xref: /openbmc/linux/drivers/hwmon/smsc47m1.c (revision a61127c2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * smsc47m1.c - Part of lm_sensors, Linux kernel modules
4  *		for hardware monitoring
5  *
6  * Supports the SMSC LPC47B27x, LPC47M10x, LPC47M112, LPC47M13x,
7  * LPC47M14x, LPC47M15x, LPC47M192, LPC47M292 and LPC47M997
8  * Super-I/O chips.
9  *
10  * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
11  * Copyright (C) 2004-2007 Jean Delvare <jdelvare@suse.de>
12  * Ported to Linux 2.6 by Gabriele Gorla <gorlik@yahoo.com>
13  *			and Jean Delvare
14  */
15 
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 
18 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <linux/ioport.h>
21 #include <linux/jiffies.h>
22 #include <linux/platform_device.h>
23 #include <linux/hwmon.h>
24 #include <linux/hwmon-sysfs.h>
25 #include <linux/err.h>
26 #include <linux/init.h>
27 #include <linux/mutex.h>
28 #include <linux/sysfs.h>
29 #include <linux/acpi.h>
30 #include <linux/io.h>
31 
32 static unsigned short force_id;
33 module_param(force_id, ushort, 0);
34 MODULE_PARM_DESC(force_id, "Override the detected device ID");
35 
36 static struct platform_device *pdev;
37 
38 #define DRVNAME "smsc47m1"
39 enum chips { smsc47m1, smsc47m2 };
40 
41 /* Super-I/0 registers and commands */
42 
43 #define REG	0x2e	/* The register to read/write */
44 #define VAL	0x2f	/* The value to read/write */
45 
46 static inline void
47 superio_outb(int reg, int val)
48 {
49 	outb(reg, REG);
50 	outb(val, VAL);
51 }
52 
53 static inline int
54 superio_inb(int reg)
55 {
56 	outb(reg, REG);
57 	return inb(VAL);
58 }
59 
60 /* logical device for fans is 0x0A */
61 #define superio_select() superio_outb(0x07, 0x0A)
62 
63 static inline int
64 superio_enter(void)
65 {
66 	if (!request_muxed_region(REG, 2, DRVNAME))
67 		return -EBUSY;
68 
69 	outb(0x55, REG);
70 	return 0;
71 }
72 
73 static inline void
74 superio_exit(void)
75 {
76 	outb(0xAA, REG);
77 	release_region(REG, 2);
78 }
79 
80 #define SUPERIO_REG_ACT		0x30
81 #define SUPERIO_REG_BASE	0x60
82 #define SUPERIO_REG_DEVID	0x20
83 #define SUPERIO_REG_DEVREV	0x21
84 
85 /* Logical device registers */
86 
87 #define SMSC_EXTENT		0x80
88 
89 /* nr is 0 or 1 in the macros below */
90 #define SMSC47M1_REG_ALARM		0x04
91 #define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
92 #define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
93 #define SMSC47M1_REG_FANDIV		0x58
94 
95 static const u8 SMSC47M1_REG_FAN[3]		= { 0x59, 0x5a, 0x6b };
96 static const u8 SMSC47M1_REG_FAN_PRELOAD[3]	= { 0x5b, 0x5c, 0x6c };
97 static const u8 SMSC47M1_REG_PWM[3]		= { 0x56, 0x57, 0x69 };
98 
99 #define SMSC47M2_REG_ALARM6		0x09
100 #define SMSC47M2_REG_TPIN1		0x38
101 #define SMSC47M2_REG_TPIN2		0x37
102 #define SMSC47M2_REG_TPIN3		0x2d
103 #define SMSC47M2_REG_PPIN3		0x2c
104 #define SMSC47M2_REG_FANDIV3		0x6a
105 
106 #define MIN_FROM_REG(reg, div)		((reg) >= 192 ? 0 : \
107 					 983040 / ((192 - (reg)) * (div)))
108 #define FAN_FROM_REG(reg, div, preload)	((reg) <= (preload) || (reg) == 255 ? \
109 					 0 : \
110 					 983040 / (((reg) - (preload)) * (div)))
111 #define DIV_FROM_REG(reg)		(1 << (reg))
112 #define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
113 #define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
114 #define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)
115 
116 struct smsc47m1_data {
117 	unsigned short addr;
118 	const char *name;
119 	enum chips type;
120 	struct device *hwmon_dev;
121 
122 	struct mutex update_lock;
123 	unsigned long last_updated;	/* In jiffies */
124 
125 	u8 fan[3];		/* Register value */
126 	u8 fan_preload[3];	/* Register value */
127 	u8 fan_div[3];		/* Register encoding, shifted right */
128 	u8 alarms;		/* Register encoding */
129 	u8 pwm[3];		/* Register value (bit 0 is disable) */
130 };
131 
132 struct smsc47m1_sio_data {
133 	enum chips type;
134 	u8 activate;		/* Remember initial device state */
135 };
136 
137 static inline int smsc47m1_read_value(struct smsc47m1_data *data, u8 reg)
138 {
139 	return inb_p(data->addr + reg);
140 }
141 
142 static inline void smsc47m1_write_value(struct smsc47m1_data *data, u8 reg,
143 		u8 value)
144 {
145 	outb_p(value, data->addr + reg);
146 }
147 
148 static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
149 		int init)
150 {
151 	struct smsc47m1_data *data = dev_get_drvdata(dev);
152 
153 	mutex_lock(&data->update_lock);
154 
155 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
156 		int i, fan_nr;
157 		fan_nr = data->type == smsc47m2 ? 3 : 2;
158 
159 		for (i = 0; i < fan_nr; i++) {
160 			data->fan[i] = smsc47m1_read_value(data,
161 				       SMSC47M1_REG_FAN[i]);
162 			data->fan_preload[i] = smsc47m1_read_value(data,
163 					       SMSC47M1_REG_FAN_PRELOAD[i]);
164 			data->pwm[i] = smsc47m1_read_value(data,
165 				       SMSC47M1_REG_PWM[i]);
166 		}
167 
168 		i = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV);
169 		data->fan_div[0] = (i >> 4) & 0x03;
170 		data->fan_div[1] = i >> 6;
171 
172 		data->alarms = smsc47m1_read_value(data,
173 			       SMSC47M1_REG_ALARM) >> 6;
174 		/* Clear alarms if needed */
175 		if (data->alarms)
176 			smsc47m1_write_value(data, SMSC47M1_REG_ALARM, 0xC0);
177 
178 		if (fan_nr >= 3) {
179 			data->fan_div[2] = (smsc47m1_read_value(data,
180 					    SMSC47M2_REG_FANDIV3) >> 4) & 0x03;
181 			data->alarms |= (smsc47m1_read_value(data,
182 					 SMSC47M2_REG_ALARM6) & 0x40) >> 4;
183 			/* Clear alarm if needed */
184 			if (data->alarms & 0x04)
185 				smsc47m1_write_value(data,
186 						     SMSC47M2_REG_ALARM6,
187 						     0x40);
188 		}
189 
190 		data->last_updated = jiffies;
191 	}
192 
193 	mutex_unlock(&data->update_lock);
194 	return data;
195 }
196 
197 static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
198 			char *buf)
199 {
200 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
201 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
202 	int nr = attr->index;
203 	/*
204 	 * This chip (stupidly) stops monitoring fan speed if PWM is
205 	 * enabled and duty cycle is 0%. This is fine if the monitoring
206 	 * and control concern the same fan, but troublesome if they are
207 	 * not (which could as well happen).
208 	 */
209 	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
210 		  FAN_FROM_REG(data->fan[nr],
211 			       DIV_FROM_REG(data->fan_div[nr]),
212 			       data->fan_preload[nr]);
213 	return sprintf(buf, "%d\n", rpm);
214 }
215 
216 static ssize_t fan_min_show(struct device *dev,
217 			    struct device_attribute *devattr, char *buf)
218 {
219 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
220 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
221 	int nr = attr->index;
222 	int rpm = MIN_FROM_REG(data->fan_preload[nr],
223 			       DIV_FROM_REG(data->fan_div[nr]));
224 	return sprintf(buf, "%d\n", rpm);
225 }
226 
227 static ssize_t fan_div_show(struct device *dev,
228 			    struct device_attribute *devattr, char *buf)
229 {
230 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
231 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
232 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
233 }
234 
235 static ssize_t fan_alarm_show(struct device *dev,
236 			      struct device_attribute *devattr, char *buf)
237 {
238 	int bitnr = to_sensor_dev_attr(devattr)->index;
239 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
240 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
241 }
242 
243 static ssize_t pwm_show(struct device *dev, struct device_attribute *devattr,
244 			char *buf)
245 {
246 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
247 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
248 	return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[attr->index]));
249 }
250 
251 static ssize_t pwm_en_show(struct device *dev,
252 			   struct device_attribute *devattr, char *buf)
253 {
254 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
255 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
256 	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[attr->index]));
257 }
258 
259 static ssize_t alarms_show(struct device *dev,
260 			   struct device_attribute *devattr, char *buf)
261 {
262 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
263 	return sprintf(buf, "%d\n", data->alarms);
264 }
265 
266 static ssize_t fan_min_store(struct device *dev,
267 			     struct device_attribute *devattr,
268 			     const char *buf, size_t count)
269 {
270 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
271 	struct smsc47m1_data *data = dev_get_drvdata(dev);
272 	int nr = attr->index;
273 	long rpmdiv;
274 	long val;
275 	int err;
276 
277 	err = kstrtol(buf, 10, &val);
278 	if (err)
279 		return err;
280 
281 	mutex_lock(&data->update_lock);
282 	rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);
283 
284 	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {
285 		mutex_unlock(&data->update_lock);
286 		return -EINVAL;
287 	}
288 
289 	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
290 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
291 			     data->fan_preload[nr]);
292 	mutex_unlock(&data->update_lock);
293 
294 	return count;
295 }
296 
297 /*
298  * Note: we save and restore the fan minimum here, because its value is
299  * determined in part by the fan clock divider.  This follows the principle
300  * of least surprise; the user doesn't expect the fan minimum to change just
301  * because the divider changed.
302  */
303 static ssize_t fan_div_store(struct device *dev,
304 			     struct device_attribute *devattr,
305 			     const char *buf, size_t count)
306 {
307 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
308 	struct smsc47m1_data *data = dev_get_drvdata(dev);
309 	int nr = attr->index;
310 	long new_div;
311 	int err;
312 	long tmp;
313 	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);
314 
315 	err = kstrtol(buf, 10, &new_div);
316 	if (err)
317 		return err;
318 
319 	if (new_div == old_div) /* No change */
320 		return count;
321 
322 	mutex_lock(&data->update_lock);
323 	switch (new_div) {
324 	case 1:
325 		data->fan_div[nr] = 0;
326 		break;
327 	case 2:
328 		data->fan_div[nr] = 1;
329 		break;
330 	case 4:
331 		data->fan_div[nr] = 2;
332 		break;
333 	case 8:
334 		data->fan_div[nr] = 3;
335 		break;
336 	default:
337 		mutex_unlock(&data->update_lock);
338 		return -EINVAL;
339 	}
340 
341 	switch (nr) {
342 	case 0:
343 	case 1:
344 		tmp = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV)
345 		      & ~(0x03 << (4 + 2 * nr));
346 		tmp |= data->fan_div[nr] << (4 + 2 * nr);
347 		smsc47m1_write_value(data, SMSC47M1_REG_FANDIV, tmp);
348 		break;
349 	case 2:
350 		tmp = smsc47m1_read_value(data, SMSC47M2_REG_FANDIV3) & 0xCF;
351 		tmp |= data->fan_div[2] << 4;
352 		smsc47m1_write_value(data, SMSC47M2_REG_FANDIV3, tmp);
353 		break;
354 	}
355 
356 	/* Preserve fan min */
357 	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
358 		     + new_div / 2) / new_div;
359 	data->fan_preload[nr] = clamp_val(tmp, 0, 191);
360 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
361 			     data->fan_preload[nr]);
362 	mutex_unlock(&data->update_lock);
363 
364 	return count;
365 }
366 
367 static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
368 			 const char *buf, size_t count)
369 {
370 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
371 	struct smsc47m1_data *data = dev_get_drvdata(dev);
372 	int nr = attr->index;
373 	long val;
374 	int err;
375 
376 	err = kstrtol(buf, 10, &val);
377 	if (err)
378 		return err;
379 
380 	if (val < 0 || val > 255)
381 		return -EINVAL;
382 
383 	mutex_lock(&data->update_lock);
384 	data->pwm[nr] &= 0x81; /* Preserve additional bits */
385 	data->pwm[nr] |= PWM_TO_REG(val);
386 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
387 			     data->pwm[nr]);
388 	mutex_unlock(&data->update_lock);
389 
390 	return count;
391 }
392 
393 static ssize_t pwm_en_store(struct device *dev,
394 			    struct device_attribute *devattr, const char *buf,
395 			    size_t count)
396 {
397 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
398 	struct smsc47m1_data *data = dev_get_drvdata(dev);
399 	int nr = attr->index;
400 	unsigned long val;
401 	int err;
402 
403 	err = kstrtoul(buf, 10, &val);
404 	if (err)
405 		return err;
406 
407 	if (val > 1)
408 		return -EINVAL;
409 
410 	mutex_lock(&data->update_lock);
411 	data->pwm[nr] &= 0xFE; /* preserve the other bits */
412 	data->pwm[nr] |= !val;
413 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
414 			     data->pwm[nr]);
415 	mutex_unlock(&data->update_lock);
416 
417 	return count;
418 }
419 
420 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
421 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
422 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
423 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, fan_alarm, 0);
424 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0);
425 static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm_en, 0);
426 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
427 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
428 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
429 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, fan_alarm, 1);
430 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1);
431 static SENSOR_DEVICE_ATTR_RW(pwm2_enable, pwm_en, 1);
432 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
433 static SENSOR_DEVICE_ATTR_RW(fan3_min, fan_min, 2);
434 static SENSOR_DEVICE_ATTR_RW(fan3_div, fan_div, 2);
435 static SENSOR_DEVICE_ATTR_RO(fan3_alarm, fan_alarm, 2);
436 static SENSOR_DEVICE_ATTR_RW(pwm3, pwm, 2);
437 static SENSOR_DEVICE_ATTR_RW(pwm3_enable, pwm_en, 2);
438 
439 static DEVICE_ATTR_RO(alarms);
440 
441 static ssize_t name_show(struct device *dev, struct device_attribute
442 			 *devattr, char *buf)
443 {
444 	struct smsc47m1_data *data = dev_get_drvdata(dev);
445 
446 	return sprintf(buf, "%s\n", data->name);
447 }
448 static DEVICE_ATTR_RO(name);
449 
450 static struct attribute *smsc47m1_attributes_fan1[] = {
451 	&sensor_dev_attr_fan1_input.dev_attr.attr,
452 	&sensor_dev_attr_fan1_min.dev_attr.attr,
453 	&sensor_dev_attr_fan1_div.dev_attr.attr,
454 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
455 	NULL
456 };
457 
458 static const struct attribute_group smsc47m1_group_fan1 = {
459 	.attrs = smsc47m1_attributes_fan1,
460 };
461 
462 static struct attribute *smsc47m1_attributes_fan2[] = {
463 	&sensor_dev_attr_fan2_input.dev_attr.attr,
464 	&sensor_dev_attr_fan2_min.dev_attr.attr,
465 	&sensor_dev_attr_fan2_div.dev_attr.attr,
466 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
467 	NULL
468 };
469 
470 static const struct attribute_group smsc47m1_group_fan2 = {
471 	.attrs = smsc47m1_attributes_fan2,
472 };
473 
474 static struct attribute *smsc47m1_attributes_fan3[] = {
475 	&sensor_dev_attr_fan3_input.dev_attr.attr,
476 	&sensor_dev_attr_fan3_min.dev_attr.attr,
477 	&sensor_dev_attr_fan3_div.dev_attr.attr,
478 	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
479 	NULL
480 };
481 
482 static const struct attribute_group smsc47m1_group_fan3 = {
483 	.attrs = smsc47m1_attributes_fan3,
484 };
485 
486 static struct attribute *smsc47m1_attributes_pwm1[] = {
487 	&sensor_dev_attr_pwm1.dev_attr.attr,
488 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
489 	NULL
490 };
491 
492 static const struct attribute_group smsc47m1_group_pwm1 = {
493 	.attrs = smsc47m1_attributes_pwm1,
494 };
495 
496 static struct attribute *smsc47m1_attributes_pwm2[] = {
497 	&sensor_dev_attr_pwm2.dev_attr.attr,
498 	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
499 	NULL
500 };
501 
502 static const struct attribute_group smsc47m1_group_pwm2 = {
503 	.attrs = smsc47m1_attributes_pwm2,
504 };
505 
506 static struct attribute *smsc47m1_attributes_pwm3[] = {
507 	&sensor_dev_attr_pwm3.dev_attr.attr,
508 	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
509 	NULL
510 };
511 
512 static const struct attribute_group smsc47m1_group_pwm3 = {
513 	.attrs = smsc47m1_attributes_pwm3,
514 };
515 
516 static struct attribute *smsc47m1_attributes[] = {
517 	&dev_attr_alarms.attr,
518 	&dev_attr_name.attr,
519 	NULL
520 };
521 
522 static const struct attribute_group smsc47m1_group = {
523 	.attrs = smsc47m1_attributes,
524 };
525 
526 static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
527 {
528 	u8 val;
529 	unsigned short addr;
530 	int err;
531 
532 	err = superio_enter();
533 	if (err)
534 		return err;
535 
536 	val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
537 
538 	/*
539 	 * SMSC LPC47M10x/LPC47M112/LPC47M13x (device id 0x59), LPC47M14x
540 	 * (device id 0x5F) and LPC47B27x (device id 0x51) have fan control.
541 	 * The LPC47M15x and LPC47M192 chips "with hardware monitoring block"
542 	 * can do much more besides (device id 0x60).
543 	 * The LPC47M997 is undocumented, but seems to be compatible with
544 	 * the LPC47M192, and has the same device id.
545 	 * The LPC47M292 (device id 0x6B) is somewhat compatible, but it
546 	 * supports a 3rd fan, and the pin configuration registers are
547 	 * unfortunately different.
548 	 * The LPC47M233 has the same device id (0x6B) but is not compatible.
549 	 * We check the high bit of the device revision register to
550 	 * differentiate them.
551 	 */
552 	switch (val) {
553 	case 0x51:
554 		pr_info("Found SMSC LPC47B27x\n");
555 		sio_data->type = smsc47m1;
556 		break;
557 	case 0x59:
558 		pr_info("Found SMSC LPC47M10x/LPC47M112/LPC47M13x\n");
559 		sio_data->type = smsc47m1;
560 		break;
561 	case 0x5F:
562 		pr_info("Found SMSC LPC47M14x\n");
563 		sio_data->type = smsc47m1;
564 		break;
565 	case 0x60:
566 		pr_info("Found SMSC LPC47M15x/LPC47M192/LPC47M997\n");
567 		sio_data->type = smsc47m1;
568 		break;
569 	case 0x6B:
570 		if (superio_inb(SUPERIO_REG_DEVREV) & 0x80) {
571 			pr_debug("Found SMSC LPC47M233, unsupported\n");
572 			superio_exit();
573 			return -ENODEV;
574 		}
575 
576 		pr_info("Found SMSC LPC47M292\n");
577 		sio_data->type = smsc47m2;
578 		break;
579 	default:
580 		superio_exit();
581 		return -ENODEV;
582 	}
583 
584 	superio_select();
585 	addr = (superio_inb(SUPERIO_REG_BASE) << 8)
586 	      |  superio_inb(SUPERIO_REG_BASE + 1);
587 	if (addr == 0) {
588 		pr_info("Device address not set, will not use\n");
589 		superio_exit();
590 		return -ENODEV;
591 	}
592 
593 	/*
594 	 * Enable only if address is set (needed at least on the
595 	 * Compaq Presario S4000NX)
596 	 */
597 	sio_data->activate = superio_inb(SUPERIO_REG_ACT);
598 	if ((sio_data->activate & 0x01) == 0) {
599 		pr_info("Enabling device\n");
600 		superio_outb(SUPERIO_REG_ACT, sio_data->activate | 0x01);
601 	}
602 
603 	superio_exit();
604 	return addr;
605 }
606 
607 /* Restore device to its initial state */
608 static void smsc47m1_restore(const struct smsc47m1_sio_data *sio_data)
609 {
610 	if ((sio_data->activate & 0x01) == 0) {
611 		if (!superio_enter()) {
612 			superio_select();
613 			pr_info("Disabling device\n");
614 			superio_outb(SUPERIO_REG_ACT, sio_data->activate);
615 			superio_exit();
616 		} else {
617 			pr_warn("Failed to disable device\n");
618 		}
619 	}
620 }
621 
622 #define CHECK		1
623 #define REQUEST		2
624 
625 /*
626  * This function can be used to:
627  *  - test for resource conflicts with ACPI
628  *  - request the resources
629  * We only allocate the I/O ports we really need, to minimize the risk of
630  * conflicts with ACPI or with other drivers.
631  */
632 static int __init smsc47m1_handle_resources(unsigned short address,
633 					    enum chips type, int action,
634 					    struct device *dev)
635 {
636 	static const u8 ports_m1[] = {
637 		/* register, region length */
638 		0x04, 1,
639 		0x33, 4,
640 		0x56, 7,
641 	};
642 
643 	static const u8 ports_m2[] = {
644 		/* register, region length */
645 		0x04, 1,
646 		0x09, 1,
647 		0x2c, 2,
648 		0x35, 4,
649 		0x56, 7,
650 		0x69, 4,
651 	};
652 
653 	int i, ports_size, err;
654 	const u8 *ports;
655 
656 	switch (type) {
657 	case smsc47m1:
658 	default:
659 		ports = ports_m1;
660 		ports_size = ARRAY_SIZE(ports_m1);
661 		break;
662 	case smsc47m2:
663 		ports = ports_m2;
664 		ports_size = ARRAY_SIZE(ports_m2);
665 		break;
666 	}
667 
668 	for (i = 0; i + 1 < ports_size; i += 2) {
669 		unsigned short start = address + ports[i];
670 		unsigned short len = ports[i + 1];
671 
672 		switch (action) {
673 		case CHECK:
674 			/* Only check for conflicts */
675 			err = acpi_check_region(start, len, DRVNAME);
676 			if (err)
677 				return err;
678 			break;
679 		case REQUEST:
680 			/* Request the resources */
681 			if (!devm_request_region(dev, start, len, DRVNAME)) {
682 				dev_err(dev,
683 					"Region 0x%hx-0x%hx already in use!\n",
684 					start, start + len);
685 				return -EBUSY;
686 			}
687 			break;
688 		}
689 	}
690 
691 	return 0;
692 }
693 
694 static void smsc47m1_remove_files(struct device *dev)
695 {
696 	sysfs_remove_group(&dev->kobj, &smsc47m1_group);
697 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan1);
698 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan2);
699 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan3);
700 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm1);
701 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm2);
702 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm3);
703 }
704 
705 static int __init smsc47m1_probe(struct platform_device *pdev)
706 {
707 	struct device *dev = &pdev->dev;
708 	struct smsc47m1_sio_data *sio_data = dev_get_platdata(dev);
709 	struct smsc47m1_data *data;
710 	struct resource *res;
711 	int err;
712 	int fan1, fan2, fan3, pwm1, pwm2, pwm3;
713 
714 	static const char * const names[] = {
715 		"smsc47m1",
716 		"smsc47m2",
717 	};
718 
719 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
720 	err = smsc47m1_handle_resources(res->start, sio_data->type,
721 					REQUEST, dev);
722 	if (err < 0)
723 		return err;
724 
725 	data = devm_kzalloc(dev, sizeof(struct smsc47m1_data), GFP_KERNEL);
726 	if (!data)
727 		return -ENOMEM;
728 
729 	data->addr = res->start;
730 	data->type = sio_data->type;
731 	data->name = names[sio_data->type];
732 	mutex_init(&data->update_lock);
733 	platform_set_drvdata(pdev, data);
734 
735 	/*
736 	 * If no function is properly configured, there's no point in
737 	 * actually registering the chip.
738 	 */
739 	pwm1 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(0)) & 0x05)
740 	       == 0x04;
741 	pwm2 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(1)) & 0x05)
742 	       == 0x04;
743 	if (data->type == smsc47m2) {
744 		fan1 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN1)
745 			& 0x0d) == 0x09;
746 		fan2 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN2)
747 			& 0x0d) == 0x09;
748 		fan3 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN3)
749 			& 0x0d) == 0x0d;
750 		pwm3 = (smsc47m1_read_value(data, SMSC47M2_REG_PPIN3)
751 			& 0x0d) == 0x08;
752 	} else {
753 		fan1 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(0))
754 			& 0x05) == 0x05;
755 		fan2 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(1))
756 			& 0x05) == 0x05;
757 		fan3 = 0;
758 		pwm3 = 0;
759 	}
760 	if (!(fan1 || fan2 || fan3 || pwm1 || pwm2 || pwm3)) {
761 		dev_warn(dev, "Device not configured, will not use\n");
762 		return -ENODEV;
763 	}
764 
765 	/*
766 	 * Some values (fan min, clock dividers, pwm registers) may be
767 	 * needed before any update is triggered, so we better read them
768 	 * at least once here. We don't usually do it that way, but in
769 	 * this particular case, manually reading 5 registers out of 8
770 	 * doesn't make much sense and we're better using the existing
771 	 * function.
772 	 */
773 	smsc47m1_update_device(dev, 1);
774 
775 	/* Register sysfs hooks */
776 	if (fan1) {
777 		err = sysfs_create_group(&dev->kobj,
778 					 &smsc47m1_group_fan1);
779 		if (err)
780 			goto error_remove_files;
781 	} else
782 		dev_dbg(dev, "Fan 1 not enabled by hardware, skipping\n");
783 
784 	if (fan2) {
785 		err = sysfs_create_group(&dev->kobj,
786 					 &smsc47m1_group_fan2);
787 		if (err)
788 			goto error_remove_files;
789 	} else
790 		dev_dbg(dev, "Fan 2 not enabled by hardware, skipping\n");
791 
792 	if (fan3) {
793 		err = sysfs_create_group(&dev->kobj,
794 					 &smsc47m1_group_fan3);
795 		if (err)
796 			goto error_remove_files;
797 	} else if (data->type == smsc47m2)
798 		dev_dbg(dev, "Fan 3 not enabled by hardware, skipping\n");
799 
800 	if (pwm1) {
801 		err = sysfs_create_group(&dev->kobj,
802 					 &smsc47m1_group_pwm1);
803 		if (err)
804 			goto error_remove_files;
805 	} else
806 		dev_dbg(dev, "PWM 1 not enabled by hardware, skipping\n");
807 
808 	if (pwm2) {
809 		err = sysfs_create_group(&dev->kobj,
810 					 &smsc47m1_group_pwm2);
811 		if (err)
812 			goto error_remove_files;
813 	} else
814 		dev_dbg(dev, "PWM 2 not enabled by hardware, skipping\n");
815 
816 	if (pwm3) {
817 		err = sysfs_create_group(&dev->kobj,
818 					 &smsc47m1_group_pwm3);
819 		if (err)
820 			goto error_remove_files;
821 	} else if (data->type == smsc47m2)
822 		dev_dbg(dev, "PWM 3 not enabled by hardware, skipping\n");
823 
824 	err = sysfs_create_group(&dev->kobj, &smsc47m1_group);
825 	if (err)
826 		goto error_remove_files;
827 
828 	data->hwmon_dev = hwmon_device_register(dev);
829 	if (IS_ERR(data->hwmon_dev)) {
830 		err = PTR_ERR(data->hwmon_dev);
831 		goto error_remove_files;
832 	}
833 
834 	return 0;
835 
836 error_remove_files:
837 	smsc47m1_remove_files(dev);
838 	return err;
839 }
840 
841 static int __exit smsc47m1_remove(struct platform_device *pdev)
842 {
843 	struct smsc47m1_data *data = platform_get_drvdata(pdev);
844 
845 	hwmon_device_unregister(data->hwmon_dev);
846 	smsc47m1_remove_files(&pdev->dev);
847 
848 	return 0;
849 }
850 
851 static struct platform_driver smsc47m1_driver = {
852 	.driver = {
853 		.name	= DRVNAME,
854 	},
855 	.remove		= __exit_p(smsc47m1_remove),
856 };
857 
858 static int __init smsc47m1_device_add(unsigned short address,
859 				      const struct smsc47m1_sio_data *sio_data)
860 {
861 	struct resource res = {
862 		.start	= address,
863 		.end	= address + SMSC_EXTENT - 1,
864 		.name	= DRVNAME,
865 		.flags	= IORESOURCE_IO,
866 	};
867 	int err;
868 
869 	err = smsc47m1_handle_resources(address, sio_data->type, CHECK, NULL);
870 	if (err)
871 		goto exit;
872 
873 	pdev = platform_device_alloc(DRVNAME, address);
874 	if (!pdev) {
875 		err = -ENOMEM;
876 		pr_err("Device allocation failed\n");
877 		goto exit;
878 	}
879 
880 	err = platform_device_add_resources(pdev, &res, 1);
881 	if (err) {
882 		pr_err("Device resource addition failed (%d)\n", err);
883 		goto exit_device_put;
884 	}
885 
886 	err = platform_device_add_data(pdev, sio_data,
887 				       sizeof(struct smsc47m1_sio_data));
888 	if (err) {
889 		pr_err("Platform data allocation failed\n");
890 		goto exit_device_put;
891 	}
892 
893 	err = platform_device_add(pdev);
894 	if (err) {
895 		pr_err("Device addition failed (%d)\n", err);
896 		goto exit_device_put;
897 	}
898 
899 	return 0;
900 
901 exit_device_put:
902 	platform_device_put(pdev);
903 exit:
904 	return err;
905 }
906 
907 static int __init sm_smsc47m1_init(void)
908 {
909 	int err;
910 	unsigned short address;
911 	struct smsc47m1_sio_data sio_data;
912 
913 	err = smsc47m1_find(&sio_data);
914 	if (err < 0)
915 		return err;
916 	address = err;
917 
918 	/* Sets global pdev as a side effect */
919 	err = smsc47m1_device_add(address, &sio_data);
920 	if (err)
921 		return err;
922 
923 	err = platform_driver_probe(&smsc47m1_driver, smsc47m1_probe);
924 	if (err)
925 		goto exit_device;
926 
927 	return 0;
928 
929 exit_device:
930 	platform_device_unregister(pdev);
931 	smsc47m1_restore(&sio_data);
932 	return err;
933 }
934 
935 static void __exit sm_smsc47m1_exit(void)
936 {
937 	platform_driver_unregister(&smsc47m1_driver);
938 	smsc47m1_restore(dev_get_platdata(&pdev->dev));
939 	platform_device_unregister(pdev);
940 }
941 
942 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
943 MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
944 MODULE_LICENSE("GPL");
945 
946 module_init(sm_smsc47m1_init);
947 module_exit(sm_smsc47m1_exit);
948