]>
Commit | Line | Data |
---|---|---|
03ec5856 FF |
1 | /* |
2 | * IDT Interprise 79RC32434 watchdog driver | |
3 | * | |
4 | * Copyright (C) 2006, Ondrej Zajicek <santiago@crfreenet.org> | |
5 | * Copyright (C) 2008, Florian Fainelli <florian@openwrt.org> | |
6 | * | |
7 | * based on | |
8 | * SoftDog 0.05: A Software Watchdog Device | |
9 | * | |
10 | * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | * | |
17 | */ | |
18 | ||
19 | #include <linux/module.h> | |
20 | #include <linux/types.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/fs.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/miscdevice.h> | |
25 | #include <linux/watchdog.h> | |
26 | #include <linux/reboot.h> | |
27 | #include <linux/smp_lock.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/platform_device.h> | |
30 | #include <linux/uaccess.h> | |
31 | ||
32 | #include <asm/bootinfo.h> | |
33 | #include <asm/time.h> | |
34 | #include <asm/mach-rc32434/integ.h> | |
35 | ||
36 | #define MAX_TIMEOUT 20 | |
37 | #define RC32434_WDT_INTERVAL (15 * HZ) | |
38 | ||
39 | #define VERSION "0.2" | |
40 | ||
41 | static struct { | |
42 | struct completion stop; | |
43 | int running; | |
44 | struct timer_list timer; | |
45 | int queue; | |
46 | int default_ticks; | |
47 | unsigned long inuse; | |
48 | } rc32434_wdt_device; | |
49 | ||
50 | static struct integ __iomem *wdt_reg; | |
51 | static int ticks = 100 * HZ; | |
52 | ||
53 | static int expect_close; | |
54 | static int timeout; | |
55 | ||
56 | static int nowayout = WATCHDOG_NOWAYOUT; | |
57 | module_param(nowayout, int, 0); | |
58 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" | |
59 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | |
60 | ||
61 | ||
62 | static void rc32434_wdt_start(void) | |
63 | { | |
64 | u32 val; | |
65 | ||
66 | if (!rc32434_wdt_device.inuse) { | |
67 | writel(0, &wdt_reg->wtcount); | |
68 | ||
69 | val = RC32434_ERR_WRE; | |
70 | writel(readl(&wdt_reg->errcs) | val, &wdt_reg->errcs); | |
71 | ||
72 | val = RC32434_WTC_EN; | |
73 | writel(readl(&wdt_reg->wtc) | val, &wdt_reg->wtc); | |
74 | } | |
75 | rc32434_wdt_device.running++; | |
76 | } | |
77 | ||
78 | static void rc32434_wdt_stop(void) | |
79 | { | |
80 | u32 val; | |
81 | ||
82 | if (rc32434_wdt_device.running) { | |
83 | ||
84 | val = ~RC32434_WTC_EN; | |
85 | writel(readl(&wdt_reg->wtc) & val, &wdt_reg->wtc); | |
86 | ||
87 | val = ~RC32434_ERR_WRE; | |
88 | writel(readl(&wdt_reg->errcs) & val, &wdt_reg->errcs); | |
89 | ||
90 | rc32434_wdt_device.running = 0; | |
91 | } | |
92 | } | |
93 | ||
94 | static void rc32434_wdt_set(int new_timeout) | |
95 | { | |
96 | u32 cmp = new_timeout * HZ; | |
97 | u32 state, val; | |
98 | ||
99 | timeout = new_timeout; | |
100 | /* | |
101 | * store and disable WTC | |
102 | */ | |
103 | state = (u32)(readl(&wdt_reg->wtc) & RC32434_WTC_EN); | |
104 | val = ~RC32434_WTC_EN; | |
105 | writel(readl(&wdt_reg->wtc) & val, &wdt_reg->wtc); | |
106 | ||
107 | writel(0, &wdt_reg->wtcount); | |
108 | writel(cmp, &wdt_reg->wtcompare); | |
109 | ||
110 | /* | |
111 | * restore WTC | |
112 | */ | |
113 | ||
114 | writel(readl(&wdt_reg->wtc) | state, &wdt_reg); | |
115 | } | |
116 | ||
117 | static void rc32434_wdt_reset(void) | |
118 | { | |
119 | ticks = rc32434_wdt_device.default_ticks; | |
120 | } | |
121 | ||
122 | static void rc32434_wdt_update(unsigned long unused) | |
123 | { | |
124 | if (rc32434_wdt_device.running) | |
125 | ticks--; | |
126 | ||
127 | writel(0, &wdt_reg->wtcount); | |
128 | ||
129 | if (rc32434_wdt_device.queue && ticks) | |
130 | mod_timer(&rc32434_wdt_device.timer, | |
131 | jiffies + RC32434_WDT_INTERVAL); | |
132 | else | |
133 | complete(&rc32434_wdt_device.stop); | |
134 | } | |
135 | ||
136 | static int rc32434_wdt_open(struct inode *inode, struct file *file) | |
137 | { | |
138 | if (test_and_set_bit(0, &rc32434_wdt_device.inuse)) | |
139 | return -EBUSY; | |
140 | ||
141 | if (nowayout) | |
142 | __module_get(THIS_MODULE); | |
143 | ||
144 | return nonseekable_open(inode, file); | |
145 | } | |
146 | ||
147 | static int rc32434_wdt_release(struct inode *inode, struct file *file) | |
148 | { | |
149 | if (expect_close && nowayout == 0) { | |
150 | rc32434_wdt_stop(); | |
151 | printk(KERN_INFO KBUILD_MODNAME ": disabling watchdog timer\n"); | |
152 | module_put(THIS_MODULE); | |
153 | } else | |
154 | printk(KERN_CRIT KBUILD_MODNAME | |
155 | ": device closed unexpectedly. WDT will not stop !\n"); | |
156 | ||
157 | clear_bit(0, &rc32434_wdt_device.inuse); | |
158 | return 0; | |
159 | } | |
160 | ||
161 | static ssize_t rc32434_wdt_write(struct file *file, const char *data, | |
162 | size_t len, loff_t *ppos) | |
163 | { | |
164 | if (len) { | |
165 | if (!nowayout) { | |
166 | size_t i; | |
167 | ||
168 | /* In case it was set long ago */ | |
169 | expect_close = 0; | |
170 | ||
171 | for (i = 0; i != len; i++) { | |
172 | char c; | |
173 | if (get_user(c, data + i)) | |
174 | return -EFAULT; | |
175 | if (c == 'V') | |
176 | expect_close = 1; | |
177 | } | |
178 | } | |
179 | rc32434_wdt_update(0); | |
180 | return len; | |
181 | } | |
182 | return 0; | |
183 | } | |
184 | ||
185 | static int rc32434_wdt_ioctl(struct inode *inode, struct file *file, | |
186 | unsigned int cmd, unsigned long arg) | |
187 | { | |
188 | void __user *argp = (void __user *)arg; | |
189 | int new_timeout; | |
190 | unsigned int value; | |
191 | static struct watchdog_info ident = { | |
192 | .options = WDIOF_SETTIMEOUT | | |
193 | WDIOF_KEEPALIVEPING | | |
194 | WDIOF_MAGICCLOSE, | |
195 | .identity = "RC32434_WDT Watchdog", | |
196 | }; | |
197 | switch (cmd) { | |
198 | case WDIOC_KEEPALIVE: | |
199 | rc32434_wdt_reset(); | |
200 | break; | |
201 | case WDIOC_GETSTATUS: | |
202 | case WDIOC_GETBOOTSTATUS: | |
203 | value = readl(&wdt_reg->wtcount); | |
204 | if (copy_to_user(argp, &value, sizeof(int))) | |
205 | return -EFAULT; | |
206 | break; | |
207 | case WDIOC_GETSUPPORT: | |
208 | if (copy_to_user(argp, &ident, sizeof(ident))) | |
209 | return -EFAULT; | |
210 | break; | |
211 | case WDIOC_SETOPTIONS: | |
212 | if (copy_from_user(&value, argp, sizeof(int))) | |
213 | return -EFAULT; | |
214 | switch (value) { | |
215 | case WDIOS_ENABLECARD: | |
216 | rc32434_wdt_start(); | |
217 | break; | |
218 | case WDIOS_DISABLECARD: | |
219 | rc32434_wdt_stop(); | |
220 | default: | |
221 | return -EINVAL; | |
222 | } | |
223 | break; | |
224 | case WDIOC_SETTIMEOUT: | |
225 | if (copy_from_user(&new_timeout, argp, sizeof(int))) | |
226 | return -EFAULT; | |
227 | if (new_timeout < 1) | |
228 | return -EINVAL; | |
229 | if (new_timeout > MAX_TIMEOUT) | |
230 | return -EINVAL; | |
231 | rc32434_wdt_set(new_timeout); | |
232 | case WDIOC_GETTIMEOUT: | |
233 | return copy_to_user(argp, &timeout, sizeof(int)); | |
234 | default: | |
235 | return -ENOTTY; | |
236 | } | |
237 | ||
238 | return 0; | |
239 | } | |
240 | ||
241 | static struct file_operations rc32434_wdt_fops = { | |
242 | .owner = THIS_MODULE, | |
243 | .llseek = no_llseek, | |
244 | .write = rc32434_wdt_write, | |
245 | .ioctl = rc32434_wdt_ioctl, | |
246 | .open = rc32434_wdt_open, | |
247 | .release = rc32434_wdt_release, | |
248 | }; | |
249 | ||
250 | static struct miscdevice rc32434_wdt_miscdev = { | |
251 | .minor = WATCHDOG_MINOR, | |
252 | .name = "watchdog", | |
253 | .fops = &rc32434_wdt_fops, | |
254 | }; | |
255 | ||
256 | static char banner[] = KERN_INFO KBUILD_MODNAME | |
257 | ": Watchdog Timer version " VERSION ", timer margin: %d sec\n"; | |
258 | ||
259 | static int rc32434_wdt_probe(struct platform_device *pdev) | |
260 | { | |
261 | int ret; | |
262 | struct resource *r; | |
263 | ||
264 | r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rb500_wdt_res"); | |
265 | if (!r) { | |
266 | printk(KERN_ERR KBUILD_MODNAME | |
267 | "failed to retrieve resources\n"); | |
268 | return -ENODEV; | |
269 | } | |
270 | ||
271 | wdt_reg = ioremap_nocache(r->start, r->end - r->start); | |
272 | if (!wdt_reg) { | |
273 | printk(KERN_ERR KBUILD_MODNAME | |
274 | "failed to remap I/O resources\n"); | |
275 | return -ENXIO; | |
276 | } | |
277 | ||
278 | ret = misc_register(&rc32434_wdt_miscdev); | |
279 | ||
280 | if (ret < 0) { | |
281 | printk(KERN_ERR KBUILD_MODNAME | |
282 | "failed to register watchdog device\n"); | |
283 | goto unmap; | |
284 | } | |
285 | ||
286 | init_completion(&rc32434_wdt_device.stop); | |
287 | rc32434_wdt_device.queue = 0; | |
288 | ||
289 | clear_bit(0, &rc32434_wdt_device.inuse); | |
290 | ||
291 | setup_timer(&rc32434_wdt_device.timer, rc32434_wdt_update, 0L); | |
292 | ||
293 | rc32434_wdt_device.default_ticks = ticks; | |
294 | ||
295 | rc32434_wdt_start(); | |
296 | ||
297 | printk(banner, timeout); | |
298 | ||
299 | return 0; | |
300 | ||
301 | unmap: | |
302 | iounmap(wdt_reg); | |
303 | return ret; | |
304 | } | |
305 | ||
306 | static int rc32434_wdt_remove(struct platform_device *pdev) | |
307 | { | |
308 | if (rc32434_wdt_device.queue) { | |
309 | rc32434_wdt_device.queue = 0; | |
310 | wait_for_completion(&rc32434_wdt_device.stop); | |
311 | } | |
312 | misc_deregister(&rc32434_wdt_miscdev); | |
313 | ||
314 | iounmap(wdt_reg); | |
315 | ||
316 | return 0; | |
317 | } | |
318 | ||
319 | static struct platform_driver rc32434_wdt = { | |
320 | .probe = rc32434_wdt_probe, | |
321 | .remove = rc32434_wdt_remove, | |
322 | .driver = { | |
323 | .name = "rc32434_wdt", | |
324 | } | |
325 | }; | |
326 | ||
327 | static int __init rc32434_wdt_init(void) | |
328 | { | |
329 | return platform_driver_register(&rc32434_wdt); | |
330 | } | |
331 | ||
332 | static void __exit rc32434_wdt_exit(void) | |
333 | { | |
334 | platform_driver_unregister(&rc32434_wdt); | |
335 | } | |
336 | ||
337 | module_init(rc32434_wdt_init); | |
338 | module_exit(rc32434_wdt_exit); | |
339 | ||
340 | MODULE_AUTHOR("Ondrej Zajicek <santiago@crfreenet.org>," | |
341 | "Florian Fainelli <florian@openwrt.org>"); | |
342 | MODULE_DESCRIPTION("Driver for the IDT RC32434 SoC watchdog"); | |
343 | MODULE_LICENSE("GPL"); | |
344 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |