summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/lm78.c
blob: 51c0b37c4990e1284f4304917fc3cf714776231e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
/*
    lm78.c - Part of lm_sensors, Linux kernel modules for hardware
             monitoring
    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> 

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/i2c-isa.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <asm/io.h>

/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x20, 0x21, 0x22, 0x23, 0x24,
					0x25, 0x26, 0x27, 0x28, 0x29,
					0x2a, 0x2b, 0x2c, 0x2d, 0x2e,
					0x2f, I2C_CLIENT_END };
static unsigned short isa_address = 0x290;

/* Insmod parameters */
I2C_CLIENT_INSMOD_2(lm78, lm79);

/* Many LM78 constants specified below */

/* Length of ISA address segment */
#define LM78_EXTENT 8

/* Where are the ISA address/data registers relative to the base address */
#define LM78_ADDR_REG_OFFSET 5
#define LM78_DATA_REG_OFFSET 6

/* The LM78 registers */
#define LM78_REG_IN_MAX(nr) (0x2b + (nr) * 2)
#define LM78_REG_IN_MIN(nr) (0x2c + (nr) * 2)
#define LM78_REG_IN(nr) (0x20 + (nr))

#define LM78_REG_FAN_MIN(nr) (0x3b + (nr))
#define LM78_REG_FAN(nr) (0x28 + (nr))

#define LM78_REG_TEMP 0x27
#define LM78_REG_TEMP_OVER 0x39
#define LM78_REG_TEMP_HYST 0x3a

#define LM78_REG_ALARM1 0x41
#define LM78_REG_ALARM2 0x42

#define LM78_REG_VID_FANDIV 0x47

#define LM78_REG_CONFIG 0x40
#define LM78_REG_CHIPID 0x49
#define LM78_REG_I2C_ADDR 0x48


/* Conversions. Rounding and limit checking is only done on the TO_REG 
   variants. */

/* IN: mV, (0V to 4.08V)
   REG: 16mV/bit */
static inline u8 IN_TO_REG(unsigned long val)
{
	unsigned long nval = SENSORS_LIMIT(val, 0, 4080);
	return (nval + 8) / 16;
}
#define IN_FROM_REG(val) ((val) *  16)

static inline u8 FAN_TO_REG(long rpm, int div)
{
	if (rpm <= 0)
		return 255;
	return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
}

static inline int FAN_FROM_REG(u8 val, int div)
{
	return val==0 ? -1 : val==255 ? 0 : 1350000/(val*div);
}

/* TEMP: mC (-128C to +127C)
   REG: 1C/bit, two's complement */
static inline s8 TEMP_TO_REG(int val)
{
	int nval = SENSORS_LIMIT(val, -128000, 127000) ;
	return nval<0 ? (nval-500)/1000 : (nval+500)/1000;
}

static inline int TEMP_FROM_REG(s8 val)
{
	return val * 1000;
}

/* VID: mV
   REG: (see doc/vid) */
static inline int VID_FROM_REG(u8 val)
{
	return val==0x1f ? 0 : val>=0x10 ? 5100-val*100 : 2050-val*50;
}

#define DIV_FROM_REG(val) (1 << (val))

/* There are some complications in a module like this. First off, LM78 chips
   may be both present on the SMBus and the ISA bus, and we have to handle
   those cases separately at some places. Second, there might be several
   LM78 chips available (well, actually, that is probably never done; but
   it is a clean illustration of how to handle a case like that). Finally,
   a specific chip may be attached to *both* ISA and SMBus, and we would
   not like to detect it double. Fortunately, in the case of the LM78 at
   least, a register tells us what SMBus address we are on, so that helps
   a bit - except if there could be more than one SMBus. Groan. No solution
   for this yet. */

/* This module may seem overly long and complicated. In fact, it is not so
   bad. Quite a lot of bookkeeping is done. A real driver can often cut
   some corners. */

/* For each registered LM78, we need to keep some data in memory. That
   data is pointed to by lm78_list[NR]->data. The structure itself is
   dynamically allocated, at the same time when a new lm78 client is
   allocated. */
struct lm78_data {
	struct i2c_client client;
	struct class_device *class_dev;
	struct semaphore lock;
	enum chips type;

	struct semaphore update_lock;
	char valid;		/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	u8 in[7];		/* Register value */
	u8 in_max[7];		/* Register value */
	u8 in_min[7];		/* Register value */
	u8 fan[3];		/* Register value */
	u8 fan_min[3];		/* Register value */
	s8 temp;		/* Register value */
	s8 temp_over;		/* Register value */
	s8 temp_hyst;		/* Register value */
	u8 fan_div[3];		/* Register encoding, shifted right */
	u8 vid;			/* Register encoding, combined */
	u16 alarms;		/* Register encoding, combined */
};


static int lm78_attach_adapter(struct i2c_adapter *adapter);
static int lm78_isa_attach_adapter(struct i2c_adapter *adapter);
static int lm78_detect(struct i2c_adapter *adapter, int address, int kind);
static int lm78_detach_client(struct i2c_client *client);

static int lm78_read_value(struct i2c_client *client, u8 register);
static int lm78_write_value(struct i2c_client *client, u8 register, u8 value);
static struct lm78_data *lm78_update_device(struct device *dev);
static void lm78_init_client(struct i2c_client *client);


static struct i2c_driver lm78_driver = {
	.owner		= THIS_MODULE,
	.name		= "lm78",
	.id		= I2C_DRIVERID_LM78,
	.flags		= I2C_DF_NOTIFY,
	.attach_adapter	= lm78_attach_adapter,
	.detach_client	= lm78_detach_client,
};

static struct i2c_driver lm78_isa_driver = {
	.owner		= THIS_MODULE,
	.name		= "lm78-isa",
	.attach_adapter	= lm78_isa_attach_adapter,
	.detach_client	= lm78_detach_client,
};


/* 7 Voltages */
static ssize_t show_in(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr]));
}

static ssize_t show_in_min(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr]));
}

static ssize_t show_in_max(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr]));
}

static ssize_t set_in_min(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	down(&data->update_lock);
	data->in_min[nr] = IN_TO_REG(val);
	lm78_write_value(client, LM78_REG_IN_MIN(nr), data->in_min[nr]);
	up(&data->update_lock);
	return count;
}

static ssize_t set_in_max(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	down(&data->update_lock);
	data->in_max[nr] = IN_TO_REG(val);
	lm78_write_value(client, LM78_REG_IN_MAX(nr), data->in_max[nr]);
	up(&data->update_lock);
	return count;
}
	
#define show_in_offset(offset)					\
static ssize_t							\
	show_in##offset (struct device *dev, struct device_attribute *attr, char *buf)		\
{								\
	return show_in(dev, buf, offset);			\
}								\
static DEVICE_ATTR(in##offset##_input, S_IRUGO, 		\
		show_in##offset, NULL);				\
static ssize_t							\
	show_in##offset##_min (struct device *dev, struct device_attribute *attr, char *buf)   \
{								\
	return show_in_min(dev, buf, offset);			\
}								\
static ssize_t							\
	show_in##offset##_max (struct device *dev, struct device_attribute *attr, char *buf)   \
{								\
	return show_in_max(dev, buf, offset);			\
}								\
static ssize_t set_in##offset##_min (struct device *dev, struct device_attribute *attr,	\
		const char *buf, size_t count)			\
{								\
	return set_in_min(dev, buf, count, offset);		\
}								\
static ssize_t set_in##offset##_max (struct device *dev, struct device_attribute *attr,	\
		const char *buf, size_t count)			\
{								\
	return set_in_max(dev, buf, count, offset);		\
}								\
static DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,		\
		show_in##offset##_min, set_in##offset##_min);	\
static DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,		\
		show_in##offset##_max, set_in##offset##_max);

show_in_offset(0);
show_in_offset(1);
show_in_offset(2);
show_in_offset(3);
show_in_offset(4);
show_in_offset(5);
show_in_offset(6);

/* Temperature */
static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));
}

static ssize_t show_temp_over(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over));
}

static ssize_t set_temp_over(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);

	down(&data->update_lock);
	data->temp_over = TEMP_TO_REG(val);
	lm78_write_value(client, LM78_REG_TEMP_OVER, data->temp_over);
	up(&data->update_lock);
	return count;
}

static ssize_t show_temp_hyst(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_hyst));
}

static ssize_t set_temp_hyst(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);

	down(&data->update_lock);
	data->temp_hyst = TEMP_TO_REG(val);
	lm78_write_value(client, LM78_REG_TEMP_HYST, data->temp_hyst);
	up(&data->update_lock);
	return count;
}

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
static DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
		show_temp_over, set_temp_over);
static DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR,
		show_temp_hyst, set_temp_hyst);

/* 3 Fans */
static ssize_t show_fan(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
		DIV_FROM_REG(data->fan_div[nr])) );
}

static ssize_t show_fan_min(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf,"%d\n", FAN_FROM_REG(data->fan_min[nr],
		DIV_FROM_REG(data->fan_div[nr])) );
}

static ssize_t set_fan_min(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	down(&data->update_lock);
	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
	lm78_write_value(client, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
	up(&data->update_lock);
	return count;
}

static ssize_t show_fan_div(struct device *dev, char *buf, int nr)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]) );
}

/* Note: we save and restore the fan minimum here, because its value is
   determined in part by the fan divisor.  This follows the principle of
   least suprise; the user doesn't expect the fan minimum to change just
   because the divisor changed. */
static ssize_t set_fan_div(struct device *dev, const char *buf,
	size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	unsigned long val = simple_strtoul(buf, NULL, 10);
	unsigned long min;
	u8 reg;

	down(&data->update_lock);
	min = FAN_FROM_REG(data->fan_min[nr],
			   DIV_FROM_REG(data->fan_div[nr]));

	switch (val) {
	case 1: data->fan_div[nr] = 0; break;
	case 2: data->fan_div[nr] = 1; break;
	case 4: data->fan_div[nr] = 2; break;
	case 8: data->fan_div[nr] = 3; break;
	default:
		dev_err(&client->dev, "fan_div value %ld not "
			"supported. Choose one of 1, 2, 4 or 8!\n", val);
		up(&data->update_lock);
		return -EINVAL;
	}

	reg = lm78_read_value(client, LM78_REG_VID_FANDIV);
	switch (nr) {
	case 0:
		reg = (reg & 0xcf) | (data->fan_div[nr] << 4);
		break;
	case 1:
		reg = (reg & 0x3f) | (data->fan_div[nr] << 6);
		break;
	}
	lm78_write_value(client, LM78_REG_VID_FANDIV, reg);

	data->fan_min[nr] =
		FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
	lm78_write_value(client, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
	up(&data->update_lock);

	return count;
}

#define show_fan_offset(offset)						\
static ssize_t show_fan_##offset (struct device *dev, struct device_attribute *attr, char *buf)	\
{									\
	return show_fan(dev, buf, offset - 1);				\
}									\
static ssize_t show_fan_##offset##_min (struct device *dev, struct device_attribute *attr, char *buf)  \
{									\
	return show_fan_min(dev, buf, offset - 1);			\
}									\
static ssize_t show_fan_##offset##_div (struct device *dev, struct device_attribute *attr, char *buf)  \
{									\
	return show_fan_div(dev, buf, offset - 1);			\
}									\
static ssize_t set_fan_##offset##_min (struct device *dev, struct device_attribute *attr,		\
		const char *buf, size_t count)				\
{									\
	return set_fan_min(dev, buf, count, offset - 1);		\
}									\
static DEVICE_ATTR(fan##offset##_input, S_IRUGO, show_fan_##offset, NULL);\
static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
		show_fan_##offset##_min, set_fan_##offset##_min);

static ssize_t set_fan_1_div(struct device *dev, struct device_attribute *attr, const char *buf,
		size_t count)
{
	return set_fan_div(dev, buf, count, 0) ;
}

static ssize_t set_fan_2_div(struct device *dev, struct device_attribute *attr, const char *buf,
		size_t count)
{
	return set_fan_div(dev, buf, count, 1) ;
}

show_fan_offset(1);
show_fan_offset(2);
show_fan_offset(3);

/* Fan 3 divisor is locked in H/W */
static DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR,
		show_fan_1_div, set_fan_1_div);
static DEVICE_ATTR(fan2_div, S_IRUGO | S_IWUSR,
		show_fan_2_div, set_fan_2_div);
static DEVICE_ATTR(fan3_div, S_IRUGO, show_fan_3_div, NULL);

/* VID */
static ssize_t show_vid(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%d\n", VID_FROM_REG(data->vid));
}
static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);

/* Alarms */
static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm78_data *data = lm78_update_device(dev);
	return sprintf(buf, "%u\n", data->alarms);
}
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);

/* This function is called when:
     * lm78_driver is inserted (when this module is loaded), for each
       available adapter
     * when a new adapter is inserted (and lm78_driver is still present) */
static int lm78_attach_adapter(struct i2c_adapter *adapter)
{
	if (!(adapter->class & I2C_CLASS_HWMON))
		return 0;
	return i2c_probe(adapter, &addr_data, lm78_detect);
}

static int lm78_isa_attach_adapter(struct i2c_adapter *adapter)
{
	return lm78_detect(adapter, isa_address, -1);
}

/* This function is called by i2c_probe */
int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
{
	int i, err;
	struct i2c_client *new_client;
	struct lm78_data *data;
	const char *client_name = "";
	int is_isa = i2c_is_isa_adapter(adapter);

	if (!is_isa &&
	    !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
		err = -ENODEV;
		goto ERROR0;
	}

	/* Reserve the ISA region */
	if (is_isa)
		if (!request_region(address, LM78_EXTENT,
				    lm78_isa_driver.name)) {
			err = -EBUSY;
			goto ERROR0;
		}

	/* Probe whether there is anything available on this address. Already
	   done for SMBus clients */
	if (kind < 0) {
		if (is_isa) {

#define REALLY_SLOW_IO
			/* We need the timeouts for at least some LM78-like
			   chips. But only if we read 'undefined' registers. */
			i = inb_p(address + 1);
			if (inb_p(address + 2) != i) {
				err = -ENODEV;
				goto ERROR1;
			}
			if (inb_p(address + 3) != i) {
				err = -ENODEV;
				goto ERROR1;
			}
			if (inb_p(address + 7) != i) {
				err = -ENODEV;
				goto ERROR1;
			}
#undef REALLY_SLOW_IO

			/* Let's just hope nothing breaks here */
			i = inb_p(address + 5) & 0x7f;
			outb_p(~i & 0x7f, address + 5);
			if ((inb_p(address + 5) & 0x7f) != (~i & 0x7f)) {
				outb_p(i, address + 5);
				err = -ENODEV;
				goto ERROR1;
			}
		}
	}

	/* OK. For now, we presume we have a valid client. We now create the
	   client structure, even though we cannot fill it completely yet.
	   But it allows us to access lm78_{read,write}_value. */

	if (!(data = kmalloc(sizeof(struct lm78_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto ERROR1;
	}
	memset(data, 0, sizeof(struct lm78_data));

	new_client = &data->client;
	if (is_isa)
		init_MUTEX(&data->lock);
	i2c_set_clientdata(new_client, data);
	new_client->addr = address;
	new_client->adapter = adapter;
	new_client->driver = is_isa ? &lm78_isa_driver : &lm78_driver;
	new_client->flags = 0;

	/* Now, we do the remaining detection. */
	if (kind < 0) {
		if (lm78_read_value(new_client, LM78_REG_CONFIG) & 0x80) {
			err = -ENODEV;
			goto ERROR2;
		}
		if (!is_isa && (lm78_read_value(
				new_client, LM78_REG_I2C_ADDR) != address)) {
			err = -ENODEV;
			goto ERROR2;
		}
	}

	/* Determine the chip type. */
	if (kind <= 0) {
		i = lm78_read_value(new_client, LM78_REG_CHIPID);
		if (i == 0x00 || i == 0x20	/* LM78 */
		 || i == 0x40)			/* LM78-J */
			kind = lm78;
		else if ((i & 0xfe) == 0xc0)
			kind = lm79;
		else {
			if (kind == 0)
				dev_warn(&adapter->dev, "Ignoring 'force' "
					"parameter for unknown chip at "
					"adapter %d, address 0x%02x\n",
					i2c_adapter_id(adapter), address);
			err = -ENODEV;
			goto ERROR2;
		}
	}

	if (kind == lm78) {
		client_name = "lm78";
	} else if (kind == lm79) {
		client_name = "lm79";
	}

	/* Fill in the remaining client fields and put into the global list */
	strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
	data->type = kind;

	data->valid = 0;
	init_MUTEX(&data->update_lock);

	/* Tell the I2C layer a new client has arrived */
	if ((err = i2c_attach_client(new_client)))
		goto ERROR2;

	/* Initialize the LM78 chip */
	lm78_init_client(new_client);

	/* A few vars need to be filled upon startup */
	for (i = 0; i < 3; i++) {
		data->fan_min[i] = lm78_read_value(new_client,
					LM78_REG_FAN_MIN(i));
	}

	/* Register sysfs hooks */
	data->class_dev = hwmon_device_register(&new_client->dev);
	if (IS_ERR(data->class_dev)) {
		err = PTR_ERR(data->class_dev);
		goto ERROR3;
	}

	device_create_file(&new_client->dev, &dev_attr_in0_input);
	device_create_file(&new_client->dev, &dev_attr_in0_min);
	device_create_file(&new_client->dev, &dev_attr_in0_max);
	device_create_file(&new_client->dev, &dev_attr_in1_input);
	device_create_file(&new_client->dev, &dev_attr_in1_min);
	device_create_file(&new_client->dev, &dev_attr_in1_max);
	device_create_file(&new_client->dev, &dev_attr_in2_input);
	device_create_file(&new_client->dev, &dev_attr_in2_min);
	device_create_file(&new_client->dev, &dev_attr_in2_max);
	device_create_file(&new_client->dev, &dev_attr_in3_input);
	device_create_file(&new_client->dev, &dev_attr_in3_min);
	device_create_file(&new_client->dev, &dev_attr_in3_max);
	device_create_file(&new_client->dev, &dev_attr_in4_input);
	device_create_file(&new_client->dev, &dev_attr_in4_min);
	device_create_file(&new_client->dev, &dev_attr_in4_max);
	device_create_file(&new_client->dev, &dev_attr_in5_input);
	device_create_file(&new_client->dev, &dev_attr_in5_min);
	device_create_file(&new_client->dev, &dev_attr_in5_max);
	device_create_file(&new_client->dev, &dev_attr_in6_input);
	device_create_file(&new_client->dev, &dev_attr_in6_min);
	device_create_file(&new_client->dev, &dev_attr_in6_max);
	device_create_file(&new_client->dev, &dev_attr_temp1_input);
	device_create_file(&new_client->dev, &dev_attr_temp1_max);
	device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
	device_create_file(&new_client->dev, &dev_attr_fan1_input);
	device_create_file(&new_client->dev, &dev_attr_fan1_min);
	device_create_file(&new_client->dev, &dev_attr_fan1_div);
	device_create_file(&new_client->dev, &dev_attr_fan2_input);
	device_create_file(&new_client->dev, &dev_attr_fan2_min);
	device_create_file(&new_client->dev, &dev_attr_fan2_div);
	device_create_file(&new_client->dev, &dev_attr_fan3_input);
	device_create_file(&new_client->dev, &dev_attr_fan3_min);
	device_create_file(&new_client->dev, &dev_attr_fan3_div);
	device_create_file(&new_client->dev, &dev_attr_alarms);
	device_create_file(&new_client->dev, &dev_attr_cpu0_vid);

	return 0;

ERROR3:
	i2c_detach_client(new_client);
ERROR2:
	kfree(data);
ERROR1:
	if (is_isa)
		release_region(address, LM78_EXTENT);
ERROR0:
	return err;
}

static int lm78_detach_client(struct i2c_client *client)
{
	struct lm78_data *data = i2c_get_clientdata(client);
	int err;

	hwmon_device_unregister(data->class_dev);

	if ((err = i2c_detach_client(client)))
		return err;

	if(i2c_is_isa_client(client))
		release_region(client->addr, LM78_EXTENT);

	kfree(data);

	return 0;
}

/* The SMBus locks itself, but ISA access must be locked explicitly! 
   We don't want to lock the whole ISA bus, so we lock each client
   separately.
   We ignore the LM78 BUSY flag at this moment - it could lead to deadlocks,
   would slow down the LM78 access and should not be necessary.  */
static int lm78_read_value(struct i2c_client *client, u8 reg)
{
	int res;
	if (i2c_is_isa_client(client)) {
		struct lm78_data *data = i2c_get_clientdata(client);
		down(&data->lock);
		outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
		res = inb_p(client->addr + LM78_DATA_REG_OFFSET);
		up(&data->lock);
		return res;
	} else
		return i2c_smbus_read_byte_data(client, reg);
}

/* The SMBus locks itself, but ISA access muse be locked explicitly! 
   We don't want to lock the whole ISA bus, so we lock each client
   separately.
   We ignore the LM78 BUSY flag at this moment - it could lead to deadlocks,
   would slow down the LM78 access and should not be necessary. 
   There are some ugly typecasts here, but the good new is - they should
   nowhere else be necessary! */
static int lm78_write_value(struct i2c_client *client, u8 reg, u8 value)
{
	if (i2c_is_isa_client(client)) {
		struct lm78_data *data = i2c_get_clientdata(client);
		down(&data->lock);
		outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
		outb_p(value, client->addr + LM78_DATA_REG_OFFSET);
		up(&data->lock);
		return 0;
	} else
		return i2c_smbus_write_byte_data(client, reg, value);
}

/* Called when we have found a new LM78. It should set limits, etc. */
static void lm78_init_client(struct i2c_client *client)
{
	u8 config = lm78_read_value(client, LM78_REG_CONFIG);

	/* Start monitoring */
	if (!(config & 0x01))
		lm78_write_value(client, LM78_REG_CONFIG,
				 (config & 0xf7) | 0x01);
}

static struct lm78_data *lm78_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm78_data *data = i2c_get_clientdata(client);
	int i;

	down(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	    || !data->valid) {

		dev_dbg(&client->dev, "Starting lm78 update\n");

		for (i = 0; i <= 6; i++) {
			data->in[i] =
			    lm78_read_value(client, LM78_REG_IN(i));
			data->in_min[i] =
			    lm78_read_value(client, LM78_REG_IN_MIN(i));
			data->in_max[i] =
			    lm78_read_value(client, LM78_REG_IN_MAX(i));
		}
		for (i = 0; i < 3; i++) {
			data->fan[i] =
			    lm78_read_value(client, LM78_REG_FAN(i));
			data->fan_min[i] =
			    lm78_read_value(client, LM78_REG_FAN_MIN(i));
		}
		data->temp = lm78_read_value(client, LM78_REG_TEMP);
		data->temp_over =
		    lm78_read_value(client, LM78_REG_TEMP_OVER);
		data->temp_hyst =
		    lm78_read_value(client, LM78_REG_TEMP_HYST);
		i = lm78_read_value(client, LM78_REG_VID_FANDIV);
		data->vid = i & 0x0f;
		if (data->type == lm79)
			data->vid |=
			    (lm78_read_value(client, LM78_REG_CHIPID) &
			     0x01) << 4;
		else
			data->vid |= 0x10;
		data->fan_div[0] = (i >> 4) & 0x03;
		data->fan_div[1] = i >> 6;
		data->alarms = lm78_read_value(client, LM78_REG_ALARM1) +
		    (lm78_read_value(client, LM78_REG_ALARM2) << 8);
		data->last_updated = jiffies;
		data->valid = 1;

		data->fan_div[2] = 1;
	}

	up(&data->update_lock);

	return data;
}

static int __init sm_lm78_init(void)
{
	int res;

	res = i2c_add_driver(&lm78_driver);
	if (res)
		return res;

	res = i2c_isa_add_driver(&lm78_isa_driver);
	if (res) {
		i2c_del_driver(&lm78_driver);
		return res;
	}

	return 0;
}

static void __exit sm_lm78_exit(void)
{
	i2c_isa_del_driver(&lm78_isa_driver);
	i2c_del_driver(&lm78_driver);
}



MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
MODULE_DESCRIPTION("LM78/LM79 driver");
MODULE_LICENSE("GPL");

module_init(sm_lm78_init);
module_exit(sm_lm78_exit);