diff options
author | David S. Miller <davem@davemloft.net> | 2008-06-10 05:22:26 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2008-06-10 05:22:26 -0400 |
commit | 65b53e4cc90e59936733b3b95b9451d2ca47528d (patch) | |
tree | 29932718192962671c48c3fd1ea017a6112459e8 /drivers/watchdog/geodewdt.c | |
parent | 788c0a53164c05c5ccdb1472474372b72ba74644 (diff) | |
parent | 2e761e0532a784816e7e822dbaaece8c5d4be14d (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
drivers/net/tg3.c
drivers/net/wireless/rt2x00/rt2x00dev.c
net/mac80211/ieee80211_i.h
Diffstat (limited to 'drivers/watchdog/geodewdt.c')
-rw-r--r-- | drivers/watchdog/geodewdt.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/watchdog/geodewdt.c b/drivers/watchdog/geodewdt.c new file mode 100644 index 000000000000..30d09cbbad94 --- /dev/null +++ b/drivers/watchdog/geodewdt.c | |||
@@ -0,0 +1,308 @@ | |||
1 | /* Watchdog timer for the Geode GX/LX with the CS5535/CS5536 companion chip | ||
2 | * | ||
3 | * Copyright (C) 2006-2007, Advanced Micro Devices, Inc. | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or | ||
6 | * modify it under the terms of the GNU General Public License | ||
7 | * as published by the Free Software Foundation; either version | ||
8 | * 2 of the License, or (at your option) any later version. | ||
9 | */ | ||
10 | |||
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/fs.h> | ||
18 | #include <linux/platform_device.h> | ||
19 | #include <linux/reboot.h> | ||
20 | |||
21 | #include <asm/uaccess.h> | ||
22 | #include <asm/geode.h> | ||
23 | |||
24 | #define GEODEWDT_HZ 500 | ||
25 | #define GEODEWDT_SCALE 6 | ||
26 | #define GEODEWDT_MAX_SECONDS 131 | ||
27 | |||
28 | #define WDT_FLAGS_OPEN 1 | ||
29 | #define WDT_FLAGS_ORPHAN 2 | ||
30 | |||
31 | #define DRV_NAME "geodewdt" | ||
32 | #define WATCHDOG_NAME "Geode GX/LX WDT" | ||
33 | #define WATCHDOG_TIMEOUT 60 | ||
34 | |||
35 | static int timeout = WATCHDOG_TIMEOUT; | ||
36 | module_param(timeout, int, 0); | ||
37 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=131, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); | ||
38 | |||
39 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
40 | module_param(nowayout, int, 0); | ||
41 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
42 | |||
43 | static struct platform_device *geodewdt_platform_device; | ||
44 | static unsigned long wdt_flags; | ||
45 | static int wdt_timer; | ||
46 | static int safe_close; | ||
47 | |||
48 | static void geodewdt_ping(void) | ||
49 | { | ||
50 | /* Stop the counter */ | ||
51 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); | ||
52 | |||
53 | /* Reset the counter */ | ||
54 | geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); | ||
55 | |||
56 | /* Enable the counter */ | ||
57 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN); | ||
58 | } | ||
59 | |||
60 | static void geodewdt_disable(void) | ||
61 | { | ||
62 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); | ||
63 | geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); | ||
64 | } | ||
65 | |||
66 | static int geodewdt_set_heartbeat(int val) | ||
67 | { | ||
68 | if (val < 1 || val > GEODEWDT_MAX_SECONDS) | ||
69 | return -EINVAL; | ||
70 | |||
71 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); | ||
72 | geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2, val * GEODEWDT_HZ); | ||
73 | geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); | ||
74 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN); | ||
75 | |||
76 | timeout = val; | ||
77 | return 0; | ||
78 | } | ||
79 | |||
80 | static int | ||
81 | geodewdt_open(struct inode *inode, struct file *file) | ||
82 | { | ||
83 | if (test_and_set_bit(WDT_FLAGS_OPEN, &wdt_flags)) | ||
84 | return -EBUSY; | ||
85 | |||
86 | if (!test_and_clear_bit(WDT_FLAGS_ORPHAN, &wdt_flags)) | ||
87 | __module_get(THIS_MODULE); | ||
88 | |||
89 | geodewdt_ping(); | ||
90 | return nonseekable_open(inode, file); | ||
91 | } | ||
92 | |||
93 | static int | ||
94 | geodewdt_release(struct inode *inode, struct file *file) | ||
95 | { | ||
96 | if (safe_close) { | ||
97 | geodewdt_disable(); | ||
98 | module_put(THIS_MODULE); | ||
99 | } | ||
100 | else { | ||
101 | printk(KERN_CRIT "Unexpected close - watchdog is not stopping.\n"); | ||
102 | geodewdt_ping(); | ||
103 | |||
104 | set_bit(WDT_FLAGS_ORPHAN, &wdt_flags); | ||
105 | } | ||
106 | |||
107 | clear_bit(WDT_FLAGS_OPEN, &wdt_flags); | ||
108 | safe_close = 0; | ||
109 | return 0; | ||
110 | } | ||
111 | |||
112 | static ssize_t | ||
113 | geodewdt_write(struct file *file, const char __user *data, size_t len, | ||
114 | loff_t *ppos) | ||
115 | { | ||
116 | if(len) { | ||
117 | if (!nowayout) { | ||
118 | size_t i; | ||
119 | safe_close = 0; | ||
120 | |||
121 | for (i = 0; i != len; i++) { | ||
122 | char c; | ||
123 | |||
124 | if (get_user(c, data + i)) | ||
125 | return -EFAULT; | ||
126 | |||
127 | if (c == 'V') | ||
128 | safe_close = 1; | ||
129 | } | ||
130 | } | ||
131 | |||
132 | geodewdt_ping(); | ||
133 | } | ||
134 | return len; | ||
135 | } | ||
136 | |||
137 | static int | ||
138 | geodewdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | ||
139 | unsigned long arg) | ||
140 | { | ||
141 | void __user *argp = (void __user *)arg; | ||
142 | int __user *p = argp; | ||
143 | int interval; | ||
144 | |||
145 | static struct watchdog_info ident = { | ||
146 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | ||
147 | | WDIOF_MAGICCLOSE, | ||
148 | .firmware_version = 1, | ||
149 | .identity = WATCHDOG_NAME, | ||
150 | }; | ||
151 | |||
152 | switch(cmd) { | ||
153 | case WDIOC_GETSUPPORT: | ||
154 | return copy_to_user(argp, &ident, | ||
155 | sizeof(ident)) ? -EFAULT : 0; | ||
156 | break; | ||
157 | |||
158 | case WDIOC_GETSTATUS: | ||
159 | case WDIOC_GETBOOTSTATUS: | ||
160 | return put_user(0, p); | ||
161 | |||
162 | case WDIOC_KEEPALIVE: | ||
163 | geodewdt_ping(); | ||
164 | return 0; | ||
165 | |||
166 | case WDIOC_SETTIMEOUT: | ||
167 | if (get_user(interval, p)) | ||
168 | return -EFAULT; | ||
169 | |||
170 | if (geodewdt_set_heartbeat(interval)) | ||
171 | return -EINVAL; | ||
172 | |||
173 | /* Fall through */ | ||
174 | |||
175 | case WDIOC_GETTIMEOUT: | ||
176 | return put_user(timeout, p); | ||
177 | |||
178 | case WDIOC_SETOPTIONS: | ||
179 | { | ||
180 | int options, ret = -EINVAL; | ||
181 | |||
182 | if (get_user(options, p)) | ||
183 | return -EFAULT; | ||
184 | |||
185 | if (options & WDIOS_DISABLECARD) { | ||
186 | geodewdt_disable(); | ||
187 | ret = 0; | ||
188 | } | ||
189 | |||
190 | if (options & WDIOS_ENABLECARD) { | ||
191 | geodewdt_ping(); | ||
192 | ret = 0; | ||
193 | } | ||
194 | |||
195 | return ret; | ||
196 | } | ||
197 | default: | ||
198 | return -ENOTTY; | ||
199 | } | ||
200 | |||
201 | return 0; | ||
202 | } | ||
203 | |||
204 | static const struct file_operations geodewdt_fops = { | ||
205 | .owner = THIS_MODULE, | ||
206 | .llseek = no_llseek, | ||
207 | .write = geodewdt_write, | ||
208 | .ioctl = geodewdt_ioctl, | ||
209 | .open = geodewdt_open, | ||
210 | .release = geodewdt_release, | ||
211 | }; | ||
212 | |||
213 | static struct miscdevice geodewdt_miscdev = { | ||
214 | .minor = WATCHDOG_MINOR, | ||
215 | .name = "watchdog", | ||
216 | .fops = &geodewdt_fops | ||
217 | }; | ||
218 | |||
219 | static int __devinit | ||
220 | geodewdt_probe(struct platform_device *dev) | ||
221 | { | ||
222 | int ret, timer; | ||
223 | |||
224 | timer = geode_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING); | ||
225 | |||
226 | if (timer == -1) { | ||
227 | printk(KERN_ERR "geodewdt: No timers were available\n"); | ||
228 | return -ENODEV; | ||
229 | } | ||
230 | |||
231 | wdt_timer = timer; | ||
232 | |||
233 | /* Set up the timer */ | ||
234 | |||
235 | geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, | ||
236 | GEODEWDT_SCALE | (3 << 8)); | ||
237 | |||
238 | /* Set up comparator 2 to reset when the event fires */ | ||
239 | geode_mfgpt_toggle_event(wdt_timer, MFGPT_CMP2, MFGPT_EVENT_RESET, 1); | ||
240 | |||
241 | /* Set up the initial timeout */ | ||
242 | |||
243 | geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2, | ||
244 | timeout * GEODEWDT_HZ); | ||
245 | |||
246 | ret = misc_register(&geodewdt_miscdev); | ||
247 | |||
248 | return ret; | ||
249 | } | ||
250 | |||
251 | static int __devexit | ||
252 | geodewdt_remove(struct platform_device *dev) | ||
253 | { | ||
254 | misc_deregister(&geodewdt_miscdev); | ||
255 | return 0; | ||
256 | } | ||
257 | |||
258 | static void | ||
259 | geodewdt_shutdown(struct platform_device *dev) | ||
260 | { | ||
261 | geodewdt_disable(); | ||
262 | } | ||
263 | |||
264 | static struct platform_driver geodewdt_driver = { | ||
265 | .probe = geodewdt_probe, | ||
266 | .remove = __devexit_p(geodewdt_remove), | ||
267 | .shutdown = geodewdt_shutdown, | ||
268 | .driver = { | ||
269 | .owner = THIS_MODULE, | ||
270 | .name = DRV_NAME, | ||
271 | }, | ||
272 | }; | ||
273 | |||
274 | static int __init | ||
275 | geodewdt_init(void) | ||
276 | { | ||
277 | int ret; | ||
278 | |||
279 | ret = platform_driver_register(&geodewdt_driver); | ||
280 | if (ret) | ||
281 | return ret; | ||
282 | |||
283 | geodewdt_platform_device = platform_device_register_simple(DRV_NAME, -1, NULL, 0); | ||
284 | if (IS_ERR(geodewdt_platform_device)) { | ||
285 | ret = PTR_ERR(geodewdt_platform_device); | ||
286 | goto err; | ||
287 | } | ||
288 | |||
289 | return 0; | ||
290 | err: | ||
291 | platform_driver_unregister(&geodewdt_driver); | ||
292 | return ret; | ||
293 | } | ||
294 | |||
295 | static void __exit | ||
296 | geodewdt_exit(void) | ||
297 | { | ||
298 | platform_device_unregister(geodewdt_platform_device); | ||
299 | platform_driver_unregister(&geodewdt_driver); | ||
300 | } | ||
301 | |||
302 | module_init(geodewdt_init); | ||
303 | module_exit(geodewdt_exit); | ||
304 | |||
305 | MODULE_AUTHOR("Advanced Micro Devices, Inc"); | ||
306 | MODULE_DESCRIPTION("Geode GX/LX Watchdog Driver"); | ||
307 | MODULE_LICENSE("GPL"); | ||
308 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||