xref: /openbmc/linux/drivers/hwmon/smsc47m1.c (revision 2c64e9cb)
1 /*
2  * smsc47m1.c - Part of lm_sensors, Linux kernel modules
3  *		for hardware monitoring
4  *
5  * Supports the SMSC LPC47B27x, LPC47M10x, LPC47M112, LPC47M13x,
6  * LPC47M14x, LPC47M15x, LPC47M192, LPC47M292 and LPC47M997
7  * Super-I/O chips.
8  *
9  * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
10  * Copyright (C) 2004-2007 Jean Delvare <jdelvare@suse.de>
11  * Ported to Linux 2.6 by Gabriele Gorla <gorlik@yahoo.com>
12  *			and Jean Delvare
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program; if not, write to the Free Software
26  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27  */
28 
29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30 
31 #include <linux/module.h>
32 #include <linux/slab.h>
33 #include <linux/ioport.h>
34 #include <linux/jiffies.h>
35 #include <linux/platform_device.h>
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 #include <linux/err.h>
39 #include <linux/init.h>
40 #include <linux/mutex.h>
41 #include <linux/sysfs.h>
42 #include <linux/acpi.h>
43 #include <linux/io.h>
44 
45 static unsigned short force_id;
46 module_param(force_id, ushort, 0);
47 MODULE_PARM_DESC(force_id, "Override the detected device ID");
48 
49 static struct platform_device *pdev;
50 
51 #define DRVNAME "smsc47m1"
52 enum chips { smsc47m1, smsc47m2 };
53 
54 /* Super-I/0 registers and commands */
55 
56 #define REG	0x2e	/* The register to read/write */
57 #define VAL	0x2f	/* The value to read/write */
58 
59 static inline void
60 superio_outb(int reg, int val)
61 {
62 	outb(reg, REG);
63 	outb(val, VAL);
64 }
65 
66 static inline int
67 superio_inb(int reg)
68 {
69 	outb(reg, REG);
70 	return inb(VAL);
71 }
72 
73 /* logical device for fans is 0x0A */
74 #define superio_select() superio_outb(0x07, 0x0A)
75 
76 static inline int
77 superio_enter(void)
78 {
79 	if (!request_muxed_region(REG, 2, DRVNAME))
80 		return -EBUSY;
81 
82 	outb(0x55, REG);
83 	return 0;
84 }
85 
86 static inline void
87 superio_exit(void)
88 {
89 	outb(0xAA, REG);
90 	release_region(REG, 2);
91 }
92 
93 #define SUPERIO_REG_ACT		0x30
94 #define SUPERIO_REG_BASE	0x60
95 #define SUPERIO_REG_DEVID	0x20
96 #define SUPERIO_REG_DEVREV	0x21
97 
98 /* Logical device registers */
99 
100 #define SMSC_EXTENT		0x80
101 
102 /* nr is 0 or 1 in the macros below */
103 #define SMSC47M1_REG_ALARM		0x04
104 #define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
105 #define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
106 #define SMSC47M1_REG_FANDIV		0x58
107 
108 static const u8 SMSC47M1_REG_FAN[3]		= { 0x59, 0x5a, 0x6b };
109 static const u8 SMSC47M1_REG_FAN_PRELOAD[3]	= { 0x5b, 0x5c, 0x6c };
110 static const u8 SMSC47M1_REG_PWM[3]		= { 0x56, 0x57, 0x69 };
111 
112 #define SMSC47M2_REG_ALARM6		0x09
113 #define SMSC47M2_REG_TPIN1		0x38
114 #define SMSC47M2_REG_TPIN2		0x37
115 #define SMSC47M2_REG_TPIN3		0x2d
116 #define SMSC47M2_REG_PPIN3		0x2c
117 #define SMSC47M2_REG_FANDIV3		0x6a
118 
119 #define MIN_FROM_REG(reg, div)		((reg) >= 192 ? 0 : \
120 					 983040 / ((192 - (reg)) * (div)))
121 #define FAN_FROM_REG(reg, div, preload)	((reg) <= (preload) || (reg) == 255 ? \
122 					 0 : \
123 					 983040 / (((reg) - (preload)) * (div)))
124 #define DIV_FROM_REG(reg)		(1 << (reg))
125 #define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
126 #define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
127 #define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)
128 
129 struct smsc47m1_data {
130 	unsigned short addr;
131 	const char *name;
132 	enum chips type;
133 	struct device *hwmon_dev;
134 
135 	struct mutex update_lock;
136 	unsigned long last_updated;	/* In jiffies */
137 
138 	u8 fan[3];		/* Register value */
139 	u8 fan_preload[3];	/* Register value */
140 	u8 fan_div[3];		/* Register encoding, shifted right */
141 	u8 alarms;		/* Register encoding */
142 	u8 pwm[3];		/* Register value (bit 0 is disable) */
143 };
144 
145 struct smsc47m1_sio_data {
146 	enum chips type;
147 	u8 activate;		/* Remember initial device state */
148 };
149 
150 static inline int smsc47m1_read_value(struct smsc47m1_data *data, u8 reg)
151 {
152 	return inb_p(data->addr + reg);
153 }
154 
155 static inline void smsc47m1_write_value(struct smsc47m1_data *data, u8 reg,
156 		u8 value)
157 {
158 	outb_p(value, data->addr + reg);
159 }
160 
161 static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
162 		int init)
163 {
164 	struct smsc47m1_data *data = dev_get_drvdata(dev);
165 
166 	mutex_lock(&data->update_lock);
167 
168 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
169 		int i, fan_nr;
170 		fan_nr = data->type == smsc47m2 ? 3 : 2;
171 
172 		for (i = 0; i < fan_nr; i++) {
173 			data->fan[i] = smsc47m1_read_value(data,
174 				       SMSC47M1_REG_FAN[i]);
175 			data->fan_preload[i] = smsc47m1_read_value(data,
176 					       SMSC47M1_REG_FAN_PRELOAD[i]);
177 			data->pwm[i] = smsc47m1_read_value(data,
178 				       SMSC47M1_REG_PWM[i]);
179 		}
180 
181 		i = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV);
182 		data->fan_div[0] = (i >> 4) & 0x03;
183 		data->fan_div[1] = i >> 6;
184 
185 		data->alarms = smsc47m1_read_value(data,
186 			       SMSC47M1_REG_ALARM) >> 6;
187 		/* Clear alarms if needed */
188 		if (data->alarms)
189 			smsc47m1_write_value(data, SMSC47M1_REG_ALARM, 0xC0);
190 
191 		if (fan_nr >= 3) {
192 			data->fan_div[2] = (smsc47m1_read_value(data,
193 					    SMSC47M2_REG_FANDIV3) >> 4) & 0x03;
194 			data->alarms |= (smsc47m1_read_value(data,
195 					 SMSC47M2_REG_ALARM6) & 0x40) >> 4;
196 			/* Clear alarm if needed */
197 			if (data->alarms & 0x04)
198 				smsc47m1_write_value(data,
199 						     SMSC47M2_REG_ALARM6,
200 						     0x40);
201 		}
202 
203 		data->last_updated = jiffies;
204 	}
205 
206 	mutex_unlock(&data->update_lock);
207 	return data;
208 }
209 
210 static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
211 			char *buf)
212 {
213 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
214 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
215 	int nr = attr->index;
216 	/*
217 	 * This chip (stupidly) stops monitoring fan speed if PWM is
218 	 * enabled and duty cycle is 0%. This is fine if the monitoring
219 	 * and control concern the same fan, but troublesome if they are
220 	 * not (which could as well happen).
221 	 */
222 	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
223 		  FAN_FROM_REG(data->fan[nr],
224 			       DIV_FROM_REG(data->fan_div[nr]),
225 			       data->fan_preload[nr]);
226 	return sprintf(buf, "%d\n", rpm);
227 }
228 
229 static ssize_t fan_min_show(struct device *dev,
230 			    struct device_attribute *devattr, char *buf)
231 {
232 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
233 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
234 	int nr = attr->index;
235 	int rpm = MIN_FROM_REG(data->fan_preload[nr],
236 			       DIV_FROM_REG(data->fan_div[nr]));
237 	return sprintf(buf, "%d\n", rpm);
238 }
239 
240 static ssize_t fan_div_show(struct device *dev,
241 			    struct device_attribute *devattr, char *buf)
242 {
243 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
244 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
245 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
246 }
247 
248 static ssize_t fan_alarm_show(struct device *dev,
249 			      struct device_attribute *devattr, char *buf)
250 {
251 	int bitnr = to_sensor_dev_attr(devattr)->index;
252 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
253 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
254 }
255 
256 static ssize_t pwm_show(struct device *dev, struct device_attribute *devattr,
257 			char *buf)
258 {
259 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
260 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
261 	return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[attr->index]));
262 }
263 
264 static ssize_t pwm_en_show(struct device *dev,
265 			   struct device_attribute *devattr, char *buf)
266 {
267 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
268 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
269 	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[attr->index]));
270 }
271 
272 static ssize_t alarms_show(struct device *dev,
273 			   struct device_attribute *devattr, char *buf)
274 {
275 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
276 	return sprintf(buf, "%d\n", data->alarms);
277 }
278 
279 static ssize_t fan_min_store(struct device *dev,
280 			     struct device_attribute *devattr,
281 			     const char *buf, size_t count)
282 {
283 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
284 	struct smsc47m1_data *data = dev_get_drvdata(dev);
285 	int nr = attr->index;
286 	long rpmdiv;
287 	long val;
288 	int err;
289 
290 	err = kstrtol(buf, 10, &val);
291 	if (err)
292 		return err;
293 
294 	mutex_lock(&data->update_lock);
295 	rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);
296 
297 	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {
298 		mutex_unlock(&data->update_lock);
299 		return -EINVAL;
300 	}
301 
302 	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
303 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
304 			     data->fan_preload[nr]);
305 	mutex_unlock(&data->update_lock);
306 
307 	return count;
308 }
309 
310 /*
311  * Note: we save and restore the fan minimum here, because its value is
312  * determined in part by the fan clock divider.  This follows the principle
313  * of least surprise; the user doesn't expect the fan minimum to change just
314  * because the divider changed.
315  */
316 static ssize_t fan_div_store(struct device *dev,
317 			     struct device_attribute *devattr,
318 			     const char *buf, size_t count)
319 {
320 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
321 	struct smsc47m1_data *data = dev_get_drvdata(dev);
322 	int nr = attr->index;
323 	long new_div;
324 	int err;
325 	long tmp;
326 	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);
327 
328 	err = kstrtol(buf, 10, &new_div);
329 	if (err)
330 		return err;
331 
332 	if (new_div == old_div) /* No change */
333 		return count;
334 
335 	mutex_lock(&data->update_lock);
336 	switch (new_div) {
337 	case 1:
338 		data->fan_div[nr] = 0;
339 		break;
340 	case 2:
341 		data->fan_div[nr] = 1;
342 		break;
343 	case 4:
344 		data->fan_div[nr] = 2;
345 		break;
346 	case 8:
347 		data->fan_div[nr] = 3;
348 		break;
349 	default:
350 		mutex_unlock(&data->update_lock);
351 		return -EINVAL;
352 	}
353 
354 	switch (nr) {
355 	case 0:
356 	case 1:
357 		tmp = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV)
358 		      & ~(0x03 << (4 + 2 * nr));
359 		tmp |= data->fan_div[nr] << (4 + 2 * nr);
360 		smsc47m1_write_value(data, SMSC47M1_REG_FANDIV, tmp);
361 		break;
362 	case 2:
363 		tmp = smsc47m1_read_value(data, SMSC47M2_REG_FANDIV3) & 0xCF;
364 		tmp |= data->fan_div[2] << 4;
365 		smsc47m1_write_value(data, SMSC47M2_REG_FANDIV3, tmp);
366 		break;
367 	}
368 
369 	/* Preserve fan min */
370 	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
371 		     + new_div / 2) / new_div;
372 	data->fan_preload[nr] = clamp_val(tmp, 0, 191);
373 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
374 			     data->fan_preload[nr]);
375 	mutex_unlock(&data->update_lock);
376 
377 	return count;
378 }
379 
380 static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
381 			 const char *buf, size_t count)
382 {
383 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
384 	struct smsc47m1_data *data = dev_get_drvdata(dev);
385 	int nr = attr->index;
386 	long val;
387 	int err;
388 
389 	err = kstrtol(buf, 10, &val);
390 	if (err)
391 		return err;
392 
393 	if (val < 0 || val > 255)
394 		return -EINVAL;
395 
396 	mutex_lock(&data->update_lock);
397 	data->pwm[nr] &= 0x81; /* Preserve additional bits */
398 	data->pwm[nr] |= PWM_TO_REG(val);
399 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
400 			     data->pwm[nr]);
401 	mutex_unlock(&data->update_lock);
402 
403 	return count;
404 }
405 
406 static ssize_t pwm_en_store(struct device *dev,
407 			    struct device_attribute *devattr, const char *buf,
408 			    size_t count)
409 {
410 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
411 	struct smsc47m1_data *data = dev_get_drvdata(dev);
412 	int nr = attr->index;
413 	unsigned long val;
414 	int err;
415 
416 	err = kstrtoul(buf, 10, &val);
417 	if (err)
418 		return err;
419 
420 	if (val > 1)
421 		return -EINVAL;
422 
423 	mutex_lock(&data->update_lock);
424 	data->pwm[nr] &= 0xFE; /* preserve the other bits */
425 	data->pwm[nr] |= !val;
426 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
427 			     data->pwm[nr]);
428 	mutex_unlock(&data->update_lock);
429 
430 	return count;
431 }
432 
433 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
434 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
435 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
436 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, fan_alarm, 0);
437 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0);
438 static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm_en, 0);
439 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
440 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
441 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
442 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, fan_alarm, 1);
443 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1);
444 static SENSOR_DEVICE_ATTR_RW(pwm2_enable, pwm_en, 1);
445 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
446 static SENSOR_DEVICE_ATTR_RW(fan3_min, fan_min, 2);
447 static SENSOR_DEVICE_ATTR_RW(fan3_div, fan_div, 2);
448 static SENSOR_DEVICE_ATTR_RO(fan3_alarm, fan_alarm, 2);
449 static SENSOR_DEVICE_ATTR_RW(pwm3, pwm, 2);
450 static SENSOR_DEVICE_ATTR_RW(pwm3_enable, pwm_en, 2);
451 
452 static DEVICE_ATTR_RO(alarms);
453 
454 static ssize_t name_show(struct device *dev, struct device_attribute
455 			 *devattr, char *buf)
456 {
457 	struct smsc47m1_data *data = dev_get_drvdata(dev);
458 
459 	return sprintf(buf, "%s\n", data->name);
460 }
461 static DEVICE_ATTR_RO(name);
462 
463 static struct attribute *smsc47m1_attributes_fan1[] = {
464 	&sensor_dev_attr_fan1_input.dev_attr.attr,
465 	&sensor_dev_attr_fan1_min.dev_attr.attr,
466 	&sensor_dev_attr_fan1_div.dev_attr.attr,
467 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
468 	NULL
469 };
470 
471 static const struct attribute_group smsc47m1_group_fan1 = {
472 	.attrs = smsc47m1_attributes_fan1,
473 };
474 
475 static struct attribute *smsc47m1_attributes_fan2[] = {
476 	&sensor_dev_attr_fan2_input.dev_attr.attr,
477 	&sensor_dev_attr_fan2_min.dev_attr.attr,
478 	&sensor_dev_attr_fan2_div.dev_attr.attr,
479 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
480 	NULL
481 };
482 
483 static const struct attribute_group smsc47m1_group_fan2 = {
484 	.attrs = smsc47m1_attributes_fan2,
485 };
486 
487 static struct attribute *smsc47m1_attributes_fan3[] = {
488 	&sensor_dev_attr_fan3_input.dev_attr.attr,
489 	&sensor_dev_attr_fan3_min.dev_attr.attr,
490 	&sensor_dev_attr_fan3_div.dev_attr.attr,
491 	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
492 	NULL
493 };
494 
495 static const struct attribute_group smsc47m1_group_fan3 = {
496 	.attrs = smsc47m1_attributes_fan3,
497 };
498 
499 static struct attribute *smsc47m1_attributes_pwm1[] = {
500 	&sensor_dev_attr_pwm1.dev_attr.attr,
501 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
502 	NULL
503 };
504 
505 static const struct attribute_group smsc47m1_group_pwm1 = {
506 	.attrs = smsc47m1_attributes_pwm1,
507 };
508 
509 static struct attribute *smsc47m1_attributes_pwm2[] = {
510 	&sensor_dev_attr_pwm2.dev_attr.attr,
511 	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
512 	NULL
513 };
514 
515 static const struct attribute_group smsc47m1_group_pwm2 = {
516 	.attrs = smsc47m1_attributes_pwm2,
517 };
518 
519 static struct attribute *smsc47m1_attributes_pwm3[] = {
520 	&sensor_dev_attr_pwm3.dev_attr.attr,
521 	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
522 	NULL
523 };
524 
525 static const struct attribute_group smsc47m1_group_pwm3 = {
526 	.attrs = smsc47m1_attributes_pwm3,
527 };
528 
529 static struct attribute *smsc47m1_attributes[] = {
530 	&dev_attr_alarms.attr,
531 	&dev_attr_name.attr,
532 	NULL
533 };
534 
535 static const struct attribute_group smsc47m1_group = {
536 	.attrs = smsc47m1_attributes,
537 };
538 
539 static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
540 {
541 	u8 val;
542 	unsigned short addr;
543 	int err;
544 
545 	err = superio_enter();
546 	if (err)
547 		return err;
548 
549 	val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
550 
551 	/*
552 	 * SMSC LPC47M10x/LPC47M112/LPC47M13x (device id 0x59), LPC47M14x
553 	 * (device id 0x5F) and LPC47B27x (device id 0x51) have fan control.
554 	 * The LPC47M15x and LPC47M192 chips "with hardware monitoring block"
555 	 * can do much more besides (device id 0x60).
556 	 * The LPC47M997 is undocumented, but seems to be compatible with
557 	 * the LPC47M192, and has the same device id.
558 	 * The LPC47M292 (device id 0x6B) is somewhat compatible, but it
559 	 * supports a 3rd fan, and the pin configuration registers are
560 	 * unfortunately different.
561 	 * The LPC47M233 has the same device id (0x6B) but is not compatible.
562 	 * We check the high bit of the device revision register to
563 	 * differentiate them.
564 	 */
565 	switch (val) {
566 	case 0x51:
567 		pr_info("Found SMSC LPC47B27x\n");
568 		sio_data->type = smsc47m1;
569 		break;
570 	case 0x59:
571 		pr_info("Found SMSC LPC47M10x/LPC47M112/LPC47M13x\n");
572 		sio_data->type = smsc47m1;
573 		break;
574 	case 0x5F:
575 		pr_info("Found SMSC LPC47M14x\n");
576 		sio_data->type = smsc47m1;
577 		break;
578 	case 0x60:
579 		pr_info("Found SMSC LPC47M15x/LPC47M192/LPC47M997\n");
580 		sio_data->type = smsc47m1;
581 		break;
582 	case 0x6B:
583 		if (superio_inb(SUPERIO_REG_DEVREV) & 0x80) {
584 			pr_debug("Found SMSC LPC47M233, unsupported\n");
585 			superio_exit();
586 			return -ENODEV;
587 		}
588 
589 		pr_info("Found SMSC LPC47M292\n");
590 		sio_data->type = smsc47m2;
591 		break;
592 	default:
593 		superio_exit();
594 		return -ENODEV;
595 	}
596 
597 	superio_select();
598 	addr = (superio_inb(SUPERIO_REG_BASE) << 8)
599 	      |  superio_inb(SUPERIO_REG_BASE + 1);
600 	if (addr == 0) {
601 		pr_info("Device address not set, will not use\n");
602 		superio_exit();
603 		return -ENODEV;
604 	}
605 
606 	/*
607 	 * Enable only if address is set (needed at least on the
608 	 * Compaq Presario S4000NX)
609 	 */
610 	sio_data->activate = superio_inb(SUPERIO_REG_ACT);
611 	if ((sio_data->activate & 0x01) == 0) {
612 		pr_info("Enabling device\n");
613 		superio_outb(SUPERIO_REG_ACT, sio_data->activate | 0x01);
614 	}
615 
616 	superio_exit();
617 	return addr;
618 }
619 
620 /* Restore device to its initial state */
621 static void smsc47m1_restore(const struct smsc47m1_sio_data *sio_data)
622 {
623 	if ((sio_data->activate & 0x01) == 0) {
624 		if (!superio_enter()) {
625 			superio_select();
626 			pr_info("Disabling device\n");
627 			superio_outb(SUPERIO_REG_ACT, sio_data->activate);
628 			superio_exit();
629 		} else {
630 			pr_warn("Failed to disable device\n");
631 		}
632 	}
633 }
634 
635 #define CHECK		1
636 #define REQUEST		2
637 
638 /*
639  * This function can be used to:
640  *  - test for resource conflicts with ACPI
641  *  - request the resources
642  * We only allocate the I/O ports we really need, to minimize the risk of
643  * conflicts with ACPI or with other drivers.
644  */
645 static int __init smsc47m1_handle_resources(unsigned short address,
646 					    enum chips type, int action,
647 					    struct device *dev)
648 {
649 	static const u8 ports_m1[] = {
650 		/* register, region length */
651 		0x04, 1,
652 		0x33, 4,
653 		0x56, 7,
654 	};
655 
656 	static const u8 ports_m2[] = {
657 		/* register, region length */
658 		0x04, 1,
659 		0x09, 1,
660 		0x2c, 2,
661 		0x35, 4,
662 		0x56, 7,
663 		0x69, 4,
664 	};
665 
666 	int i, ports_size, err;
667 	const u8 *ports;
668 
669 	switch (type) {
670 	case smsc47m1:
671 	default:
672 		ports = ports_m1;
673 		ports_size = ARRAY_SIZE(ports_m1);
674 		break;
675 	case smsc47m2:
676 		ports = ports_m2;
677 		ports_size = ARRAY_SIZE(ports_m2);
678 		break;
679 	}
680 
681 	for (i = 0; i + 1 < ports_size; i += 2) {
682 		unsigned short start = address + ports[i];
683 		unsigned short len = ports[i + 1];
684 
685 		switch (action) {
686 		case CHECK:
687 			/* Only check for conflicts */
688 			err = acpi_check_region(start, len, DRVNAME);
689 			if (err)
690 				return err;
691 			break;
692 		case REQUEST:
693 			/* Request the resources */
694 			if (!devm_request_region(dev, start, len, DRVNAME)) {
695 				dev_err(dev,
696 					"Region 0x%hx-0x%hx already in use!\n",
697 					start, start + len);
698 				return -EBUSY;
699 			}
700 			break;
701 		}
702 	}
703 
704 	return 0;
705 }
706 
707 static void smsc47m1_remove_files(struct device *dev)
708 {
709 	sysfs_remove_group(&dev->kobj, &smsc47m1_group);
710 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan1);
711 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan2);
712 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan3);
713 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm1);
714 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm2);
715 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm3);
716 }
717 
718 static int __init smsc47m1_probe(struct platform_device *pdev)
719 {
720 	struct device *dev = &pdev->dev;
721 	struct smsc47m1_sio_data *sio_data = dev_get_platdata(dev);
722 	struct smsc47m1_data *data;
723 	struct resource *res;
724 	int err;
725 	int fan1, fan2, fan3, pwm1, pwm2, pwm3;
726 
727 	static const char * const names[] = {
728 		"smsc47m1",
729 		"smsc47m2",
730 	};
731 
732 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
733 	err = smsc47m1_handle_resources(res->start, sio_data->type,
734 					REQUEST, dev);
735 	if (err < 0)
736 		return err;
737 
738 	data = devm_kzalloc(dev, sizeof(struct smsc47m1_data), GFP_KERNEL);
739 	if (!data)
740 		return -ENOMEM;
741 
742 	data->addr = res->start;
743 	data->type = sio_data->type;
744 	data->name = names[sio_data->type];
745 	mutex_init(&data->update_lock);
746 	platform_set_drvdata(pdev, data);
747 
748 	/*
749 	 * If no function is properly configured, there's no point in
750 	 * actually registering the chip.
751 	 */
752 	pwm1 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(0)) & 0x05)
753 	       == 0x04;
754 	pwm2 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(1)) & 0x05)
755 	       == 0x04;
756 	if (data->type == smsc47m2) {
757 		fan1 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN1)
758 			& 0x0d) == 0x09;
759 		fan2 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN2)
760 			& 0x0d) == 0x09;
761 		fan3 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN3)
762 			& 0x0d) == 0x0d;
763 		pwm3 = (smsc47m1_read_value(data, SMSC47M2_REG_PPIN3)
764 			& 0x0d) == 0x08;
765 	} else {
766 		fan1 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(0))
767 			& 0x05) == 0x05;
768 		fan2 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(1))
769 			& 0x05) == 0x05;
770 		fan3 = 0;
771 		pwm3 = 0;
772 	}
773 	if (!(fan1 || fan2 || fan3 || pwm1 || pwm2 || pwm3)) {
774 		dev_warn(dev, "Device not configured, will not use\n");
775 		return -ENODEV;
776 	}
777 
778 	/*
779 	 * Some values (fan min, clock dividers, pwm registers) may be
780 	 * needed before any update is triggered, so we better read them
781 	 * at least once here. We don't usually do it that way, but in
782 	 * this particular case, manually reading 5 registers out of 8
783 	 * doesn't make much sense and we're better using the existing
784 	 * function.
785 	 */
786 	smsc47m1_update_device(dev, 1);
787 
788 	/* Register sysfs hooks */
789 	if (fan1) {
790 		err = sysfs_create_group(&dev->kobj,
791 					 &smsc47m1_group_fan1);
792 		if (err)
793 			goto error_remove_files;
794 	} else
795 		dev_dbg(dev, "Fan 1 not enabled by hardware, skipping\n");
796 
797 	if (fan2) {
798 		err = sysfs_create_group(&dev->kobj,
799 					 &smsc47m1_group_fan2);
800 		if (err)
801 			goto error_remove_files;
802 	} else
803 		dev_dbg(dev, "Fan 2 not enabled by hardware, skipping\n");
804 
805 	if (fan3) {
806 		err = sysfs_create_group(&dev->kobj,
807 					 &smsc47m1_group_fan3);
808 		if (err)
809 			goto error_remove_files;
810 	} else if (data->type == smsc47m2)
811 		dev_dbg(dev, "Fan 3 not enabled by hardware, skipping\n");
812 
813 	if (pwm1) {
814 		err = sysfs_create_group(&dev->kobj,
815 					 &smsc47m1_group_pwm1);
816 		if (err)
817 			goto error_remove_files;
818 	} else
819 		dev_dbg(dev, "PWM 1 not enabled by hardware, skipping\n");
820 
821 	if (pwm2) {
822 		err = sysfs_create_group(&dev->kobj,
823 					 &smsc47m1_group_pwm2);
824 		if (err)
825 			goto error_remove_files;
826 	} else
827 		dev_dbg(dev, "PWM 2 not enabled by hardware, skipping\n");
828 
829 	if (pwm3) {
830 		err = sysfs_create_group(&dev->kobj,
831 					 &smsc47m1_group_pwm3);
832 		if (err)
833 			goto error_remove_files;
834 	} else if (data->type == smsc47m2)
835 		dev_dbg(dev, "PWM 3 not enabled by hardware, skipping\n");
836 
837 	err = sysfs_create_group(&dev->kobj, &smsc47m1_group);
838 	if (err)
839 		goto error_remove_files;
840 
841 	data->hwmon_dev = hwmon_device_register(dev);
842 	if (IS_ERR(data->hwmon_dev)) {
843 		err = PTR_ERR(data->hwmon_dev);
844 		goto error_remove_files;
845 	}
846 
847 	return 0;
848 
849 error_remove_files:
850 	smsc47m1_remove_files(dev);
851 	return err;
852 }
853 
854 static int __exit smsc47m1_remove(struct platform_device *pdev)
855 {
856 	struct smsc47m1_data *data = platform_get_drvdata(pdev);
857 
858 	hwmon_device_unregister(data->hwmon_dev);
859 	smsc47m1_remove_files(&pdev->dev);
860 
861 	return 0;
862 }
863 
864 static struct platform_driver smsc47m1_driver = {
865 	.driver = {
866 		.name	= DRVNAME,
867 	},
868 	.remove		= __exit_p(smsc47m1_remove),
869 };
870 
871 static int __init smsc47m1_device_add(unsigned short address,
872 				      const struct smsc47m1_sio_data *sio_data)
873 {
874 	struct resource res = {
875 		.start	= address,
876 		.end	= address + SMSC_EXTENT - 1,
877 		.name	= DRVNAME,
878 		.flags	= IORESOURCE_IO,
879 	};
880 	int err;
881 
882 	err = smsc47m1_handle_resources(address, sio_data->type, CHECK, NULL);
883 	if (err)
884 		goto exit;
885 
886 	pdev = platform_device_alloc(DRVNAME, address);
887 	if (!pdev) {
888 		err = -ENOMEM;
889 		pr_err("Device allocation failed\n");
890 		goto exit;
891 	}
892 
893 	err = platform_device_add_resources(pdev, &res, 1);
894 	if (err) {
895 		pr_err("Device resource addition failed (%d)\n", err);
896 		goto exit_device_put;
897 	}
898 
899 	err = platform_device_add_data(pdev, sio_data,
900 				       sizeof(struct smsc47m1_sio_data));
901 	if (err) {
902 		pr_err("Platform data allocation failed\n");
903 		goto exit_device_put;
904 	}
905 
906 	err = platform_device_add(pdev);
907 	if (err) {
908 		pr_err("Device addition failed (%d)\n", err);
909 		goto exit_device_put;
910 	}
911 
912 	return 0;
913 
914 exit_device_put:
915 	platform_device_put(pdev);
916 exit:
917 	return err;
918 }
919 
920 static int __init sm_smsc47m1_init(void)
921 {
922 	int err;
923 	unsigned short address;
924 	struct smsc47m1_sio_data sio_data;
925 
926 	err = smsc47m1_find(&sio_data);
927 	if (err < 0)
928 		return err;
929 	address = err;
930 
931 	/* Sets global pdev as a side effect */
932 	err = smsc47m1_device_add(address, &sio_data);
933 	if (err)
934 		return err;
935 
936 	err = platform_driver_probe(&smsc47m1_driver, smsc47m1_probe);
937 	if (err)
938 		goto exit_device;
939 
940 	return 0;
941 
942 exit_device:
943 	platform_device_unregister(pdev);
944 	smsc47m1_restore(&sio_data);
945 	return err;
946 }
947 
948 static void __exit sm_smsc47m1_exit(void)
949 {
950 	platform_driver_unregister(&smsc47m1_driver);
951 	smsc47m1_restore(dev_get_platdata(&pdev->dev));
952 	platform_device_unregister(pdev);
953 }
954 
955 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
956 MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
957 MODULE_LICENSE("GPL");
958 
959 module_init(sm_smsc47m1_init);
960 module_exit(sm_smsc47m1_exit);
961