Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 1 | /* |
| 2 | * w83697hf WDT driver |
| 3 | * |
| 4 | * (c) Copyright 2006 Marcus Junker <junker@anduras.de> |
| 5 | * |
| 6 | * Based on w83627hf_wdt.c advantechwdt.c which is based on wdt.c. |
| 7 | * Original copyright messages: |
| 8 | * |
| 9 | * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com> |
| 10 | * |
| 11 | * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl> |
| 12 | * |
| 13 | * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. |
| 14 | * http://www.redhat.com |
| 15 | * |
| 16 | * This program is free software; you can redistribute it and/or |
| 17 | * modify it under the terms of the GNU General Public License |
| 18 | * as published by the Free Software Foundation; either version |
| 19 | * 2 of the License, or (at your option) any later version. |
| 20 | * |
| 21 | * Neither Marcus Junker nor ANDURAS AG admit liability nor provide |
| 22 | * warranty for any of this software. This material is provided |
| 23 | * "AS-IS" and at no charge. |
| 24 | */ |
| 25 | |
| 26 | #include <linux/module.h> |
| 27 | #include <linux/moduleparam.h> |
| 28 | #include <linux/types.h> |
| 29 | #include <linux/miscdevice.h> |
| 30 | #include <linux/watchdog.h> |
| 31 | #include <linux/fs.h> |
| 32 | #include <linux/ioport.h> |
| 33 | #include <linux/notifier.h> |
| 34 | #include <linux/reboot.h> |
| 35 | #include <linux/init.h> |
Wim Van Sebroeck | ab9d441 | 2006-09-02 18:50:20 +0200 | [diff] [blame] | 36 | #include <linux/spinlock.h> |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 37 | |
| 38 | #include <asm/io.h> |
| 39 | #include <asm/uaccess.h> |
| 40 | #include <asm/system.h> |
| 41 | |
| 42 | #define WATCHDOG_NAME "w83697hf WDT" |
| 43 | #define PFX WATCHDOG_NAME ": " |
| 44 | #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ |
| 45 | |
| 46 | static unsigned long wdt_is_open; |
| 47 | static char expect_close; |
Wim Van Sebroeck | ab9d441 | 2006-09-02 18:50:20 +0200 | [diff] [blame] | 48 | static spinlock_t io_lock; |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 49 | |
| 50 | /* You must set this - there is no sane way to probe for this board. */ |
| 51 | static int wdt_io = 0x2E; |
| 52 | module_param(wdt_io, int, 0); |
| 53 | MODULE_PARM_DESC(wdt_io, "w83697hf WDT io port (default 0x2E)"); |
| 54 | |
| 55 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ |
| 56 | module_param(timeout, int, 0); |
| 57 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=63, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); |
| 58 | |
| 59 | static int nowayout = WATCHDOG_NOWAYOUT; |
| 60 | module_param(nowayout, int, 0); |
| 61 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); |
| 62 | |
| 63 | /* |
| 64 | * Kernel methods. |
| 65 | */ |
| 66 | |
| 67 | #define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */ |
| 68 | #define WDT_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */ |
| 69 | #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */ |
| 70 | |
| 71 | static void |
| 72 | w83697hf_select_wd_register(void) |
| 73 | { |
| 74 | outb_p(0x87, WDT_EFER); /* Enter extended function mode */ |
| 75 | outb_p(0x87, WDT_EFER); /* Again according to manual */ |
| 76 | |
| 77 | outb_p(0x29, WDT_EFER); /* select CR29 */ |
| 78 | outb_p(0x20, WDT_EFDR); /* select WDTO */ |
| 79 | |
| 80 | outb_p(0x07, WDT_EFER); /* point to logical device number reg */ |
| 81 | outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */ |
| 82 | outb_p(0x30, WDT_EFER); /* select CR30 */ |
| 83 | outb_p(0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */ |
| 84 | } |
| 85 | |
| 86 | static void |
| 87 | w83697hf_unselect_wd_register(void) |
| 88 | { |
| 89 | outb_p(0xAA, WDT_EFER); /* Leave extended function mode */ |
| 90 | } |
| 91 | |
| 92 | /* tyan motherboards seem to set F5 to 0x4C ? |
| 93 | * So explicitly init to appropriate value. */ |
| 94 | static void |
| 95 | w83697hf_init(void) |
| 96 | { |
| 97 | unsigned char t; |
| 98 | |
| 99 | w83697hf_select_wd_register(); |
| 100 | |
| 101 | outb_p(0xF3, WDT_EFER); /* Select CRF3 */ |
| 102 | |
| 103 | t=inb_p(WDT_EFDR); /* read CRF6 */ |
| 104 | if (t != 0) { |
| 105 | printk (KERN_INFO PFX "Watchdog already running. Resetting timeout to %d sec\n", timeout); |
| 106 | outb_p(timeout, WDT_EFDR); /* Write back to CRF6 */ |
| 107 | } |
| 108 | outb_p(0xF4, WDT_EFER); /* Select CRF4 */ |
| 109 | t=inb_p(WDT_EFDR); /* read CRF4 */ |
| 110 | t&=~0x0C; /* set second mode & disable keyboard turning off watchdog */ |
| 111 | outb_p(t, WDT_EFDR); /* Write back to CRF5 */ |
| 112 | |
| 113 | w83697hf_unselect_wd_register(); |
| 114 | } |
| 115 | |
| 116 | static void |
| 117 | wdt_ctrl(int timeout) |
| 118 | { |
Wim Van Sebroeck | ab9d441 | 2006-09-02 18:50:20 +0200 | [diff] [blame] | 119 | spin_lock(&io_lock); |
| 120 | |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 121 | w83697hf_select_wd_register(); |
| 122 | |
| 123 | outb_p(0xF4, WDT_EFER); /* Select CRF4 */ |
| 124 | outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */ |
| 125 | |
| 126 | w83697hf_unselect_wd_register(); |
Wim Van Sebroeck | ab9d441 | 2006-09-02 18:50:20 +0200 | [diff] [blame] | 127 | |
| 128 | spin_unlock(&io_lock); |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 129 | } |
| 130 | |
| 131 | static int |
| 132 | wdt_ping(void) |
| 133 | { |
| 134 | wdt_ctrl(timeout); |
| 135 | return 0; |
| 136 | } |
| 137 | |
| 138 | static int |
| 139 | wdt_disable(void) |
| 140 | { |
| 141 | wdt_ctrl(0); |
| 142 | return 0; |
| 143 | } |
| 144 | |
| 145 | static int |
| 146 | wdt_set_heartbeat(int t) |
| 147 | { |
| 148 | if ((t < 1) || (t > 63)) |
| 149 | return -EINVAL; |
| 150 | |
| 151 | timeout = t; |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | static ssize_t |
| 156 | wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) |
| 157 | { |
| 158 | if (count) { |
| 159 | if (!nowayout) { |
| 160 | size_t i; |
| 161 | |
| 162 | expect_close = 0; |
| 163 | |
| 164 | for (i = 0; i != count; i++) { |
| 165 | char c; |
| 166 | if (get_user(c, buf+i)) |
| 167 | return -EFAULT; |
| 168 | if (c == 'V') |
| 169 | expect_close = 42; |
| 170 | } |
| 171 | } |
| 172 | wdt_ping(); |
| 173 | } |
| 174 | return count; |
| 175 | } |
| 176 | |
| 177 | static int |
| 178 | wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, |
| 179 | unsigned long arg) |
| 180 | { |
| 181 | void __user *argp = (void __user *)arg; |
| 182 | int __user *p = argp; |
| 183 | int new_timeout; |
| 184 | static struct watchdog_info ident = { |
| 185 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, |
| 186 | .firmware_version = 1, |
| 187 | .identity = "W83697HF WDT", |
| 188 | }; |
| 189 | |
| 190 | switch (cmd) { |
| 191 | case WDIOC_GETSUPPORT: |
| 192 | if (copy_to_user(argp, &ident, sizeof(ident))) |
| 193 | return -EFAULT; |
| 194 | break; |
| 195 | |
| 196 | case WDIOC_GETSTATUS: |
| 197 | case WDIOC_GETBOOTSTATUS: |
| 198 | return put_user(0, p); |
| 199 | |
| 200 | case WDIOC_KEEPALIVE: |
| 201 | wdt_ping(); |
| 202 | break; |
| 203 | |
| 204 | case WDIOC_SETTIMEOUT: |
| 205 | if (get_user(new_timeout, p)) |
| 206 | return -EFAULT; |
| 207 | if (wdt_set_heartbeat(new_timeout)) |
| 208 | return -EINVAL; |
| 209 | wdt_ping(); |
| 210 | /* Fall */ |
| 211 | |
| 212 | case WDIOC_GETTIMEOUT: |
| 213 | return put_user(timeout, p); |
| 214 | |
| 215 | case WDIOC_SETOPTIONS: |
| 216 | { |
| 217 | int options, retval = -EINVAL; |
| 218 | |
| 219 | if (get_user(options, p)) |
| 220 | return -EFAULT; |
| 221 | |
| 222 | if (options & WDIOS_DISABLECARD) { |
| 223 | wdt_disable(); |
| 224 | retval = 0; |
| 225 | } |
| 226 | |
| 227 | if (options & WDIOS_ENABLECARD) { |
| 228 | wdt_ping(); |
| 229 | retval = 0; |
| 230 | } |
| 231 | |
| 232 | return retval; |
| 233 | } |
| 234 | |
| 235 | default: |
Wim Van Sebroeck | 196f29c | 2006-09-13 21:27:29 +0200 | [diff] [blame^] | 236 | return -ENOTTY; |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 237 | } |
| 238 | return 0; |
| 239 | } |
| 240 | |
| 241 | static int |
| 242 | wdt_open(struct inode *inode, struct file *file) |
| 243 | { |
| 244 | if (test_and_set_bit(0, &wdt_is_open)) |
| 245 | return -EBUSY; |
| 246 | /* |
| 247 | * Activate |
| 248 | */ |
| 249 | |
| 250 | wdt_ping(); |
| 251 | return nonseekable_open(inode, file); |
| 252 | } |
| 253 | |
| 254 | static int |
| 255 | wdt_close(struct inode *inode, struct file *file) |
| 256 | { |
| 257 | if (expect_close == 42) { |
| 258 | wdt_disable(); |
| 259 | } else { |
| 260 | printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n"); |
| 261 | wdt_ping(); |
| 262 | } |
| 263 | expect_close = 0; |
| 264 | clear_bit(0, &wdt_is_open); |
| 265 | return 0; |
| 266 | } |
| 267 | |
| 268 | /* |
| 269 | * Notifier for system down |
| 270 | */ |
| 271 | |
| 272 | static int |
| 273 | wdt_notify_sys(struct notifier_block *this, unsigned long code, |
| 274 | void *unused) |
| 275 | { |
| 276 | if (code == SYS_DOWN || code == SYS_HALT) { |
| 277 | /* Turn the WDT off */ |
| 278 | wdt_disable(); |
| 279 | } |
| 280 | return NOTIFY_DONE; |
| 281 | } |
| 282 | |
| 283 | /* |
| 284 | * Kernel Interfaces |
| 285 | */ |
| 286 | |
| 287 | static struct file_operations wdt_fops = { |
| 288 | .owner = THIS_MODULE, |
| 289 | .llseek = no_llseek, |
| 290 | .write = wdt_write, |
| 291 | .ioctl = wdt_ioctl, |
| 292 | .open = wdt_open, |
| 293 | .release = wdt_close, |
| 294 | }; |
| 295 | |
| 296 | static struct miscdevice wdt_miscdev = { |
| 297 | .minor = WATCHDOG_MINOR, |
| 298 | .name = "watchdog", |
| 299 | .fops = &wdt_fops, |
| 300 | }; |
| 301 | |
| 302 | /* |
| 303 | * The WDT needs to learn about soft shutdowns in order to |
| 304 | * turn the timebomb registers off. |
| 305 | */ |
| 306 | |
| 307 | static struct notifier_block wdt_notifier = { |
| 308 | .notifier_call = wdt_notify_sys, |
| 309 | }; |
| 310 | |
| 311 | static int __init |
| 312 | wdt_init(void) |
| 313 | { |
| 314 | int ret; |
| 315 | |
Wim Van Sebroeck | ab9d441 | 2006-09-02 18:50:20 +0200 | [diff] [blame] | 316 | spin_lock_init(&io_lock); |
| 317 | |
Marcus Junker | f9a8c89 | 2006-08-24 17:11:50 +0200 | [diff] [blame] | 318 | printk(KERN_INFO "WDT driver for the Winbond(TM) W83697HF Super I/O chip initialising.\n"); |
| 319 | |
| 320 | if (wdt_set_heartbeat(timeout)) { |
| 321 | wdt_set_heartbeat(WATCHDOG_TIMEOUT); |
| 322 | printk (KERN_INFO PFX "timeout value must be 1<=timeout<=63, using %d\n", |
| 323 | WATCHDOG_TIMEOUT); |
| 324 | } |
| 325 | |
| 326 | if (!request_region(wdt_io, 1, WATCHDOG_NAME)) { |
| 327 | printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", |
| 328 | wdt_io); |
| 329 | ret = -EIO; |
| 330 | goto out; |
| 331 | } |
| 332 | |
| 333 | w83697hf_init(); |
| 334 | |
| 335 | ret = register_reboot_notifier(&wdt_notifier); |
| 336 | if (ret != 0) { |
| 337 | printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", |
| 338 | ret); |
| 339 | goto unreg_regions; |
| 340 | } |
| 341 | |
| 342 | ret = misc_register(&wdt_miscdev); |
| 343 | if (ret != 0) { |
| 344 | printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", |
| 345 | WATCHDOG_MINOR, ret); |
| 346 | goto unreg_reboot; |
| 347 | } |
| 348 | |
| 349 | printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", |
| 350 | timeout, nowayout); |
| 351 | |
| 352 | out: |
| 353 | return ret; |
| 354 | unreg_reboot: |
| 355 | unregister_reboot_notifier(&wdt_notifier); |
| 356 | unreg_regions: |
| 357 | release_region(wdt_io, 1); |
| 358 | goto out; |
| 359 | } |
| 360 | |
| 361 | static void __exit |
| 362 | wdt_exit(void) |
| 363 | { |
| 364 | misc_deregister(&wdt_miscdev); |
| 365 | unregister_reboot_notifier(&wdt_notifier); |
| 366 | release_region(wdt_io,1); |
| 367 | } |
| 368 | |
| 369 | module_init(wdt_init); |
| 370 | module_exit(wdt_exit); |
| 371 | |
| 372 | MODULE_LICENSE("GPL"); |
| 373 | MODULE_AUTHOR("Marcus Junker <junker@anduras.de>"); |
| 374 | MODULE_DESCRIPTION("w83697hf WDT driver"); |
| 375 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |