1 /*
2 * PC Watchdog Driver
3 * by Ken Hollis (khollis@bitgate.com)
4 *
5 * Permission granted from Simon Machell (73244.1270@compuserve.com)
6 * Written for the Linux Kernel, and GPLed by Ken Hollis
7 *
8 * 960107 Added request_region routines, modulized the whole thing.
9 * 960108 Fixed end-of-file pointer (Thanks to Dan Hollis), added
10 * WD_TIMEOUT define.
11 * 960216 Added eof marker on the file, and changed verbose messages.
12 * 960716 Made functional and cosmetic changes to the source for
13 * inclusion in Linux 2.0.x kernels, thanks to Alan Cox.
14 * 960717 Removed read/seek routines, replaced with ioctl. Also, added
15 * check_region command due to Alan's suggestion.
16 * 960821 Made changes to compile in newer 2.0.x kernels. Added
17 * "cold reboot sense" entry.
18 * 960825 Made a few changes to code, deleted some defines and made
19 * typedefs to replace them. Made heartbeat reset only available
20 * via ioctl, and removed the write routine.
21 * 960828 Added new items for PC Watchdog Rev.C card.
22 * 960829 Changed around all of the IOCTLs, added new features,
23 * added watchdog disable/re-enable routines. Added firmware
24 * version reporting. Added read routine for temperature.
25 * Removed some extra defines, added an autodetect Revision
26 * routine.
27 * 961006 Revised some documentation, fixed some cosmetic bugs. Made
28 * drivers to panic the system if it's overheating at bootup.
29 * 961118 Changed some verbiage on some of the output, tidied up
30 * code bits, and added compatibility to 2.1.x.
31 * 970912 Enabled board on open and disable on close.
32 * 971107 Took account of recent VFS changes (broke read).
33 * 971210 Disable board on initialisation in case board already ticking.
34 * 971222 Changed open/close for temperature handling
35 * Michael Meskes <meskes@debian.org>.
36 * 980112 Used minor numbers from include/linux/miscdevice.h
37 * 990403 Clear reset status after reading control status register in
38 * pcwd_showprevstate(). [Marc Boucher <marc@mbsi.ca>]
39 * 990605 Made changes to code to support Firmware 1.22a, added
40 * fairly useless proc entry.
41 * 990610 removed said useless proc code for the merge <alan>
42 * 000403 Removed last traces of proc code. <davej>
43 * 011214 Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT <Matt_Domsch@dell.com>
44 * Added timeout module option to override default
45 */
46
47 /*
48 * A bells and whistles driver is available from http://www.pcwd.de/
49 * More info available at http://www.berkprod.com/ or http://www.pcwatchdog.com/
50 */
51
52 #include <linux/config.h> /* For CONFIG_WATCHDOG_NOWAYOUT/... */
53 #include <linux/module.h> /* For module specific items */
54 #include <linux/moduleparam.h> /* For new moduleparam's */
55 #include <linux/types.h> /* For standard types (like size_t) */
56 #include <linux/errno.h> /* For the -ENODEV/... values */
57 #include <linux/kernel.h> /* For printk/panic/... */
58 #include <linux/delay.h> /* For mdelay function */
59 #include <linux/timer.h> /* For timer related operations */
60 #include <linux/jiffies.h> /* For jiffies stuff */
61 #include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
62 #include <linux/watchdog.h> /* For the watchdog specific items */
63 #include <linux/notifier.h> /* For notifier support */
64 #include <linux/reboot.h> /* For reboot_notifier stuff */
65 #include <linux/init.h> /* For __init/__exit/... */
66 #include <linux/fs.h> /* For file operations */
67 #include <linux/ioport.h> /* For io-port access */
68 #include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
69
70 #include <asm/uaccess.h> /* For copy_to_user/put_user/... */
71 #include <asm/io.h> /* For inb/outb/... */
72
73 /* Module and version information */
74 #define WATCHDOG_VERSION "1.17"
75 #define WATCHDOG_DATE "12 Feb 2006"
76 #define WATCHDOG_DRIVER_NAME "ISA-PC Watchdog"
77 #define WATCHDOG_NAME "pcwd"
78 #define PFX WATCHDOG_NAME ": "
79 #define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION " (" WATCHDOG_DATE ")\n"
80 #define WD_VER WATCHDOG_VERSION " (" WATCHDOG_DATE ")"
81
82 /*
83 * It should be noted that PCWD_REVISION_B was removed because A and B
84 * are essentially the same types of card, with the exception that B
85 * has temperature reporting. Since I didn't receive a Rev.B card,
86 * the Rev.B card is not supported. (It's a good thing too, as they
87 * are no longer in production.)
88 */
89 #define PCWD_REVISION_A 1
90 #define PCWD_REVISION_C 2
91
92 /*
93 * These are the defines that describe the control status bits for the
94 * PCI-PC Watchdog card.
95 */
96 /* Port 1 : Control Status #1 for the PC Watchdog card, revision A. */
97 #define WD_WDRST 0x01 /* Previously reset state */
98 #define WD_T110 0x02 /* Temperature overheat sense */
99 #define WD_HRTBT 0x04 /* Heartbeat sense */
100 #define WD_RLY2 0x08 /* External relay triggered */
101 #define WD_SRLY2 0x80 /* Software external relay triggered */
102 /* Port 1 : Control Status #1 for the PC Watchdog card, revision C. */
103 #define WD_REVC_WTRP 0x01 /* Watchdog Trip status */
104 #define WD_REVC_HRBT 0x02 /* Watchdog Heartbeat */
105 #define WD_REVC_TTRP 0x04 /* Temperature Trip status */
106 #define WD_REVC_RL2A 0x08 /* Relay 2 activated by on-board processor */
107 #define WD_REVC_RL1A 0x10 /* Relay 1 active */
108 #define WD_REVC_R2DS 0x40 /* Relay 2 disable */
109 #define WD_REVC_RLY2 0x80 /* Relay 2 activated? */
110 /* Port 2 : Control Status #2 */
111 #define WD_WDIS 0x10 /* Watchdog Disabled */
112 #define WD_ENTP 0x20 /* Watchdog Enable Temperature Trip */
113 #define WD_SSEL 0x40 /* Watchdog Switch Select (1:SW1 <-> 0:SW2) */
114 #define WD_WCMD 0x80 /* Watchdog Command Mode */
115
116 /* max. time we give an ISA watchdog card to process a command */
117 /* 500ms for each 4 bit response (according to spec.) */
118 #define ISA_COMMAND_TIMEOUT 1000
119
120 /* Watchdog's internal commands */
121 #define CMD_ISA_IDLE 0x00
122 #define CMD_ISA_VERSION_INTEGER 0x01
123 #define CMD_ISA_VERSION_TENTH 0x02
124 #define CMD_ISA_VERSION_HUNDRETH 0x03
125 #define CMD_ISA_VERSION_MINOR 0x04
126 #define CMD_ISA_SWITCH_SETTINGS 0x05
127 #define CMD_ISA_RESET_PC 0x06
128 #define CMD_ISA_ARM_0 0x07
129 #define CMD_ISA_ARM_30 0x08
130 #define CMD_ISA_ARM_60 0x09
131 #define CMD_ISA_DELAY_TIME_2SECS 0x0A
132 #define CMD_ISA_DELAY_TIME_4SECS 0x0B
133 #define CMD_ISA_DELAY_TIME_8SECS 0x0C
134 #define CMD_ISA_RESET_RELAYS 0x0D
135
136 /*
137 * We are using an kernel timer to do the pinging of the watchdog
138 * every ~500ms. We try to set the internal heartbeat of the
139 * watchdog to 2 ms.
140 */
141
142 #define WDT_INTERVAL (HZ/2+1)
143
144 /* We can only use 1 card due to the /dev/watchdog restriction */
145 static int cards_found;
146
147 /* internal variables */
148 static atomic_t open_allowed = ATOMIC_INIT(1);
149 static char expect_close;
150 static int temp_panic;
151 static struct { /* this is private data for each ISA-PC watchdog card */
152 char fw_ver_str[6]; /* The cards firmware version */
153 int revision; /* The card's revision */
154 int supports_temp; /* Wether or not the card has a temperature device */
155 int command_mode; /* Wether or not the card is in command mode */
156 int boot_status; /* The card's boot status */
157 int io_addr; /* The cards I/O address */
158 spinlock_t io_lock; /* the lock for io operations */
159 struct timer_list timer; /* The timer that pings the watchdog */
160 unsigned long next_heartbeat; /* the next_heartbeat for the timer */
161 } pcwd_private;
162
163 /* module parameters */
164 #define QUIET 0 /* Default */
165 #define VERBOSE 1 /* Verbose */
166 #define DEBUG 2 /* print fancy stuff too */
167 static int debug = QUIET;
168 module_param(debug, int, 0);
169 MODULE_PARM_DESC(debug, "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
170
171 #define WATCHDOG_HEARTBEAT 60 /* 60 sec default heartbeat */
172 static int heartbeat = WATCHDOG_HEARTBEAT;
173 module_param(heartbeat, int, 0);
174 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2<=heartbeat<=7200, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
175
176 static int nowayout = WATCHDOG_NOWAYOUT;
177 module_param(nowayout, int, 0);
178 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
179
180 /*
181 * Internal functions
182 */
183
184 static int send_isa_command(int cmd)
185 {
186 int i;
187 int control_status;
188 int port0, last_port0; /* Double read for stabilising */
189
190 if (debug >= DEBUG)
191 printk(KERN_DEBUG PFX "sending following data cmd=0x%02x\n",
192 cmd);
193
194 /* The WCMD bit must be 1 and the command is only 4 bits in size */
195 control_status = (cmd & 0x0F) | WD_WCMD;
196 outb_p(control_status, pcwd_private.io_addr + 2);
197 udelay(ISA_COMMAND_TIMEOUT);
198
199 port0 = inb_p(pcwd_private.io_addr);
200 for (i = 0; i < 25; ++i) {
201 last_port0 = port0;
202 port0 = inb_p(pcwd_private.io_addr);
203
204 if (port0 == last_port0)
205 break; /* Data is stable */
206
207 udelay (250);
208 }
209
210 if (debug >= DEBUG)
211 printk(KERN_DEBUG PFX "received following data for cmd=0x%02x: port0=0x%02x last_port0=0x%02x\n",
212 cmd, port0, last_port0);
213
214 return port0;
215 }
216
217 static int set_command_mode(void)
218 {
219 int i, found=0, count=0;
220
221 /* Set the card into command mode */
222 spin_lock(&pcwd_private.io_lock);
223 while ((!found) && (count < 3)) {
224 i = send_isa_command(CMD_ISA_IDLE);
225
226 if (i == 0x00)
227 found = 1;
228 else if (i == 0xF3) {
229 /* Card does not like what we've done to it */
230 outb_p(0x00, pcwd_private.io_addr + 2);
231 udelay(1200); /* Spec says wait 1ms */
232 outb_p(0x00, pcwd_private.io_addr + 2);
233 udelay(ISA_COMMAND_TIMEOUT);
234 }
235 count++;
236 }
237 spin_unlock(&pcwd_private.io_lock);
238 pcwd_private.command_mode = found;
239
240 if (debug >= DEBUG)
241 printk(KERN_DEBUG PFX "command_mode=%d\n",
242 pcwd_private.command_mode);
243
244 return(found);
245 }
246
247 static void unset_command_mode(void)
248 {
249 /* Set the card into normal mode */
250 spin_lock(&pcwd_private.io_lock);
251 outb_p(0x00, pcwd_private.io_addr + 2);
252 udelay(ISA_COMMAND_TIMEOUT);
253 spin_unlock(&pcwd_private.io_lock);
254
255 pcwd_private.command_mode = 0;
256
257 if (debug >= DEBUG)
258 printk(KERN_DEBUG PFX "command_mode=%d\n",
259 pcwd_private.command_mode);
260 }
261
262 static inline void pcwd_check_temperature_support(void)
263 {
264 if (inb(pcwd_private.io_addr) != 0xF0)
265 pcwd_private.supports_temp = 1;
266 }
267
268 static inline void pcwd_get_firmware(void)
269 {
270 int one, ten, hund, minor;
271
272 strcpy(pcwd_private.fw_ver_str, "ERROR");
273
274 if (set_command_mode()) {
275 one = send_isa_command(CMD_ISA_VERSION_INTEGER);
276 ten = send_isa_command(CMD_ISA_VERSION_TENTH);
277 hund = send_isa_command(CMD_ISA_VERSION_HUNDRETH);
278 minor = send_isa_command(CMD_ISA_VERSION_MINOR);
279 sprintf(pcwd_private.fw_ver_str, "%c.%c%c%c", one, ten, hund, minor);
280 }
281 unset_command_mode();
282
283 return;
284 }
285
286 static inline int pcwd_get_option_switches(void)
287 {
288 int option_switches=0;
289
290 if (set_command_mode()) {
291 /* Get switch settings */
292 option_switches = send_isa_command(CMD_ISA_SWITCH_SETTINGS);
293 }
294
295 unset_command_mode();
296 return(option_switches);
297 }
298
299 static void pcwd_show_card_info(void)
300 {
301 int option_switches;
302
303 /* Get some extra info from the hardware (in command/debug/diag mode) */
304 if (pcwd_private.revision == PCWD_REVISION_A)
305 printk(KERN_INFO PFX "ISA-PC Watchdog (REV.A) detected at port 0x%04x\n", pcwd_private.io_addr);
306 else if (pcwd_private.revision == PCWD_REVISION_C) {
307 pcwd_get_firmware();
308 printk(KERN_INFO PFX "ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n",
309 pcwd_private.io_addr, pcwd_private.fw_ver_str);
310 option_switches = pcwd_get_option_switches();
311 printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
312 option_switches,
313 ((option_switches & 0x10) ? "ON" : "OFF"),
314 ((option_switches & 0x08) ? "ON" : "OFF"));
315
316 /* Reprogram internal heartbeat to 2 seconds */
317 if (set_command_mode()) {
318 send_isa_command(CMD_ISA_DELAY_TIME_2SECS);
319 unset_command_mode();
320 }
321 }
322
323 if (pcwd_private.supports_temp)
324 printk(KERN_INFO PFX "Temperature Option Detected\n");
325
326 if (pcwd_private.boot_status & WDIOF_CARDRESET)
327 printk(KERN_INFO PFX "Previous reboot was caused by the card\n");
328
329 if (pcwd_private.boot_status & WDIOF_OVERHEAT) {
330 printk(KERN_EMERG PFX "Card senses a CPU Overheat. Panicking!\n");
331 printk(KERN_EMERG PFX "CPU Overheat\n");
332 }
333
334 if (pcwd_private.boot_status == 0)
335 printk(KERN_INFO PFX "No previous trip detected - Cold boot or reset\n");
336 }
337
338 static void pcwd_timer_ping(unsigned long data)
339 {
340 int wdrst_stat;
341
342 /* If we got a heartbeat pulse within the WDT_INTERVAL
343 * we agree to ping the WDT */
344 if(time_before(jiffies, pcwd_private.next_heartbeat)) {
345 /* Ping the watchdog */
346 spin_lock(&pcwd_private.io_lock);
347 if (pcwd_private.revision == PCWD_REVISION_A) {
348 /* Rev A cards are reset by setting the WD_WDRST bit in register 1 */
349 wdrst_stat = inb_p(pcwd_private.io_addr);
350 wdrst_stat &= 0x0F;
351 wdrst_stat |= WD_WDRST;
352
353 outb_p(wdrst_stat, pcwd_private.io_addr + 1);
354 } else {
355 /* Re-trigger watchdog by writing to port 0 */
356 outb_p(0x00, pcwd_private.io_addr);
357 }
358
359 /* Re-set the timer interval */
360 mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
361
362 spin_unlock(&pcwd_private.io_lock);
363 } else {
364 printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
365 }
366 }
367
368 static int pcwd_start(void)
369 {
370 int stat_reg;
371
372 pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
373
374 /* Start the timer */
375 mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
376
377 /* Enable the port */
378 if (pcwd_private.revision == PCWD_REVISION_C) {
379 spin_lock(&pcwd_private.io_lock);
380 outb_p(0x00, pcwd_private.io_addr + 3);
381 udelay(ISA_COMMAND_TIMEOUT);
382 stat_reg = inb_p(pcwd_private.io_addr + 2);
383 spin_unlock(&pcwd_private.io_lock);
384 if (stat_reg & WD_WDIS) {
385 printk(KERN_INFO PFX "Could not start watchdog\n");
386 return -EIO;
387 }
388 }
389
390 if (debug >= VERBOSE)
391 printk(KERN_DEBUG PFX "Watchdog started\n");
392
393 return 0;
394 }
395
396 static int pcwd_stop(void)
397 {
398 int stat_reg;
399
400 /* Stop the timer */
401 del_timer(&pcwd_private.timer);
402
403 /* Disable the board */
404 if (pcwd_private.revision == PCWD_REVISION_C) {
405 spin_lock(&pcwd_private.io_lock);
406 outb_p(0xA5, pcwd_private.io_addr + 3);
407 udelay(ISA_COMMAND_TIMEOUT);
408 outb_p(0xA5, pcwd_private.io_addr + 3);
409 udelay(ISA_COMMAND_TIMEOUT);
410 stat_reg = inb_p(pcwd_private.io_addr + 2);
411 spin_unlock(&pcwd_private.io_lock);
412 if ((stat_reg & WD_WDIS) == 0) {
413 printk(KERN_INFO PFX "Could not stop watchdog\n");
414 return -EIO;
415 }
416 }
417
418 if (debug >= VERBOSE)
419 printk(KERN_DEBUG PFX "Watchdog stopped\n");
420
421 return 0;
422 }
423
424 static int pcwd_keepalive(void)
425 {
426 /* user land ping */
427 pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
428
429 if (debug >= DEBUG)
430 printk(KERN_DEBUG PFX "Watchdog keepalive signal send\n");
431
432 return 0;
433 }
434
435 static int pcwd_set_heartbeat(int t)
436 {
437 if ((t < 2) || (t > 7200)) /* arbitrary upper limit */
438 return -EINVAL;
439
440 heartbeat = t;
441
442 if (debug >= VERBOSE)
443 printk(KERN_DEBUG PFX "New heartbeat: %d\n",
444 heartbeat);
445
446 return 0;
447 }
448
449 static int pcwd_get_status(int *status)
450 {
451 int control_status;
452
453 *status=0;
454 spin_lock(&pcwd_private.io_lock);
455 if (pcwd_private.revision == PCWD_REVISION_A)
456 /* Rev A cards return status information from
457 * the base register, which is used for the
458 * temperature in other cards. */
459 control_status = inb(pcwd_private.io_addr);
460 else {
461 /* Rev C cards return card status in the base
462 * address + 1 register. And use different bits
463 * to indicate a card initiated reset, and an
464 * over-temperature condition. And the reboot
465 * status can be reset. */
466 control_status = inb(pcwd_private.io_addr + 1);
467 }
468 spin_unlock(&pcwd_private.io_lock);
469
470 if (pcwd_private.revision == PCWD_REVISION_A) {
471 if (control_status & WD_WDRST)
472 *status |= WDIOF_CARDRESET;
473
474 if (control_status & WD_T110) {
475 *status |= WDIOF_OVERHEAT;
476 if (temp_panic) {
477 printk (KERN_INFO PFX "Temperature overheat trip!\n");
478 kernel_power_off();
479 /* or should we just do a: panic(PFX "Temperature overheat trip!\n"); */
480 }
481 }
482 } else {
483 if (control_status & WD_REVC_WTRP)
484 *status |= WDIOF_CARDRESET;
485
486 if (control_status & WD_REVC_TTRP) {
487 *status |= WDIOF_OVERHEAT;
488 if (temp_panic) {
489 printk (KERN_INFO PFX "Temperature overheat trip!\n");
490 kernel_power_off();
491 /* or should we just do a: panic(PFX "Temperature overheat trip!\n"); */
492 }
493 }
494 }
495
496 return 0;
497 }
498
499 static int pcwd_clear_status(void)
500 {
501 int control_status;
502
503 if (pcwd_private.revision == PCWD_REVISION_C) {
504 spin_lock(&pcwd_private.io_lock);
505
506 if (debug >= VERBOSE)
507 printk(KERN_INFO PFX "clearing watchdog trip status\n");
508
509 control_status = inb_p(pcwd_private.io_addr + 1);
510
511 if (debug >= DEBUG) {
512 printk(KERN_DEBUG PFX "status was: 0x%02x\n", control_status);
513 printk(KERN_DEBUG PFX "sending: 0x%02x\n",
514 (control_status & WD_REVC_R2DS));
515 }
516
517 /* clear reset status & Keep Relay 2 disable state as it is */
518 outb_p((control_status & WD_REVC_R2DS), pcwd_private.io_addr + 1);
519
520 spin_unlock(&pcwd_private.io_lock);
521 }
522 return 0;
523 }
524
525 static int pcwd_get_temperature(int *temperature)
526 {
527 /* check that port 0 gives temperature info and no command results */
528 if (pcwd_private.command_mode)
529 return -1;
530
531 *temperature = 0;
532 if (!pcwd_private.supports_temp)
533 return -ENODEV;
534
535 /*
536 * Convert celsius to fahrenheit, since this was
537 * the decided 'standard' for this return value.
538 */
539 spin_lock(&pcwd_private.io_lock);
540 *temperature = ((inb(pcwd_private.io_addr)) * 9 / 5) + 32;
541 spin_unlock(&pcwd_private.io_lock);
542
543 if (debug >= DEBUG) {
544 printk(KERN_DEBUG PFX "temperature is: %d F\n",
545 *temperature);
546 }
547
548 return 0;
549 }
550
551 /*
552 * /dev/watchdog handling
553 */
554
555 static int pcwd_ioctl(struct inode *inode, struct file *file,
556 unsigned int cmd, unsigned long arg)
557 {
558 int rv;
559 int status;
560 int temperature;
561 int new_heartbeat;
562 int __user *argp = (int __user *)arg;
563 static struct watchdog_info ident = {
564 .options = WDIOF_OVERHEAT |
565 WDIOF_CARDRESET |
566 WDIOF_KEEPALIVEPING |
567 WDIOF_SETTIMEOUT |
568 WDIOF_MAGICCLOSE,
569 .firmware_version = 1,
570 .identity = "PCWD",
571 };
572
573 switch(cmd) {
574 default:
575 return -ENOIOCTLCMD;
576
577 case WDIOC_GETSUPPORT:
578 if(copy_to_user(argp, &ident, sizeof(ident)))
579 return -EFAULT;
580 return 0;
581
582 case WDIOC_GETSTATUS:
583 pcwd_get_status(&status);
584 return put_user(status, argp);
585
586 case WDIOC_GETBOOTSTATUS:
587 return put_user(pcwd_private.boot_status, argp);
588
589 case WDIOC_GETTEMP:
590 if (pcwd_get_temperature(&temperature))
591 return -EFAULT;
592
593 return put_user(temperature, argp);
594
595 case WDIOC_SETOPTIONS:
596 if (pcwd_private.revision == PCWD_REVISION_C)
597 {
598 if(copy_from_user(&rv, argp, sizeof(int)))
599 return -EFAULT;
600
601 if (rv & WDIOS_DISABLECARD)
602 {
603 return pcwd_stop();
604 }
605
606 if (rv & WDIOS_ENABLECARD)
607 {
608 return pcwd_start();
609 }
610
611 if (rv & WDIOS_TEMPPANIC)
612 {
613 temp_panic = 1;
614 }
615 }
616 return -EINVAL;
617
618 case WDIOC_KEEPALIVE:
619 pcwd_keepalive();
620 return 0;
621
622 case WDIOC_SETTIMEOUT:
623 if (get_user(new_heartbeat, argp))
624 return -EFAULT;
625
626 if (pcwd_set_heartbeat(new_heartbeat))
627 return -EINVAL;
628
629 pcwd_keepalive();
630 /* Fall */
631
632 case WDIOC_GETTIMEOUT:
633 return put_user(heartbeat, argp);
634 }
635
636 return 0;
637 }
638
639 static ssize_t pcwd_write(struct file *file, const char __user *buf, size_t len,
640 loff_t *ppos)
641 {
642 if (len) {
643 if (!nowayout) {
644 size_t i;
645
646 /* In case it was set long ago */
647 expect_close = 0;
648
649 for (i = 0; i != len; i++) {
650 char c;
651
652 if (get_user(c, buf + i))
653 return -EFAULT;
654 if (c == 'V')
655 expect_close = 42;
656 }
657 }
658 pcwd_keepalive();
659 }
660 return len;
661 }
662
663 static int pcwd_open(struct inode *inode, struct file *file)
664 {
665 if (!atomic_dec_and_test(&open_allowed) ) {
666 if (debug >= VERBOSE)
667 printk(KERN_ERR PFX "Attempt to open already opened device.\n");
668 atomic_inc( &open_allowed );
669 return -EBUSY;
670 }
671
672 if (nowayout)
673 __module_get(THIS_MODULE);
674
675 /* Activate */
676 pcwd_start();
677 pcwd_keepalive();
678 return nonseekable_open(inode, file);
679 }
680
681 static int pcwd_close(struct inode *inode, struct file *file)
682 {
683 if (expect_close == 42) {
684 pcwd_stop();
685 } else {
686 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
687 pcwd_keepalive();
688 }
689 expect_close = 0;
690 atomic_inc( &open_allowed );
691 return 0;
692 }
693
694 /*
695 * /dev/temperature handling
696 */
697
698 static ssize_t pcwd_temp_read(struct file *file, char __user *buf, size_t count,
699 loff_t *ppos)
700 {
701 int temperature;
702
703 if (pcwd_get_temperature(&temperature))
704 return -EFAULT;
705
706 if (copy_to_user(buf, &temperature, 1))
707 return -EFAULT;
708
709 return 1;
710 }
711
712 static int pcwd_temp_open(struct inode *inode, struct file *file)
713 {
714 if (!pcwd_private.supports_temp)
715 return -ENODEV;
716
717 return nonseekable_open(inode, file);
718 }
719
720 static int pcwd_temp_close(struct inode *inode, struct file *file)
721 {
722 return 0;
723 }
724
725 /*
726 * Notify system
727 */
728
729 static int pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
730 {
731 if (code==SYS_DOWN || code==SYS_HALT) {
732 /* Turn the WDT off */
733 pcwd_stop();
734 }
735
736 return NOTIFY_DONE;
737 }
738
739 /*
740 * Kernel Interfaces
741 */
742
743 static struct file_operations pcwd_fops = {
744 .owner = THIS_MODULE,
745 .llseek = no_llseek,
746 .write = pcwd_write,
747 .ioctl = pcwd_ioctl,
748 .open = pcwd_open,
749 .release = pcwd_close,
750 };
751
752 static struct miscdevice pcwd_miscdev = {
753 .minor = WATCHDOG_MINOR,
754 .name = "watchdog",
755 .fops = &pcwd_fops,
756 };
757
758 static struct file_operations pcwd_temp_fops = {
759 .owner = THIS_MODULE,
760 .llseek = no_llseek,
761 .read = pcwd_temp_read,
762 .open = pcwd_temp_open,
763 .release = pcwd_temp_close,
764 };
765
766 static struct miscdevice temp_miscdev = {
767 .minor = TEMP_MINOR,
768 .name = "temperature",
769 .fops = &pcwd_temp_fops,
770 };
771
772 static struct notifier_block pcwd_notifier = {
773 .notifier_call = pcwd_notify_sys,
774 };
775
776 /*
777 * Init & exit routines
778 */
779
780 static inline int get_revision(void)
781 {
782 int r = PCWD_REVISION_C;
783
784 spin_lock(&pcwd_private.io_lock);
785 /* REV A cards use only 2 io ports; test
786 * presumes a floating bus reads as 0xff. */
787 if ((inb(pcwd_private.io_addr + 2) == 0xFF) ||
788 (inb(pcwd_private.io_addr + 3) == 0xFF))
789 r=PCWD_REVISION_A;
790 spin_unlock(&pcwd_private.io_lock);
791
792 return r;
793 }
794
795 static int __devinit pcwatchdog_init(int base_addr)
796 {
797 int ret;
798
799 cards_found++;
800 if (cards_found == 1)
801 printk(KERN_INFO PFX "v%s Ken Hollis (kenji@bitgate.com)\n", WD_VER);
802
803 if (cards_found > 1) {
804 printk(KERN_ERR PFX "This driver only supports 1 device\n");
805 return -ENODEV;
806 }
807
808 if (base_addr == 0x0000) {
809 printk(KERN_ERR PFX "No I/O-Address for card detected\n");
810 return -ENODEV;
811 }
812 pcwd_private.io_addr = base_addr;
813
814 /* Check card's revision */
815 pcwd_private.revision = get_revision();
816
817 if (!request_region(pcwd_private.io_addr, (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4, "PCWD")) {
818 printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
819 pcwd_private.io_addr);
820 pcwd_private.io_addr = 0x0000;
821 return -EIO;
822 }
823
824 /* Initial variables */
825 pcwd_private.supports_temp = 0;
826 temp_panic = 0;
827 pcwd_private.boot_status = 0x0000;
828
829 /* get the boot_status */
830 pcwd_get_status(&pcwd_private.boot_status);
831
832 /* clear the "card caused reboot" flag */
833 pcwd_clear_status();
834
835 init_timer(&pcwd_private.timer);
836 pcwd_private.timer.function = pcwd_timer_ping;
837 pcwd_private.timer.data = 0;
838
839 /* Disable the board */
840 pcwd_stop();
841
842 /* Check whether or not the card supports the temperature device */
843 pcwd_check_temperature_support();
844
845 /* Show info about the card itself */
846 pcwd_show_card_info();
847
848 /* Check that the heartbeat value is within it's range ; if not reset to the default */
849 if (pcwd_set_heartbeat(heartbeat)) {
850 pcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
851 printk(KERN_INFO PFX "heartbeat value must be 2<=heartbeat<=7200, using %d\n",
852 WATCHDOG_HEARTBEAT);
853 }
854
855 ret = register_reboot_notifier(&pcwd_notifier);
856 if (ret) {
857 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
858 ret);
859 release_region(pcwd_private.io_addr, (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
860 pcwd_private.io_addr = 0x0000;
861 return ret;
862 }
863
864 if (pcwd_private.supports_temp) {
865 ret = misc_register(&temp_miscdev);
866 if (ret) {
867 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
868 TEMP_MINOR, ret);
869 unregister_reboot_notifier(&pcwd_notifier);
870 release_region(pcwd_private.io_addr, (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
871 pcwd_private.io_addr = 0x0000;
872 return ret;
873 }
874 }
875
876 ret = misc_register(&pcwd_miscdev);
877 if (ret) {
878 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
879 WATCHDOG_MINOR, ret);
880 if (pcwd_private.supports_temp)
881 misc_deregister(&temp_miscdev);
882 unregister_reboot_notifier(&pcwd_notifier);
883 release_region(pcwd_private.io_addr, (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
884 pcwd_private.io_addr = 0x0000;
885 return ret;
886 }
887
888 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
889 heartbeat, nowayout);
890
891 return 0;
892 }
893
894 static void __devexit pcwatchdog_exit(void)
895 {
896 /* Disable the board */
897 if (!nowayout)
898 pcwd_stop();
899
900 /* Deregister */
901 misc_deregister(&pcwd_miscdev);
902 if (pcwd_private.supports_temp)
903 misc_deregister(&temp_miscdev);
904 unregister_reboot_notifier(&pcwd_notifier);
905 release_region(pcwd_private.io_addr, (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
906 pcwd_private.io_addr = 0x0000;
907 cards_found--;
908 }
909
910 /*
911 * The ISA cards have a heartbeat bit in one of the registers, which
912 * register is card dependent. The heartbeat bit is monitored, and if
913 * found, is considered proof that a Berkshire card has been found.
914 * The initial rate is once per second at board start up, then twice
915 * per second for normal operation.
916 */
917 static int __init pcwd_checkcard(int base_addr)
918 {
919 int port0, last_port0; /* Reg 0, in case it's REV A */
920 int port1, last_port1; /* Register 1 for REV C cards */
921 int i;
922 int retval;
923
924 if (!request_region (base_addr, 4, "PCWD")) {
925 printk (KERN_INFO PFX "Port 0x%04x unavailable\n", base_addr);
926 return 0;
927 }
928
929 retval = 0;
930
931 port0 = inb_p(base_addr); /* For REV A boards */
932 port1 = inb_p(base_addr + 1); /* For REV C boards */
933 if (port0 != 0xff || port1 != 0xff) {
934 /* Not an 'ff' from a floating bus, so must be a card! */
935 for (i = 0; i < 4; ++i) {
936
937 msleep(500);
938
939 last_port0 = port0;
940 last_port1 = port1;
941
942 port0 = inb_p(base_addr);
943 port1 = inb_p(base_addr + 1);
944
945 /* Has either hearbeat bit changed? */
946 if ((port0 ^ last_port0) & WD_HRTBT ||
947 (port1 ^ last_port1) & WD_REVC_HRBT) {
948 retval = 1;
949 break;
950 }
951 }
952 }
953 release_region (base_addr, 4);
954
955 return retval;
956 }
957
958 /*
959 * These are the auto-probe addresses available.
960 *
961 * Revision A only uses ports 0x270 and 0x370. Revision C introduced 0x350.
962 * Revision A has an address range of 2 addresses, while Revision C has 4.
963 */
964 static int pcwd_ioports[] = { 0x270, 0x350, 0x370, 0x000 };
965
966 static int __init pcwd_init_module(void)
967 {
968 int i, found = 0;
969
970 spin_lock_init(&pcwd_private.io_lock);
971
972 for (i = 0; pcwd_ioports[i] != 0; i++) {
973 if (pcwd_checkcard(pcwd_ioports[i])) {
974 if (!(pcwatchdog_init(pcwd_ioports[i])))
975 found++;
976 }
977 }
978
979 if (!found) {
980 printk (KERN_INFO PFX "No card detected, or port not available\n");
981 return -ENODEV;
982 }
983
984 return 0;
985 }
986
987 static void __exit pcwd_cleanup_module(void)
988 {
989 if (pcwd_private.io_addr)
990 pcwatchdog_exit();
991
992 printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
993 }
994
995 module_init(pcwd_init_module);
996 module_exit(pcwd_cleanup_module);
997
998 MODULE_AUTHOR("Ken Hollis <kenji@bitgate.com>");
999 MODULE_DESCRIPTION("Berkshire ISA-PC Watchdog driver");
1000 MODULE_LICENSE("GPL");
1001 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
1002 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
1003
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