.h>
18#include <linux/init.h>
19#include <linux/fs.h>
20#include <linux/pci.h>
21#include <linux/uaccess.h>
22#include <linux/io.h>
23
24#define WATCHDOG_NAME "ALi_M1535"
25#define PFX WATCHDOG_NAME ": "
26#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
27
28/* internal variables */
29static unsigned long ali_is_open;
30static char ali_expect_release;
31static struct pci_dev *ali_pci;
32static u32 ali_timeout_bits; /* stores the computed timeout */
33static DEFINE_SPINLOCK(ali_lock); /* Guards the hardware */
34
35/* module parameters */
36static int timeout = WATCHDOG_TIMEOUT;
37module_param(timeout, int, 0);
38MODULE_PARM_DESC(timeout,
39 "Watchdog timeout in seconds. (0 < timeout < 18000, default="
40 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
41
42static int nowayout = WATCHDOG_NOWAYOUT;
43module_param(nowayout, int, 0);
44MODULE_PARM_DESC(nowayout,
45 "Watchdog cannot be stopped once started (default="
46 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
47
48/*
49 * ali_start - start watchdog countdown
50 *
51 * Starts the timer running providing the timer has a counter
52 * configuration set.
53 */
54
55static void ali_start(void)
56{
57 u32 val;
58
59 spin_lock(&ali_lock);
60
61 pci_read_config_dword(ali_pci, 0xCC, &val);
62 val &= ~0x3F; /* Mask count */
63 val |= (1 << 25) | ali_timeout_bits;
64 pci_write_config_dword(ali_pci, 0xCC, val);
65
66 spin_unlock(&ali_lock);
67}
68
69/*
70 * ali_stop - stop the timer countdown
71 *
72 * Stop the ALi watchdog countdown
73 */
74
75static void ali_stop(void)
76{
77 u32 val;
78
79 spin_lock(&ali_lock);
80
81 pci_read_config_dword(ali_pci, 0xCC, &val);
82 val &= ~0x3F; /* Mask count to zero (disabled) */
83 val &= ~(1 << 25); /* and for safety mask the reset enable */
84 pci_write_config_dword(ali_pci, 0xCC, val);
85
86 spin_unlock(&ali_lock);
87}
88
89/*
90 * ali_keepalive - send a keepalive to the watchdog
91 *
92 * Send a keepalive to the timer (actually we restart the timer).
93 */
94
95static void ali_keepalive(void)
96{
97 ali_start();
98}
99
100/*
101 * ali_settimer - compute the timer reload value
102 * @t: time in seconds
103 *
104 * Computes the timeout values needed
105 */
106
107static int ali_settimer(int t)
108{
109 if (t < 0)
110 return -EINVAL;
111 else if (t < 60)
112 ali_timeout_bits = t|(1 << 6);
113 else if (t < 3600)
114 ali_timeout_bits = (t / 60)|(1 << 7);
115 else if (t < 18000)
116 ali_timeout_bits = (t / 300)|(1 << 6)|(1 << 7);
117 else
118 return -EINVAL;
119
120 timeout = t;
121 return 0;
122}
123
124/*
125 * /dev/watchdog handling
126 */
127
128/*
129 * ali_write - writes to ALi watchdog
130 * @file: file from VFS
131 * @data: user address of data
132 * @len: length of data
133 * @ppos: pointer to the file offset
134 *
135 * Handle a write to the ALi watchdog. Writing to the file pings
136 * the watchdog and resets it. Writing the magic 'V' sequence allows
137 * the next close to turn off the watchdog.
138 */
139
140static ssize_t ali_write(struct file *file, const char __user *data,
141 size_t len, loff_t *ppos)
142{
143 /* See if we got the magic character 'V' and reload the timer */
144 if (len) {
145 if (!nowayout) {
146 size_t i;
147
148 /* note: just in case someone wrote the
149 magic character five months ago... */
150 ali_expect_release = 0;
151
152 /* scan to see whether or not we got
153 the magic character */
154 for (i = 0; i != len; i++) {
155 char c;
156 if (get_user(c, data + i))
157 return -EFAULT;
158 if (c == 'V')
159 ali_expect_release = 42;
160 }
161 }
162
163 /* someone wrote to us, we should reload the timer */
164 ali_start();
165 }
166 return len;
167}
168
169/*
170 * ali_ioctl - handle watchdog ioctls
171 * @file: VFS file pointer
172 * @cmd: ioctl number
173 * @arg: arguments to the ioctl
174 *
175 * Handle the watchdog ioctls supported by the ALi driver. Really
176 * we want an extension to enable irq ack monitoring and the like
177 */
178
179static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
180{
181 void __user *argp = (void __user *)arg;
182 int __user *p = argp;
183 static const struct watchdog_info ident = {
184 .options = WDIOF_KEEPALIVEPING |
185 WDIOF_SETTIMEOUT |
186 WDIOF_MAGICCLOSE,
187 .firmware_version = 0,
188 .identity = "ALi M1535 WatchDog Timer",
189 };
190
191 switch (cmd) {
192 case WDIOC_GETSUPPORT:
193 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
194
195 case WDIOC_GETSTATUS:
196 case WDIOC_GETBOOTSTATUS:
197 return put_user(0, p);
198 case WDIOC_SETOPTIONS:
199 {
200 int new_options, retval = -EINVAL;
201
202 if (get_user(new_options, p))
203 return -EFAULT;
204 if (new_options & WDIOS_DISABLECARD) {
205 ali_stop();
206 retval = 0;
207 }
208 if (new_options & WDIOS_ENABLECARD) {
209 ali_start();
210 retval = 0;
211 }
212 return retval;
213 }
214 case WDIOC_KEEPALIVE:
215 ali_keepalive();
216 return 0;
217 case WDIOC_SETTIMEOUT:
218 {
219 int new_timeout;
220 if (get_user(new_timeout, p))
221 return -EFAULT;
222 if (ali_settimer(new_timeout))
223 return -EINVAL;
224 ali_keepalive();
225 /* Fall */
226 }
227 case WDIOC_GETTIMEOUT:
228 return put_user(timeout, p);
229 default:
230 return -ENOTTY;
231 }
232}
233
234/*
235 * ali_open - handle open of ali watchdog
236 * @inode: inode from VFS
237 * @file: file from VFS
238 *
239 * Open the ALi watchdog device. Ensure only one person opens it
240 * at a time. Also start the watchdog running.
241 */
242
243static int ali_open(struct inode *inode, struct file *file)
244{
245 /* /dev/watchdog can only be opened once */
246 if (test_and_set_bit(0, &ali_is_open))
247 return -EBUSY;
248
249 /* Activate */
250 ali_start();
251 return nonseekable_open(inode, file);
252}
253
254/*
255 * ali_release - close an ALi watchdog
256 * @inode: inode from VFS
257 * @file: file from VFS
258 *
259 * Close the ALi watchdog device. Actual shutdown of the timer
260 * only occurs if the magic sequence has been set.
261 */
262
263static int ali_release(struct inode *inode, struct file *file)
264{
265 /*
266 * Shut off the timer.
267 */
268 if (ali_expect_release == 42)
269 ali_stop();
270 else {
271 printk(KERN_CRIT PFX
272 "Unexpected close, not stopping watchdog!\n");
273 ali_keepalive();
274 }
275 clear_bit(0, &ali_is_open);
276 ali_expect_release = 0;
277 return 0;
278}
279
280/*
281 * ali_notify_sys - System down notifier
282 *
283 * Notifier for system down
284 */
285
286
287static int ali_notify_sys(struct notifier_block *this,
288 unsigned long code, void *unused)
289{
290 if (code == SYS_DOWN || code == SYS_HALT)
291 ali_stop(); /* Turn the WDT off */
292 return NOTIFY_DONE;
293}
294
295/*
296 * Data for PCI driver interface
297 *
298 * This data only exists for exporting the supported
299 * PCI ids via MODULE_DEVICE_TABLE. We do not actually
300 * register a pci_driver, because someone else might one day
301 * want to register another driver on the same PCI id.
302 */
303
304static DEFINE_PCI_DEVICE_TABLE(ali_pci_tbl) __used = {
305 { PCI_VENDOR_ID_AL, 0x1533, PCI_ANY_ID, PCI_ANY_ID,},
306 { PCI_VENDOR_ID_AL, 0x1535, PCI_ANY_ID, PCI_ANY_ID,},
307 { 0, },
308};
309MODULE_DEVICE_TABLE(pci, ali_pci_tbl);
310
311/*
312 * ali_find_watchdog - find a 1535 and 7101
313 *
314 * Scans the PCI hardware for a 1535 series bridge and matching 7101
315 * watchdog device. This may be overtight but it is better to be safe
316 */
317
318static int __init ali_find_watchdog(void)
319{
320 struct pci_dev *pdev;
321 u32 wdog;
322
323 /* Check for a 1533/1535 series bridge */
324 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1535, NULL);
325 if (pdev == NULL)
326 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1533, NULL);
327 if (pdev == NULL)
328 return -ENODEV;
329 pci_dev_put(pdev);
330
331 /* Check for the a 7101 PMU */
332 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x7101, NULL);
333 if (pdev == NULL)
334 return -ENODEV;
335
336 if (pci_enable_device(pdev)) {
337 pci_dev_put(pdev);
338 return -EIO;
339 }
340
341 ali_pci = pdev;
342
343 /*
344 * Initialize the timer bits
345 */
346 pci_read_config_dword(pdev, 0xCC, &wdog);
347
348 /* Timer bits */
349 wdog &= ~0x3F;
350 /* Issued events */
351 wdog &= ~((1 << 27)|(1 << 26)|(1 << 25)|(1 << 24));
352 /* No monitor bits */
353 wdog &= ~((1 << 16)|(1 << 13)|(1 << 12)|(1 << 11)|(1 << 10)|(1 << 9));
354
355 pci_write_config_dword(pdev, 0xCC, wdog);
356
357 return 0;
358}
359
360/*
361 * Kernel Interfaces
362 */
363
364static const struct file_operations ali_fops = {
365 .owner = THIS_MODULE,
366 .llseek = no_llseek,
367 .write = ali_write,
368 .unlocked_ioctl = ali_ioctl,
369 .open = ali_open,
370 .release = ali_release,
371};
372
373static struct miscdevice ali_miscdev = {
374 .minor = WATCHDOG_MINOR,
375 .name = "watchdog",
376 .fops = &ali_fops,
377};
378
379static struct notifier_block ali_notifier = {
380 .notifier_call = ali_notify_sys,
381};
382
383/*
384 * watchdog_init - module initialiser
385 *
386 * Scan for a suitable watchdog and if so initialize it. Return an error
387 * if we cannot, the error causes the module to unload
388 */
389
390static int __init watchdog_init(void)
391{
392 int ret;
393
394 /* Check whether or not the hardware watchdog is there */
395 if (ali_find_watchdog() != 0)
396 return -ENODEV;
397
398 /* Check that the timeout value is within it's range;
399 if not reset to the default */
400 if (timeout < 1 || timeout >= 18000) {
401 timeout = WATCHDOG_TIMEOUT;
402 printk(KERN_INFO PFX
403 "timeout value must be 0 < timeout < 18000, using %d\n",
404 timeout);
405 }
406
407 /* Calculate the watchdog's timeout */
408 ali_settimer(timeout);
409
410 ret = register_reboot_notifier(&ali_notifier);
411 if (ret != 0) {
412 printk(KERN_ERR PFX
413 "cannot register reboot notifier (err=%d)\n", ret);
414 goto out;
415 }
416
417 ret = misc_register(&ali_miscdev);
418 if (ret != 0) {
419 printk(KERN_ERR PFX
420 "cannot register miscdev on minor=%d (err=%d)\n",
421 WATCHDOG_MINOR, ret);
422 goto unreg_reboot;
423 }
424
425 printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
426 timeout, nowayout);
427
428out:
429 return ret;
430unreg_reboot:
431 unregister_reboot_notifier(&ali_notifier);
432 goto out;
433}
434
435/*
436 * watchdog_exit - module de-initialiser
437 *
438 * Called while unloading a successfully installed watchdog module.
439 */
440
441static void __exit watchdog_exit(void)
442{
443 /* Stop the timer before we leave */
444 ali_stop();
445
446 /* Deregister */
447 misc_deregister(&ali_miscdev);
448 unregister_reboot_notifier(&ali_notifier);
449 pci_dev_put(ali_pci);
450}
451
452module_init(watchdog_init);
453module_exit(watchdog_exit);
454
455MODULE_AUTHOR("Alan Cox");
456MODULE_DESCRIPTION("ALi M1535 PMU Watchdog Timer driver");
457MODULE_LICENSE("GPL");
458MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
1/*
2 * Watchdog for the 7101 PMU version found in the ALi M1535 chipsets
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/module.h>
13#include <linux/moduleparam.h>
14#include <linux/types.h>
15#include <linux/miscdevice.h>
16#include <linux/watchdog.h>
17#include <linux/ioport.h>
18#include <linux/notifier.h>
19#include <linux/reboot.h>
20#include <linux/init.h>
21#include <linux/fs.h>
22#include <linux/pci.h>
23#include <linux/uaccess.h>
24#include <linux/io.h>
25
26#define WATCHDOG_NAME "ALi_M1535"
27#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
28
29/* internal variables */
30static unsigned long ali_is_open;
31static char ali_expect_release;
32static struct pci_dev *ali_pci;
33static u32 ali_timeout_bits; /* stores the computed timeout */
34static DEFINE_SPINLOCK(ali_lock); /* Guards the hardware */
35
36/* module parameters */
37static int timeout = WATCHDOG_TIMEOUT;
38module_param(timeout, int, 0);
39MODULE_PARM_DESC(timeout,
40 "Watchdog timeout in seconds. (0 < timeout < 18000, default="
41 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
42
43static bool nowayout = WATCHDOG_NOWAYOUT;
44module_param(nowayout, bool, 0);
45MODULE_PARM_DESC(nowayout,
46 "Watchdog cannot be stopped once started (default="
47 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
48
49/*
50 * ali_start - start watchdog countdown
51 *
52 * Starts the timer running providing the timer has a counter
53 * configuration set.
54 */
55
56static void ali_start(void)
57{
58 u32 val;
59
60 spin_lock(&ali_lock);
61
62 pci_read_config_dword(ali_pci, 0xCC, &val);
63 val &= ~0x3F; /* Mask count */
64 val |= (1 << 25) | ali_timeout_bits;
65 pci_write_config_dword(ali_pci, 0xCC, val);
66
67 spin_unlock(&ali_lock);
68}
69
70/*
71 * ali_stop - stop the timer countdown
72 *
73 * Stop the ALi watchdog countdown
74 */
75
76static void ali_stop(void)
77{
78 u32 val;
79
80 spin_lock(&ali_lock);
81
82 pci_read_config_dword(ali_pci, 0xCC, &val);
83 val &= ~0x3F; /* Mask count to zero (disabled) */
84 val &= ~(1 << 25); /* and for safety mask the reset enable */
85 pci_write_config_dword(ali_pci, 0xCC, val);
86
87 spin_unlock(&ali_lock);
88}
89
90/*
91 * ali_keepalive - send a keepalive to the watchdog
92 *
93 * Send a keepalive to the timer (actually we restart the timer).
94 */
95
96static void ali_keepalive(void)
97{
98 ali_start();
99}
100
101/*
102 * ali_settimer - compute the timer reload value
103 * @t: time in seconds
104 *
105 * Computes the timeout values needed
106 */
107
108static int ali_settimer(int t)
109{
110 if (t < 0)
111 return -EINVAL;
112 else if (t < 60)
113 ali_timeout_bits = t|(1 << 6);
114 else if (t < 3600)
115 ali_timeout_bits = (t / 60)|(1 << 7);
116 else if (t < 18000)
117 ali_timeout_bits = (t / 300)|(1 << 6)|(1 << 7);
118 else
119 return -EINVAL;
120
121 timeout = t;
122 return 0;
123}
124
125/*
126 * /dev/watchdog handling
127 */
128
129/*
130 * ali_write - writes to ALi watchdog
131 * @file: file from VFS
132 * @data: user address of data
133 * @len: length of data
134 * @ppos: pointer to the file offset
135 *
136 * Handle a write to the ALi watchdog. Writing to the file pings
137 * the watchdog and resets it. Writing the magic 'V' sequence allows
138 * the next close to turn off the watchdog.
139 */
140
141static ssize_t ali_write(struct file *file, const char __user *data,
142 size_t len, loff_t *ppos)
143{
144 /* See if we got the magic character 'V' and reload the timer */
145 if (len) {
146 if (!nowayout) {
147 size_t i;
148
149 /* note: just in case someone wrote the
150 magic character five months ago... */
151 ali_expect_release = 0;
152
153 /* scan to see whether or not we got
154 the magic character */
155 for (i = 0; i != len; i++) {
156 char c;
157 if (get_user(c, data + i))
158 return -EFAULT;
159 if (c == 'V')
160 ali_expect_release = 42;
161 }
162 }
163
164 /* someone wrote to us, we should reload the timer */
165 ali_start();
166 }
167 return len;
168}
169
170/*
171 * ali_ioctl - handle watchdog ioctls
172 * @file: VFS file pointer
173 * @cmd: ioctl number
174 * @arg: arguments to the ioctl
175 *
176 * Handle the watchdog ioctls supported by the ALi driver. Really
177 * we want an extension to enable irq ack monitoring and the like
178 */
179
180static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
181{
182 void __user *argp = (void __user *)arg;
183 int __user *p = argp;
184 static const struct watchdog_info ident = {
185 .options = WDIOF_KEEPALIVEPING |
186 WDIOF_SETTIMEOUT |
187 WDIOF_MAGICCLOSE,
188 .firmware_version = 0,
189 .identity = "ALi M1535 WatchDog Timer",
190 };
191
192 switch (cmd) {
193 case WDIOC_GETSUPPORT:
194 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
195
196 case WDIOC_GETSTATUS:
197 case WDIOC_GETBOOTSTATUS:
198 return put_user(0, p);
199 case WDIOC_SETOPTIONS:
200 {
201 int new_options, retval = -EINVAL;
202
203 if (get_user(new_options, p))
204 return -EFAULT;
205 if (new_options & WDIOS_DISABLECARD) {
206 ali_stop();
207 retval = 0;
208 }
209 if (new_options & WDIOS_ENABLECARD) {
210 ali_start();
211 retval = 0;
212 }
213 return retval;
214 }
215 case WDIOC_KEEPALIVE:
216 ali_keepalive();
217 return 0;
218 case WDIOC_SETTIMEOUT:
219 {
220 int new_timeout;
221 if (get_user(new_timeout, p))
222 return -EFAULT;
223 if (ali_settimer(new_timeout))
224 return -EINVAL;
225 ali_keepalive();
226 /* Fall */
227 }
228 case WDIOC_GETTIMEOUT:
229 return put_user(timeout, p);
230 default:
231 return -ENOTTY;
232 }
233}
234
235/*
236 * ali_open - handle open of ali watchdog
237 * @inode: inode from VFS
238 * @file: file from VFS
239 *
240 * Open the ALi watchdog device. Ensure only one person opens it
241 * at a time. Also start the watchdog running.
242 */
243
244static int ali_open(struct inode *inode, struct file *file)
245{
246 /* /dev/watchdog can only be opened once */
247 if (test_and_set_bit(0, &ali_is_open))
248 return -EBUSY;
249
250 /* Activate */
251 ali_start();
252 return nonseekable_open(inode, file);
253}
254
255/*
256 * ali_release - close an ALi watchdog
257 * @inode: inode from VFS
258 * @file: file from VFS
259 *
260 * Close the ALi watchdog device. Actual shutdown of the timer
261 * only occurs if the magic sequence has been set.
262 */
263
264static int ali_release(struct inode *inode, struct file *file)
265{
266 /*
267 * Shut off the timer.
268 */
269 if (ali_expect_release == 42)
270 ali_stop();
271 else {
272 pr_crit("Unexpected close, not stopping watchdog!\n");
273 ali_keepalive();
274 }
275 clear_bit(0, &ali_is_open);
276 ali_expect_release = 0;
277 return 0;
278}
279
280/*
281 * ali_notify_sys - System down notifier
282 *
283 * Notifier for system down
284 */
285
286
287static int ali_notify_sys(struct notifier_block *this,
288 unsigned long code, void *unused)
289{
290 if (code == SYS_DOWN || code == SYS_HALT)
291 ali_stop(); /* Turn the WDT off */
292 return NOTIFY_DONE;
293}
294
295/*
296 * Data for PCI driver interface
297 *
298 * This data only exists for exporting the supported
299 * PCI ids via MODULE_DEVICE_TABLE. We do not actually
300 * register a pci_driver, because someone else might one day
301 * want to register another driver on the same PCI id.
302 */
303
304static const struct pci_device_id ali_pci_tbl[] __used = {
305 { PCI_VENDOR_ID_AL, 0x1533, PCI_ANY_ID, PCI_ANY_ID,},
306 { PCI_VENDOR_ID_AL, 0x1535, PCI_ANY_ID, PCI_ANY_ID,},
307 { 0, },
308};
309MODULE_DEVICE_TABLE(pci, ali_pci_tbl);
310
311/*
312 * ali_find_watchdog - find a 1535 and 7101
313 *
314 * Scans the PCI hardware for a 1535 series bridge and matching 7101
315 * watchdog device. This may be overtight but it is better to be safe
316 */
317
318static int __init ali_find_watchdog(void)
319{
320 struct pci_dev *pdev;
321 u32 wdog;
322
323 /* Check for a 1533/1535 series bridge */
324 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1535, NULL);
325 if (pdev == NULL)
326 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1533, NULL);
327 if (pdev == NULL)
328 return -ENODEV;
329 pci_dev_put(pdev);
330
331 /* Check for the a 7101 PMU */
332 pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x7101, NULL);
333 if (pdev == NULL)
334 return -ENODEV;
335
336 if (pci_enable_device(pdev)) {
337 pci_dev_put(pdev);
338 return -EIO;
339 }
340
341 ali_pci = pdev;
342
343 /*
344 * Initialize the timer bits
345 */
346 pci_read_config_dword(pdev, 0xCC, &wdog);
347
348 /* Timer bits */
349 wdog &= ~0x3F;
350 /* Issued events */
351 wdog &= ~((1 << 27)|(1 << 26)|(1 << 25)|(1 << 24));
352 /* No monitor bits */
353 wdog &= ~((1 << 16)|(1 << 13)|(1 << 12)|(1 << 11)|(1 << 10)|(1 << 9));
354
355 pci_write_config_dword(pdev, 0xCC, wdog);
356
357 return 0;
358}
359
360/*
361 * Kernel Interfaces
362 */
363
364static const struct file_operations ali_fops = {
365 .owner = THIS_MODULE,
366 .llseek = no_llseek,
367 .write = ali_write,
368 .unlocked_ioctl = ali_ioctl,
369 .open = ali_open,
370 .release = ali_release,
371};
372
373static struct miscdevice ali_miscdev = {
374 .minor = WATCHDOG_MINOR,
375 .name = "watchdog",
376 .fops = &ali_fops,
377};
378
379static struct notifier_block ali_notifier = {
380 .notifier_call = ali_notify_sys,
381};
382
383/*
384 * watchdog_init - module initialiser
385 *
386 * Scan for a suitable watchdog and if so initialize it. Return an error
387 * if we cannot, the error causes the module to unload
388 */
389
390static int __init watchdog_init(void)
391{
392 int ret;
393
394 /* Check whether or not the hardware watchdog is there */
395 if (ali_find_watchdog() != 0)
396 return -ENODEV;
397
398 /* Check that the timeout value is within it's range;
399 if not reset to the default */
400 if (timeout < 1 || timeout >= 18000) {
401 timeout = WATCHDOG_TIMEOUT;
402 pr_info("timeout value must be 0 < timeout < 18000, using %d\n",
403 timeout);
404 }
405
406 /* Calculate the watchdog's timeout */
407 ali_settimer(timeout);
408
409 ret = register_reboot_notifier(&ali_notifier);
410 if (ret != 0) {
411 pr_err("cannot register reboot notifier (err=%d)\n", ret);
412 goto out;
413 }
414
415 ret = misc_register(&ali_miscdev);
416 if (ret != 0) {
417 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
418 WATCHDOG_MINOR, ret);
419 goto unreg_reboot;
420 }
421
422 pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
423 timeout, nowayout);
424
425out:
426 return ret;
427unreg_reboot:
428 unregister_reboot_notifier(&ali_notifier);
429 goto out;
430}
431
432/*
433 * watchdog_exit - module de-initialiser
434 *
435 * Called while unloading a successfully installed watchdog module.
436 */
437
438static void __exit watchdog_exit(void)
439{
440 /* Stop the timer before we leave */
441 ali_stop();
442
443 /* Deregister */
444 misc_deregister(&ali_miscdev);
445 unregister_reboot_notifier(&ali_notifier);
446 pci_dev_put(ali_pci);
447}
448
449module_init(watchdog_init);
450module_exit(watchdog_exit);
451
452MODULE_AUTHOR("Alan Cox");
453MODULE_DESCRIPTION("ALi M1535 PMU Watchdog Timer driver");
454MODULE_LICENSE("GPL");