aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/smsc47m1.c
blob: b3051ad7b926efac1fa7bce7bc0929372b2d8e14 (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
/*
    smsc47m1.c - Part of lm_sensors, Linux kernel modules
                 for hardware monitoring

    Supports the SMSC LPC47B27x, LPC47M10x, LPC47M13x, LPC47M14x,
    LPC47M15x, LPC47M192 and LPC47M997 Super-I/O chips.

    Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
    Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
    Ported to Linux 2.6 by Gabriele Gorla <gorlik@yahoo.com>
                        and Jean Delvare

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

/* Address is autodetected, there is no default value */
static unsigned short address;

/* Super-I/0 registers and commands */

#define	REG	0x2e	/* The register to read/write */
#define	VAL	0x2f	/* The value to read/write */

static inline void
superio_outb(int reg, int val)
{
	outb(reg, REG);
	outb(val, VAL);
}

static inline int
superio_inb(int reg)
{
	outb(reg, REG);
	return inb(VAL);
}

/* logical device for fans is 0x0A */
#define superio_select() superio_outb(0x07, 0x0A)

static inline void
superio_enter(void)
{
	outb(0x55, REG);
}

static inline void
superio_exit(void)
{
	outb(0xAA, REG);
}

#define SUPERIO_REG_ACT		0x30
#define SUPERIO_REG_BASE	0x60
#define SUPERIO_REG_DEVID	0x20

/* Logical device registers */

#define SMSC_EXTENT		0x80

/* nr is 0 or 1 in the macros below */
#define SMSC47M1_REG_ALARM		0x04
#define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
#define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
#define SMSC47M1_REG_PWM(nr)		(0x56 + (nr))
#define SMSC47M1_REG_FANDIV		0x58
#define SMSC47M1_REG_FAN(nr)		(0x59 + (nr))
#define SMSC47M1_REG_FAN_PRELOAD(nr)	(0x5B + (nr))

#define MIN_FROM_REG(reg,div)		((reg)>=192 ? 0 : \
					 983040/((192-(reg))*(div)))
#define FAN_FROM_REG(reg,div,preload)	((reg)<=(preload) || (reg)==255 ? 0 : \
					 983040/(((reg)-(preload))*(div)))
#define DIV_FROM_REG(reg)		(1 << (reg))
#define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
#define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
#define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)

struct smsc47m1_data {
	struct i2c_client client;
	struct class_device *class_dev;
	struct semaphore lock;

	struct semaphore update_lock;
	unsigned long last_updated;	/* In jiffies */

	u8 fan[2];		/* Register value */
	u8 fan_preload[2];	/* Register value */
	u8 fan_div[2];		/* Register encoding, shifted right */
	u8 alarms;		/* Register encoding */
	u8 pwm[2];		/* Register value (bit 7 is enable) */
};


static int smsc47m1_detect(struct i2c_adapter *adapter);
static int smsc47m1_detach_client(struct i2c_client *client);

static int smsc47m1_read_value(struct i2c_client *client, u8 reg);
static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value);

static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
		int init);


static struct i2c_driver smsc47m1_driver = {
	.driver = {
		.owner	= THIS_MODULE,
		.name	= "smsc47m1",
	},
	.attach_adapter	= smsc47m1_detect,
	.detach_client	= smsc47m1_detach_client,
};

/* nr is 0 or 1 in the callback functions below */

static ssize_t get_fan(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	/* This chip (stupidly) stops monitoring fan speed if PWM is
	   enabled and duty cycle is 0%. This is fine if the monitoring
	   and control concern the same fan, but troublesome if they are
	   not (which could as well happen). */
	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
		  FAN_FROM_REG(data->fan[nr],
			       DIV_FROM_REG(data->fan_div[nr]),
			       data->fan_preload[nr]);
	return sprintf(buf, "%d\n", rpm);
}

static ssize_t get_fan_min(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	int rpm = MIN_FROM_REG(data->fan_preload[nr],
			       DIV_FROM_REG(data->fan_div[nr]));
	return sprintf(buf, "%d\n", rpm);
}

static ssize_t get_fan_div(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
}

static ssize_t get_pwm(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[nr]));
}

static ssize_t get_pwm_en(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[nr]));
}

static ssize_t get_alarms(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", data->alarms);
}

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 smsc47m1_data *data = i2c_get_clientdata(client);
	long rpmdiv, val = simple_strtol(buf, NULL, 10);

	down(&data->update_lock);
	rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);

	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {
		up(&data->update_lock);
		return -EINVAL;
	}

	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
			     data->fan_preload[nr]);
	up(&data->update_lock);

	return count;
}

/* Note: we save and restore the fan minimum here, because its value is
   determined in part by the fan clock divider.  This follows the principle
   of least suprise; the user doesn't expect the fan minimum to change just
   because the divider 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 smsc47m1_data *data = i2c_get_clientdata(client);

	long new_div = simple_strtol(buf, NULL, 10), tmp;
	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);

	if (new_div == old_div) /* No change */
		return count;

	down(&data->update_lock);
	switch (new_div) {
	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:
		up(&data->update_lock);
		return -EINVAL;
	}

	tmp = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV) & 0x0F;
	tmp |= (data->fan_div[0] << 4) | (data->fan_div[1] << 6);
	smsc47m1_write_value(client, SMSC47M1_REG_FANDIV, tmp);

	/* Preserve fan min */
	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
		     + new_div / 2) / new_div;
	data->fan_preload[nr] = SENSORS_LIMIT(tmp, 0, 191);
	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
			     data->fan_preload[nr]);
	up(&data->update_lock);

	return count;
}

static ssize_t set_pwm(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long val = simple_strtol(buf, NULL, 10);

	if (val < 0 || val > 255)
		return -EINVAL;

	down(&data->update_lock);
	data->pwm[nr] &= 0x81; /* Preserve additional bits */
	data->pwm[nr] |= PWM_TO_REG(val);
	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
			     data->pwm[nr]);
	up(&data->update_lock);

	return count;
}

static ssize_t set_pwm_en(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long val = simple_strtol(buf, NULL, 10);
	
	if (val != 0 && val != 1)
		return -EINVAL;

	down(&data->update_lock);
	data->pwm[nr] &= 0xFE; /* preserve the other bits */
	data->pwm[nr] |= !val;
	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
			     data->pwm[nr]);
	up(&data->update_lock);

	return count;
}

#define fan_present(offset)						\
static ssize_t get_fan##offset (struct device *dev, struct device_attribute *attr, char *buf)		\
{									\
	return get_fan(dev, buf, offset - 1);				\
}									\
static ssize_t get_fan##offset##_min (struct device *dev, struct device_attribute *attr, char *buf)	\
{									\
	return get_fan_min(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 ssize_t get_fan##offset##_div (struct device *dev, struct device_attribute *attr, char *buf)	\
{									\
	return get_fan_div(dev, buf, offset - 1);			\
}									\
static ssize_t set_fan##offset##_div (struct device *dev, struct device_attribute *attr,		\
		const char *buf, size_t count)				\
{									\
	return set_fan_div(dev, buf, count, offset - 1);		\
}									\
static ssize_t get_pwm##offset (struct device *dev, struct device_attribute *attr, char *buf)		\
{									\
	return get_pwm(dev, buf, offset - 1);				\
}									\
static ssize_t set_pwm##offset (struct device *dev, struct device_attribute *attr,			\
		const char *buf, size_t count)				\
{									\
	return set_pwm(dev, buf, count, offset - 1);			\
}									\
static ssize_t get_pwm##offset##_en (struct device *dev, struct device_attribute *attr, char *buf)	\
{									\
	return get_pwm_en(dev, buf, offset - 1);			\
}									\
static ssize_t set_pwm##offset##_en (struct device *dev, struct device_attribute *attr,		\
		const char *buf, size_t count)				\
{									\
	return set_pwm_en(dev, buf, count, offset - 1);			\
}									\
static DEVICE_ATTR(fan##offset##_input, S_IRUGO, get_fan##offset,	\
		NULL);							\
static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
		get_fan##offset##_min, set_fan##offset##_min);		\
static DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
		get_fan##offset##_div, set_fan##offset##_div);		\
static DEVICE_ATTR(pwm##offset, S_IRUGO | S_IWUSR,			\
		get_pwm##offset, set_pwm##offset);			\
static DEVICE_ATTR(pwm##offset##_enable, S_IRUGO | S_IWUSR,		\
		get_pwm##offset##_en, set_pwm##offset##_en);

fan_present(1);
fan_present(2);

static DEVICE_ATTR(alarms, S_IRUGO, get_alarms, NULL);

static int __init smsc47m1_find(unsigned short *addr)
{
	u8 val;

	superio_enter();
	val = superio_inb(SUPERIO_REG_DEVID);

	/*
	 * SMSC LPC47M10x/LPC47M13x (device id 0x59), LPC47M14x (device id
	 * 0x5F) and LPC47B27x (device id 0x51) have fan control.
	 * The LPC47M15x and LPC47M192 chips "with hardware monitoring block"
	 * can do much more besides (device id 0x60).
	 * The LPC47M997 is undocumented, but seems to be compatible with
	 * the LPC47M192, and has the same device id.
	 */
	if (val == 0x51)
		printk(KERN_INFO "smsc47m1: Found SMSC LPC47B27x\n");
	else if (val == 0x59)
		printk(KERN_INFO "smsc47m1: Found SMSC LPC47M10x/LPC47M13x\n");
	else if (val == 0x5F)
		printk(KERN_INFO "smsc47m1: Found SMSC LPC47M14x\n");
	else if (val == 0x60)
		printk(KERN_INFO "smsc47m1: Found SMSC "
		       "LPC47M15x/LPC47M192/LPC47M997\n");
	else {
		superio_exit();
		return -ENODEV;
	}

	superio_select();
	*addr = (superio_inb(SUPERIO_REG_BASE) << 8)
	      |  superio_inb(SUPERIO_REG_BASE + 1);
	val = superio_inb(SUPERIO_REG_ACT);
	if (*addr == 0 || (val & 0x01) == 0) {
		printk(KERN_INFO "smsc47m1: Device is disabled, will not use\n");
		superio_exit();
		return -ENODEV;
	}

	superio_exit();
	return 0;
}

static int smsc47m1_detect(struct i2c_adapter *adapter)
{
	struct i2c_client *new_client;
	struct smsc47m1_data *data;
	int err = 0;
	int fan1, fan2, pwm1, pwm2;

	if (!request_region(address, SMSC_EXTENT, smsc47m1_driver.driver.name)) {
		dev_err(&adapter->dev, "Region 0x%x already in use!\n", address);
		return -EBUSY;
	}

	if (!(data = kzalloc(sizeof(struct smsc47m1_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto error_release;
	}

	new_client = &data->client;
	i2c_set_clientdata(new_client, data);
	new_client->addr = address;
	init_MUTEX(&data->lock);
	new_client->adapter = adapter;
	new_client->driver = &smsc47m1_driver;
	new_client->flags = 0;

	strlcpy(new_client->name, "smsc47m1", I2C_NAME_SIZE);
	init_MUTEX(&data->update_lock);

	/* If no function is properly configured, there's no point in
	   actually registering the chip. */
	fan1 = (smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(0)) & 0x05)
	       == 0x05;
	fan2 = (smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(1)) & 0x05)
	       == 0x05;
	pwm1 = (smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(0)) & 0x05)
	       == 0x04;
	pwm2 = (smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(1)) & 0x05)
	       == 0x04;
	if (!(fan1 || fan2 || pwm1 || pwm2)) {
		dev_warn(&new_client->dev, "Device is not configured, will not use\n");
		err = -ENODEV;
		goto error_free;
	}

	if ((err = i2c_attach_client(new_client)))
		goto error_free;

	/* Some values (fan min, clock dividers, pwm registers) may be
	   needed before any update is triggered, so we better read them
	   at least once here. We don't usually do it that way, but in
	   this particular case, manually reading 5 registers out of 8
	   doesn't make much sense and we're better using the existing
	   function. */
	smsc47m1_update_device(&new_client->dev, 1);

	/* 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 error_detach;
	}

	if (fan1) {
		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);
	} else
		dev_dbg(&new_client->dev, "Fan 1 not enabled by hardware, "
			"skipping\n");

	if (fan2) {
		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);
	} else
		dev_dbg(&new_client->dev, "Fan 2 not enabled by hardware, "
			"skipping\n");

	if (pwm1) {
		device_create_file(&new_client->dev, &dev_attr_pwm1);
		device_create_file(&new_client->dev, &dev_attr_pwm1_enable);
	} else
		dev_dbg(&new_client->dev, "PWM 1 not enabled by hardware, "
			"skipping\n");
	if (pwm2) {
		device_create_file(&new_client->dev, &dev_attr_pwm2);
		device_create_file(&new_client->dev, &dev_attr_pwm2_enable);
	} else
		dev_dbg(&new_client->dev, "PWM 2 not enabled by hardware, "
			"skipping\n");

	device_create_file(&new_client->dev, &dev_attr_alarms);

	return 0;

error_detach:
	i2c_detach_client(new_client);
error_free:
	kfree(data);
error_release:
	release_region(address, SMSC_EXTENT);
	return err;
}

static int smsc47m1_detach_client(struct i2c_client *client)
{
	struct smsc47m1_data *data = i2c_get_clientdata(client);
	int err;

	hwmon_device_unregister(data->class_dev);

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

	release_region(client->addr, SMSC_EXTENT);
	kfree(data);

	return 0;
}

static int smsc47m1_read_value(struct i2c_client *client, u8 reg)
{
	int res;

	down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
	res = inb_p(client->addr + reg);
	up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
	return res;
}

static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value)
{
	down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
	outb_p(value, client->addr + reg);
	up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
}

static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
		int init)
{
 	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	down(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
		int i;

		for (i = 0; i < 2; i++) {
			data->fan[i] = smsc47m1_read_value(client,
				       SMSC47M1_REG_FAN(i));
			data->fan_preload[i] = smsc47m1_read_value(client,
					       SMSC47M1_REG_FAN_PRELOAD(i));
			data->pwm[i] = smsc47m1_read_value(client,
				       SMSC47M1_REG_PWM(i));
		}

		i = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV);
		data->fan_div[0] = (i >> 4) & 0x03;
		data->fan_div[1] = i >> 6;

		data->alarms = smsc47m1_read_value(client,
			       SMSC47M1_REG_ALARM) >> 6;
		/* Clear alarms if needed */
		if (data->alarms)
			smsc47m1_write_value(client, SMSC47M1_REG_ALARM, 0xC0);

		data->last_updated = jiffies;
	}

	up(&data->update_lock);
	return data;
}

static int __init sm_smsc47m1_init(void)
{
	if (smsc47m1_find(&address)) {
		return -ENODEV;
	}

	return i2c_isa_add_driver(&smsc47m1_driver);
}

static void __exit sm_smsc47m1_exit(void)
{
	i2c_isa_del_driver(&smsc47m1_driver);
}

MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
MODULE_LICENSE("GPL");

module_init(sm_smsc47m1_init);
module_exit(sm_smsc47m1_exit);