diff options
Diffstat (limited to 'arch/x86/mach-rdc321x/wdt.c')
-rw-r--r-- | arch/x86/mach-rdc321x/wdt.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/arch/x86/mach-rdc321x/wdt.c b/arch/x86/mach-rdc321x/wdt.c new file mode 100644 index 000000000000..ec5625ae7061 --- /dev/null +++ b/arch/x86/mach-rdc321x/wdt.c | |||
@@ -0,0 +1,275 @@ | |||
1 | /* | ||
2 | * RDC321x watchdog driver | ||
3 | * | ||
4 | * Copyright (C) 2007 Florian Fainelli <florian@openwrt.org> | ||
5 | * | ||
6 | * This driver is highly inspired from the cpu5_wdt driver | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify | ||
9 | * it under the terms of the GNU General Public License as published by | ||
10 | * the Free Software Foundation; either version 2 of the License, or | ||
11 | * (at your option) any later version. | ||
12 | * | ||
13 | * This program is distributed in the hope that it will be useful, | ||
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
16 | * GNU General Public License for more details. | ||
17 | * | ||
18 | * You should have received a copy of the GNU General Public License | ||
19 | * along with this program; if not, write to the Free Software | ||
20 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
21 | * | ||
22 | */ | ||
23 | |||
24 | #include <linux/module.h> | ||
25 | #include <linux/moduleparam.h> | ||
26 | #include <linux/types.h> | ||
27 | #include <linux/errno.h> | ||
28 | #include <linux/miscdevice.h> | ||
29 | #include <linux/fs.h> | ||
30 | #include <linux/init.h> | ||
31 | #include <linux/ioport.h> | ||
32 | #include <linux/timer.h> | ||
33 | #include <linux/completion.h> | ||
34 | #include <linux/jiffies.h> | ||
35 | #include <linux/platform_device.h> | ||
36 | #include <linux/watchdog.h> | ||
37 | #include <linux/io.h> | ||
38 | #include <linux/uaccess.h> | ||
39 | |||
40 | #include <asm/mach-rdc321x/rdc321x_defs.h> | ||
41 | |||
42 | #define RDC_WDT_MASK 0x80000000 /* Mask */ | ||
43 | #define RDC_WDT_EN 0x00800000 /* Enable bit */ | ||
44 | #define RDC_WDT_WTI 0x00200000 /* Generate CPU reset/NMI/WDT on timeout */ | ||
45 | #define RDC_WDT_RST 0x00100000 /* Reset bit */ | ||
46 | #define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */ | ||
47 | #define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */ | ||
48 | #define RDC_WDT_CNT 0x00000001 /* WDT count */ | ||
49 | |||
50 | #define RDC_CLS_TMR 0x80003844 /* Clear timer */ | ||
51 | |||
52 | #define RDC_WDT_INTERVAL (HZ/10+1) | ||
53 | |||
54 | int nowayout = WATCHDOG_NOWAYOUT; | ||
55 | module_param(nowayout, int, 0); | ||
56 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
57 | |||
58 | static int ticks = 1000; | ||
59 | |||
60 | /* some device data */ | ||
61 | |||
62 | static struct { | ||
63 | struct completion stop; | ||
64 | volatile int running; | ||
65 | struct timer_list timer; | ||
66 | volatile int queue; | ||
67 | int default_ticks; | ||
68 | unsigned long inuse; | ||
69 | } rdc321x_wdt_device; | ||
70 | |||
71 | /* generic helper functions */ | ||
72 | |||
73 | static void rdc321x_wdt_trigger(unsigned long unused) | ||
74 | { | ||
75 | if (rdc321x_wdt_device.running) | ||
76 | ticks--; | ||
77 | |||
78 | /* keep watchdog alive */ | ||
79 | outl(RDC_WDT_EN|inl(RDC3210_CFGREG_DATA), RDC3210_CFGREG_DATA); | ||
80 | |||
81 | /* requeue?? */ | ||
82 | if (rdc321x_wdt_device.queue && ticks) | ||
83 | mod_timer(&rdc321x_wdt_device.timer, | ||
84 | jiffies + RDC_WDT_INTERVAL); | ||
85 | else { | ||
86 | /* ticks doesn't matter anyway */ | ||
87 | complete(&rdc321x_wdt_device.stop); | ||
88 | } | ||
89 | |||
90 | } | ||
91 | |||
92 | static void rdc321x_wdt_reset(void) | ||
93 | { | ||
94 | ticks = rdc321x_wdt_device.default_ticks; | ||
95 | } | ||
96 | |||
97 | static void rdc321x_wdt_start(void) | ||
98 | { | ||
99 | if (!rdc321x_wdt_device.queue) { | ||
100 | rdc321x_wdt_device.queue = 1; | ||
101 | |||
102 | /* Clear the timer */ | ||
103 | outl(RDC_CLS_TMR, RDC3210_CFGREG_ADDR); | ||
104 | |||
105 | /* Enable watchdog and set the timeout to 81.92 us */ | ||
106 | outl(RDC_WDT_EN|RDC_WDT_CNT, RDC3210_CFGREG_DATA); | ||
107 | |||
108 | mod_timer(&rdc321x_wdt_device.timer, | ||
109 | jiffies + RDC_WDT_INTERVAL); | ||
110 | } | ||
111 | |||
112 | /* if process dies, counter is not decremented */ | ||
113 | rdc321x_wdt_device.running++; | ||
114 | } | ||
115 | |||
116 | static int rdc321x_wdt_stop(void) | ||
117 | { | ||
118 | if (rdc321x_wdt_device.running) | ||
119 | rdc321x_wdt_device.running = 0; | ||
120 | |||
121 | ticks = rdc321x_wdt_device.default_ticks; | ||
122 | |||
123 | return -EIO; | ||
124 | } | ||
125 | |||
126 | /* filesystem operations */ | ||
127 | |||
128 | static int rdc321x_wdt_open(struct inode *inode, struct file *file) | ||
129 | { | ||
130 | if (test_and_set_bit(0, &rdc321x_wdt_device.inuse)) | ||
131 | return -EBUSY; | ||
132 | |||
133 | return nonseekable_open(inode, file); | ||
134 | } | ||
135 | |||
136 | static int rdc321x_wdt_release(struct inode *inode, struct file *file) | ||
137 | { | ||
138 | clear_bit(0, &rdc321x_wdt_device.inuse); | ||
139 | return 0; | ||
140 | } | ||
141 | |||
142 | static int rdc321x_wdt_ioctl(struct inode *inode, struct file *file, | ||
143 | unsigned int cmd, unsigned long arg) | ||
144 | { | ||
145 | void __user *argp = (void __user *)arg; | ||
146 | unsigned int value; | ||
147 | static struct watchdog_info ident = { | ||
148 | .options = WDIOF_CARDRESET, | ||
149 | .identity = "RDC321x WDT", | ||
150 | }; | ||
151 | |||
152 | switch (cmd) { | ||
153 | case WDIOC_KEEPALIVE: | ||
154 | rdc321x_wdt_reset(); | ||
155 | break; | ||
156 | case WDIOC_GETSTATUS: | ||
157 | /* Read the value from the DATA register */ | ||
158 | value = inl(RDC3210_CFGREG_DATA); | ||
159 | if (copy_to_user(argp, &value, sizeof(int))) | ||
160 | return -EFAULT; | ||
161 | break; | ||
162 | case WDIOC_GETSUPPORT: | ||
163 | if (copy_to_user(argp, &ident, sizeof(ident))) | ||
164 | return -EFAULT; | ||
165 | break; | ||
166 | case WDIOC_SETOPTIONS: | ||
167 | if (copy_from_user(&value, argp, sizeof(int))) | ||
168 | return -EFAULT; | ||
169 | switch (value) { | ||
170 | case WDIOS_ENABLECARD: | ||
171 | rdc321x_wdt_start(); | ||
172 | break; | ||
173 | case WDIOS_DISABLECARD: | ||
174 | return rdc321x_wdt_stop(); | ||
175 | default: | ||
176 | return -EINVAL; | ||
177 | } | ||
178 | break; | ||
179 | default: | ||
180 | return -ENOTTY; | ||
181 | } | ||
182 | return 0; | ||
183 | } | ||
184 | |||
185 | static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf, | ||
186 | size_t count, loff_t *ppos) | ||
187 | { | ||
188 | if (!count) | ||
189 | return -EIO; | ||
190 | |||
191 | rdc321x_wdt_reset(); | ||
192 | |||
193 | return count; | ||
194 | } | ||
195 | |||
196 | static const struct file_operations rdc321x_wdt_fops = { | ||
197 | .owner = THIS_MODULE, | ||
198 | .llseek = no_llseek, | ||
199 | .ioctl = rdc321x_wdt_ioctl, | ||
200 | .open = rdc321x_wdt_open, | ||
201 | .write = rdc321x_wdt_write, | ||
202 | .release = rdc321x_wdt_release, | ||
203 | }; | ||
204 | |||
205 | static struct miscdevice rdc321x_wdt_misc = { | ||
206 | .minor = WATCHDOG_MINOR, | ||
207 | .name = "watchdog", | ||
208 | .fops = &rdc321x_wdt_fops, | ||
209 | }; | ||
210 | |||
211 | static int __devinit rdc321x_wdt_probe(struct platform_device *pdev) | ||
212 | { | ||
213 | int err; | ||
214 | |||
215 | err = misc_register(&rdc321x_wdt_misc); | ||
216 | if (err < 0) { | ||
217 | printk(KERN_ERR PFX "watchdog misc_register failed\n"); | ||
218 | return err; | ||
219 | } | ||
220 | |||
221 | /* Reset the watchdog */ | ||
222 | outl(RDC_WDT_RST, RDC3210_CFGREG_DATA); | ||
223 | |||
224 | init_completion(&rdc321x_wdt_device.stop); | ||
225 | rdc321x_wdt_device.queue = 0; | ||
226 | |||
227 | clear_bit(0, &rdc321x_wdt_device.inuse); | ||
228 | |||
229 | setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0); | ||
230 | |||
231 | rdc321x_wdt_device.default_ticks = ticks; | ||
232 | |||
233 | printk(KERN_INFO PFX "watchdog init success\n"); | ||
234 | |||
235 | return 0; | ||
236 | } | ||
237 | |||
238 | static int rdc321x_wdt_remove(struct platform_device *pdev) | ||
239 | { | ||
240 | if (rdc321x_wdt_device.queue) { | ||
241 | rdc321x_wdt_device.queue = 0; | ||
242 | wait_for_completion(&rdc321x_wdt_device.stop); | ||
243 | } | ||
244 | |||
245 | misc_deregister(&rdc321x_wdt_misc); | ||
246 | |||
247 | return 0; | ||
248 | } | ||
249 | |||
250 | static struct platform_driver rdc321x_wdt_driver = { | ||
251 | .probe = rdc321x_wdt_probe, | ||
252 | .remove = rdc321x_wdt_remove, | ||
253 | .driver = { | ||
254 | .owner = THIS_MODULE, | ||
255 | .name = "rdc321x-wdt", | ||
256 | }, | ||
257 | }; | ||
258 | |||
259 | static int __init rdc321x_wdt_init(void) | ||
260 | { | ||
261 | return platform_driver_register(&rdc321x_wdt_driver); | ||
262 | } | ||
263 | |||
264 | static void __exit rdc321x_wdt_exit(void) | ||
265 | { | ||
266 | platform_driver_unregister(&rdc321x_wdt_driver); | ||
267 | } | ||
268 | |||
269 | module_init(rdc321x_wdt_init); | ||
270 | module_exit(rdc321x_wdt_exit); | ||
271 | |||
272 | MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); | ||
273 | MODULE_DESCRIPTION("RDC321x watchdog driver"); | ||
274 | MODULE_LICENSE("GPL"); | ||
275 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||