xref: /openbmc/linux/drivers/watchdog/iTCO_wdt.c (revision 206a81c1)
1 /*
2  *	intel TCO Watchdog Driver
3  *
4  *	(c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License
8  *	as published by the Free Software Foundation; either version
9  *	2 of the License, or (at your option) any later version.
10  *
11  *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
12  *	provide warranty for any of this software. This material is
13  *	provided "AS-IS" and at no charge.
14  *
15  *	The TCO watchdog is implemented in the following I/O controller hubs:
16  *	(See the intel documentation on http://developer.intel.com.)
17  *	document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
18  *	document number 290687-002, 298242-027: 82801BA (ICH2)
19  *	document number 290733-003, 290739-013: 82801CA (ICH3-S)
20  *	document number 290716-001, 290718-007: 82801CAM (ICH3-M)
21  *	document number 290744-001, 290745-025: 82801DB (ICH4)
22  *	document number 252337-001, 252663-008: 82801DBM (ICH4-M)
23  *	document number 273599-001, 273645-002: 82801E (C-ICH)
24  *	document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
25  *	document number 300641-004, 300884-013: 6300ESB
26  *	document number 301473-002, 301474-026: 82801F (ICH6)
27  *	document number 313082-001, 313075-006: 631xESB, 632xESB
28  *	document number 307013-003, 307014-024: 82801G (ICH7)
29  *	document number 322896-001, 322897-001: NM10
30  *	document number 313056-003, 313057-017: 82801H (ICH8)
31  *	document number 316972-004, 316973-012: 82801I (ICH9)
32  *	document number 319973-002, 319974-002: 82801J (ICH10)
33  *	document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
34  *	document number 320066-003, 320257-008: EP80597 (IICH)
35  *	document number 324645-001, 324646-001: Cougar Point (CPT)
36  *	document number TBD                   : Patsburg (PBG)
37  *	document number TBD                   : DH89xxCC
38  *	document number TBD                   : Panther Point
39  *	document number TBD                   : Lynx Point
40  *	document number TBD                   : Lynx Point-LP
41  */
42 
43 /*
44  *	Includes, defines, variables, module parameters, ...
45  */
46 
47 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
48 
49 /* Module and version information */
50 #define DRV_NAME	"iTCO_wdt"
51 #define DRV_VERSION	"1.11"
52 
53 /* Includes */
54 #include <linux/module.h>		/* For module specific items */
55 #include <linux/moduleparam.h>		/* For new moduleparam's */
56 #include <linux/types.h>		/* For standard types (like size_t) */
57 #include <linux/errno.h>		/* For the -ENODEV/... values */
58 #include <linux/kernel.h>		/* For printk/panic/... */
59 #include <linux/watchdog.h>		/* For the watchdog specific items */
60 #include <linux/init.h>			/* For __init/__exit/... */
61 #include <linux/fs.h>			/* For file operations */
62 #include <linux/platform_device.h>	/* For platform_driver framework */
63 #include <linux/pci.h>			/* For pci functions */
64 #include <linux/ioport.h>		/* For io-port access */
65 #include <linux/spinlock.h>		/* For spin_lock/spin_unlock/... */
66 #include <linux/uaccess.h>		/* For copy_to_user/put_user/... */
67 #include <linux/io.h>			/* For inb/outb/... */
68 #include <linux/mfd/core.h>
69 #include <linux/mfd/lpc_ich.h>
70 
71 #include "iTCO_vendor.h"
72 
73 /* Address definitions for the TCO */
74 /* TCO base address */
75 #define TCOBASE		(iTCO_wdt_private.tco_res->start)
76 /* SMI Control and Enable Register */
77 #define SMI_EN		(iTCO_wdt_private.smi_res->start)
78 
79 #define TCO_RLD		(TCOBASE + 0x00) /* TCO Timer Reload and Curr. Value */
80 #define TCOv1_TMR	(TCOBASE + 0x01) /* TCOv1 Timer Initial Value	*/
81 #define TCO_DAT_IN	(TCOBASE + 0x02) /* TCO Data In Register	*/
82 #define TCO_DAT_OUT	(TCOBASE + 0x03) /* TCO Data Out Register	*/
83 #define TCO1_STS	(TCOBASE + 0x04) /* TCO1 Status Register	*/
84 #define TCO2_STS	(TCOBASE + 0x06) /* TCO2 Status Register	*/
85 #define TCO1_CNT	(TCOBASE + 0x08) /* TCO1 Control Register	*/
86 #define TCO2_CNT	(TCOBASE + 0x0a) /* TCO2 Control Register	*/
87 #define TCOv2_TMR	(TCOBASE + 0x12) /* TCOv2 Timer Initial Value	*/
88 
89 /* internal variables */
90 static struct {		/* this is private data for the iTCO_wdt device */
91 	/* TCO version/generation */
92 	unsigned int iTCO_version;
93 	struct resource *tco_res;
94 	struct resource *smi_res;
95 	/*
96 	 * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2),
97 	 * or memory-mapped PMC register bit 4 (TCO version 3).
98 	 */
99 	struct resource *gcs_pmc_res;
100 	unsigned long __iomem *gcs_pmc;
101 	/* the lock for io operations */
102 	spinlock_t io_lock;
103 	struct platform_device *dev;
104 	/* the PCI-device */
105 	struct pci_dev *pdev;
106 } iTCO_wdt_private;
107 
108 /* module parameters */
109 #define WATCHDOG_TIMEOUT 30	/* 30 sec default heartbeat */
110 static int heartbeat = WATCHDOG_TIMEOUT;  /* in seconds */
111 module_param(heartbeat, int, 0);
112 MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
113 	"5..76 (TCO v1) or 3..614 (TCO v2), default="
114 				__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
115 
116 static bool nowayout = WATCHDOG_NOWAYOUT;
117 module_param(nowayout, bool, 0);
118 MODULE_PARM_DESC(nowayout,
119 	"Watchdog cannot be stopped once started (default="
120 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
121 
122 static int turn_SMI_watchdog_clear_off = 1;
123 module_param(turn_SMI_watchdog_clear_off, int, 0);
124 MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
125 	"Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
126 
127 /*
128  * Some TCO specific functions
129  */
130 
131 /*
132  * The iTCO v1 and v2's internal timer is stored as ticks which decrement
133  * every 0.6 seconds.  v3's internal timer is stored as seconds (some
134  * datasheets incorrectly state 0.6 seconds).
135  */
136 static inline unsigned int seconds_to_ticks(int secs)
137 {
138 	return iTCO_wdt_private.iTCO_version == 3 ? secs : (secs * 10) / 6;
139 }
140 
141 static inline unsigned int ticks_to_seconds(int ticks)
142 {
143 	return iTCO_wdt_private.iTCO_version == 3 ? ticks : (ticks * 6) / 10;
144 }
145 
146 static void iTCO_wdt_set_NO_REBOOT_bit(void)
147 {
148 	u32 val32;
149 
150 	/* Set the NO_REBOOT bit: this disables reboots */
151 	if (iTCO_wdt_private.iTCO_version == 3) {
152 		val32 = readl(iTCO_wdt_private.gcs_pmc);
153 		val32 |= 0x00000010;
154 		writel(val32, iTCO_wdt_private.gcs_pmc);
155 	} else if (iTCO_wdt_private.iTCO_version == 2) {
156 		val32 = readl(iTCO_wdt_private.gcs_pmc);
157 		val32 |= 0x00000020;
158 		writel(val32, iTCO_wdt_private.gcs_pmc);
159 	} else if (iTCO_wdt_private.iTCO_version == 1) {
160 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
161 		val32 |= 0x00000002;
162 		pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
163 	}
164 }
165 
166 static int iTCO_wdt_unset_NO_REBOOT_bit(void)
167 {
168 	int ret = 0;
169 	u32 val32;
170 
171 	/* Unset the NO_REBOOT bit: this enables reboots */
172 	if (iTCO_wdt_private.iTCO_version == 3) {
173 		val32 = readl(iTCO_wdt_private.gcs_pmc);
174 		val32 &= 0xffffffef;
175 		writel(val32, iTCO_wdt_private.gcs_pmc);
176 
177 		val32 = readl(iTCO_wdt_private.gcs_pmc);
178 		if (val32 & 0x00000010)
179 			ret = -EIO;
180 	} else if (iTCO_wdt_private.iTCO_version == 2) {
181 		val32 = readl(iTCO_wdt_private.gcs_pmc);
182 		val32 &= 0xffffffdf;
183 		writel(val32, iTCO_wdt_private.gcs_pmc);
184 
185 		val32 = readl(iTCO_wdt_private.gcs_pmc);
186 		if (val32 & 0x00000020)
187 			ret = -EIO;
188 	} else if (iTCO_wdt_private.iTCO_version == 1) {
189 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
190 		val32 &= 0xfffffffd;
191 		pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
192 
193 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
194 		if (val32 & 0x00000002)
195 			ret = -EIO;
196 	}
197 
198 	return ret; /* returns: 0 = OK, -EIO = Error */
199 }
200 
201 static int iTCO_wdt_start(struct watchdog_device *wd_dev)
202 {
203 	unsigned int val;
204 
205 	spin_lock(&iTCO_wdt_private.io_lock);
206 
207 	iTCO_vendor_pre_start(iTCO_wdt_private.smi_res, wd_dev->timeout);
208 
209 	/* disable chipset's NO_REBOOT bit */
210 	if (iTCO_wdt_unset_NO_REBOOT_bit()) {
211 		spin_unlock(&iTCO_wdt_private.io_lock);
212 		pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
213 		return -EIO;
214 	}
215 
216 	/* Force the timer to its reload value by writing to the TCO_RLD
217 	   register */
218 	if (iTCO_wdt_private.iTCO_version >= 2)
219 		outw(0x01, TCO_RLD);
220 	else if (iTCO_wdt_private.iTCO_version == 1)
221 		outb(0x01, TCO_RLD);
222 
223 	/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
224 	val = inw(TCO1_CNT);
225 	val &= 0xf7ff;
226 	outw(val, TCO1_CNT);
227 	val = inw(TCO1_CNT);
228 	spin_unlock(&iTCO_wdt_private.io_lock);
229 
230 	if (val & 0x0800)
231 		return -1;
232 	return 0;
233 }
234 
235 static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
236 {
237 	unsigned int val;
238 
239 	spin_lock(&iTCO_wdt_private.io_lock);
240 
241 	iTCO_vendor_pre_stop(iTCO_wdt_private.smi_res);
242 
243 	/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
244 	val = inw(TCO1_CNT);
245 	val |= 0x0800;
246 	outw(val, TCO1_CNT);
247 	val = inw(TCO1_CNT);
248 
249 	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
250 	iTCO_wdt_set_NO_REBOOT_bit();
251 
252 	spin_unlock(&iTCO_wdt_private.io_lock);
253 
254 	if ((val & 0x0800) == 0)
255 		return -1;
256 	return 0;
257 }
258 
259 static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
260 {
261 	spin_lock(&iTCO_wdt_private.io_lock);
262 
263 	iTCO_vendor_pre_keepalive(iTCO_wdt_private.smi_res, wd_dev->timeout);
264 
265 	/* Reload the timer by writing to the TCO Timer Counter register */
266 	if (iTCO_wdt_private.iTCO_version >= 2) {
267 		outw(0x01, TCO_RLD);
268 	} else if (iTCO_wdt_private.iTCO_version == 1) {
269 		/* Reset the timeout status bit so that the timer
270 		 * needs to count down twice again before rebooting */
271 		outw(0x0008, TCO1_STS);	/* write 1 to clear bit */
272 
273 		outb(0x01, TCO_RLD);
274 	}
275 
276 	spin_unlock(&iTCO_wdt_private.io_lock);
277 	return 0;
278 }
279 
280 static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
281 {
282 	unsigned int val16;
283 	unsigned char val8;
284 	unsigned int tmrval;
285 
286 	tmrval = seconds_to_ticks(t);
287 
288 	/* For TCO v1 the timer counts down twice before rebooting */
289 	if (iTCO_wdt_private.iTCO_version == 1)
290 		tmrval /= 2;
291 
292 	/* from the specs: */
293 	/* "Values of 0h-3h are ignored and should not be attempted" */
294 	if (tmrval < 0x04)
295 		return -EINVAL;
296 	if (((iTCO_wdt_private.iTCO_version >= 2) && (tmrval > 0x3ff)) ||
297 	    ((iTCO_wdt_private.iTCO_version == 1) && (tmrval > 0x03f)))
298 		return -EINVAL;
299 
300 	iTCO_vendor_pre_set_heartbeat(tmrval);
301 
302 	/* Write new heartbeat to watchdog */
303 	if (iTCO_wdt_private.iTCO_version >= 2) {
304 		spin_lock(&iTCO_wdt_private.io_lock);
305 		val16 = inw(TCOv2_TMR);
306 		val16 &= 0xfc00;
307 		val16 |= tmrval;
308 		outw(val16, TCOv2_TMR);
309 		val16 = inw(TCOv2_TMR);
310 		spin_unlock(&iTCO_wdt_private.io_lock);
311 
312 		if ((val16 & 0x3ff) != tmrval)
313 			return -EINVAL;
314 	} else if (iTCO_wdt_private.iTCO_version == 1) {
315 		spin_lock(&iTCO_wdt_private.io_lock);
316 		val8 = inb(TCOv1_TMR);
317 		val8 &= 0xc0;
318 		val8 |= (tmrval & 0xff);
319 		outb(val8, TCOv1_TMR);
320 		val8 = inb(TCOv1_TMR);
321 		spin_unlock(&iTCO_wdt_private.io_lock);
322 
323 		if ((val8 & 0x3f) != tmrval)
324 			return -EINVAL;
325 	}
326 
327 	wd_dev->timeout = t;
328 	return 0;
329 }
330 
331 static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
332 {
333 	unsigned int val16;
334 	unsigned char val8;
335 	unsigned int time_left = 0;
336 
337 	/* read the TCO Timer */
338 	if (iTCO_wdt_private.iTCO_version >= 2) {
339 		spin_lock(&iTCO_wdt_private.io_lock);
340 		val16 = inw(TCO_RLD);
341 		val16 &= 0x3ff;
342 		spin_unlock(&iTCO_wdt_private.io_lock);
343 
344 		time_left = ticks_to_seconds(val16);
345 	} else if (iTCO_wdt_private.iTCO_version == 1) {
346 		spin_lock(&iTCO_wdt_private.io_lock);
347 		val8 = inb(TCO_RLD);
348 		val8 &= 0x3f;
349 		if (!(inw(TCO1_STS) & 0x0008))
350 			val8 += (inb(TCOv1_TMR) & 0x3f);
351 		spin_unlock(&iTCO_wdt_private.io_lock);
352 
353 		time_left = ticks_to_seconds(val8);
354 	}
355 	return time_left;
356 }
357 
358 /*
359  *	Kernel Interfaces
360  */
361 
362 static const struct watchdog_info ident = {
363 	.options =		WDIOF_SETTIMEOUT |
364 				WDIOF_KEEPALIVEPING |
365 				WDIOF_MAGICCLOSE,
366 	.firmware_version =	0,
367 	.identity =		DRV_NAME,
368 };
369 
370 static const struct watchdog_ops iTCO_wdt_ops = {
371 	.owner =		THIS_MODULE,
372 	.start =		iTCO_wdt_start,
373 	.stop =			iTCO_wdt_stop,
374 	.ping =			iTCO_wdt_ping,
375 	.set_timeout =		iTCO_wdt_set_timeout,
376 	.get_timeleft =		iTCO_wdt_get_timeleft,
377 };
378 
379 static struct watchdog_device iTCO_wdt_watchdog_dev = {
380 	.info =		&ident,
381 	.ops =		&iTCO_wdt_ops,
382 };
383 
384 /*
385  *	Init & exit routines
386  */
387 
388 static void iTCO_wdt_cleanup(void)
389 {
390 	/* Stop the timer before we leave */
391 	if (!nowayout)
392 		iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
393 
394 	/* Deregister */
395 	watchdog_unregister_device(&iTCO_wdt_watchdog_dev);
396 
397 	/* release resources */
398 	release_region(iTCO_wdt_private.tco_res->start,
399 			resource_size(iTCO_wdt_private.tco_res));
400 	release_region(iTCO_wdt_private.smi_res->start,
401 			resource_size(iTCO_wdt_private.smi_res));
402 	if (iTCO_wdt_private.iTCO_version >= 2) {
403 		iounmap(iTCO_wdt_private.gcs_pmc);
404 		release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
405 				resource_size(iTCO_wdt_private.gcs_pmc_res));
406 	}
407 
408 	iTCO_wdt_private.tco_res = NULL;
409 	iTCO_wdt_private.smi_res = NULL;
410 	iTCO_wdt_private.gcs_pmc_res = NULL;
411 	iTCO_wdt_private.gcs_pmc = NULL;
412 }
413 
414 static int iTCO_wdt_probe(struct platform_device *dev)
415 {
416 	int ret = -ENODEV;
417 	unsigned long val32;
418 	struct lpc_ich_info *ich_info = dev_get_platdata(&dev->dev);
419 
420 	if (!ich_info)
421 		goto out;
422 
423 	spin_lock_init(&iTCO_wdt_private.io_lock);
424 
425 	iTCO_wdt_private.tco_res =
426 		platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_TCO);
427 	if (!iTCO_wdt_private.tco_res)
428 		goto out;
429 
430 	iTCO_wdt_private.smi_res =
431 		platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_SMI);
432 	if (!iTCO_wdt_private.smi_res)
433 		goto out;
434 
435 	iTCO_wdt_private.iTCO_version = ich_info->iTCO_version;
436 	iTCO_wdt_private.dev = dev;
437 	iTCO_wdt_private.pdev = to_pci_dev(dev->dev.parent);
438 
439 	/*
440 	 * Get the Memory-Mapped GCS or PMC register, we need it for the
441 	 * NO_REBOOT flag (TCO v2 and v3).
442 	 */
443 	if (iTCO_wdt_private.iTCO_version >= 2) {
444 		iTCO_wdt_private.gcs_pmc_res = platform_get_resource(dev,
445 							IORESOURCE_MEM,
446 							ICH_RES_MEM_GCS_PMC);
447 
448 		if (!iTCO_wdt_private.gcs_pmc_res)
449 			goto out;
450 
451 		if (!request_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
452 			resource_size(iTCO_wdt_private.gcs_pmc_res), dev->name)) {
453 			ret = -EBUSY;
454 			goto out;
455 		}
456 		iTCO_wdt_private.gcs_pmc = ioremap(iTCO_wdt_private.gcs_pmc_res->start,
457 			resource_size(iTCO_wdt_private.gcs_pmc_res));
458 		if (!iTCO_wdt_private.gcs_pmc) {
459 			ret = -EIO;
460 			goto unreg_gcs_pmc;
461 		}
462 	}
463 
464 	/* Check chipset's NO_REBOOT bit */
465 	if (iTCO_wdt_unset_NO_REBOOT_bit() && iTCO_vendor_check_noreboot_on()) {
466 		pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
467 		ret = -ENODEV;	/* Cannot reset NO_REBOOT bit */
468 		goto unmap_gcs_pmc;
469 	}
470 
471 	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
472 	iTCO_wdt_set_NO_REBOOT_bit();
473 
474 	/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
475 	if (!request_region(iTCO_wdt_private.smi_res->start,
476 			resource_size(iTCO_wdt_private.smi_res), dev->name)) {
477 		pr_err("I/O address 0x%04llx already in use, device disabled\n",
478 		       (u64)SMI_EN);
479 		ret = -EBUSY;
480 		goto unmap_gcs_pmc;
481 	}
482 	if (turn_SMI_watchdog_clear_off >= iTCO_wdt_private.iTCO_version) {
483 		/*
484 		 * Bit 13: TCO_EN -> 0
485 		 * Disables TCO logic generating an SMI#
486 		 */
487 		val32 = inl(SMI_EN);
488 		val32 &= 0xffffdfff;	/* Turn off SMI clearing watchdog */
489 		outl(val32, SMI_EN);
490 	}
491 
492 	if (!request_region(iTCO_wdt_private.tco_res->start,
493 			resource_size(iTCO_wdt_private.tco_res), dev->name)) {
494 		pr_err("I/O address 0x%04llx already in use, device disabled\n",
495 		       (u64)TCOBASE);
496 		ret = -EBUSY;
497 		goto unreg_smi;
498 	}
499 
500 	pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
501 		ich_info->name, ich_info->iTCO_version, (u64)TCOBASE);
502 
503 	/* Clear out the (probably old) status */
504 	if (iTCO_wdt_private.iTCO_version == 3) {
505 		outl(0x20008, TCO1_STS);
506 	} else {
507 		outw(0x0008, TCO1_STS);	/* Clear the Time Out Status bit */
508 		outw(0x0002, TCO2_STS);	/* Clear SECOND_TO_STS bit */
509 		outw(0x0004, TCO2_STS);	/* Clear BOOT_STS bit */
510 	}
511 
512 	iTCO_wdt_watchdog_dev.bootstatus = 0;
513 	iTCO_wdt_watchdog_dev.timeout = WATCHDOG_TIMEOUT;
514 	watchdog_set_nowayout(&iTCO_wdt_watchdog_dev, nowayout);
515 	iTCO_wdt_watchdog_dev.parent = &dev->dev;
516 
517 	/* Make sure the watchdog is not running */
518 	iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
519 
520 	/* Check that the heartbeat value is within it's range;
521 	   if not reset to the default */
522 	if (iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, heartbeat)) {
523 		iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, WATCHDOG_TIMEOUT);
524 		pr_info("timeout value out of range, using %d\n",
525 			WATCHDOG_TIMEOUT);
526 	}
527 
528 	ret = watchdog_register_device(&iTCO_wdt_watchdog_dev);
529 	if (ret != 0) {
530 		pr_err("cannot register watchdog device (err=%d)\n", ret);
531 		goto unreg_tco;
532 	}
533 
534 	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
535 		heartbeat, nowayout);
536 
537 	return 0;
538 
539 unreg_tco:
540 	release_region(iTCO_wdt_private.tco_res->start,
541 			resource_size(iTCO_wdt_private.tco_res));
542 unreg_smi:
543 	release_region(iTCO_wdt_private.smi_res->start,
544 			resource_size(iTCO_wdt_private.smi_res));
545 unmap_gcs_pmc:
546 	if (iTCO_wdt_private.iTCO_version >= 2)
547 		iounmap(iTCO_wdt_private.gcs_pmc);
548 unreg_gcs_pmc:
549 	if (iTCO_wdt_private.iTCO_version >= 2)
550 		release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
551 				resource_size(iTCO_wdt_private.gcs_pmc_res));
552 out:
553 	iTCO_wdt_private.tco_res = NULL;
554 	iTCO_wdt_private.smi_res = NULL;
555 	iTCO_wdt_private.gcs_pmc_res = NULL;
556 	iTCO_wdt_private.gcs_pmc = NULL;
557 
558 	return ret;
559 }
560 
561 static int iTCO_wdt_remove(struct platform_device *dev)
562 {
563 	if (iTCO_wdt_private.tco_res || iTCO_wdt_private.smi_res)
564 		iTCO_wdt_cleanup();
565 
566 	return 0;
567 }
568 
569 static void iTCO_wdt_shutdown(struct platform_device *dev)
570 {
571 	iTCO_wdt_stop(NULL);
572 }
573 
574 static struct platform_driver iTCO_wdt_driver = {
575 	.probe          = iTCO_wdt_probe,
576 	.remove         = iTCO_wdt_remove,
577 	.shutdown       = iTCO_wdt_shutdown,
578 	.driver         = {
579 		.owner  = THIS_MODULE,
580 		.name   = DRV_NAME,
581 	},
582 };
583 
584 static int __init iTCO_wdt_init_module(void)
585 {
586 	int err;
587 
588 	pr_info("Intel TCO WatchDog Timer Driver v%s\n", DRV_VERSION);
589 
590 	err = platform_driver_register(&iTCO_wdt_driver);
591 	if (err)
592 		return err;
593 
594 	return 0;
595 }
596 
597 static void __exit iTCO_wdt_cleanup_module(void)
598 {
599 	platform_driver_unregister(&iTCO_wdt_driver);
600 	pr_info("Watchdog Module Unloaded\n");
601 }
602 
603 module_init(iTCO_wdt_init_module);
604 module_exit(iTCO_wdt_cleanup_module);
605 
606 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
607 MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
608 MODULE_VERSION(DRV_VERSION);
609 MODULE_LICENSE("GPL");
610 MODULE_ALIAS("platform:" DRV_NAME);
611