File: /usr/src/linux/drivers/char/wdt_pci.c
1 /*
2 * Industrial Computer Source WDT500/501 driver for Linux 2.1.x
3 *
4 * (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved.
5 * http://www.redhat.com
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
13 * warranty for any of this software. This material is provided
14 * "AS-IS" and at no charge.
15 *
16 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
17 *
18 * Release 0.08.
19 *
20 * Fixes
21 * Dave Gregorich : Modularisation and minor bugs
22 * Alan Cox : Added the watchdog ioctl() stuff
23 * Alan Cox : Fixed the reboot problem (as noted by
24 * Matt Crocker).
25 * Alan Cox : Added wdt= boot option
26 * Alan Cox : Cleaned up copy/user stuff
27 * Tim Hockin : Added insmod parameters, comment cleanup
28 * Parameterized timeout
29 * JP Nollmann : Added support for PCI wdt501p
30 * Alan Cox : Split ISA and PCI cards into two drivers
31 * Jeff Garzik : PCI cleanups
32 * Tigran Aivazian : Restructured wdtpci_init_one() to handle failures
33 */
34
35 #include <linux/config.h>
36 #include <linux/module.h>
37 #include <linux/version.h>
38 #include <linux/types.h>
39 #include <linux/errno.h>
40 #include <linux/kernel.h>
41 #include <linux/sched.h>
42 #include <linux/miscdevice.h>
43 #include <linux/watchdog.h>
44 #define WDT_IS_PCI
45 #include "wd501p.h"
46 #include <linux/slab.h>
47 #include <linux/ioport.h>
48 #include <linux/fcntl.h>
49 #include <asm/io.h>
50 #include <asm/uaccess.h>
51 #include <asm/system.h>
52 #include <linux/notifier.h>
53 #include <linux/reboot.h>
54 #include <linux/init.h>
55 #include <linux/smp_lock.h>
56
57 #include <linux/pci.h>
58
59 #define PFX "wdt_pci: "
60
61 /*
62 * Until Access I/O gets their application for a PCI vendor ID approved,
63 * I don't think that it's appropriate to move these constants into the
64 * regular pci_ids.h file. -- JPN 2000/01/18
65 */
66
67 #ifndef PCI_VENDOR_ID_ACCESSIO
68 #define PCI_VENDOR_ID_ACCESSIO 0x494f
69 #endif
70 #ifndef PCI_DEVICE_ID_WDG_CSM
71 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
72 #endif
73
74 static int wdt_is_open;
75
76 /*
77 * You must set these - there is no sane way to probe for this board.
78 * You can use wdt=x,y to set these now.
79 */
80
81 static int io=0x240;
82 static int irq=11;
83
84 #define WD_TIMO (100*60) /* 1 minute */
85
86 #ifndef MODULE
87
88 /**
89 * wdtpci_setup:
90 * @str: command line string
91 *
92 * Setup options. The board isn't really probe-able so we have to
93 * get the user to tell us the configuration. Sane people build it
94 * modular but the others come here.
95 */
96
97 static int __init wdtpci_setup(char *str)
98 {
99 int ints[4];
100
101 str = get_options (str, ARRAY_SIZE(ints), ints);
102
103 if (ints[0] > 0)
104 {
105 io = ints[1];
106 if(ints[0] > 1)
107 irq = ints[2];
108 }
109
110 return 1;
111 }
112
113 __setup("wdt=", wdtpci_setup);
114
115 #endif /* !MODULE */
116
117 /*
118 * Programming support
119 */
120
121 static void wdtpci_ctr_mode(int ctr, int mode)
122 {
123 ctr<<=6;
124 ctr|=0x30;
125 ctr|=(mode<<1);
126 outb_p(ctr, WDT_CR);
127 }
128
129 static void wdtpci_ctr_load(int ctr, int val)
130 {
131 outb_p(val&0xFF, WDT_COUNT0+ctr);
132 outb_p(val>>8, WDT_COUNT0+ctr);
133 }
134
135 /*
136 * Kernel methods.
137 */
138
139
140 /**
141 * wdtpci_status:
142 *
143 * Extract the status information from a WDT watchdog device. There are
144 * several board variants so we have to know which bits are valid. Some
145 * bits default to one and some to zero in order to be maximally painful.
146 *
147 * we then map the bits onto the status ioctl flags.
148 */
149
150 static int wdtpci_status(void)
151 {
152 /*
153 * Status register to bit flags
154 */
155
156 int flag=0;
157 unsigned char status=inb_p(WDT_SR);
158 status|=FEATUREMAP1;
159 status&=~FEATUREMAP2;
160
161 if(!(status&WDC_SR_TGOOD))
162 flag|=WDIOF_OVERHEAT;
163 if(!(status&WDC_SR_PSUOVER))
164 flag|=WDIOF_POWEROVER;
165 if(!(status&WDC_SR_PSUUNDR))
166 flag|=WDIOF_POWERUNDER;
167 if(!(status&WDC_SR_FANGOOD))
168 flag|=WDIOF_FANFAULT;
169 if(status&WDC_SR_ISOI0)
170 flag|=WDIOF_EXTERN1;
171 if(status&WDC_SR_ISII1)
172 flag|=WDIOF_EXTERN2;
173 return flag;
174 }
175
176 /**
177 * wdtpci_interrupt:
178 * @irq: Interrupt number
179 * @dev_id: Unused as we don't allow multiple devices.
180 * @regs: Unused.
181 *
182 * Handle an interrupt from the board. These are raised when the status
183 * map changes in what the board considers an interesting way. That means
184 * a failure condition occuring.
185 */
186
187 static void wdtpci_interrupt(int irq, void *dev_id, struct pt_regs *regs)
188 {
189 /*
190 * Read the status register see what is up and
191 * then printk it.
192 */
193
194 unsigned char status=inb_p(WDT_SR);
195
196 status|=FEATUREMAP1;
197 status&=~FEATUREMAP2;
198
199 printk(KERN_CRIT "WDT status %d\n", status);
200
201 if(!(status&WDC_SR_TGOOD))
202 printk(KERN_CRIT "Overheat alarm.(%d)\n",inb_p(WDT_RT));
203 if(!(status&WDC_SR_PSUOVER))
204 printk(KERN_CRIT "PSU over voltage.\n");
205 if(!(status&WDC_SR_PSUUNDR))
206 printk(KERN_CRIT "PSU under voltage.\n");
207 if(!(status&WDC_SR_FANGOOD))
208 printk(KERN_CRIT "Possible fan fault.\n");
209 if(!(status&WDC_SR_WCCR))
210 #ifdef SOFTWARE_REBOOT
211 #ifdef ONLY_TESTING
212 printk(KERN_CRIT "Would Reboot.\n");
213 #else
214 printk(KERN_CRIT "Initiating system reboot.\n");
215 machine_restart(NULL);
216 #endif
217 #else
218 printk(KERN_CRIT "Reset in 5ms.\n");
219 #endif
220 }
221
222
223 /**
224 * wdtpci_ping:
225 *
226 * Reload counter one with the watchdog timeout. We don't bother reloading
227 * the cascade counter.
228 */
229
230 static void wdtpci_ping(void)
231 {
232 /* Write a watchdog value */
233 inb_p(WDT_DC);
234 wdtpci_ctr_mode(1,2);
235 wdtpci_ctr_load(1,WD_TIMO); /* Timeout */
236 outb_p(0, WDT_DC);
237 }
238
239 /**
240 * wdtpci_write:
241 * @file: file handle to the watchdog
242 * @buf: buffer to write (unused as data does not matter here
243 * @count: count of bytes
244 * @ppos: pointer to the position to write. No seeks allowed
245 *
246 * A write to a watchdog device is defined as a keepalive signal. Any
247 * write of data will do, as we we don't define content meaning.
248 */
249
250 static ssize_t wdtpci_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
251 {
252 /* Can't seek (pwrite) on this device */
253 if (ppos != &file->f_pos)
254 return -ESPIPE;
255
256 if(count)
257 {
258 wdtpci_ping();
259 return 1;
260 }
261 return 0;
262 }
263
264 /**
265 * wdtpci_read:
266 * @file: file handle to the watchdog board
267 * @buf: buffer to write 1 byte into
268 * @count: length of buffer
269 * @ptr: offset (no seek allowed)
270 *
271 * Read reports the temperature in degrees Fahrenheit. The API is in
272 * fahrenheit. It was designed by an imperial measurement luddite.
273 */
274
275 static ssize_t wdtpci_read(struct file *file, char *buf, size_t count, loff_t *ptr)
276 {
277 unsigned short c=inb_p(WDT_RT);
278 unsigned char cp;
279
280 /* Can't seek (pread) on this device */
281 if (ptr != &file->f_pos)
282 return -ESPIPE;
283
284 switch(MINOR(file->f_dentry->d_inode->i_rdev))
285 {
286 case TEMP_MINOR:
287 c*=11;
288 c/=15;
289 cp=c+7;
290 if(copy_to_user(buf,&cp,1))
291 return -EFAULT;
292 return 1;
293 default:
294 return -EINVAL;
295 }
296 }
297
298 /**
299 * wdtpci_ioctl:
300 * @inode: inode of the device
301 * @file: file handle to the device
302 * @cmd: watchdog command
303 * @arg: argument pointer
304 *
305 * The watchdog API defines a common set of functions for all watchdogs
306 * according to their available features. We only actually usefully support
307 * querying capabilities and current status.
308 */
309
310 static int wdtpci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
311 unsigned long arg)
312 {
313 static struct watchdog_info ident=
314 {
315 WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER
316 |WDIOF_EXTERN1|WDIOF_EXTERN2|WDIOF_FANFAULT,
317 1,
318 "WDT500/501PCI"
319 };
320
321 ident.options&=WDT_OPTION_MASK; /* Mask down to the card we have */
322 switch(cmd)
323 {
324 default:
325 return -ENOTTY;
326 case WDIOC_GETSUPPORT:
327 return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0;
328
329 case WDIOC_GETSTATUS:
330 return put_user(wdtpci_status(),(int *)arg);
331 case WDIOC_GETBOOTSTATUS:
332 return put_user(0, (int *)arg);
333 case WDIOC_KEEPALIVE:
334 wdtpci_ping();
335 return 0;
336 }
337 }
338
339 /**
340 * wdtpci_open:
341 * @inode: inode of device
342 * @file: file handle to device
343 *
344 * One of our two misc devices has been opened. The watchdog device is
345 * single open and on opening we load the counters. Counter zero is a
346 * 100Hz cascade, into counter 1 which downcounts to reboot. When the
347 * counter triggers counter 2 downcounts the length of the reset pulse
348 * which set set to be as long as possible.
349 */
350
351 static int wdtpci_open(struct inode *inode, struct file *file)
352 {
353 switch(MINOR(inode->i_rdev))
354 {
355 case WATCHDOG_MINOR:
356 if(wdt_is_open)
357 return -EBUSY;
358 #ifdef CONFIG_WATCHDOG_NOWAYOUT
359 MOD_INC_USE_COUNT;
360 #endif
361 /*
362 * Activate
363 */
364
365 wdt_is_open=1;
366
367 inb_p(WDT_DC); /* Disable */
368
369 /*
370 * "pet" the watchdog, as Access says.
371 * This resets the clock outputs.
372 */
373
374 wdtpci_ctr_mode(2,0);
375 outb_p(0, WDT_DC);
376
377 inb_p(WDT_DC);
378
379 outb_p(0, WDT_CLOCK); /* 2.0833MHz clock */
380 inb_p(WDT_BUZZER); /* disable */
381 inb_p(WDT_OPTONOTRST); /* disable */
382 inb_p(WDT_OPTORST); /* disable */
383 inb_p(WDT_PROGOUT); /* disable */
384 wdtpci_ctr_mode(0,3);
385 wdtpci_ctr_mode(1,2);
386 wdtpci_ctr_mode(2,1);
387 wdtpci_ctr_load(0,20833); /* count at 100Hz */
388 wdtpci_ctr_load(1,WD_TIMO);/* Timeout 60 seconds */
389 /* DO NOT LOAD CTR2 on PCI card! -- JPN */
390 outb_p(0, WDT_DC); /* Enable */
391 return 0;
392 case TEMP_MINOR:
393 return 0;
394 default:
395 return -ENODEV;
396 }
397 }
398
399 /**
400 * wdtpci_close:
401 * @inode: inode to board
402 * @file: file handle to board
403 *
404 * The watchdog has a configurable API. There is a religious dispute
405 * between people who want their watchdog to be able to shut down and
406 * those who want to be sure if the watchdog manager dies the machine
407 * reboots. In the former case we disable the counters, in the latter
408 * case you have to open it again very soon.
409 */
410
411 static int wdtpci_release(struct inode *inode, struct file *file)
412 {
413 if(MINOR(inode->i_rdev)==WATCHDOG_MINOR)
414 {
415 lock_kernel();
416 #ifndef CONFIG_WATCHDOG_NOWAYOUT
417 inb_p(WDT_DC); /* Disable counters */
418 wdtpci_ctr_load(2,0); /* 0 length reset pulses now */
419 #endif
420 wdt_is_open=0;
421 unlock_kernel();
422 }
423 return 0;
424 }
425
426 /**
427 * notify_sys:
428 * @this: our notifier block
429 * @code: the event being reported
430 * @unused: unused
431 *
432 * Our notifier is called on system shutdowns. We want to turn the card
433 * off at reboot otherwise the machine will reboot again during memory
434 * test or worse yet during the following fsck. This would suck, in fact
435 * trust me - if it happens it does suck.
436 */
437
438 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
439 void *unused)
440 {
441 if(code==SYS_DOWN || code==SYS_HALT)
442 {
443 /* Turn the card off */
444 inb_p(WDT_DC);
445 wdtpci_ctr_load(2,0);
446 }
447 return NOTIFY_DONE;
448 }
449
450 /*
451 * Kernel Interfaces
452 */
453
454
455 static struct file_operations wdtpci_fops = {
456 owner: THIS_MODULE,
457 llseek: no_llseek,
458 read: wdtpci_read,
459 write: wdtpci_write,
460 ioctl: wdtpci_ioctl,
461 open: wdtpci_open,
462 release: wdtpci_release,
463 };
464
465 static struct miscdevice wdtpci_miscdev=
466 {
467 WATCHDOG_MINOR,
468 "watchdog",
469 &wdtpci_fops
470 };
471
472 #ifdef CONFIG_WDT_501
473 static struct miscdevice temp_miscdev=
474 {
475 TEMP_MINOR,
476 "temperature",
477 &wdtpci_fops
478 };
479 #endif
480
481 /*
482 * The WDT card needs to learn about soft shutdowns in order to
483 * turn the timebomb registers off.
484 */
485
486 static struct notifier_block wdtpci_notifier=
487 {
488 wdtpci_notify_sys,
489 NULL,
490 0
491 };
492
493
494 static int __init wdtpci_init_one (struct pci_dev *dev,
495 const struct pci_device_id *ent)
496 {
497 static int dev_count = 0;
498 int ret = -EIO;
499
500 dev_count++;
501 if (dev_count > 1) {
502 printk (KERN_ERR PFX
503 "this driver only supports 1 device\n");
504 return -ENODEV;
505 }
506
507 irq = dev->irq;
508 io = pci_resource_start (dev, 2);
509 printk ("WDT501-P(PCI-WDG-CSM) driver 0.07 at %X "
510 "(Interrupt %d)\n", io, irq);
511
512 if (pci_enable_device (dev))
513 goto out;
514
515 if (request_region (io, 16, "wdt-pci") == NULL) {
516 printk (KERN_ERR PFX "I/O %d is not free.\n", io);
517 goto out;
518 }
519
520 if (request_irq (irq, wdtpci_interrupt, SA_INTERRUPT | SA_SHIRQ,
521 "wdt-pci", &wdtpci_miscdev)) {
522 printk (KERN_ERR PFX "IRQ %d is not free.\n", irq);
523 goto out_reg;
524 }
525
526 ret = misc_register (&wdtpci_miscdev);
527 if (ret) {
528 printk (KERN_ERR PFX "can't misc_register on minor=%d\n", WATCHDOG_MINOR);
529 goto out_irq;
530 }
531
532 ret = register_reboot_notifier (&wdtpci_notifier);
533 if (ret) {
534 printk (KERN_ERR PFX "can't misc_register on minor=%d\n", WATCHDOG_MINOR);
535 goto out_misc;
536 }
537 #ifdef CONFIG_WDT_501
538 ret = misc_register (&temp_miscdev);
539 if (ret) {
540 printk (KERN_ERR PFX "can't misc_register (temp) on minor=%d\n", TEMP_MINOR);
541 goto out_rbt;
542 }
543 #endif
544
545 ret = 0;
546 out:
547 return ret;
548
549 #ifdef CONFIG_WDT_501
550 out_rbt:
551 unregister_reboot_notifier(&wdtpci_notifier);
552 #endif
553 out_misc:
554 misc_deregister(&wdtpci_miscdev);
555 out_irq:
556 free_irq(irq, &wdtpci_miscdev);
557 out_reg:
558 release_region (io, 16);
559 goto out;
560 }
561
562
563 static void __exit wdtpci_remove_one (struct pci_dev *pdev)
564 {
565 /* here we assume only one device will ever have
566 * been picked up and registered by probe function */
567 unregister_reboot_notifier(&wdtpci_notifier);
568 #ifdef CONFIG_WDT_501_PCI
569 misc_deregister(&temp_miscdev);
570 #endif
571 misc_deregister(&wdtpci_miscdev);
572 free_irq(irq, &wdtpci_miscdev);
573 release_region(io, 16);
574 }
575
576
577 static struct pci_device_id wdtpci_pci_tbl[] __initdata = {
578 { PCI_VENDOR_ID_ACCESSIO, PCI_DEVICE_ID_WDG_CSM, PCI_ANY_ID, PCI_ANY_ID, },
579 { 0, }, /* terminate list */
580 };
581 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
582
583
584 static struct pci_driver wdtpci_driver = {
585 name: "wdt-pci",
586 id_table: wdtpci_pci_tbl,
587 probe: wdtpci_init_one,
588 remove: wdtpci_remove_one,
589 };
590
591
592 /**
593 * wdtpci_cleanup:
594 *
595 * Unload the watchdog. You cannot do this with any file handles open.
596 * If your watchdog is set to continue ticking on close and you unload
597 * it, well it keeps ticking. We won't get the interrupt but the board
598 * will not touch PC memory so all is fine. You just have to load a new
599 * module in 60 seconds or reboot.
600 */
601
602 static void __exit wdtpci_cleanup(void)
603 {
604 pci_unregister_driver (&wdtpci_driver);
605 }
606
607
608 /**
609 * wdtpci_init:
610 *
611 * Set up the WDT watchdog board. All we have to do is grab the
612 * resources we require and bitch if anyone beat us to them.
613 * The open() function will actually kick the board off.
614 */
615
616 static int __init wdtpci_init(void)
617 {
618 int rc = pci_register_driver (&wdtpci_driver);
619
620 if (rc < 1)
621 return -ENODEV;
622
623 return 0;
624 }
625
626
627 module_init(wdtpci_init);
628 module_exit(wdtpci_cleanup);
629
630 MODULE_AUTHOR("JP Nollmann, Alan Cox");
631 MODULE_DESCRIPTION("Driver for the ICS PCI watchdog cards");
632 MODULE_LICENSE("GPL");
633
634 EXPORT_NO_SYMBOLS;
635