xref: /openbmc/linux/drivers/hwmon/smsc47m1.c (revision 455f9726)
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 void
77 superio_enter(void)
78 {
79 	outb(0x55, REG);
80 }
81 
82 static inline void
83 superio_exit(void)
84 {
85 	outb(0xAA, REG);
86 }
87 
88 #define SUPERIO_REG_ACT		0x30
89 #define SUPERIO_REG_BASE	0x60
90 #define SUPERIO_REG_DEVID	0x20
91 #define SUPERIO_REG_DEVREV	0x21
92 
93 /* Logical device registers */
94 
95 #define SMSC_EXTENT		0x80
96 
97 /* nr is 0 or 1 in the macros below */
98 #define SMSC47M1_REG_ALARM		0x04
99 #define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
100 #define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
101 #define SMSC47M1_REG_FANDIV		0x58
102 
103 static const u8 SMSC47M1_REG_FAN[3]		= { 0x59, 0x5a, 0x6b };
104 static const u8 SMSC47M1_REG_FAN_PRELOAD[3]	= { 0x5b, 0x5c, 0x6c };
105 static const u8 SMSC47M1_REG_PWM[3]		= { 0x56, 0x57, 0x69 };
106 
107 #define SMSC47M2_REG_ALARM6		0x09
108 #define SMSC47M2_REG_TPIN1		0x38
109 #define SMSC47M2_REG_TPIN2		0x37
110 #define SMSC47M2_REG_TPIN3		0x2d
111 #define SMSC47M2_REG_PPIN3		0x2c
112 #define SMSC47M2_REG_FANDIV3		0x6a
113 
114 #define MIN_FROM_REG(reg, div)		((reg) >= 192 ? 0 : \
115 					 983040 / ((192 - (reg)) * (div)))
116 #define FAN_FROM_REG(reg, div, preload)	((reg) <= (preload) || (reg) == 255 ? \
117 					 0 : \
118 					 983040 / (((reg) - (preload)) * (div)))
119 #define DIV_FROM_REG(reg)		(1 << (reg))
120 #define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
121 #define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
122 #define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)
123 
124 struct smsc47m1_data {
125 	unsigned short addr;
126 	const char *name;
127 	enum chips type;
128 	struct device *hwmon_dev;
129 
130 	struct mutex update_lock;
131 	unsigned long last_updated;	/* In jiffies */
132 
133 	u8 fan[3];		/* Register value */
134 	u8 fan_preload[3];	/* Register value */
135 	u8 fan_div[3];		/* Register encoding, shifted right */
136 	u8 alarms;		/* Register encoding */
137 	u8 pwm[3];		/* Register value (bit 0 is disable) */
138 };
139 
140 struct smsc47m1_sio_data {
141 	enum chips type;
142 	u8 activate;		/* Remember initial device state */
143 };
144 
145 static inline int smsc47m1_read_value(struct smsc47m1_data *data, u8 reg)
146 {
147 	return inb_p(data->addr + reg);
148 }
149 
150 static inline void smsc47m1_write_value(struct smsc47m1_data *data, u8 reg,
151 		u8 value)
152 {
153 	outb_p(value, data->addr + reg);
154 }
155 
156 static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
157 		int init)
158 {
159 	struct smsc47m1_data *data = dev_get_drvdata(dev);
160 
161 	mutex_lock(&data->update_lock);
162 
163 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
164 		int i, fan_nr;
165 		fan_nr = data->type == smsc47m2 ? 3 : 2;
166 
167 		for (i = 0; i < fan_nr; i++) {
168 			data->fan[i] = smsc47m1_read_value(data,
169 				       SMSC47M1_REG_FAN[i]);
170 			data->fan_preload[i] = smsc47m1_read_value(data,
171 					       SMSC47M1_REG_FAN_PRELOAD[i]);
172 			data->pwm[i] = smsc47m1_read_value(data,
173 				       SMSC47M1_REG_PWM[i]);
174 		}
175 
176 		i = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV);
177 		data->fan_div[0] = (i >> 4) & 0x03;
178 		data->fan_div[1] = i >> 6;
179 
180 		data->alarms = smsc47m1_read_value(data,
181 			       SMSC47M1_REG_ALARM) >> 6;
182 		/* Clear alarms if needed */
183 		if (data->alarms)
184 			smsc47m1_write_value(data, SMSC47M1_REG_ALARM, 0xC0);
185 
186 		if (fan_nr >= 3) {
187 			data->fan_div[2] = (smsc47m1_read_value(data,
188 					    SMSC47M2_REG_FANDIV3) >> 4) & 0x03;
189 			data->alarms |= (smsc47m1_read_value(data,
190 					 SMSC47M2_REG_ALARM6) & 0x40) >> 4;
191 			/* Clear alarm if needed */
192 			if (data->alarms & 0x04)
193 				smsc47m1_write_value(data,
194 						     SMSC47M2_REG_ALARM6,
195 						     0x40);
196 		}
197 
198 		data->last_updated = jiffies;
199 	}
200 
201 	mutex_unlock(&data->update_lock);
202 	return data;
203 }
204 
205 static ssize_t get_fan(struct device *dev, struct device_attribute
206 		       *devattr, char *buf)
207 {
208 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
209 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
210 	int nr = attr->index;
211 	/*
212 	 * This chip (stupidly) stops monitoring fan speed if PWM is
213 	 * enabled and duty cycle is 0%. This is fine if the monitoring
214 	 * and control concern the same fan, but troublesome if they are
215 	 * not (which could as well happen).
216 	 */
217 	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
218 		  FAN_FROM_REG(data->fan[nr],
219 			       DIV_FROM_REG(data->fan_div[nr]),
220 			       data->fan_preload[nr]);
221 	return sprintf(buf, "%d\n", rpm);
222 }
223 
224 static ssize_t get_fan_min(struct device *dev, struct device_attribute
225 			   *devattr, char *buf)
226 {
227 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
228 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
229 	int nr = attr->index;
230 	int rpm = MIN_FROM_REG(data->fan_preload[nr],
231 			       DIV_FROM_REG(data->fan_div[nr]));
232 	return sprintf(buf, "%d\n", rpm);
233 }
234 
235 static ssize_t get_fan_div(struct device *dev, struct device_attribute
236 			   *devattr, char *buf)
237 {
238 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
239 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
240 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
241 }
242 
243 static ssize_t get_fan_alarm(struct device *dev, struct device_attribute
244 			     *devattr, char *buf)
245 {
246 	int bitnr = to_sensor_dev_attr(devattr)->index;
247 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
248 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
249 }
250 
251 static ssize_t get_pwm(struct device *dev, struct device_attribute
252 		       *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_FROM_REG(data->pwm[attr->index]));
257 }
258 
259 static ssize_t get_pwm_en(struct device *dev, struct device_attribute
260 			  *devattr, char *buf)
261 {
262 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
263 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
264 	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[attr->index]));
265 }
266 
267 static ssize_t get_alarms(struct device *dev, struct device_attribute
268 			  *devattr, char *buf)
269 {
270 	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
271 	return sprintf(buf, "%d\n", data->alarms);
272 }
273 
274 static ssize_t set_fan_min(struct device *dev, struct device_attribute
275 			   *devattr, const char *buf, size_t count)
276 {
277 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
278 	struct smsc47m1_data *data = dev_get_drvdata(dev);
279 	int nr = attr->index;
280 	long rpmdiv;
281 	long val;
282 	int err;
283 
284 	err = kstrtol(buf, 10, &val);
285 	if (err)
286 		return err;
287 
288 	mutex_lock(&data->update_lock);
289 	rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);
290 
291 	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {
292 		mutex_unlock(&data->update_lock);
293 		return -EINVAL;
294 	}
295 
296 	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
297 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
298 			     data->fan_preload[nr]);
299 	mutex_unlock(&data->update_lock);
300 
301 	return count;
302 }
303 
304 /*
305  * Note: we save and restore the fan minimum here, because its value is
306  * determined in part by the fan clock divider.  This follows the principle
307  * of least surprise; the user doesn't expect the fan minimum to change just
308  * because the divider changed.
309  */
310 static ssize_t set_fan_div(struct device *dev, struct device_attribute
311 			   *devattr, const char *buf, size_t count)
312 {
313 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
314 	struct smsc47m1_data *data = dev_get_drvdata(dev);
315 	int nr = attr->index;
316 	long new_div;
317 	int err;
318 	long tmp;
319 	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);
320 
321 	err = kstrtol(buf, 10, &new_div);
322 	if (err)
323 		return err;
324 
325 	if (new_div == old_div) /* No change */
326 		return count;
327 
328 	mutex_lock(&data->update_lock);
329 	switch (new_div) {
330 	case 1:
331 		data->fan_div[nr] = 0;
332 		break;
333 	case 2:
334 		data->fan_div[nr] = 1;
335 		break;
336 	case 4:
337 		data->fan_div[nr] = 2;
338 		break;
339 	case 8:
340 		data->fan_div[nr] = 3;
341 		break;
342 	default:
343 		mutex_unlock(&data->update_lock);
344 		return -EINVAL;
345 	}
346 
347 	switch (nr) {
348 	case 0:
349 	case 1:
350 		tmp = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV)
351 		      & ~(0x03 << (4 + 2 * nr));
352 		tmp |= data->fan_div[nr] << (4 + 2 * nr);
353 		smsc47m1_write_value(data, SMSC47M1_REG_FANDIV, tmp);
354 		break;
355 	case 2:
356 		tmp = smsc47m1_read_value(data, SMSC47M2_REG_FANDIV3) & 0xCF;
357 		tmp |= data->fan_div[2] << 4;
358 		smsc47m1_write_value(data, SMSC47M2_REG_FANDIV3, tmp);
359 		break;
360 	}
361 
362 	/* Preserve fan min */
363 	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
364 		     + new_div / 2) / new_div;
365 	data->fan_preload[nr] = clamp_val(tmp, 0, 191);
366 	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],
367 			     data->fan_preload[nr]);
368 	mutex_unlock(&data->update_lock);
369 
370 	return count;
371 }
372 
373 static ssize_t set_pwm(struct device *dev, struct device_attribute
374 		       *devattr, const char *buf, size_t count)
375 {
376 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
377 	struct smsc47m1_data *data = dev_get_drvdata(dev);
378 	int nr = attr->index;
379 	long val;
380 	int err;
381 
382 	err = kstrtol(buf, 10, &val);
383 	if (err)
384 		return err;
385 
386 	if (val < 0 || val > 255)
387 		return -EINVAL;
388 
389 	mutex_lock(&data->update_lock);
390 	data->pwm[nr] &= 0x81; /* Preserve additional bits */
391 	data->pwm[nr] |= PWM_TO_REG(val);
392 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
393 			     data->pwm[nr]);
394 	mutex_unlock(&data->update_lock);
395 
396 	return count;
397 }
398 
399 static ssize_t set_pwm_en(struct device *dev, struct device_attribute
400 			  *devattr, const char *buf, size_t count)
401 {
402 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
403 	struct smsc47m1_data *data = dev_get_drvdata(dev);
404 	int nr = attr->index;
405 	unsigned long val;
406 	int err;
407 
408 	err = kstrtoul(buf, 10, &val);
409 	if (err)
410 		return err;
411 
412 	if (val > 1)
413 		return -EINVAL;
414 
415 	mutex_lock(&data->update_lock);
416 	data->pwm[nr] &= 0xFE; /* preserve the other bits */
417 	data->pwm[nr] |= !val;
418 	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],
419 			     data->pwm[nr]);
420 	mutex_unlock(&data->update_lock);
421 
422 	return count;
423 }
424 
425 #define fan_present(offset)						\
426 static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO, get_fan,	\
427 		NULL, offset - 1);					\
428 static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
429 		get_fan_min, set_fan_min, offset - 1);			\
430 static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
431 		get_fan_div, set_fan_div, offset - 1);			\
432 static SENSOR_DEVICE_ATTR(fan##offset##_alarm, S_IRUGO, get_fan_alarm,	\
433 		NULL, offset - 1);					\
434 static SENSOR_DEVICE_ATTR(pwm##offset, S_IRUGO | S_IWUSR,		\
435 		get_pwm, set_pwm, offset - 1);				\
436 static SENSOR_DEVICE_ATTR(pwm##offset##_enable, S_IRUGO | S_IWUSR,	\
437 		get_pwm_en, set_pwm_en, offset - 1)
438 
439 fan_present(1);
440 fan_present(2);
441 fan_present(3);
442 
443 static DEVICE_ATTR(alarms, S_IRUGO, get_alarms, NULL);
444 
445 static ssize_t show_name(struct device *dev, struct device_attribute
446 			 *devattr, char *buf)
447 {
448 	struct smsc47m1_data *data = dev_get_drvdata(dev);
449 
450 	return sprintf(buf, "%s\n", data->name);
451 }
452 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
453 
454 static struct attribute *smsc47m1_attributes_fan1[] = {
455 	&sensor_dev_attr_fan1_input.dev_attr.attr,
456 	&sensor_dev_attr_fan1_min.dev_attr.attr,
457 	&sensor_dev_attr_fan1_div.dev_attr.attr,
458 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
459 	NULL
460 };
461 
462 static const struct attribute_group smsc47m1_group_fan1 = {
463 	.attrs = smsc47m1_attributes_fan1,
464 };
465 
466 static struct attribute *smsc47m1_attributes_fan2[] = {
467 	&sensor_dev_attr_fan2_input.dev_attr.attr,
468 	&sensor_dev_attr_fan2_min.dev_attr.attr,
469 	&sensor_dev_attr_fan2_div.dev_attr.attr,
470 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
471 	NULL
472 };
473 
474 static const struct attribute_group smsc47m1_group_fan2 = {
475 	.attrs = smsc47m1_attributes_fan2,
476 };
477 
478 static struct attribute *smsc47m1_attributes_fan3[] = {
479 	&sensor_dev_attr_fan3_input.dev_attr.attr,
480 	&sensor_dev_attr_fan3_min.dev_attr.attr,
481 	&sensor_dev_attr_fan3_div.dev_attr.attr,
482 	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
483 	NULL
484 };
485 
486 static const struct attribute_group smsc47m1_group_fan3 = {
487 	.attrs = smsc47m1_attributes_fan3,
488 };
489 
490 static struct attribute *smsc47m1_attributes_pwm1[] = {
491 	&sensor_dev_attr_pwm1.dev_attr.attr,
492 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
493 	NULL
494 };
495 
496 static const struct attribute_group smsc47m1_group_pwm1 = {
497 	.attrs = smsc47m1_attributes_pwm1,
498 };
499 
500 static struct attribute *smsc47m1_attributes_pwm2[] = {
501 	&sensor_dev_attr_pwm2.dev_attr.attr,
502 	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
503 	NULL
504 };
505 
506 static const struct attribute_group smsc47m1_group_pwm2 = {
507 	.attrs = smsc47m1_attributes_pwm2,
508 };
509 
510 static struct attribute *smsc47m1_attributes_pwm3[] = {
511 	&sensor_dev_attr_pwm3.dev_attr.attr,
512 	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
513 	NULL
514 };
515 
516 static const struct attribute_group smsc47m1_group_pwm3 = {
517 	.attrs = smsc47m1_attributes_pwm3,
518 };
519 
520 static struct attribute *smsc47m1_attributes[] = {
521 	&dev_attr_alarms.attr,
522 	&dev_attr_name.attr,
523 	NULL
524 };
525 
526 static const struct attribute_group smsc47m1_group = {
527 	.attrs = smsc47m1_attributes,
528 };
529 
530 static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
531 {
532 	u8 val;
533 	unsigned short addr;
534 
535 	superio_enter();
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 		superio_enter();
612 		superio_select();
613 
614 		pr_info("Disabling device\n");
615 		superio_outb(SUPERIO_REG_ACT, sio_data->activate);
616 
617 		superio_exit();
618 	}
619 }
620 
621 #define CHECK		1
622 #define REQUEST		2
623 
624 /*
625  * This function can be used to:
626  *  - test for resource conflicts with ACPI
627  *  - request the resources
628  * We only allocate the I/O ports we really need, to minimize the risk of
629  * conflicts with ACPI or with other drivers.
630  */
631 static int __init smsc47m1_handle_resources(unsigned short address,
632 					    enum chips type, int action,
633 					    struct device *dev)
634 {
635 	static const u8 ports_m1[] = {
636 		/* register, region length */
637 		0x04, 1,
638 		0x33, 4,
639 		0x56, 7,
640 	};
641 
642 	static const u8 ports_m2[] = {
643 		/* register, region length */
644 		0x04, 1,
645 		0x09, 1,
646 		0x2c, 2,
647 		0x35, 4,
648 		0x56, 7,
649 		0x69, 4,
650 	};
651 
652 	int i, ports_size, err;
653 	const u8 *ports;
654 
655 	switch (type) {
656 	case smsc47m1:
657 	default:
658 		ports = ports_m1;
659 		ports_size = ARRAY_SIZE(ports_m1);
660 		break;
661 	case smsc47m2:
662 		ports = ports_m2;
663 		ports_size = ARRAY_SIZE(ports_m2);
664 		break;
665 	}
666 
667 	for (i = 0; i + 1 < ports_size; i += 2) {
668 		unsigned short start = address + ports[i];
669 		unsigned short len = ports[i + 1];
670 
671 		switch (action) {
672 		case CHECK:
673 			/* Only check for conflicts */
674 			err = acpi_check_region(start, len, DRVNAME);
675 			if (err)
676 				return err;
677 			break;
678 		case REQUEST:
679 			/* Request the resources */
680 			if (!devm_request_region(dev, start, len, DRVNAME)) {
681 				dev_err(dev,
682 					"Region 0x%hx-0x%hx already in use!\n",
683 					start, start + len);
684 				return -EBUSY;
685 			}
686 			break;
687 		}
688 	}
689 
690 	return 0;
691 }
692 
693 static void smsc47m1_remove_files(struct device *dev)
694 {
695 	sysfs_remove_group(&dev->kobj, &smsc47m1_group);
696 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan1);
697 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan2);
698 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan3);
699 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm1);
700 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm2);
701 	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm3);
702 }
703 
704 static int __init smsc47m1_probe(struct platform_device *pdev)
705 {
706 	struct device *dev = &pdev->dev;
707 	struct smsc47m1_sio_data *sio_data = dev_get_platdata(dev);
708 	struct smsc47m1_data *data;
709 	struct resource *res;
710 	int err;
711 	int fan1, fan2, fan3, pwm1, pwm2, pwm3;
712 
713 	static const char * const names[] = {
714 		"smsc47m1",
715 		"smsc47m2",
716 	};
717 
718 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
719 	err = smsc47m1_handle_resources(res->start, sio_data->type,
720 					REQUEST, dev);
721 	if (err < 0)
722 		return err;
723 
724 	data = devm_kzalloc(dev, sizeof(struct smsc47m1_data), GFP_KERNEL);
725 	if (!data)
726 		return -ENOMEM;
727 
728 	data->addr = res->start;
729 	data->type = sio_data->type;
730 	data->name = names[sio_data->type];
731 	mutex_init(&data->update_lock);
732 	platform_set_drvdata(pdev, data);
733 
734 	/*
735 	 * If no function is properly configured, there's no point in
736 	 * actually registering the chip.
737 	 */
738 	pwm1 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(0)) & 0x05)
739 	       == 0x04;
740 	pwm2 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(1)) & 0x05)
741 	       == 0x04;
742 	if (data->type == smsc47m2) {
743 		fan1 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN1)
744 			& 0x0d) == 0x09;
745 		fan2 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN2)
746 			& 0x0d) == 0x09;
747 		fan3 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN3)
748 			& 0x0d) == 0x0d;
749 		pwm3 = (smsc47m1_read_value(data, SMSC47M2_REG_PPIN3)
750 			& 0x0d) == 0x08;
751 	} else {
752 		fan1 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(0))
753 			& 0x05) == 0x05;
754 		fan2 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(1))
755 			& 0x05) == 0x05;
756 		fan3 = 0;
757 		pwm3 = 0;
758 	}
759 	if (!(fan1 || fan2 || fan3 || pwm1 || pwm2 || pwm3)) {
760 		dev_warn(dev, "Device not configured, will not use\n");
761 		return -ENODEV;
762 	}
763 
764 	/*
765 	 * Some values (fan min, clock dividers, pwm registers) may be
766 	 * needed before any update is triggered, so we better read them
767 	 * at least once here. We don't usually do it that way, but in
768 	 * this particular case, manually reading 5 registers out of 8
769 	 * doesn't make much sense and we're better using the existing
770 	 * function.
771 	 */
772 	smsc47m1_update_device(dev, 1);
773 
774 	/* Register sysfs hooks */
775 	if (fan1) {
776 		err = sysfs_create_group(&dev->kobj,
777 					 &smsc47m1_group_fan1);
778 		if (err)
779 			goto error_remove_files;
780 	} else
781 		dev_dbg(dev, "Fan 1 not enabled by hardware, skipping\n");
782 
783 	if (fan2) {
784 		err = sysfs_create_group(&dev->kobj,
785 					 &smsc47m1_group_fan2);
786 		if (err)
787 			goto error_remove_files;
788 	} else
789 		dev_dbg(dev, "Fan 2 not enabled by hardware, skipping\n");
790 
791 	if (fan3) {
792 		err = sysfs_create_group(&dev->kobj,
793 					 &smsc47m1_group_fan3);
794 		if (err)
795 			goto error_remove_files;
796 	} else if (data->type == smsc47m2)
797 		dev_dbg(dev, "Fan 3 not enabled by hardware, skipping\n");
798 
799 	if (pwm1) {
800 		err = sysfs_create_group(&dev->kobj,
801 					 &smsc47m1_group_pwm1);
802 		if (err)
803 			goto error_remove_files;
804 	} else
805 		dev_dbg(dev, "PWM 1 not enabled by hardware, skipping\n");
806 
807 	if (pwm2) {
808 		err = sysfs_create_group(&dev->kobj,
809 					 &smsc47m1_group_pwm2);
810 		if (err)
811 			goto error_remove_files;
812 	} else
813 		dev_dbg(dev, "PWM 2 not enabled by hardware, skipping\n");
814 
815 	if (pwm3) {
816 		err = sysfs_create_group(&dev->kobj,
817 					 &smsc47m1_group_pwm3);
818 		if (err)
819 			goto error_remove_files;
820 	} else if (data->type == smsc47m2)
821 		dev_dbg(dev, "PWM 3 not enabled by hardware, skipping\n");
822 
823 	err = sysfs_create_group(&dev->kobj, &smsc47m1_group);
824 	if (err)
825 		goto error_remove_files;
826 
827 	data->hwmon_dev = hwmon_device_register(dev);
828 	if (IS_ERR(data->hwmon_dev)) {
829 		err = PTR_ERR(data->hwmon_dev);
830 		goto error_remove_files;
831 	}
832 
833 	return 0;
834 
835 error_remove_files:
836 	smsc47m1_remove_files(dev);
837 	return err;
838 }
839 
840 static int __exit smsc47m1_remove(struct platform_device *pdev)
841 {
842 	struct smsc47m1_data *data = platform_get_drvdata(pdev);
843 
844 	hwmon_device_unregister(data->hwmon_dev);
845 	smsc47m1_remove_files(&pdev->dev);
846 
847 	return 0;
848 }
849 
850 static struct platform_driver smsc47m1_driver = {
851 	.driver = {
852 		.owner	= THIS_MODULE,
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