Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 1 | /* |
| 2 | * w83697ug/uf WDT driver |
| 3 | * |
| 4 | * (c) Copyright 2008 Flemming Fransen <ff@nrvissing.net> |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame^] | 5 | * reused original code to support w83697ug/uf. |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 6 | * |
| 7 | * Based on w83627hf_wdt.c which is based on advantechwdt.c |
| 8 | * which is based on wdt.c. |
| 9 | * Original copyright messages: |
| 10 | * |
| 11 | * (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com> |
| 12 | * added support for W83627THF. |
| 13 | * |
| 14 | * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com> |
| 15 | * |
| 16 | * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl> |
| 17 | * |
| 18 | * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. |
| 19 | * http://www.redhat.com |
| 20 | * |
| 21 | * This program is free software; you can redistribute it and/or |
| 22 | * modify it under the terms of the GNU General Public License |
| 23 | * as published by the Free Software Foundation; either version |
| 24 | * 2 of the License, or (at your option) any later version. |
| 25 | * |
| 26 | * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide |
| 27 | * warranty for any of this software. This material is provided |
| 28 | * "AS-IS" and at no charge. |
| 29 | * |
| 30 | * (c) Copyright 1995 Alan Cox <alan@redhat.com> |
| 31 | */ |
| 32 | |
| 33 | #include <linux/module.h> |
| 34 | #include <linux/moduleparam.h> |
| 35 | #include <linux/types.h> |
| 36 | #include <linux/miscdevice.h> |
| 37 | #include <linux/watchdog.h> |
| 38 | #include <linux/fs.h> |
| 39 | #include <linux/ioport.h> |
| 40 | #include <linux/notifier.h> |
| 41 | #include <linux/reboot.h> |
| 42 | #include <linux/init.h> |
| 43 | #include <linux/spinlock.h> |
| 44 | #include <linux/io.h> |
| 45 | #include <linux/uaccess.h> |
| 46 | |
| 47 | #include <asm/system.h> |
| 48 | |
| 49 | #define WATCHDOG_NAME "w83697ug/uf WDT" |
| 50 | #define PFX WATCHDOG_NAME ": " |
| 51 | #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ |
| 52 | |
| 53 | static unsigned long wdt_is_open; |
| 54 | static char expect_close; |
| 55 | static DEFINE_SPINLOCK(io_lock); |
| 56 | |
| 57 | static int wdt_io = 0x2e; |
| 58 | module_param(wdt_io, int, 0); |
| 59 | MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)"); |
| 60 | |
| 61 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ |
| 62 | module_param(timeout, int, 0); |
| 63 | MODULE_PARM_DESC(timeout, |
| 64 | "Watchdog timeout in seconds. 1<= timeout <=255 (default=" |
| 65 | __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); |
| 66 | |
| 67 | static int nowayout = WATCHDOG_NOWAYOUT; |
| 68 | module_param(nowayout, int, 0); |
| 69 | MODULE_PARM_DESC(nowayout, |
| 70 | "Watchdog cannot be stopped once started (default=" |
| 71 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
| 72 | |
| 73 | /* |
| 74 | * Kernel methods. |
| 75 | */ |
| 76 | |
| 77 | #define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */ |
| 78 | #define WDT_EFIR (wdt_io+0) /* Extended Function Index Register |
| 79 | (same as EFER) */ |
| 80 | #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */ |
| 81 | |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 82 | static int w83697ug_select_wd_register(void) |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 83 | { |
| 84 | unsigned char c; |
| 85 | unsigned char version; |
| 86 | |
| 87 | outb_p(0x87, WDT_EFER); /* Enter extended function mode */ |
| 88 | outb_p(0x87, WDT_EFER); /* Again according to manual */ |
| 89 | |
| 90 | outb(0x20, WDT_EFER); /* check chip version */ |
| 91 | version = inb(WDT_EFDR); |
| 92 | |
| 93 | if (version == 0x68) { /* W83697UG */ |
| 94 | printk(KERN_INFO PFX "Watchdog chip version 0x%02x = " |
| 95 | "W83697UG/UF found at 0x%04x\n", version, wdt_io); |
| 96 | |
| 97 | outb_p(0x2b, WDT_EFER); |
| 98 | c = inb_p(WDT_EFDR); /* select WDT0 */ |
| 99 | c &= ~0x04; |
| 100 | outb_p(0x2b, WDT_EFER); |
| 101 | outb_p(c, WDT_EFDR); /* set pin118 to WDT0 */ |
| 102 | |
| 103 | } else { |
| 104 | printk(KERN_ERR PFX "No W83697UG/UF could be found\n"); |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 105 | return -ENODEV; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 106 | } |
| 107 | |
| 108 | outb_p(0x07, WDT_EFER); /* point to logical device number reg */ |
| 109 | outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */ |
| 110 | outb_p(0x30, WDT_EFER); /* select CR30 */ |
| 111 | c = inb_p(WDT_EFDR); |
| 112 | outb_p(c || 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */ |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 113 | |
| 114 | return 0; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 115 | } |
| 116 | |
| 117 | static void w83697ug_unselect_wd_register(void) |
| 118 | { |
| 119 | outb_p(0xAA, WDT_EFER); /* Leave extended function mode */ |
| 120 | } |
| 121 | |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 122 | static int w83697ug_init(void) |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 123 | { |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 124 | int ret; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 125 | unsigned char t; |
| 126 | |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 127 | ret = w83697ug_select_wd_register(); |
| 128 | if (ret != 0) |
| 129 | return ret; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 130 | |
| 131 | outb_p(0xF6, WDT_EFER); /* Select CRF6 */ |
| 132 | t = inb_p(WDT_EFDR); /* read CRF6 */ |
| 133 | if (t != 0) { |
| 134 | printk(KERN_INFO PFX "Watchdog already running." |
| 135 | " Resetting timeout to %d sec\n", timeout); |
| 136 | outb_p(timeout, WDT_EFDR); /* Write back to CRF6 */ |
| 137 | } |
| 138 | outb_p(0xF5, WDT_EFER); /* Select CRF5 */ |
| 139 | t = inb_p(WDT_EFDR); /* read CRF5 */ |
| 140 | t &= ~0x0C; /* set second mode & |
| 141 | disable keyboard turning off watchdog */ |
| 142 | outb_p(t, WDT_EFDR); /* Write back to CRF5 */ |
| 143 | |
| 144 | w83697ug_unselect_wd_register(); |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 145 | return 0; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 146 | } |
| 147 | |
| 148 | static void wdt_ctrl(int timeout) |
| 149 | { |
| 150 | spin_lock(&io_lock); |
| 151 | |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 152 | if (w83697ug_select_wd_register() < 0) |
| 153 | return; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 154 | |
| 155 | outb_p(0xF4, WDT_EFER); /* Select CRF4 */ |
| 156 | outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */ |
| 157 | |
| 158 | w83697ug_unselect_wd_register(); |
| 159 | |
| 160 | spin_unlock(&io_lock); |
| 161 | } |
| 162 | |
| 163 | static int wdt_ping(void) |
| 164 | { |
| 165 | wdt_ctrl(timeout); |
| 166 | return 0; |
| 167 | } |
| 168 | |
| 169 | static int wdt_disable(void) |
| 170 | { |
| 171 | wdt_ctrl(0); |
| 172 | return 0; |
| 173 | } |
| 174 | |
| 175 | static int wdt_set_heartbeat(int t) |
| 176 | { |
| 177 | if (t < 1 || t > 255) |
| 178 | return -EINVAL; |
| 179 | |
| 180 | timeout = t; |
| 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | static ssize_t wdt_write(struct file *file, const char __user *buf, |
| 185 | size_t count, loff_t *ppos) |
| 186 | { |
| 187 | if (count) { |
| 188 | if (!nowayout) { |
| 189 | size_t i; |
| 190 | |
| 191 | expect_close = 0; |
| 192 | |
| 193 | for (i = 0; i != count; i++) { |
| 194 | char c; |
| 195 | if (get_user(c, buf + i)) |
| 196 | return -EFAULT; |
| 197 | if (c == 'V') |
| 198 | expect_close = 42; |
| 199 | } |
| 200 | } |
| 201 | wdt_ping(); |
| 202 | } |
| 203 | return count; |
| 204 | } |
| 205 | |
| 206 | static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 207 | { |
| 208 | void __user *argp = (void __user *)arg; |
| 209 | int __user *p = argp; |
| 210 | int new_timeout; |
| 211 | static const struct watchdog_info ident = { |
| 212 | .options = WDIOF_KEEPALIVEPING | |
| 213 | WDIOF_SETTIMEOUT | |
| 214 | WDIOF_MAGICCLOSE, |
| 215 | .firmware_version = 1, |
| 216 | .identity = "W83697UG WDT", |
| 217 | }; |
| 218 | |
| 219 | switch (cmd) { |
| 220 | case WDIOC_GETSUPPORT: |
| 221 | if (copy_to_user(argp, &ident, sizeof(ident))) |
| 222 | return -EFAULT; |
| 223 | break; |
| 224 | |
| 225 | case WDIOC_GETSTATUS: |
| 226 | case WDIOC_GETBOOTSTATUS: |
| 227 | return put_user(0, p); |
| 228 | |
| 229 | case WDIOC_SETOPTIONS: |
| 230 | { |
| 231 | int options, retval = -EINVAL; |
| 232 | |
| 233 | if (get_user(options, p)) |
| 234 | return -EFAULT; |
| 235 | |
| 236 | if (options & WDIOS_DISABLECARD) { |
| 237 | wdt_disable(); |
| 238 | retval = 0; |
| 239 | } |
| 240 | |
| 241 | if (options & WDIOS_ENABLECARD) { |
| 242 | wdt_ping(); |
| 243 | retval = 0; |
| 244 | } |
| 245 | |
| 246 | return retval; |
| 247 | } |
| 248 | |
| 249 | case WDIOC_KEEPALIVE: |
| 250 | wdt_ping(); |
| 251 | break; |
| 252 | |
| 253 | case WDIOC_SETTIMEOUT: |
| 254 | if (get_user(new_timeout, p)) |
| 255 | return -EFAULT; |
| 256 | if (wdt_set_heartbeat(new_timeout)) |
| 257 | return -EINVAL; |
| 258 | wdt_ping(); |
| 259 | /* Fall */ |
| 260 | |
| 261 | case WDIOC_GETTIMEOUT: |
| 262 | return put_user(timeout, p); |
| 263 | |
| 264 | default: |
| 265 | return -ENOTTY; |
| 266 | } |
| 267 | return 0; |
| 268 | } |
| 269 | |
| 270 | static int wdt_open(struct inode *inode, struct file *file) |
| 271 | { |
| 272 | if (test_and_set_bit(0, &wdt_is_open)) |
| 273 | return -EBUSY; |
| 274 | /* |
| 275 | * Activate |
| 276 | */ |
| 277 | |
| 278 | wdt_ping(); |
| 279 | return nonseekable_open(inode, file); |
| 280 | } |
| 281 | |
| 282 | static int wdt_close(struct inode *inode, struct file *file) |
| 283 | { |
| 284 | if (expect_close == 42) |
| 285 | wdt_disable(); |
| 286 | else { |
| 287 | printk(KERN_CRIT PFX |
| 288 | "Unexpected close, not stopping watchdog!\n"); |
| 289 | wdt_ping(); |
| 290 | } |
| 291 | expect_close = 0; |
| 292 | clear_bit(0, &wdt_is_open); |
| 293 | return 0; |
| 294 | } |
| 295 | |
| 296 | /* |
| 297 | * Notifier for system down |
| 298 | */ |
| 299 | |
| 300 | static int wdt_notify_sys(struct notifier_block *this, unsigned long code, |
| 301 | void *unused) |
| 302 | { |
| 303 | if (code == SYS_DOWN || code == SYS_HALT) |
| 304 | wdt_disable(); /* Turn the WDT off */ |
| 305 | |
| 306 | return NOTIFY_DONE; |
| 307 | } |
| 308 | |
| 309 | /* |
| 310 | * Kernel Interfaces |
| 311 | */ |
| 312 | |
| 313 | static const struct file_operations wdt_fops = { |
| 314 | .owner = THIS_MODULE, |
| 315 | .llseek = no_llseek, |
| 316 | .write = wdt_write, |
| 317 | .unlocked_ioctl = wdt_ioctl, |
| 318 | .open = wdt_open, |
| 319 | .release = wdt_close, |
| 320 | }; |
| 321 | |
| 322 | static struct miscdevice wdt_miscdev = { |
| 323 | .minor = WATCHDOG_MINOR, |
| 324 | .name = "watchdog", |
| 325 | .fops = &wdt_fops, |
| 326 | }; |
| 327 | |
| 328 | /* |
| 329 | * The WDT needs to learn about soft shutdowns in order to |
| 330 | * turn the timebomb registers off. |
| 331 | */ |
| 332 | |
| 333 | static struct notifier_block wdt_notifier = { |
| 334 | .notifier_call = wdt_notify_sys, |
| 335 | }; |
| 336 | |
| 337 | static int __init wdt_init(void) |
| 338 | { |
| 339 | int ret; |
| 340 | |
| 341 | printk(KERN_INFO "WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising.\n"); |
| 342 | |
| 343 | if (wdt_set_heartbeat(timeout)) { |
| 344 | wdt_set_heartbeat(WATCHDOG_TIMEOUT); |
| 345 | printk(KERN_INFO PFX |
| 346 | "timeout value must be 1<=timeout<=255, using %d\n", |
| 347 | WATCHDOG_TIMEOUT); |
| 348 | } |
| 349 | |
| 350 | if (!request_region(wdt_io, 1, WATCHDOG_NAME)) { |
| 351 | printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", |
| 352 | wdt_io); |
| 353 | ret = -EIO; |
| 354 | goto out; |
| 355 | } |
| 356 | |
Eric Lammerts | 63bad14 | 2009-02-03 17:45:56 -0500 | [diff] [blame] | 357 | ret = w83697ug_init(); |
| 358 | if (ret != 0) |
| 359 | goto unreg_regions; |
Flemming Frandsen | 7d8b090 | 2008-04-17 11:29:54 +0200 | [diff] [blame] | 360 | |
| 361 | ret = register_reboot_notifier(&wdt_notifier); |
| 362 | if (ret != 0) { |
| 363 | printk(KERN_ERR PFX |
| 364 | "cannot register reboot notifier (err=%d)\n", ret); |
| 365 | goto unreg_regions; |
| 366 | } |
| 367 | |
| 368 | ret = misc_register(&wdt_miscdev); |
| 369 | if (ret != 0) { |
| 370 | printk(KERN_ERR PFX |
| 371 | "cannot register miscdev on minor=%d (err=%d)\n", |
| 372 | WATCHDOG_MINOR, ret); |
| 373 | goto unreg_reboot; |
| 374 | } |
| 375 | |
| 376 | printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", |
| 377 | timeout, nowayout); |
| 378 | |
| 379 | out: |
| 380 | return ret; |
| 381 | unreg_reboot: |
| 382 | unregister_reboot_notifier(&wdt_notifier); |
| 383 | unreg_regions: |
| 384 | release_region(wdt_io, 1); |
| 385 | goto out; |
| 386 | } |
| 387 | |
| 388 | static void __exit wdt_exit(void) |
| 389 | { |
| 390 | misc_deregister(&wdt_miscdev); |
| 391 | unregister_reboot_notifier(&wdt_notifier); |
| 392 | release_region(wdt_io, 1); |
| 393 | } |
| 394 | |
| 395 | module_init(wdt_init); |
| 396 | module_exit(wdt_exit); |
| 397 | |
| 398 | MODULE_LICENSE("GPL"); |
| 399 | MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>"); |
| 400 | MODULE_DESCRIPTION("w83697ug/uf WDT driver"); |
| 401 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |