blob: 084dfe9cecfb617575f5c82bc770aaa69db972b3 [file] [log] [blame]
David S. Miller8ab0dc32008-08-29 17:07:01 -07001/* cpwd.c - driver implementation for hardware watchdog
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * timers found on Sun Microsystems CP1400 and CP1500 boards.
3 *
4 * This device supports both the generic Linux watchdog
5 * interface and Solaris-compatible ioctls as best it is
6 * able.
7 *
8 * NOTE: CP1400 systems appear to have a defective intr_mask
9 * register on the PLD, preventing the disabling of
10 * timer interrupts. We use a timer to periodically
11 * reset 'stopped' watchdogs on affected platforms.
12 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * Copyright (c) 2000 Eric Brower (ebrower@usa.net)
David S. Millerc5f85562008-08-29 17:05:51 -070014 * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015 */
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/fs.h>
20#include <linux/errno.h>
21#include <linux/major.h>
22#include <linux/init.h>
23#include <linux/miscdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/interrupt.h>
25#include <linux/ioport.h>
26#include <linux/timer.h>
Christoph Hellwigb66621f2005-11-07 14:13:14 -080027#include <linux/smp_lock.h>
Andrew Morton347e03d2007-07-15 23:42:03 -070028#include <linux/io.h>
David S. Millerc5f85562008-08-29 17:05:51 -070029#include <linux/of.h>
30#include <linux/of_device.h>
31
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <asm/irq.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <asm/uaccess.h>
34
35#include <asm/watchdog.h>
36
David S. Millerc5f85562008-08-29 17:05:51 -070037#define DRIVER_NAME "cpwd"
38#define PFX DRIVER_NAME ": "
39
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#define WD_OBPNAME "watchdog"
David S. Millerc5f85562008-08-29 17:05:51 -070041#define WD_BADMODEL "SUNW,501-5336"
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#define WD_BTIMEOUT (jiffies + (HZ * 1000))
43#define WD_BLIMIT 0xFFFF
44
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#define WD0_MINOR 212
46#define WD1_MINOR 213
47#define WD2_MINOR 214
48
David S. Millerc5f85562008-08-29 17:05:51 -070049/* Internal driver definitions. */
50#define WD0_ID 0
51#define WD1_ID 1
52#define WD2_ID 2
53#define WD_NUMDEVS 3
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
David S. Millerc5f85562008-08-29 17:05:51 -070055#define WD_INTR_OFF 0
56#define WD_INTR_ON 1
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58#define WD_STAT_INIT 0x01 /* Watchdog timer is initialized */
59#define WD_STAT_BSTOP 0x02 /* Watchdog timer is brokenstopped */
60#define WD_STAT_SVCD 0x04 /* Watchdog interrupt occurred */
61
62/* Register value definitions
63 */
64#define WD0_INTR_MASK 0x01 /* Watchdog device interrupt masks */
65#define WD1_INTR_MASK 0x02
66#define WD2_INTR_MASK 0x04
67
68#define WD_S_RUNNING 0x01 /* Watchdog device status running */
69#define WD_S_EXPIRED 0x02 /* Watchdog device status expired */
70
David S. Millerc5f85562008-08-29 17:05:51 -070071struct cpwd {
72 void __iomem *regs;
73 spinlock_t lock;
74
75 unsigned int irq;
76
77 unsigned long timeout;
78 bool enabled;
79 bool reboot;
80 bool broken;
81 bool initialized;
82
83 struct {
84 struct miscdevice misc;
85 void __iomem *regs;
86 u8 intr_mask;
87 u8 runstatus;
88 u16 timeout;
89 } devs[WD_NUMDEVS];
90};
91
92static struct cpwd *cpwd_device;
93
Linus Torvalds1da177e2005-04-16 15:20:36 -070094/* Sun uses Altera PLD EPF8820ATC144-4
95 * providing three hardware watchdogs:
96 *
97 * 1) RIC - sends an interrupt when triggered
98 * 2) XIR - asserts XIR_B_RESET when triggered, resets CPU
99 * 3) POR - asserts POR_B_RESET when triggered, resets CPU, backplane, board
100 *
101 *** Timer register block definition (struct wd_timer_regblk)
102 *
103 * dcntr and limit registers (halfword access):
104 * -------------------
105 * | 15 | ...| 1 | 0 |
106 * -------------------
107 * |- counter val -|
108 * -------------------
109 * dcntr - Current 16-bit downcounter value.
110 * When downcounter reaches '0' watchdog expires.
111 * Reading this register resets downcounter with 'limit' value.
112 * limit - 16-bit countdown value in 1/10th second increments.
113 * Writing this register begins countdown with input value.
114 * Reading from this register does not affect counter.
115 * NOTES: After watchdog reset, dcntr and limit contain '1'
116 *
117 * status register (byte access):
118 * ---------------------------
119 * | 7 | ... | 2 | 1 | 0 |
120 * --------------+------------
121 * |- UNUSED -| EXP | RUN |
122 * ---------------------------
123 * status- Bit 0 - Watchdog is running
124 * Bit 1 - Watchdog has expired
125 *
126 *** PLD register block definition (struct wd_pld_regblk)
127 *
128 * intr_mask register (byte access):
129 * ---------------------------------
130 * | 7 | ... | 3 | 2 | 1 | 0 |
131 * +-------------+------------------
132 * |- UNUSED -| WD3 | WD2 | WD1 |
133 * ---------------------------------
134 * WD3 - 1 == Interrupt disabled for watchdog 3
135 * WD2 - 1 == Interrupt disabled for watchdog 2
136 * WD1 - 1 == Interrupt disabled for watchdog 1
137 *
138 * pld_status register (byte access):
139 * UNKNOWN, MAGICAL MYSTERY REGISTER
140 *
141 */
142#define WD_TIMER_REGSZ 16
143#define WD0_OFF 0
144#define WD1_OFF (WD_TIMER_REGSZ * 1)
145#define WD2_OFF (WD_TIMER_REGSZ * 2)
146#define PLD_OFF (WD_TIMER_REGSZ * 3)
147
148#define WD_DCNTR 0x00
149#define WD_LIMIT 0x04
150#define WD_STATUS 0x08
151
152#define PLD_IMASK (PLD_OFF + 0x00)
153#define PLD_STATUS (PLD_OFF + 0x04)
154
David S. Millerc5f85562008-08-29 17:05:51 -0700155static struct timer_list cpwd_timer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
157static int wd0_timeout = 0;
158static int wd1_timeout = 0;
159static int wd2_timeout = 0;
160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161module_param (wd0_timeout, int, 0);
162MODULE_PARM_DESC(wd0_timeout, "Default watchdog0 timeout in 1/10secs");
163module_param (wd1_timeout, int, 0);
164MODULE_PARM_DESC(wd1_timeout, "Default watchdog1 timeout in 1/10secs");
165module_param (wd2_timeout, int, 0);
166MODULE_PARM_DESC(wd2_timeout, "Default watchdog2 timeout in 1/10secs");
167
David S. Millerc5f85562008-08-29 17:05:51 -0700168MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
169MODULE_DESCRIPTION("Hardware watchdog driver for Sun Microsystems CP1400/1500");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170MODULE_LICENSE("GPL");
David S. Millerc5f85562008-08-29 17:05:51 -0700171MODULE_SUPPORTED_DEVICE("watchdog");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
David S. Millerc5f85562008-08-29 17:05:51 -0700173static void cpwd_writew(u16 val, void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174{
David S. Millerc5f85562008-08-29 17:05:51 -0700175 writew(cpu_to_le16(val), addr);
176}
177static u16 cpwd_readw(void __iomem *addr)
178{
179 u16 val = readw(addr);
180
181 return le16_to_cpu(val);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182}
183
David S. Millerc5f85562008-08-29 17:05:51 -0700184static void cpwd_writeb(u8 val, void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185{
David S. Millerc5f85562008-08-29 17:05:51 -0700186 writeb(val, addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187}
188
David S. Millerc5f85562008-08-29 17:05:51 -0700189static u8 cpwd_readb(void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190{
David S. Millerc5f85562008-08-29 17:05:51 -0700191 return readb(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192}
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194/* Enable or disable watchdog interrupts
195 * Because of the CP1400 defect this should only be
196 * called during initialzation or by wd_[start|stop]timer()
197 *
David S. Millerc5f85562008-08-29 17:05:51 -0700198 * index - sub-device index, or -1 for 'all'
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 * enable - non-zero to enable interrupts, zero to disable
200 */
David S. Millerc5f85562008-08-29 17:05:51 -0700201static void cpwd_toggleintr(struct cpwd *p, int index, int enable)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202{
David S. Millerc5f85562008-08-29 17:05:51 -0700203 unsigned char curregs = cpwd_readb(p->regs + PLD_IMASK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 unsigned char setregs =
David S. Millerc5f85562008-08-29 17:05:51 -0700205 (index == -1) ?
206 (WD0_INTR_MASK | WD1_INTR_MASK | WD2_INTR_MASK) :
207 (p->devs[index].intr_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
David S. Millerc5f85562008-08-29 17:05:51 -0700209 if (enable == WD_INTR_ON)
210 curregs &= ~setregs;
211 else
212 curregs |= setregs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
David S. Millerc5f85562008-08-29 17:05:51 -0700214 cpwd_writeb(curregs, p->regs + PLD_IMASK);
215}
216
217/* Restarts timer with maximum limit value and
218 * does not unset 'brokenstop' value.
219 */
220static void cpwd_resetbrokentimer(struct cpwd *p, int index)
221{
222 cpwd_toggleintr(p, index, WD_INTR_ON);
223 cpwd_writew(WD_BLIMIT, p->devs[index].regs + WD_LIMIT);
224}
225
226/* Timer method called to reset stopped watchdogs--
227 * because of the PLD bug on CP1400, we cannot mask
228 * interrupts within the PLD so me must continually
229 * reset the timers ad infinitum.
230 */
231static void cpwd_brokentimer(unsigned long data)
232{
233 struct cpwd *p = (struct cpwd *) data;
234 int id, tripped = 0;
235
236 /* kill a running timer instance, in case we
237 * were called directly instead of by kernel timer
238 */
239 if (timer_pending(&cpwd_timer))
240 del_timer(&cpwd_timer);
241
242 for (id = 0; id < WD_NUMDEVS; id++) {
243 if (p->devs[id].runstatus & WD_STAT_BSTOP) {
244 ++tripped;
245 cpwd_resetbrokentimer(p, id);
246 }
247 }
248
249 if (tripped) {
250 /* there is at least one timer brokenstopped-- reschedule */
251 cpwd_timer.expires = WD_BTIMEOUT;
252 add_timer(&cpwd_timer);
253 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254}
255
256/* Reset countdown timer with 'limit' value and continue countdown.
257 * This will not start a stopped timer.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 */
David S. Millerc5f85562008-08-29 17:05:51 -0700259static void cpwd_pingtimer(struct cpwd *p, int index)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260{
David S. Millerc5f85562008-08-29 17:05:51 -0700261 if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING)
262 cpwd_readw(p->devs[index].regs + WD_DCNTR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263}
264
265/* Stop a running watchdog timer-- the timer actually keeps
266 * running, but the interrupt is masked so that no action is
267 * taken upon expiration.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 */
David S. Millerc5f85562008-08-29 17:05:51 -0700269static void cpwd_stoptimer(struct cpwd *p, int index)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270{
David S. Millerc5f85562008-08-29 17:05:51 -0700271 if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING) {
272 cpwd_toggleintr(p, index, WD_INTR_OFF);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
David S. Millerc5f85562008-08-29 17:05:51 -0700274 if (p->broken) {
275 p->devs[index].runstatus |= WD_STAT_BSTOP;
276 cpwd_brokentimer((unsigned long) p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 }
278 }
279}
280
281/* Start a watchdog timer with the specified limit value
282 * If the watchdog is running, it will be restarted with
283 * the provided limit value.
284 *
285 * This function will enable interrupts on the specified
286 * watchdog.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 */
David S. Millerc5f85562008-08-29 17:05:51 -0700288static void cpwd_starttimer(struct cpwd *p, int index)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289{
David S. Millerc5f85562008-08-29 17:05:51 -0700290 if (p->broken)
291 p->devs[index].runstatus &= ~WD_STAT_BSTOP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
David S. Millerc5f85562008-08-29 17:05:51 -0700293 p->devs[index].runstatus &= ~WD_STAT_SVCD;
294
295 cpwd_writew(p->devs[index].timeout, p->devs[index].regs + WD_LIMIT);
296 cpwd_toggleintr(p, index, WD_INTR_ON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297}
298
David S. Millerc5f85562008-08-29 17:05:51 -0700299static int cpwd_getstatus(struct cpwd *p, int index)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300{
David S. Millerc5f85562008-08-29 17:05:51 -0700301 unsigned char stat = cpwd_readb(p->devs[index].regs + WD_STATUS);
302 unsigned char intr = cpwd_readb(p->devs[index].regs + PLD_IMASK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 unsigned char ret = WD_STOPPED;
304
305 /* determine STOPPED */
David S. Millerc5f85562008-08-29 17:05:51 -0700306 if (!stat)
307 return ret;
308
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 /* determine EXPIRED vs FREERUN vs RUNNING */
David S. Millerc5f85562008-08-29 17:05:51 -0700310 else if (WD_S_EXPIRED & stat) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 ret = WD_EXPIRED;
David S. Millerc5f85562008-08-29 17:05:51 -0700312 } else if(WD_S_RUNNING & stat) {
313 if (intr & p->devs[index].intr_mask) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 ret = WD_FREERUN;
David S. Millerc5f85562008-08-29 17:05:51 -0700315 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 /* Fudge WD_EXPIRED status for defective CP1400--
317 * IF timer is running
318 * AND brokenstop is set
319 * AND an interrupt has been serviced
320 * we are WD_EXPIRED.
321 *
322 * IF timer is running
323 * AND brokenstop is set
324 * AND no interrupt has been serviced
325 * we are WD_FREERUN.
326 */
David S. Millerc5f85562008-08-29 17:05:51 -0700327 if (p->broken &&
328 (p->devs[index].runstatus & WD_STAT_BSTOP)) {
329 if (p->devs[index].runstatus & WD_STAT_SVCD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 ret = WD_EXPIRED;
David S. Millerc5f85562008-08-29 17:05:51 -0700331 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 /* we could as well pretend we are expired */
333 ret = WD_FREERUN;
334 }
David S. Millerc5f85562008-08-29 17:05:51 -0700335 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 ret = WD_RUNNING;
337 }
338 }
339 }
340
341 /* determine SERVICED */
David S. Millerc5f85562008-08-29 17:05:51 -0700342 if (p->devs[index].runstatus & WD_STAT_SVCD)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 ret |= WD_SERVICED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344
345 return(ret);
346}
347
David S. Millerc5f85562008-08-29 17:05:51 -0700348static irqreturn_t cpwd_interrupt(int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349{
David S. Millerc5f85562008-08-29 17:05:51 -0700350 struct cpwd *p = dev_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
David S. Millerc5f85562008-08-29 17:05:51 -0700352 /* Only WD0 will interrupt-- others are NMI and we won't
353 * see them here....
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 */
David S. Millerc5f85562008-08-29 17:05:51 -0700355 spin_lock_irq(&p->lock);
356
357 cpwd_stoptimer(p, WD0_ID);
358 p->devs[WD0_ID].runstatus |= WD_STAT_SVCD;
359
360 spin_unlock_irq(&p->lock);
361
362 return IRQ_HANDLED;
363}
364
365static int cpwd_open(struct inode *inode, struct file *f)
366{
367 struct cpwd *p = cpwd_device;
368
369 lock_kernel();
370 switch(iminor(inode)) {
371 case WD0_MINOR:
372 case WD1_MINOR:
373 case WD2_MINOR:
374 break;
375
376 default:
377 unlock_kernel();
378 return -ENODEV;
379 }
380
381 /* Register IRQ on first open of device */
382 if (!p->initialized) {
383 if (request_irq(p->irq, &cpwd_interrupt,
384 IRQF_SHARED, DRIVER_NAME, p)) {
385 printk(KERN_ERR PFX "Cannot register IRQ %d\n",
386 p->irq);
387 unlock_kernel();
388 return -EBUSY;
389 }
390 p->initialized = true;
391 }
392
393 unlock_kernel();
394
395 return nonseekable_open(inode, f);
396}
397
398static int cpwd_release(struct inode *inode, struct file *file)
399{
400 return 0;
401}
402
403static int cpwd_ioctl(struct inode *inode, struct file *file,
404 unsigned int cmd, unsigned long arg)
405{
406 static struct watchdog_info info = {
407 .options = WDIOF_SETTIMEOUT,
408 .firmware_version = 1,
409 .identity = DRIVER_NAME,
410 };
411 void __user *argp = (void __user *)arg;
412 int index = iminor(inode) - WD0_MINOR;
413 struct cpwd *p = cpwd_device;
414 int setopt = 0;
415
416 switch (cmd) {
417 /* Generic Linux IOCTLs */
418 case WDIOC_GETSUPPORT:
419 if (copy_to_user(argp, &info, sizeof(struct watchdog_info)))
420 return -EFAULT;
421 break;
422
423 case WDIOC_GETSTATUS:
424 case WDIOC_GETBOOTSTATUS:
425 if (put_user(0, (int __user *)argp))
426 return -EFAULT;
427 break;
428
429 case WDIOC_KEEPALIVE:
430 cpwd_pingtimer(p, index);
431 break;
432
433 case WDIOC_SETOPTIONS:
434 if (copy_from_user(&setopt, argp, sizeof(unsigned int)))
435 return -EFAULT;
436
437 if (setopt & WDIOS_DISABLECARD) {
438 if (p->enabled)
439 return -EINVAL;
440 cpwd_stoptimer(p, index);
441 } else if (setopt & WDIOS_ENABLECARD) {
442 cpwd_starttimer(p, index);
443 } else {
444 return -EINVAL;
445 }
446 break;
447
448 /* Solaris-compatible IOCTLs */
449 case WIOCGSTAT:
450 setopt = cpwd_getstatus(p, index);
451 if (copy_to_user(argp, &setopt, sizeof(unsigned int)))
452 return -EFAULT;
453 break;
454
455 case WIOCSTART:
456 cpwd_starttimer(p, index);
457 break;
458
459 case WIOCSTOP:
460 if (p->enabled)
461 return(-EINVAL);
462
463 cpwd_stoptimer(p, index);
464 break;
465
466 default:
467 return -EINVAL;
468 }
469
470 return 0;
471}
472
473static long cpwd_compat_ioctl(struct file *file, unsigned int cmd,
474 unsigned long arg)
475{
476 int rval = -ENOIOCTLCMD;
477
478 switch (cmd) {
479 /* solaris ioctls are specific to this driver */
480 case WIOCSTART:
481 case WIOCSTOP:
482 case WIOCGSTAT:
483 lock_kernel();
484 rval = cpwd_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
485 unlock_kernel();
486 break;
487
488 /* everything else is handled by the generic compat layer */
489 default:
490 break;
491 }
492
493 return rval;
494}
495
496static ssize_t cpwd_write(struct file *file, const char __user *buf,
497 size_t count, loff_t *ppos)
498{
499 struct inode *inode = file->f_path.dentry->d_inode;
500 struct cpwd *p = cpwd_device;
501 int index = iminor(inode);
502
503 if (count) {
504 cpwd_pingtimer(p, index);
505 return 1;
506 }
507
508 return 0;
509}
510
511static ssize_t cpwd_read(struct file * file, char __user *buffer,
512 size_t count, loff_t *ppos)
513{
514 return -EINVAL;
515}
516
517static const struct file_operations cpwd_fops = {
518 .owner = THIS_MODULE,
519 .ioctl = cpwd_ioctl,
520 .compat_ioctl = cpwd_compat_ioctl,
521 .open = cpwd_open,
522 .write = cpwd_write,
523 .read = cpwd_read,
524 .release = cpwd_release,
525};
526
527static int __devinit cpwd_probe(struct of_device *op,
528 const struct of_device_id *match)
529{
530 struct device_node *options;
531 const char *str_prop;
532 const void *prop_val;
533 int i, err = -EINVAL;
534 struct cpwd *p;
535
536 if (cpwd_device)
537 return -EINVAL;
538
539 p = kzalloc(sizeof(*p), GFP_KERNEL);
540 err = -ENOMEM;
541 if (!p) {
542 printk(KERN_ERR PFX "Unable to allocate struct cpwd.\n");
543 goto out;
544 }
545
546 p->irq = op->irqs[0];
547
548 spin_lock_init(&p->lock);
549
550 p->regs = of_ioremap(&op->resource[0], 0,
551 4 * WD_TIMER_REGSZ, DRIVER_NAME);
552 if (!p->regs) {
553 printk(KERN_ERR PFX "Unable to map registers.\n");
554 goto out_free;
555 }
556
557 options = of_find_node_by_path("/options");
558 err = -ENODEV;
559 if (!options) {
560 printk(KERN_ERR PFX "Unable to find /options node.\n");
561 goto out_iounmap;
562 }
563
564 prop_val = of_get_property(options, "watchdog-enable?", NULL);
565 p->enabled = (prop_val ? true : false);
566
567 prop_val = of_get_property(options, "watchdog-reboot?", NULL);
568 p->reboot = (prop_val ? true : false);
569
570 str_prop = of_get_property(options, "watchdog-timeout", NULL);
571 if (str_prop)
572 p->timeout = simple_strtoul(str_prop, NULL, 10);
573
574 /* CP1400s seem to have broken PLD implementations-- the
575 * interrupt_mask register cannot be written, so no timer
576 * interrupts can be masked within the PLD.
577 */
578 str_prop = of_get_property(op->node, "model", NULL);
579 p->broken = (str_prop && !strcmp(str_prop, WD_BADMODEL));
580
581 if (!p->enabled)
582 cpwd_toggleintr(p, -1, WD_INTR_OFF);
583
584 for (i = 0; i < WD_NUMDEVS; i++) {
585 static const char *cpwd_names[] = { "RIC", "XIR", "POR" };
586 static int *parms[] = { &wd0_timeout,
587 &wd1_timeout,
588 &wd2_timeout };
589 struct miscdevice *mp = &p->devs[i].misc;
590
591 mp->minor = WD0_MINOR + i;
592 mp->name = cpwd_names[i];
593 mp->fops = &cpwd_fops;
594
595 p->devs[i].regs = p->regs + (i * WD_TIMER_REGSZ);
596 p->devs[i].intr_mask = (WD0_INTR_MASK << i);
597 p->devs[i].runstatus &= ~WD_STAT_BSTOP;
598 p->devs[i].runstatus |= WD_STAT_INIT;
599 p->devs[i].timeout = p->timeout;
600 if (*parms[i])
601 p->devs[i].timeout = *parms[i];
602
603 err = misc_register(&p->devs[i].misc);
604 if (err) {
605 printk(KERN_ERR "Could not register misc device for "
606 "dev %d\n", i);
607 goto out_unregister;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 }
609 }
610
David S. Millerc5f85562008-08-29 17:05:51 -0700611 if (p->broken) {
612 init_timer(&cpwd_timer);
613 cpwd_timer.function = cpwd_brokentimer;
614 cpwd_timer.data = (unsigned long) p;
615 cpwd_timer.expires = WD_BTIMEOUT;
616
617 printk(KERN_INFO PFX "PLD defect workaround enabled for "
618 "model " WD_BADMODEL ".\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 }
David S. Millerc5f85562008-08-29 17:05:51 -0700620
621 dev_set_drvdata(&op->dev, p);
622 cpwd_device = p;
623 err = 0;
624
625out:
626 return err;
627
628out_unregister:
629 for (i--; i >= 0; i--)
630 misc_deregister(&p->devs[i].misc);
631
632out_iounmap:
633 of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
634
635out_free:
636 kfree(p);
637 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638}
639
David S. Millerc5f85562008-08-29 17:05:51 -0700640static int __devexit cpwd_remove(struct of_device *op)
641{
642 struct cpwd *p = dev_get_drvdata(&op->dev);
643 int i;
644
645 for (i = 0; i < 4; i++) {
646 misc_deregister(&p->devs[i].misc);
647
648 if (!p->enabled) {
649 cpwd_stoptimer(p, i);
650 if (p->devs[i].runstatus & WD_STAT_BSTOP)
651 cpwd_resetbrokentimer(p, i);
652 }
653 }
654
655 if (p->broken)
656 del_timer_sync(&cpwd_timer);
657
658 if (p->initialized)
659 free_irq(p->irq, p);
660
661 of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
662 kfree(p);
663
664 cpwd_device = NULL;
665
666 return 0;
667}
668
David S. Millerfd098312008-08-31 01:23:17 -0700669static const struct of_device_id cpwd_match[] = {
David S. Millerc5f85562008-08-29 17:05:51 -0700670 {
671 .name = "watchdog",
672 },
673 {},
674};
675MODULE_DEVICE_TABLE(of, cpwd_match);
676
677static struct of_platform_driver cpwd_driver = {
678 .name = DRIVER_NAME,
679 .match_table = cpwd_match,
680 .probe = cpwd_probe,
681 .remove = __devexit_p(cpwd_remove),
682};
683
684static int __init cpwd_init(void)
685{
686 return of_register_driver(&cpwd_driver, &of_bus_type);
687}
688
689static void __exit cpwd_exit(void)
690{
691 of_unregister_driver(&cpwd_driver);
692}
693
694module_init(cpwd_init);
695module_exit(cpwd_exit);