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1/*
2 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring.
4 *
5 * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de>
6 *
7 * based on code written by John Morris <john.morris@spirentcom.com>
8 * Copyright (c) 2003 Spirent Communications
9 * and Claus Gindhart <claus.gindhart@kontron.com>
10 *
11 * This module has only been tested with the MAX6650 chip. It should
12 * also work with the MAX6651. It does not distinguish max6650 and max6651
13 * chips.
14 *
15 * The datasheet was last seen at:
16 *
17 * http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
18 *
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
23 *
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
32 */
33
34#include <linux/module.h>
35#include <linux/init.h>
36#include <linux/slab.h>
37#include <linux/jiffies.h>
38#include <linux/i2c.h>
39#include <linux/hwmon.h>
40#include <linux/hwmon-sysfs.h>
41#include <linux/err.h>
42
43/*
44 * Insmod parameters
45 */
46
47/* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
48static int fan_voltage;
49/* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
50static int prescaler;
51/* clock: The clock frequency of the chip the driver should assume */
52static int clock = 254000;
53
54module_param(fan_voltage, int, S_IRUGO);
55module_param(prescaler, int, S_IRUGO);
56module_param(clock, int, S_IRUGO);
57
58/*
59 * MAX 6650/6651 registers
60 */
61
62#define MAX6650_REG_SPEED 0x00
63#define MAX6650_REG_CONFIG 0x02
64#define MAX6650_REG_GPIO_DEF 0x04
65#define MAX6650_REG_DAC 0x06
66#define MAX6650_REG_ALARM_EN 0x08
67#define MAX6650_REG_ALARM 0x0A
68#define MAX6650_REG_TACH0 0x0C
69#define MAX6650_REG_TACH1 0x0E
70#define MAX6650_REG_TACH2 0x10
71#define MAX6650_REG_TACH3 0x12
72#define MAX6650_REG_GPIO_STAT 0x14
73#define MAX6650_REG_COUNT 0x16
74
75/*
76 * Config register bits
77 */
78
79#define MAX6650_CFG_V12 0x08
80#define MAX6650_CFG_PRESCALER_MASK 0x07
81#define MAX6650_CFG_PRESCALER_2 0x01
82#define MAX6650_CFG_PRESCALER_4 0x02
83#define MAX6650_CFG_PRESCALER_8 0x03
84#define MAX6650_CFG_PRESCALER_16 0x04
85#define MAX6650_CFG_MODE_MASK 0x30
86#define MAX6650_CFG_MODE_ON 0x00
87#define MAX6650_CFG_MODE_OFF 0x10
88#define MAX6650_CFG_MODE_CLOSED_LOOP 0x20
89#define MAX6650_CFG_MODE_OPEN_LOOP 0x30
90#define MAX6650_COUNT_MASK 0x03
91
92/*
93 * Alarm status register bits
94 */
95
96#define MAX6650_ALRM_MAX 0x01
97#define MAX6650_ALRM_MIN 0x02
98#define MAX6650_ALRM_TACH 0x04
99#define MAX6650_ALRM_GPIO1 0x08
100#define MAX6650_ALRM_GPIO2 0x10
101
102/* Minimum and maximum values of the FAN-RPM */
103#define FAN_RPM_MIN 240
104#define FAN_RPM_MAX 30000
105
106#define DIV_FROM_REG(reg) (1 << (reg & 7))
107
108static int max6650_probe(struct i2c_client *client,
109 const struct i2c_device_id *id);
110static int max6650_init_client(struct i2c_client *client);
111static int max6650_remove(struct i2c_client *client);
112static struct max6650_data *max6650_update_device(struct device *dev);
113
114/*
115 * Driver data (common to all clients)
116 */
117
118static const struct i2c_device_id max6650_id[] = {
119 { "max6650", 1 },
120 { "max6651", 4 },
121 { }
122};
123MODULE_DEVICE_TABLE(i2c, max6650_id);
124
125static struct i2c_driver max6650_driver = {
126 .driver = {
127 .name = "max6650",
128 },
129 .probe = max6650_probe,
130 .remove = max6650_remove,
131 .id_table = max6650_id,
132};
133
134/*
135 * Client data (each client gets its own)
136 */
137
138struct max6650_data
139{
140 struct device *hwmon_dev;
141 struct mutex update_lock;
142 int nr_fans;
143 char valid; /* zero until following fields are valid */
144 unsigned long last_updated; /* in jiffies */
145
146 /* register values */
147 u8 speed;
148 u8 config;
149 u8 tach[4];
150 u8 count;
151 u8 dac;
152 u8 alarm;
153};
154
155static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
156 char *buf)
157{
158 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
159 struct max6650_data *data = max6650_update_device(dev);
160 int rpm;
161
162 /*
163 * Calculation details:
164 *
165 * Each tachometer counts over an interval given by the "count"
166 * register (0.25, 0.5, 1 or 2 seconds). This module assumes
167 * that the fans produce two pulses per revolution (this seems
168 * to be the most common).
169 */
170
171 rpm = ((data->tach[attr->index] * 120) / DIV_FROM_REG(data->count));
172 return sprintf(buf, "%d\n", rpm);
173}
174
175/*
176 * Set the fan speed to the specified RPM (or read back the RPM setting).
177 * This works in closed loop mode only. Use pwm1 for open loop speed setting.
178 *
179 * The MAX6650/1 will automatically control fan speed when in closed loop
180 * mode.
181 *
182 * Assumptions:
183 *
184 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use
185 * the clock module parameter if you need to fine tune this.
186 *
187 * 2) The prescaler (low three bits of the config register) has already
188 * been set to an appropriate value. Use the prescaler module parameter
189 * if your BIOS doesn't initialize the chip properly.
190 *
191 * The relevant equations are given on pages 21 and 22 of the datasheet.
192 *
193 * From the datasheet, the relevant equation when in regulation is:
194 *
195 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE
196 *
197 * where:
198 *
199 * fCLK is the oscillator frequency (either the 254kHz internal
200 * oscillator or the externally applied clock)
201 *
202 * KTACH is the value in the speed register
203 *
204 * FanSpeed is the speed of the fan in rps
205 *
206 * KSCALE is the prescaler value (1, 2, 4, 8, or 16)
207 *
208 * When reading, we need to solve for FanSpeed. When writing, we need to
209 * solve for KTACH.
210 *
211 * Note: this tachometer is completely separate from the tachometers
212 * used to measure the fan speeds. Only one fan's speed (fan1) is
213 * controlled.
214 */
215
216static ssize_t get_target(struct device *dev, struct device_attribute *devattr,
217 char *buf)
218{
219 struct max6650_data *data = max6650_update_device(dev);
220 int kscale, ktach, rpm;
221
222 /*
223 * Use the datasheet equation:
224 *
225 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)]
226 *
227 * then multiply by 60 to give rpm.
228 */
229
230 kscale = DIV_FROM_REG(data->config);
231 ktach = data->speed;
232 rpm = 60 * kscale * clock / (256 * (ktach + 1));
233 return sprintf(buf, "%d\n", rpm);
234}
235
236static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
237 const char *buf, size_t count)
238{
239 struct i2c_client *client = to_i2c_client(dev);
240 struct max6650_data *data = i2c_get_clientdata(client);
241 int rpm = simple_strtoul(buf, NULL, 10);
242 int kscale, ktach;
243
244 rpm = SENSORS_LIMIT(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
245
246 /*
247 * Divide the required speed by 60 to get from rpm to rps, then
248 * use the datasheet equation:
249 *
250 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
251 */
252
253 mutex_lock(&data->update_lock);
254
255 kscale = DIV_FROM_REG(data->config);
256 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
257 if (ktach < 0)
258 ktach = 0;
259 if (ktach > 255)
260 ktach = 255;
261 data->speed = ktach;
262
263 i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed);
264
265 mutex_unlock(&data->update_lock);
266
267 return count;
268}
269
270/*
271 * Get/set the fan speed in open loop mode using pwm1 sysfs file.
272 * Speed is given as a relative value from 0 to 255, where 255 is maximum
273 * speed. Note that this is done by writing directly to the chip's DAC,
274 * it won't change the closed loop speed set by fan1_target.
275 * Also note that due to rounding errors it is possible that you don't read
276 * back exactly the value you have set.
277 */
278
279static ssize_t get_pwm(struct device *dev, struct device_attribute *devattr,
280 char *buf)
281{
282 int pwm;
283 struct max6650_data *data = max6650_update_device(dev);
284
285 /* Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
286 Lower DAC values mean higher speeds. */
287 if (data->config & MAX6650_CFG_V12)
288 pwm = 255 - (255 * (int)data->dac)/180;
289 else
290 pwm = 255 - (255 * (int)data->dac)/76;
291
292 if (pwm < 0)
293 pwm = 0;
294
295 return sprintf(buf, "%d\n", pwm);
296}
297
298static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
299 const char *buf, size_t count)
300{
301 struct i2c_client *client = to_i2c_client(dev);
302 struct max6650_data *data = i2c_get_clientdata(client);
303 int pwm = simple_strtoul(buf, NULL, 10);
304
305 pwm = SENSORS_LIMIT(pwm, 0, 255);
306
307 mutex_lock(&data->update_lock);
308
309 if (data->config & MAX6650_CFG_V12)
310 data->dac = 180 - (180 * pwm)/255;
311 else
312 data->dac = 76 - (76 * pwm)/255;
313
314 i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
315
316 mutex_unlock(&data->update_lock);
317
318 return count;
319}
320
321/*
322 * Get/Set controller mode:
323 * Possible values:
324 * 0 = Fan always on
325 * 1 = Open loop, Voltage is set according to speed, not regulated.
326 * 2 = Closed loop, RPM for all fans regulated by fan1 tachometer
327 */
328
329static ssize_t get_enable(struct device *dev, struct device_attribute *devattr,
330 char *buf)
331{
332 struct max6650_data *data = max6650_update_device(dev);
333 int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
334 int sysfs_modes[4] = {0, 1, 2, 1};
335
336 return sprintf(buf, "%d\n", sysfs_modes[mode]);
337}
338
339static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,
340 const char *buf, size_t count)
341{
342 struct i2c_client *client = to_i2c_client(dev);
343 struct max6650_data *data = i2c_get_clientdata(client);
344 int mode = simple_strtoul(buf, NULL, 10);
345 int max6650_modes[3] = {0, 3, 2};
346
347 if ((mode < 0)||(mode > 2)) {
348 dev_err(&client->dev,
349 "illegal value for pwm1_enable (%d)\n", mode);
350 return -EINVAL;
351 }
352
353 mutex_lock(&data->update_lock);
354
355 data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
356 data->config = (data->config & ~MAX6650_CFG_MODE_MASK)
357 | (max6650_modes[mode] << 4);
358
359 i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config);
360
361 mutex_unlock(&data->update_lock);
362
363 return count;
364}
365
366/*
367 * Read/write functions for fan1_div sysfs file. The MAX6650 has no such
368 * divider. We handle this by converting between divider and counttime:
369 *
370 * (counttime == k) <==> (divider == 2^k), k = 0, 1, 2, or 3
371 *
372 * Lower values of k allow to connect a faster fan without the risk of
373 * counter overflow. The price is lower resolution. You can also set counttime
374 * using the module parameter. Note that the module parameter "prescaler" also
375 * influences the behaviour. Unfortunately, there's no sysfs attribute
376 * defined for that. See the data sheet for details.
377 */
378
379static ssize_t get_div(struct device *dev, struct device_attribute *devattr,
380 char *buf)
381{
382 struct max6650_data *data = max6650_update_device(dev);
383
384 return sprintf(buf, "%d\n", DIV_FROM_REG(data->count));
385}
386
387static ssize_t set_div(struct device *dev, struct device_attribute *devattr,
388 const char *buf, size_t count)
389{
390 struct i2c_client *client = to_i2c_client(dev);
391 struct max6650_data *data = i2c_get_clientdata(client);
392 int div = simple_strtoul(buf, NULL, 10);
393
394 mutex_lock(&data->update_lock);
395 switch (div) {
396 case 1:
397 data->count = 0;
398 break;
399 case 2:
400 data->count = 1;
401 break;
402 case 4:
403 data->count = 2;
404 break;
405 case 8:
406 data->count = 3;
407 break;
408 default:
409 mutex_unlock(&data->update_lock);
410 dev_err(&client->dev,
411 "illegal value for fan divider (%d)\n", div);
412 return -EINVAL;
413 }
414
415 i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count);
416 mutex_unlock(&data->update_lock);
417
418 return count;
419}
420
421/*
422 * Get alarm stati:
423 * Possible values:
424 * 0 = no alarm
425 * 1 = alarm
426 */
427
428static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr,
429 char *buf)
430{
431 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
432 struct max6650_data *data = max6650_update_device(dev);
433 struct i2c_client *client = to_i2c_client(dev);
434 int alarm = 0;
435
436 if (data->alarm & attr->index) {
437 mutex_lock(&data->update_lock);
438 alarm = 1;
439 data->alarm &= ~attr->index;
440 data->alarm |= i2c_smbus_read_byte_data(client,
441 MAX6650_REG_ALARM);
442 mutex_unlock(&data->update_lock);
443 }
444
445 return sprintf(buf, "%d\n", alarm);
446}
447
448static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0);
449static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1);
450static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2);
451static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, get_fan, NULL, 3);
452static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, get_target, set_target);
453static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div);
454static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable);
455static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
456static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, get_alarm, NULL,
457 MAX6650_ALRM_MAX);
458static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, get_alarm, NULL,
459 MAX6650_ALRM_MIN);
460static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_alarm, NULL,
461 MAX6650_ALRM_TACH);
462static SENSOR_DEVICE_ATTR(gpio1_alarm, S_IRUGO, get_alarm, NULL,
463 MAX6650_ALRM_GPIO1);
464static SENSOR_DEVICE_ATTR(gpio2_alarm, S_IRUGO, get_alarm, NULL,
465 MAX6650_ALRM_GPIO2);
466
467static mode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
468 int n)
469{
470 struct device *dev = container_of(kobj, struct device, kobj);
471 struct i2c_client *client = to_i2c_client(dev);
472 u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
473 struct device_attribute *devattr;
474
475 /*
476 * Hide the alarms that have not been enabled by the firmware
477 */
478
479 devattr = container_of(a, struct device_attribute, attr);
480 if (devattr == &sensor_dev_attr_fan1_max_alarm.dev_attr
481 || devattr == &sensor_dev_attr_fan1_min_alarm.dev_attr
482 || devattr == &sensor_dev_attr_fan1_fault.dev_attr
483 || devattr == &sensor_dev_attr_gpio1_alarm.dev_attr
484 || devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
485 if (!(alarm_en & to_sensor_dev_attr(devattr)->index))
486 return 0;
487 }
488
489 return a->mode;
490}
491
492static struct attribute *max6650_attrs[] = {
493 &sensor_dev_attr_fan1_input.dev_attr.attr,
494 &dev_attr_fan1_target.attr,
495 &dev_attr_fan1_div.attr,
496 &dev_attr_pwm1_enable.attr,
497 &dev_attr_pwm1.attr,
498 &sensor_dev_attr_fan1_max_alarm.dev_attr.attr,
499 &sensor_dev_attr_fan1_min_alarm.dev_attr.attr,
500 &sensor_dev_attr_fan1_fault.dev_attr.attr,
501 &sensor_dev_attr_gpio1_alarm.dev_attr.attr,
502 &sensor_dev_attr_gpio2_alarm.dev_attr.attr,
503 NULL
504};
505
506static struct attribute_group max6650_attr_grp = {
507 .attrs = max6650_attrs,
508 .is_visible = max6650_attrs_visible,
509};
510
511static struct attribute *max6651_attrs[] = {
512 &sensor_dev_attr_fan2_input.dev_attr.attr,
513 &sensor_dev_attr_fan3_input.dev_attr.attr,
514 &sensor_dev_attr_fan4_input.dev_attr.attr,
515 NULL
516};
517
518static const struct attribute_group max6651_attr_grp = {
519 .attrs = max6651_attrs,
520};
521
522/*
523 * Real code
524 */
525
526static int max6650_probe(struct i2c_client *client,
527 const struct i2c_device_id *id)
528{
529 struct max6650_data *data;
530 int err;
531
532 if (!(data = kzalloc(sizeof(struct max6650_data), GFP_KERNEL))) {
533 dev_err(&client->dev, "out of memory.\n");
534 return -ENOMEM;
535 }
536
537 i2c_set_clientdata(client, data);
538 mutex_init(&data->update_lock);
539 data->nr_fans = id->driver_data;
540
541 /*
542 * Initialize the max6650 chip
543 */
544 err = max6650_init_client(client);
545 if (err)
546 goto err_free;
547
548 err = sysfs_create_group(&client->dev.kobj, &max6650_attr_grp);
549 if (err)
550 goto err_free;
551 /* 3 additional fan inputs for the MAX6651 */
552 if (data->nr_fans == 4) {
553 err = sysfs_create_group(&client->dev.kobj, &max6651_attr_grp);
554 if (err)
555 goto err_remove;
556 }
557
558 data->hwmon_dev = hwmon_device_register(&client->dev);
559 if (!IS_ERR(data->hwmon_dev))
560 return 0;
561
562 err = PTR_ERR(data->hwmon_dev);
563 dev_err(&client->dev, "error registering hwmon device.\n");
564 if (data->nr_fans == 4)
565 sysfs_remove_group(&client->dev.kobj, &max6651_attr_grp);
566err_remove:
567 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
568err_free:
569 kfree(data);
570 return err;
571}
572
573static int max6650_remove(struct i2c_client *client)
574{
575 struct max6650_data *data = i2c_get_clientdata(client);
576
577 hwmon_device_unregister(data->hwmon_dev);
578 if (data->nr_fans == 4)
579 sysfs_remove_group(&client->dev.kobj, &max6651_attr_grp);
580 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
581 kfree(data);
582 return 0;
583}
584
585static int max6650_init_client(struct i2c_client *client)
586{
587 struct max6650_data *data = i2c_get_clientdata(client);
588 int config;
589 int err = -EIO;
590
591 config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
592
593 if (config < 0) {
594 dev_err(&client->dev, "Error reading config, aborting.\n");
595 return err;
596 }
597
598 switch (fan_voltage) {
599 case 0:
600 break;
601 case 5:
602 config &= ~MAX6650_CFG_V12;
603 break;
604 case 12:
605 config |= MAX6650_CFG_V12;
606 break;
607 default:
608 dev_err(&client->dev,
609 "illegal value for fan_voltage (%d)\n",
610 fan_voltage);
611 }
612
613 dev_info(&client->dev, "Fan voltage is set to %dV.\n",
614 (config & MAX6650_CFG_V12) ? 12 : 5);
615
616 switch (prescaler) {
617 case 0:
618 break;
619 case 1:
620 config &= ~MAX6650_CFG_PRESCALER_MASK;
621 break;
622 case 2:
623 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
624 | MAX6650_CFG_PRESCALER_2;
625 break;
626 case 4:
627 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
628 | MAX6650_CFG_PRESCALER_4;
629 break;
630 case 8:
631 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
632 | MAX6650_CFG_PRESCALER_8;
633 break;
634 case 16:
635 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
636 | MAX6650_CFG_PRESCALER_16;
637 break;
638 default:
639 dev_err(&client->dev,
640 "illegal value for prescaler (%d)\n",
641 prescaler);
642 }
643
644 dev_info(&client->dev, "Prescaler is set to %d.\n",
645 1 << (config & MAX6650_CFG_PRESCALER_MASK));
646
647 /* If mode is set to "full off", we change it to "open loop" and
648 * set DAC to 255, which has the same effect. We do this because
649 * there's no "full off" mode defined in hwmon specifcations.
650 */
651
652 if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) {
653 dev_dbg(&client->dev, "Change mode to open loop, full off.\n");
654 config = (config & ~MAX6650_CFG_MODE_MASK)
655 | MAX6650_CFG_MODE_OPEN_LOOP;
656 if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) {
657 dev_err(&client->dev, "DAC write error, aborting.\n");
658 return err;
659 }
660 }
661
662 if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) {
663 dev_err(&client->dev, "Config write error, aborting.\n");
664 return err;
665 }
666
667 data->config = config;
668 data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
669
670 return 0;
671}
672
673static const u8 tach_reg[] = {
674 MAX6650_REG_TACH0,
675 MAX6650_REG_TACH1,
676 MAX6650_REG_TACH2,
677 MAX6650_REG_TACH3,
678};
679
680static struct max6650_data *max6650_update_device(struct device *dev)
681{
682 int i;
683 struct i2c_client *client = to_i2c_client(dev);
684 struct max6650_data *data = i2c_get_clientdata(client);
685
686 mutex_lock(&data->update_lock);
687
688 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
689 data->speed = i2c_smbus_read_byte_data(client,
690 MAX6650_REG_SPEED);
691 data->config = i2c_smbus_read_byte_data(client,
692 MAX6650_REG_CONFIG);
693 for (i = 0; i < data->nr_fans; i++) {
694 data->tach[i] = i2c_smbus_read_byte_data(client,
695 tach_reg[i]);
696 }
697 data->count = i2c_smbus_read_byte_data(client,
698 MAX6650_REG_COUNT);
699 data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
700
701 /* Alarms are cleared on read in case the condition that
702 * caused the alarm is removed. Keep the value latched here
703 * for providing the register through different alarm files. */
704 data->alarm |= i2c_smbus_read_byte_data(client,
705 MAX6650_REG_ALARM);
706
707 data->last_updated = jiffies;
708 data->valid = 1;
709 }
710
711 mutex_unlock(&data->update_lock);
712
713 return data;
714}
715
716static int __init sensors_max6650_init(void)
717{
718 return i2c_add_driver(&max6650_driver);
719}
720
721static void __exit sensors_max6650_exit(void)
722{
723 i2c_del_driver(&max6650_driver);
724}
725
726MODULE_AUTHOR("Hans J. Koch");
727MODULE_DESCRIPTION("MAX6650 sensor driver");
728MODULE_LICENSE("GPL");
729
730module_init(sensors_max6650_init);
731module_exit(sensors_max6650_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware
4 * monitoring.
5 *
6 * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de>
7 *
8 * based on code written by John Morris <john.morris@spirentcom.com>
9 * Copyright (c) 2003 Spirent Communications
10 * and Claus Gindhart <claus.gindhart@kontron.com>
11 *
12 * This module has only been tested with the MAX6650 chip. It should
13 * also work with the MAX6651. It does not distinguish max6650 and max6651
14 * chips.
15 *
16 * The datasheet was last seen at:
17 *
18 * http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
19 */
20
21#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/slab.h>
24#include <linux/jiffies.h>
25#include <linux/i2c.h>
26#include <linux/hwmon.h>
27#include <linux/hwmon-sysfs.h>
28#include <linux/err.h>
29#include <linux/of_device.h>
30#include <linux/thermal.h>
31
32/*
33 * Insmod parameters
34 */
35
36/* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
37static int fan_voltage;
38/* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
39static int prescaler;
40/* clock: The clock frequency of the chip (max6651 can be clocked externally) */
41static int clock = 254000;
42
43module_param(fan_voltage, int, 0444);
44module_param(prescaler, int, 0444);
45module_param(clock, int, 0444);
46
47/*
48 * MAX 6650/6651 registers
49 */
50
51#define MAX6650_REG_SPEED 0x00
52#define MAX6650_REG_CONFIG 0x02
53#define MAX6650_REG_GPIO_DEF 0x04
54#define MAX6650_REG_DAC 0x06
55#define MAX6650_REG_ALARM_EN 0x08
56#define MAX6650_REG_ALARM 0x0A
57#define MAX6650_REG_TACH0 0x0C
58#define MAX6650_REG_TACH1 0x0E
59#define MAX6650_REG_TACH2 0x10
60#define MAX6650_REG_TACH3 0x12
61#define MAX6650_REG_GPIO_STAT 0x14
62#define MAX6650_REG_COUNT 0x16
63
64/*
65 * Config register bits
66 */
67
68#define MAX6650_CFG_V12 0x08
69#define MAX6650_CFG_PRESCALER_MASK 0x07
70#define MAX6650_CFG_PRESCALER_2 0x01
71#define MAX6650_CFG_PRESCALER_4 0x02
72#define MAX6650_CFG_PRESCALER_8 0x03
73#define MAX6650_CFG_PRESCALER_16 0x04
74#define MAX6650_CFG_MODE_MASK 0x30
75#define MAX6650_CFG_MODE_ON 0x00
76#define MAX6650_CFG_MODE_OFF 0x10
77#define MAX6650_CFG_MODE_CLOSED_LOOP 0x20
78#define MAX6650_CFG_MODE_OPEN_LOOP 0x30
79#define MAX6650_COUNT_MASK 0x03
80
81/*
82 * Alarm status register bits
83 */
84
85#define MAX6650_ALRM_MAX 0x01
86#define MAX6650_ALRM_MIN 0x02
87#define MAX6650_ALRM_TACH 0x04
88#define MAX6650_ALRM_GPIO1 0x08
89#define MAX6650_ALRM_GPIO2 0x10
90
91/* Minimum and maximum values of the FAN-RPM */
92#define FAN_RPM_MIN 240
93#define FAN_RPM_MAX 30000
94
95#define DIV_FROM_REG(reg) (1 << ((reg) & 7))
96#define DAC_LIMIT(v12) ((v12) ? 180 : 76)
97
98/*
99 * Client data (each client gets its own)
100 */
101
102struct max6650_data {
103 struct i2c_client *client;
104 struct mutex update_lock; /* protect alarm register updates */
105 int nr_fans;
106 bool valid; /* false until following fields are valid */
107 unsigned long last_updated; /* in jiffies */
108
109 /* register values */
110 u8 speed;
111 u8 config;
112 u8 tach[4];
113 u8 count;
114 u8 dac;
115 u8 alarm;
116 u8 alarm_en;
117 unsigned long cooling_dev_state;
118};
119
120static const u8 tach_reg[] = {
121 MAX6650_REG_TACH0,
122 MAX6650_REG_TACH1,
123 MAX6650_REG_TACH2,
124 MAX6650_REG_TACH3,
125};
126
127static const struct of_device_id __maybe_unused max6650_dt_match[] = {
128 {
129 .compatible = "maxim,max6650",
130 .data = (void *)1
131 },
132 {
133 .compatible = "maxim,max6651",
134 .data = (void *)4
135 },
136 { },
137};
138MODULE_DEVICE_TABLE(of, max6650_dt_match);
139
140static int dac_to_pwm(int dac, bool v12)
141{
142 /*
143 * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
144 * Lower DAC values mean higher speeds.
145 */
146 return clamp_val(255 - (255 * dac) / DAC_LIMIT(v12), 0, 255);
147}
148
149static u8 pwm_to_dac(unsigned int pwm, bool v12)
150{
151 int limit = DAC_LIMIT(v12);
152
153 return limit - (limit * pwm) / 255;
154}
155
156static struct max6650_data *max6650_update_device(struct device *dev)
157{
158 struct max6650_data *data = dev_get_drvdata(dev);
159 struct i2c_client *client = data->client;
160 int reg, err = 0;
161 int i;
162
163 mutex_lock(&data->update_lock);
164
165 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
166 for (i = 0; i < data->nr_fans; i++) {
167 reg = i2c_smbus_read_byte_data(client, tach_reg[i]);
168 if (reg < 0) {
169 err = reg;
170 goto error;
171 }
172 data->tach[i] = reg;
173 }
174
175 /*
176 * Alarms are cleared on read in case the condition that
177 * caused the alarm is removed. Keep the value latched here
178 * for providing the register through different alarm files.
179 */
180 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM);
181 if (reg < 0) {
182 err = reg;
183 goto error;
184 }
185 data->alarm |= reg;
186 data->last_updated = jiffies;
187 data->valid = true;
188 }
189
190error:
191 mutex_unlock(&data->update_lock);
192 if (err)
193 data = ERR_PTR(err);
194 return data;
195}
196
197/*
198 * Change the operating mode of the chip (if needed).
199 * mode is one of the MAX6650_CFG_MODE_* values.
200 */
201static int max6650_set_operating_mode(struct max6650_data *data, u8 mode)
202{
203 int result;
204 u8 config = data->config;
205
206 if (mode == (config & MAX6650_CFG_MODE_MASK))
207 return 0;
208
209 config = (config & ~MAX6650_CFG_MODE_MASK) | mode;
210
211 result = i2c_smbus_write_byte_data(data->client, MAX6650_REG_CONFIG,
212 config);
213 if (result < 0)
214 return result;
215
216 data->config = config;
217
218 return 0;
219}
220
221/*
222 * Set the fan speed to the specified RPM (or read back the RPM setting).
223 * This works in closed loop mode only. Use pwm1 for open loop speed setting.
224 *
225 * The MAX6650/1 will automatically control fan speed when in closed loop
226 * mode.
227 *
228 * Assumptions:
229 *
230 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use
231 * the clock module parameter if you need to fine tune this.
232 *
233 * 2) The prescaler (low three bits of the config register) has already
234 * been set to an appropriate value. Use the prescaler module parameter
235 * if your BIOS doesn't initialize the chip properly.
236 *
237 * The relevant equations are given on pages 21 and 22 of the datasheet.
238 *
239 * From the datasheet, the relevant equation when in regulation is:
240 *
241 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE
242 *
243 * where:
244 *
245 * fCLK is the oscillator frequency (either the 254kHz internal
246 * oscillator or the externally applied clock)
247 *
248 * KTACH is the value in the speed register
249 *
250 * FanSpeed is the speed of the fan in rps
251 *
252 * KSCALE is the prescaler value (1, 2, 4, 8, or 16)
253 *
254 * When reading, we need to solve for FanSpeed. When writing, we need to
255 * solve for KTACH.
256 *
257 * Note: this tachometer is completely separate from the tachometers
258 * used to measure the fan speeds. Only one fan's speed (fan1) is
259 * controlled.
260 */
261
262static int max6650_set_target(struct max6650_data *data, unsigned long rpm)
263{
264 int kscale, ktach;
265
266 if (rpm == 0)
267 return max6650_set_operating_mode(data, MAX6650_CFG_MODE_OFF);
268
269 rpm = clamp_val(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
270
271 /*
272 * Divide the required speed by 60 to get from rpm to rps, then
273 * use the datasheet equation:
274 *
275 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
276 */
277
278 kscale = DIV_FROM_REG(data->config);
279 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
280 if (ktach < 0)
281 ktach = 0;
282 if (ktach > 255)
283 ktach = 255;
284 data->speed = ktach;
285
286 return i2c_smbus_write_byte_data(data->client, MAX6650_REG_SPEED,
287 data->speed);
288}
289
290/*
291 * Get gpio alarm status:
292 * Possible values:
293 * 0 = no alarm
294 * 1 = alarm
295 */
296
297static ssize_t alarm_show(struct device *dev,
298 struct device_attribute *devattr, char *buf)
299{
300 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
301 struct max6650_data *data = max6650_update_device(dev);
302 bool alarm;
303
304 if (IS_ERR(data))
305 return PTR_ERR(data);
306
307 alarm = data->alarm & attr->index;
308 if (alarm) {
309 mutex_lock(&data->update_lock);
310 data->alarm &= ~attr->index;
311 data->valid = false;
312 mutex_unlock(&data->update_lock);
313 }
314
315 return sprintf(buf, "%d\n", alarm);
316}
317
318static SENSOR_DEVICE_ATTR_RO(gpio1_alarm, alarm, MAX6650_ALRM_GPIO1);
319static SENSOR_DEVICE_ATTR_RO(gpio2_alarm, alarm, MAX6650_ALRM_GPIO2);
320
321static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
322 int n)
323{
324 struct device *dev = kobj_to_dev(kobj);
325 struct max6650_data *data = dev_get_drvdata(dev);
326 struct device_attribute *devattr;
327
328 /*
329 * Hide the alarms that have not been enabled by the firmware
330 */
331
332 devattr = container_of(a, struct device_attribute, attr);
333 if (devattr == &sensor_dev_attr_gpio1_alarm.dev_attr ||
334 devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
335 if (!(data->alarm_en & to_sensor_dev_attr(devattr)->index))
336 return 0;
337 }
338
339 return a->mode;
340}
341
342static struct attribute *max6650_attrs[] = {
343 &sensor_dev_attr_gpio1_alarm.dev_attr.attr,
344 &sensor_dev_attr_gpio2_alarm.dev_attr.attr,
345 NULL
346};
347
348static const struct attribute_group max6650_group = {
349 .attrs = max6650_attrs,
350 .is_visible = max6650_attrs_visible,
351};
352
353static const struct attribute_group *max6650_groups[] = {
354 &max6650_group,
355 NULL
356};
357
358static int max6650_init_client(struct max6650_data *data,
359 struct i2c_client *client)
360{
361 struct device *dev = &client->dev;
362 int reg;
363 int err;
364 u32 voltage;
365 u32 prescale;
366 u32 target_rpm;
367
368 if (of_property_read_u32(dev->of_node, "maxim,fan-microvolt",
369 &voltage))
370 voltage = fan_voltage;
371 else
372 voltage /= 1000000; /* Microvolts to volts */
373 if (of_property_read_u32(dev->of_node, "maxim,fan-prescale",
374 &prescale))
375 prescale = prescaler;
376
377 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
378 if (reg < 0) {
379 dev_err(dev, "Error reading config register, aborting.\n");
380 return reg;
381 }
382
383 switch (voltage) {
384 case 0:
385 break;
386 case 5:
387 reg &= ~MAX6650_CFG_V12;
388 break;
389 case 12:
390 reg |= MAX6650_CFG_V12;
391 break;
392 default:
393 dev_err(dev, "illegal value for fan_voltage (%d)\n", voltage);
394 }
395
396 switch (prescale) {
397 case 0:
398 break;
399 case 1:
400 reg &= ~MAX6650_CFG_PRESCALER_MASK;
401 break;
402 case 2:
403 reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
404 | MAX6650_CFG_PRESCALER_2;
405 break;
406 case 4:
407 reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
408 | MAX6650_CFG_PRESCALER_4;
409 break;
410 case 8:
411 reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
412 | MAX6650_CFG_PRESCALER_8;
413 break;
414 case 16:
415 reg = (reg & ~MAX6650_CFG_PRESCALER_MASK)
416 | MAX6650_CFG_PRESCALER_16;
417 break;
418 default:
419 dev_err(dev, "illegal value for prescaler (%d)\n", prescale);
420 }
421
422 dev_info(dev, "Fan voltage: %dV, prescaler: %d.\n",
423 (reg & MAX6650_CFG_V12) ? 12 : 5,
424 1 << (reg & MAX6650_CFG_PRESCALER_MASK));
425
426 err = i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, reg);
427 if (err) {
428 dev_err(dev, "Config write error, aborting.\n");
429 return err;
430 }
431 data->config = reg;
432
433 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_SPEED);
434 if (reg < 0) {
435 dev_err(dev, "Failed to read speed register, aborting.\n");
436 return reg;
437 }
438 data->speed = reg;
439
440 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
441 if (reg < 0) {
442 dev_err(dev, "Failed to read DAC register, aborting.\n");
443 return reg;
444 }
445 data->dac = reg;
446
447 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
448 if (reg < 0) {
449 dev_err(dev, "Failed to read count register, aborting.\n");
450 return reg;
451 }
452 data->count = reg;
453
454 reg = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
455 if (reg < 0) {
456 dev_err(dev, "Failed to read alarm configuration, aborting.\n");
457 return reg;
458 }
459 data->alarm_en = reg;
460
461 if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm",
462 &target_rpm)) {
463 max6650_set_target(data, target_rpm);
464 max6650_set_operating_mode(data, MAX6650_CFG_MODE_CLOSED_LOOP);
465 }
466
467 return 0;
468}
469
470static int max6650_get_max_state(struct thermal_cooling_device *cdev,
471 unsigned long *state)
472{
473 *state = 255;
474
475 return 0;
476}
477
478static int max6650_get_cur_state(struct thermal_cooling_device *cdev,
479 unsigned long *state)
480{
481 struct max6650_data *data = cdev->devdata;
482
483 *state = data->cooling_dev_state;
484
485 return 0;
486}
487
488static int max6650_set_cur_state(struct thermal_cooling_device *cdev,
489 unsigned long state)
490{
491 struct max6650_data *data = cdev->devdata;
492 struct i2c_client *client = data->client;
493 int err;
494
495 state = clamp_val(state, 0, 255);
496
497 mutex_lock(&data->update_lock);
498
499 data->dac = pwm_to_dac(state, data->config & MAX6650_CFG_V12);
500 err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
501 if (!err) {
502 max6650_set_operating_mode(data, state ?
503 MAX6650_CFG_MODE_OPEN_LOOP :
504 MAX6650_CFG_MODE_OFF);
505 data->cooling_dev_state = state;
506 }
507
508 mutex_unlock(&data->update_lock);
509
510 return err;
511}
512
513static const struct thermal_cooling_device_ops max6650_cooling_ops = {
514 .get_max_state = max6650_get_max_state,
515 .get_cur_state = max6650_get_cur_state,
516 .set_cur_state = max6650_set_cur_state,
517};
518
519static int max6650_read(struct device *dev, enum hwmon_sensor_types type,
520 u32 attr, int channel, long *val)
521{
522 struct max6650_data *data = max6650_update_device(dev);
523 int mode;
524
525 if (IS_ERR(data))
526 return PTR_ERR(data);
527
528 switch (type) {
529 case hwmon_pwm:
530 switch (attr) {
531 case hwmon_pwm_input:
532 *val = dac_to_pwm(data->dac,
533 data->config & MAX6650_CFG_V12);
534 break;
535 case hwmon_pwm_enable:
536 /*
537 * Possible values:
538 * 0 = Fan always on
539 * 1 = Open loop, Voltage is set according to speed,
540 * not regulated.
541 * 2 = Closed loop, RPM for all fans regulated by fan1
542 * tachometer
543 * 3 = Fan off
544 */
545 mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
546 *val = (4 - mode) & 3; /* {0 1 2 3} -> {0 3 2 1} */
547 break;
548 default:
549 return -EOPNOTSUPP;
550 }
551 break;
552 case hwmon_fan:
553 switch (attr) {
554 case hwmon_fan_input:
555 /*
556 * Calculation details:
557 *
558 * Each tachometer counts over an interval given by the
559 * "count" register (0.25, 0.5, 1 or 2 seconds).
560 * The driver assumes that the fans produce two pulses
561 * per revolution (this seems to be the most common).
562 */
563 *val = DIV_ROUND_CLOSEST(data->tach[channel] * 120,
564 DIV_FROM_REG(data->count));
565 break;
566 case hwmon_fan_div:
567 *val = DIV_FROM_REG(data->count);
568 break;
569 case hwmon_fan_target:
570 /*
571 * Use the datasheet equation:
572 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)]
573 * then multiply by 60 to give rpm.
574 */
575 *val = 60 * DIV_FROM_REG(data->config) * clock /
576 (256 * (data->speed + 1));
577 break;
578 case hwmon_fan_min_alarm:
579 *val = !!(data->alarm & MAX6650_ALRM_MIN);
580 data->alarm &= ~MAX6650_ALRM_MIN;
581 data->valid = false;
582 break;
583 case hwmon_fan_max_alarm:
584 *val = !!(data->alarm & MAX6650_ALRM_MAX);
585 data->alarm &= ~MAX6650_ALRM_MAX;
586 data->valid = false;
587 break;
588 case hwmon_fan_fault:
589 *val = !!(data->alarm & MAX6650_ALRM_TACH);
590 data->alarm &= ~MAX6650_ALRM_TACH;
591 data->valid = false;
592 break;
593 default:
594 return -EOPNOTSUPP;
595 }
596 break;
597 default:
598 return -EOPNOTSUPP;
599 }
600 return 0;
601}
602
603static const u8 max6650_pwm_modes[] = {
604 MAX6650_CFG_MODE_ON,
605 MAX6650_CFG_MODE_OPEN_LOOP,
606 MAX6650_CFG_MODE_CLOSED_LOOP,
607 MAX6650_CFG_MODE_OFF,
608};
609
610static int max6650_write(struct device *dev, enum hwmon_sensor_types type,
611 u32 attr, int channel, long val)
612{
613 struct max6650_data *data = dev_get_drvdata(dev);
614 int ret = 0;
615 u8 reg;
616
617 mutex_lock(&data->update_lock);
618
619 switch (type) {
620 case hwmon_pwm:
621 switch (attr) {
622 case hwmon_pwm_input:
623 reg = pwm_to_dac(clamp_val(val, 0, 255),
624 data->config & MAX6650_CFG_V12);
625 ret = i2c_smbus_write_byte_data(data->client,
626 MAX6650_REG_DAC, reg);
627 if (ret)
628 break;
629 data->dac = reg;
630 break;
631 case hwmon_pwm_enable:
632 if (val < 0 || val >= ARRAY_SIZE(max6650_pwm_modes)) {
633 ret = -EINVAL;
634 break;
635 }
636 ret = max6650_set_operating_mode(data,
637 max6650_pwm_modes[val]);
638 break;
639 default:
640 ret = -EOPNOTSUPP;
641 break;
642 }
643 break;
644 case hwmon_fan:
645 switch (attr) {
646 case hwmon_fan_div:
647 switch (val) {
648 case 1:
649 reg = 0;
650 break;
651 case 2:
652 reg = 1;
653 break;
654 case 4:
655 reg = 2;
656 break;
657 case 8:
658 reg = 3;
659 break;
660 default:
661 ret = -EINVAL;
662 goto error;
663 }
664 ret = i2c_smbus_write_byte_data(data->client,
665 MAX6650_REG_COUNT, reg);
666 if (ret)
667 break;
668 data->count = reg;
669 break;
670 case hwmon_fan_target:
671 if (val < 0) {
672 ret = -EINVAL;
673 break;
674 }
675 ret = max6650_set_target(data, val);
676 break;
677 default:
678 ret = -EOPNOTSUPP;
679 break;
680 }
681 break;
682 default:
683 ret = -EOPNOTSUPP;
684 break;
685 }
686
687error:
688 mutex_unlock(&data->update_lock);
689 return ret;
690}
691
692static umode_t max6650_is_visible(const void *_data,
693 enum hwmon_sensor_types type, u32 attr,
694 int channel)
695{
696 const struct max6650_data *data = _data;
697
698 if (channel && (channel >= data->nr_fans || type != hwmon_fan))
699 return 0;
700
701 switch (type) {
702 case hwmon_fan:
703 switch (attr) {
704 case hwmon_fan_input:
705 return 0444;
706 case hwmon_fan_target:
707 case hwmon_fan_div:
708 return 0644;
709 case hwmon_fan_min_alarm:
710 if (data->alarm_en & MAX6650_ALRM_MIN)
711 return 0444;
712 break;
713 case hwmon_fan_max_alarm:
714 if (data->alarm_en & MAX6650_ALRM_MAX)
715 return 0444;
716 break;
717 case hwmon_fan_fault:
718 if (data->alarm_en & MAX6650_ALRM_TACH)
719 return 0444;
720 break;
721 default:
722 break;
723 }
724 break;
725 case hwmon_pwm:
726 switch (attr) {
727 case hwmon_pwm_input:
728 case hwmon_pwm_enable:
729 return 0644;
730 default:
731 break;
732 }
733 break;
734 default:
735 break;
736 }
737 return 0;
738}
739
740static const struct hwmon_channel_info *max6650_info[] = {
741 HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_DIV |
742 HWMON_F_MIN_ALARM | HWMON_F_MAX_ALARM |
743 HWMON_F_FAULT,
744 HWMON_F_INPUT, HWMON_F_INPUT, HWMON_F_INPUT),
745 HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
746 NULL
747};
748
749static const struct hwmon_ops max6650_hwmon_ops = {
750 .read = max6650_read,
751 .write = max6650_write,
752 .is_visible = max6650_is_visible,
753};
754
755static const struct hwmon_chip_info max6650_chip_info = {
756 .ops = &max6650_hwmon_ops,
757 .info = max6650_info,
758};
759
760static const struct i2c_device_id max6650_id[];
761
762static int max6650_probe(struct i2c_client *client)
763{
764 struct thermal_cooling_device *cooling_dev;
765 struct device *dev = &client->dev;
766 const struct of_device_id *of_id =
767 of_match_device(of_match_ptr(max6650_dt_match), dev);
768 struct max6650_data *data;
769 struct device *hwmon_dev;
770 int err;
771
772 data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL);
773 if (!data)
774 return -ENOMEM;
775
776 data->client = client;
777 i2c_set_clientdata(client, data);
778 mutex_init(&data->update_lock);
779 data->nr_fans = of_id ? (int)(uintptr_t)of_id->data :
780 i2c_match_id(max6650_id, client)->driver_data;
781
782 /*
783 * Initialize the max6650 chip
784 */
785 err = max6650_init_client(data, client);
786 if (err)
787 return err;
788
789 hwmon_dev = devm_hwmon_device_register_with_info(dev,
790 client->name, data,
791 &max6650_chip_info,
792 max6650_groups);
793 err = PTR_ERR_OR_ZERO(hwmon_dev);
794 if (err)
795 return err;
796
797 if (IS_ENABLED(CONFIG_THERMAL)) {
798 cooling_dev = devm_thermal_of_cooling_device_register(dev,
799 dev->of_node, client->name,
800 data, &max6650_cooling_ops);
801 if (IS_ERR(cooling_dev)) {
802 dev_warn(dev, "thermal cooling device register failed: %ld\n",
803 PTR_ERR(cooling_dev));
804 }
805 }
806
807 return 0;
808}
809
810static const struct i2c_device_id max6650_id[] = {
811 { "max6650", 1 },
812 { "max6651", 4 },
813 { }
814};
815MODULE_DEVICE_TABLE(i2c, max6650_id);
816
817static struct i2c_driver max6650_driver = {
818 .driver = {
819 .name = "max6650",
820 .of_match_table = of_match_ptr(max6650_dt_match),
821 },
822 .probe_new = max6650_probe,
823 .id_table = max6650_id,
824};
825
826module_i2c_driver(max6650_driver);
827
828MODULE_AUTHOR("Hans J. Koch");
829MODULE_DESCRIPTION("MAX6650 sensor driver");
830MODULE_LICENSE("GPL");