Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / drivers / watchdog / sch311x_wdt.c
1 /*
2  *      sch311x_wdt.c - Driver for the SCH311x Super-I/O chips
3  *                      integrated watchdog.
4  *
5  *      (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
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 Wim Van Sebroeck nor Iguana vzw. admit liability nor
13  *      provide warranty for any of this software. This material is
14  *      provided "AS-IS" and at no charge.
15  */
16
17 /*
18  *      Includes, defines, variables, module parameters, ...
19  */
20
21 /* Includes */
22 #include <linux/module.h>               /* For module specific items */
23 #include <linux/moduleparam.h>          /* For new moduleparam's */
24 #include <linux/types.h>                /* For standard types (like size_t) */
25 #include <linux/errno.h>                /* For the -ENODEV/... values */
26 #include <linux/kernel.h>               /* For printk/... */
27 #include <linux/miscdevice.h>           /* For MODULE_ALIAS_MISCDEV
28                                                         (WATCHDOG_MINOR) */
29 #include <linux/watchdog.h>             /* For the watchdog specific items */
30 #include <linux/init.h>                 /* For __init/__exit/... */
31 #include <linux/fs.h>                   /* For file operations */
32 #include <linux/platform_device.h>      /* For platform_driver framework */
33 #include <linux/ioport.h>               /* For io-port access */
34 #include <linux/spinlock.h>             /* For spin_lock/spin_unlock/... */
35 #include <linux/uaccess.h>              /* For copy_to_user/put_user/... */
36 #include <linux/io.h>                   /* For inb/outb/... */
37
38 /* Module and version information */
39 #define DRV_NAME        "sch311x_wdt"
40 #define PFX             DRV_NAME ": "
41
42 /* Runtime registers */
43 #define RESGEN                  0x1d
44 #define GP60                    0x47
45 #define WDT_TIME_OUT            0x65
46 #define WDT_VAL                 0x66
47 #define WDT_CFG                 0x67
48 #define WDT_CTRL                0x68
49
50 /* internal variables */
51 static unsigned long sch311x_wdt_is_open;
52 static char sch311x_wdt_expect_close;
53 static struct platform_device *sch311x_wdt_pdev;
54
55 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 };
56
57 static struct { /* The devices private data */
58         /* the Runtime Register base address */
59         unsigned short runtime_reg;
60         /* The card's boot status */
61         int boot_status;
62         /* the lock for io operations */
63         spinlock_t io_lock;
64 } sch311x_wdt_data;
65
66 /* Module load parameters */
67 static unsigned short force_id;
68 module_param(force_id, ushort, 0);
69 MODULE_PARM_DESC(force_id, "Override the detected device ID");
70
71 static unsigned short therm_trip;
72 module_param(therm_trip, ushort, 0);
73 MODULE_PARM_DESC(therm_trip, "Should a ThermTrip trigger the reset generator");
74
75 #define WATCHDOG_TIMEOUT 60             /* 60 sec default timeout */
76 static int timeout = WATCHDOG_TIMEOUT;  /* in seconds */
77 module_param(timeout, int, 0);
78 MODULE_PARM_DESC(timeout,
79         "Watchdog timeout in seconds. 1<= timeout <=15300, default="
80                 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
81
82 static int nowayout = WATCHDOG_NOWAYOUT;
83 module_param(nowayout, int, 0);
84 MODULE_PARM_DESC(nowayout,
85         "Watchdog cannot be stopped once started (default="
86                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
87
88 /*
89  *      Super-IO functions
90  */
91
92 static inline void sch311x_sio_enter(int sio_config_port)
93 {
94         outb(0x55, sio_config_port);
95 }
96
97 static inline void sch311x_sio_exit(int sio_config_port)
98 {
99         outb(0xaa, sio_config_port);
100 }
101
102 static inline int sch311x_sio_inb(int sio_config_port, int reg)
103 {
104         outb(reg, sio_config_port);
105         return inb(sio_config_port + 1);
106 }
107
108 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
109 {
110         outb(reg, sio_config_port);
111         outb(val, sio_config_port + 1);
112 }
113
114 /*
115  *      Watchdog Operations
116  */
117
118 static void sch311x_wdt_set_timeout(int t)
119 {
120         unsigned char timeout_unit = 0x80;
121
122         /* When new timeout is bigger then 255 seconds, we will use minutes */
123         if (t > 255) {
124                 timeout_unit = 0;
125                 t /= 60;
126         }
127
128         /* -- Watchdog Timeout --
129          * Bit 0-6 (Reserved)
130          * Bit 7   WDT Time-out Value Units Select
131          *         (0 = Minutes, 1 = Seconds)
132          */
133         outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT);
134
135         /* -- Watchdog Timer Time-out Value --
136          * Bit 0-7 Binary coded units (0=Disabled, 1..255)
137          */
138         outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL);
139 }
140
141 static void sch311x_wdt_start(void)
142 {
143         spin_lock(&sch311x_wdt_data.io_lock);
144
145         /* set watchdog's timeout */
146         sch311x_wdt_set_timeout(timeout);
147         /* enable the watchdog */
148         /* -- General Purpose I/O Bit 6.0 --
149          * Bit 0,   In/Out: 0 = Output, 1 = Input
150          * Bit 1,   Polarity: 0 = No Invert, 1 = Invert
151          * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT,
152          *                           10 = Either Edge Triggered Intr.4
153          * Bit 4-6  (Reserved)
154          * Bit 7,   Output Type: 0 = Push Pull Bit, 1 = Open Drain
155          */
156         outb(0x0e, sch311x_wdt_data.runtime_reg + GP60);
157
158         spin_unlock(&sch311x_wdt_data.io_lock);
159
160 }
161
162 static void sch311x_wdt_stop(void)
163 {
164         spin_lock(&sch311x_wdt_data.io_lock);
165
166         /* stop the watchdog */
167         outb(0x01, sch311x_wdt_data.runtime_reg + GP60);
168         /* disable timeout by setting it to 0 */
169         sch311x_wdt_set_timeout(0);
170
171         spin_unlock(&sch311x_wdt_data.io_lock);
172 }
173
174 static void sch311x_wdt_keepalive(void)
175 {
176         spin_lock(&sch311x_wdt_data.io_lock);
177         sch311x_wdt_set_timeout(timeout);
178         spin_unlock(&sch311x_wdt_data.io_lock);
179 }
180
181 static int sch311x_wdt_set_heartbeat(int t)
182 {
183         if (t < 1 || t > (255*60))
184                 return -EINVAL;
185
186         /* When new timeout is bigger then 255 seconds,
187          * we will round up to minutes (with a max of 255) */
188         if (t > 255)
189                 t = (((t - 1) / 60) + 1) * 60;
190
191         timeout = t;
192         return 0;
193 }
194
195 static void sch311x_wdt_get_status(int *status)
196 {
197         unsigned char new_status;
198
199         *status = 0;
200
201         spin_lock(&sch311x_wdt_data.io_lock);
202
203         /* -- Watchdog timer control --
204          * Bit 0   Status Bit: 0 = Timer counting, 1 = Timeout occured
205          * Bit 1   Reserved
206          * Bit 2   Force Timeout: 1 = Forces WD timeout event (self-cleaning)
207          * Bit 3   P20 Force Timeout enabled:
208          *          0 = P20 activity does not generate the WD timeout event
209          *          1 = P20 Allows rising edge of P20, from the keyboard
210          *              controller, to force the WD timeout event.
211          * Bit 4-7 Reserved
212          */
213         new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL);
214         if (new_status & 0x01)
215                 *status |= WDIOF_CARDRESET;
216
217         spin_unlock(&sch311x_wdt_data.io_lock);
218 }
219
220 /*
221  *      /dev/watchdog handling
222  */
223
224 static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf,
225                                                 size_t count, loff_t *ppos)
226 {
227         if (count) {
228                 if (!nowayout) {
229                         size_t i;
230
231                         sch311x_wdt_expect_close = 0;
232
233                         for (i = 0; i != count; i++) {
234                                 char c;
235                                 if (get_user(c, buf + i))
236                                         return -EFAULT;
237                                 if (c == 'V')
238                                         sch311x_wdt_expect_close = 42;
239                         }
240                 }
241                 sch311x_wdt_keepalive();
242         }
243         return count;
244 }
245
246 static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd,
247                                                         unsigned long arg)
248 {
249         int status;
250         int new_timeout;
251         void __user *argp = (void __user *)arg;
252         int __user *p = argp;
253         static struct watchdog_info ident = {
254                 .options                = WDIOF_KEEPALIVEPING |
255                                           WDIOF_SETTIMEOUT |
256                                           WDIOF_MAGICCLOSE,
257                 .firmware_version       = 1,
258                 .identity               = DRV_NAME,
259         };
260
261         switch (cmd) {
262         case WDIOC_GETSUPPORT:
263                 if (copy_to_user(argp, &ident, sizeof(ident)))
264                         return -EFAULT;
265                 break;
266
267         case WDIOC_GETSTATUS:
268         {
269                 sch311x_wdt_get_status(&status);
270                 return put_user(status, p);
271         }
272         case WDIOC_GETBOOTSTATUS:
273                 return put_user(sch311x_wdt_data.boot_status, p);
274
275         case WDIOC_SETOPTIONS:
276         {
277                 int options, retval = -EINVAL;
278
279                 if (get_user(options, p))
280                         return -EFAULT;
281                 if (options & WDIOS_DISABLECARD) {
282                         sch311x_wdt_stop();
283                         retval = 0;
284                 }
285                 if (options & WDIOS_ENABLECARD) {
286                         sch311x_wdt_start();
287                         retval = 0;
288                 }
289                 return retval;
290         }
291         case WDIOC_KEEPALIVE:
292                 sch311x_wdt_keepalive();
293                 break;
294
295         case WDIOC_SETTIMEOUT:
296                 if (get_user(new_timeout, p))
297                         return -EFAULT;
298                 if (sch311x_wdt_set_heartbeat(new_timeout))
299                         return -EINVAL;
300                 sch311x_wdt_keepalive();
301                 /* Fall */
302         case WDIOC_GETTIMEOUT:
303                 return put_user(timeout, p);
304         default:
305                 return -ENOTTY;
306         }
307         return 0;
308 }
309
310 static int sch311x_wdt_open(struct inode *inode, struct file *file)
311 {
312         if (test_and_set_bit(0, &sch311x_wdt_is_open))
313                 return -EBUSY;
314         /*
315          *      Activate
316          */
317         sch311x_wdt_start();
318         return nonseekable_open(inode, file);
319 }
320
321 static int sch311x_wdt_close(struct inode *inode, struct file *file)
322 {
323         if (sch311x_wdt_expect_close == 42) {
324                 sch311x_wdt_stop();
325         } else {
326                 printk(KERN_CRIT PFX
327                                 "Unexpected close, not stopping watchdog!\n");
328                 sch311x_wdt_keepalive();
329         }
330         clear_bit(0, &sch311x_wdt_is_open);
331         sch311x_wdt_expect_close = 0;
332         return 0;
333 }
334
335 /*
336  *      Kernel Interfaces
337  */
338
339 static const struct file_operations sch311x_wdt_fops = {
340         .owner          = THIS_MODULE,
341         .llseek         = no_llseek,
342         .write          = sch311x_wdt_write,
343         .unlocked_ioctl = sch311x_wdt_ioctl,
344         .open           = sch311x_wdt_open,
345         .release        = sch311x_wdt_close,
346 };
347
348 static struct miscdevice sch311x_wdt_miscdev = {
349         .minor  = WATCHDOG_MINOR,
350         .name   = "watchdog",
351         .fops   = &sch311x_wdt_fops,
352 };
353
354 /*
355  *      Init & exit routines
356  */
357
358 static int __devinit sch311x_wdt_probe(struct platform_device *pdev)
359 {
360         struct device *dev = &pdev->dev;
361         unsigned char val;
362         int err;
363
364         spin_lock_init(&sch311x_wdt_data.io_lock);
365
366         if (!request_region(sch311x_wdt_data.runtime_reg + RESGEN, 1,
367                                                                 DRV_NAME)) {
368                 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
369                         sch311x_wdt_data.runtime_reg + RESGEN,
370                         sch311x_wdt_data.runtime_reg + RESGEN);
371                 err = -EBUSY;
372                 goto exit;
373         }
374
375         if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) {
376                 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
377                         sch311x_wdt_data.runtime_reg + GP60,
378                         sch311x_wdt_data.runtime_reg + GP60);
379                 err = -EBUSY;
380                 goto exit_release_region;
381         }
382
383         if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4,
384                                                                 DRV_NAME)) {
385                 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
386                         sch311x_wdt_data.runtime_reg + WDT_TIME_OUT,
387                         sch311x_wdt_data.runtime_reg + WDT_CTRL);
388                 err = -EBUSY;
389                 goto exit_release_region2;
390         }
391
392         /* Make sure that the watchdog is not running */
393         sch311x_wdt_stop();
394
395         /* Disable keyboard and mouse interaction and interrupt */
396         /* -- Watchdog timer configuration --
397          * Bit 0   Reserved
398          * Bit 1   Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.
399          * Bit 2   Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr
400          * Bit 3   Reserved
401          * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,
402          *            0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15)
403          */
404         outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG);
405
406         /* Check that the heartbeat value is within it's range ;
407          * if not reset to the default */
408         if (sch311x_wdt_set_heartbeat(timeout)) {
409                 sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT);
410                 dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n",
411                         timeout);
412         }
413
414         /* Get status at boot */
415         sch311x_wdt_get_status(&sch311x_wdt_data.boot_status);
416
417         /* enable watchdog */
418         /* -- Reset Generator --
419          * Bit 0   Enable Watchdog Timer Generation: 0* = Enabled, 1 = Disabled
420          * Bit 1   Thermtrip Source Select: O* = No Source, 1 = Source
421          * Bit 2   WDT2_CTL: WDT input bit
422          * Bit 3-7 Reserved
423          */
424         outb(0, sch311x_wdt_data.runtime_reg + RESGEN);
425         val = therm_trip ? 0x06 : 0x04;
426         outb(val, sch311x_wdt_data.runtime_reg + RESGEN);
427
428         err = misc_register(&sch311x_wdt_miscdev);
429         if (err != 0) {
430                 dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
431                                                         WATCHDOG_MINOR, err);
432                 goto exit_release_region3;
433         }
434
435         sch311x_wdt_miscdev.parent = dev;
436
437         dev_info(dev,
438                 "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n",
439                 timeout, nowayout);
440
441         return 0;
442
443 exit_release_region3:
444         release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
445 exit_release_region2:
446         release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
447 exit_release_region:
448         release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
449         sch311x_wdt_data.runtime_reg = 0;
450 exit:
451         return err;
452 }
453
454 static int __devexit sch311x_wdt_remove(struct platform_device *pdev)
455 {
456         /* Stop the timer before we leave */
457         if (!nowayout)
458                 sch311x_wdt_stop();
459
460         /* Deregister */
461         misc_deregister(&sch311x_wdt_miscdev);
462         release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
463         release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
464         release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
465         sch311x_wdt_data.runtime_reg = 0;
466         return 0;
467 }
468
469 static void sch311x_wdt_shutdown(struct platform_device *dev)
470 {
471         /* Turn the WDT off if we have a soft shutdown */
472         sch311x_wdt_stop();
473 }
474
475 #define sch311x_wdt_suspend NULL
476 #define sch311x_wdt_resume  NULL
477
478 static struct platform_driver sch311x_wdt_driver = {
479         .probe          = sch311x_wdt_probe,
480         .remove         = __devexit_p(sch311x_wdt_remove),
481         .shutdown       = sch311x_wdt_shutdown,
482         .suspend        = sch311x_wdt_suspend,
483         .resume         = sch311x_wdt_resume,
484         .driver         = {
485                 .owner = THIS_MODULE,
486                 .name = DRV_NAME,
487         },
488 };
489
490 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
491 {
492         int err = 0, reg;
493         unsigned short base_addr;
494         unsigned char dev_id;
495
496         sch311x_sio_enter(sio_config_port);
497
498         /* Check device ID. We currently know about:
499          * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
500         reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20);
501         if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
502                 err = -ENODEV;
503                 goto exit;
504         }
505         dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
506
507         /* Select logical device A (runtime registers) */
508         sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
509
510         /* Check if Logical Device Register is currently active */
511         if (sch311x_sio_inb(sio_config_port, 0x30) && 0x01 == 0)
512                 printk(KERN_INFO PFX "Seems that LDN 0x0a is not active...\n");
513
514         /* Get the base address of the runtime registers */
515         base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
516                            sch311x_sio_inb(sio_config_port, 0x61);
517         if (!base_addr) {
518                 printk(KERN_ERR PFX "Base address not set.\n");
519                 err = -ENODEV;
520                 goto exit;
521         }
522         *addr = base_addr;
523
524         printk(KERN_INFO PFX "Found an SMSC SCH311%d chip at 0x%04x\n",
525                 dev_id, base_addr);
526
527 exit:
528         sch311x_sio_exit(sio_config_port);
529         return err;
530 }
531
532 static int __init sch311x_wdt_init(void)
533 {
534         int err, i, found = 0;
535         unsigned short addr = 0;
536
537         for (i = 0; !found && sch311x_ioports[i]; i++)
538                 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
539                         found++;
540
541         if (!found)
542                 return -ENODEV;
543
544         sch311x_wdt_data.runtime_reg = addr;
545
546         err = platform_driver_register(&sch311x_wdt_driver);
547         if (err)
548                 return err;
549
550         sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr,
551                                                                 NULL, 0);
552
553         if (IS_ERR(sch311x_wdt_pdev)) {
554                 err = PTR_ERR(sch311x_wdt_pdev);
555                 goto unreg_platform_driver;
556         }
557
558         return 0;
559
560 unreg_platform_driver:
561         platform_driver_unregister(&sch311x_wdt_driver);
562         return err;
563 }
564
565 static void __exit sch311x_wdt_exit(void)
566 {
567         platform_device_unregister(sch311x_wdt_pdev);
568         platform_driver_unregister(&sch311x_wdt_driver);
569 }
570
571 module_init(sch311x_wdt_init);
572 module_exit(sch311x_wdt_exit);
573
574 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
575 MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver");
576 MODULE_LICENSE("GPL");
577 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
578