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Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-block.git] / drivers / hwmon / max6650.c
CommitLineData
d20620de
HJK		 1/*
2 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring.
4 *
2aa25c22 5 * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de>
d20620de
HJK		 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 *
52b5226f 15 * The datasheet was last seen at:
d20620de
HJK		 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>
a6cdeefe 42#include <linux/of_device.h>
d20620de 43
d20620de
HJK		 44/*
45 * Insmod parameters
46 */
47
48/* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
49static int fan_voltage;
50/* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
51static int prescaler;
a6cdeefe 52/* clock: The clock frequency of the chip (max6651 can be clocked externally) */
d20620de
HJK		 53static int clock = 254000;
54
55module_param(fan_voltage, int, S_IRUGO);
56module_param(prescaler, int, S_IRUGO);
57module_param(clock, int, S_IRUGO);
58
d20620de
HJK		 59/*
60 * MAX 6650/6651 registers
61 */
62
63#define MAX6650_REG_SPEED 0x00
64#define MAX6650_REG_CONFIG 0x02
65#define MAX6650_REG_GPIO_DEF 0x04
66#define MAX6650_REG_DAC 0x06
67#define MAX6650_REG_ALARM_EN 0x08
68#define MAX6650_REG_ALARM 0x0A
69#define MAX6650_REG_TACH0 0x0C
70#define MAX6650_REG_TACH1 0x0E
71#define MAX6650_REG_TACH2 0x10
72#define MAX6650_REG_TACH3 0x12
73#define MAX6650_REG_GPIO_STAT 0x14
74#define MAX6650_REG_COUNT 0x16
75
76/*
77 * Config register bits
78 */
79
80#define MAX6650_CFG_V12 0x08
81#define MAX6650_CFG_PRESCALER_MASK 0x07
82#define MAX6650_CFG_PRESCALER_2 0x01
83#define MAX6650_CFG_PRESCALER_4 0x02
84#define MAX6650_CFG_PRESCALER_8 0x03
85#define MAX6650_CFG_PRESCALER_16 0x04
86#define MAX6650_CFG_MODE_MASK 0x30
87#define MAX6650_CFG_MODE_ON 0x00
88#define MAX6650_CFG_MODE_OFF 0x10
89#define MAX6650_CFG_MODE_CLOSED_LOOP 0x20
90#define MAX6650_CFG_MODE_OPEN_LOOP 0x30
91#define MAX6650_COUNT_MASK 0x03
92
52b5226f
CE		 93/*
94 * Alarm status register bits
95 */
96
97#define MAX6650_ALRM_MAX 0x01
98#define MAX6650_ALRM_MIN 0x02
99#define MAX6650_ALRM_TACH 0x04
100#define MAX6650_ALRM_GPIO1 0x08
101#define MAX6650_ALRM_GPIO2 0x10
102
d20620de
HJK		 103/* Minimum and maximum values of the FAN-RPM */
104#define FAN_RPM_MIN 240
105#define FAN_RPM_MAX 30000
106
107#define DIV_FROM_REG(reg) (1 << (reg & 7))
108
d20620de
HJK		 109/*
110 * Client data (each client gets its own)
111 */
112
bafda5d0 113struct max6650_data {
17eaa25c
GR		 114 struct i2c_client *client;
115 const struct attribute_group *groups[3];
d20620de 116 struct mutex update_lock;
9c084dae 117 int nr_fans;
d20620de
HJK		 118 char valid; /* zero until following fields are valid */
119 unsigned long last_updated; /* in jiffies */
120
121 /* register values */
122 u8 speed;
123 u8 config;
124 u8 tach[4];
125 u8 count;
126 u8 dac;
52b5226f 127 u8 alarm;
d20620de
HJK		 128};
129
1577f94b
GR		 130static const u8 tach_reg[] = {
131 MAX6650_REG_TACH0,
132 MAX6650_REG_TACH1,
133 MAX6650_REG_TACH2,
134 MAX6650_REG_TACH3,
135};
136
a6cdeefe
ML		 137static const struct of_device_id max6650_dt_match[] = {
138 {
139 .compatible = "maxim,max6650",
140 .data = (void *)1
141 },
142 {
143 .compatible = "maxim,max6651",
144 .data = (void *)4
145 },
146 { },
147};
148MODULE_DEVICE_TABLE(of, max6650_dt_match);
149
1577f94b
GR		 150static struct max6650_data *max6650_update_device(struct device *dev)
151{
17eaa25c
GR		 152 struct max6650_data *data = dev_get_drvdata(dev);
153 struct i2c_client *client = data->client;
1577f94b 154 int i;
1577f94b
GR		 155
156 mutex_lock(&data->update_lock);
157
158 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
159 data->speed = i2c_smbus_read_byte_data(client,
160 MAX6650_REG_SPEED);
161 data->config = i2c_smbus_read_byte_data(client,
162 MAX6650_REG_CONFIG);
163 for (i = 0; i < data->nr_fans; i++) {
164 data->tach[i] = i2c_smbus_read_byte_data(client,
165 tach_reg[i]);
166 }
167 data->count = i2c_smbus_read_byte_data(client,
168 MAX6650_REG_COUNT);
169 data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
170
171 /*
172 * Alarms are cleared on read in case the condition that
173 * caused the alarm is removed. Keep the value latched here
174 * for providing the register through different alarm files.
175 */
176 data->alarm |= i2c_smbus_read_byte_data(client,
177 MAX6650_REG_ALARM);
178
179 data->last_updated = jiffies;
180 data->valid = 1;
181 }
182
183 mutex_unlock(&data->update_lock);
184
185 return data;
186}
187
20005cc5
ML		 188/*
189 * Change the operating mode of the chip (if needed).
190 * mode is one of the MAX6650_CFG_MODE_* values.
191 */
192static int max6650_set_operating_mode(struct max6650_data *data, u8 mode)
193{
194 int result;
195 u8 config = data->config;
196
197 if (mode == (config & MAX6650_CFG_MODE_MASK))
198 return 0;
199
200 config = (config & ~MAX6650_CFG_MODE_MASK) | mode;
201
202 result = i2c_smbus_write_byte_data(data->client, MAX6650_REG_CONFIG,
203 config);
204 if (result < 0)
205 return result;
206
207 data->config = config;
208
209 return 0;
210}
211
d20620de
HJK		 212static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
213 char *buf)
214{
215 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
216 struct max6650_data *data = max6650_update_device(dev);
217 int rpm;
218
219 /*
703af960
GR		 220 * Calculation details:
221 *
222 * Each tachometer counts over an interval given by the "count"
223 * register (0.25, 0.5, 1 or 2 seconds). This module assumes
224 * that the fans produce two pulses per revolution (this seems
225 * to be the most common).
226 */
d20620de
HJK		 227
228 rpm = ((data->tach[attr->index] * 120) / DIV_FROM_REG(data->count));
229 return sprintf(buf, "%d\n", rpm);
230}
231
232/*
233 * Set the fan speed to the specified RPM (or read back the RPM setting).
234 * This works in closed loop mode only. Use pwm1 for open loop speed setting.
235 *
236 * The MAX6650/1 will automatically control fan speed when in closed loop
237 * mode.
238 *
239 * Assumptions:
240 *
241 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use
242 * the clock module parameter if you need to fine tune this.
243 *
244 * 2) The prescaler (low three bits of the config register) has already
245 * been set to an appropriate value. Use the prescaler module parameter
246 * if your BIOS doesn't initialize the chip properly.
247 *
248 * The relevant equations are given on pages 21 and 22 of the datasheet.
249 *
250 * From the datasheet, the relevant equation when in regulation is:
251 *
252 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE
253 *
254 * where:
255 *
256 * fCLK is the oscillator frequency (either the 254kHz internal
257 * oscillator or the externally applied clock)
258 *
259 * KTACH is the value in the speed register
260 *
261 * FanSpeed is the speed of the fan in rps
262 *
263 * KSCALE is the prescaler value (1, 2, 4, 8, or 16)
264 *
265 * When reading, we need to solve for FanSpeed. When writing, we need to
266 * solve for KTACH.
267 *
268 * Note: this tachometer is completely separate from the tachometers
269 * used to measure the fan speeds. Only one fan's speed (fan1) is
270 * controlled.
271 */
272
273static ssize_t get_target(struct device *dev, struct device_attribute *devattr,
274 char *buf)
275{
276 struct max6650_data *data = max6650_update_device(dev);
277 int kscale, ktach, rpm;
278
279 /*
703af960
GR		 280 * Use the datasheet equation:
281 *
282 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)]
283 *
284 * then multiply by 60 to give rpm.
285 */
d20620de
HJK		 286
287 kscale = DIV_FROM_REG(data->config);
288 ktach = data->speed;
289 rpm = 60 * kscale * clock / (256 * (ktach + 1));
290 return sprintf(buf, "%d\n", rpm);
291}
292
20005cc5 293static int max6650_set_target(struct max6650_data *data, unsigned long rpm)
d20620de 294{
d20620de 295 int kscale, ktach;
bafda5d0 296
20005cc5
ML		 297 if (rpm == 0)
298 return max6650_set_operating_mode(data, MAX6650_CFG_MODE_OFF);
d20620de 299
2a844c14 300 rpm = clamp_val(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
d20620de
HJK		 301
302 /*
703af960
GR		 303 * Divide the required speed by 60 to get from rpm to rps, then
304 * use the datasheet equation:
305 *
306 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
307 */
d20620de 308
d20620de
HJK		 309 kscale = DIV_FROM_REG(data->config);
310 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
311 if (ktach < 0)
312 ktach = 0;
313 if (ktach > 255)
314 ktach = 255;
315 data->speed = ktach;
316
20005cc5
ML		 317 return i2c_smbus_write_byte_data(data->client, MAX6650_REG_SPEED,
318 data->speed);
319}
320
321static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
322 const char *buf, size_t count)
323{
324 struct max6650_data *data = dev_get_drvdata(dev);
325 unsigned long rpm;
326 int err;
327
328 err = kstrtoul(buf, 10, &rpm);
329 if (err)
330 return err;
331
332 mutex_lock(&data->update_lock);
333
334 err = max6650_set_target(data, rpm);
d20620de
HJK		 335
336 mutex_unlock(&data->update_lock);
337
20005cc5
ML		 338 if (err < 0)
339 return err;
340
d20620de
HJK		 341 return count;
342}
343
344/*
345 * Get/set the fan speed in open loop mode using pwm1 sysfs file.
346 * Speed is given as a relative value from 0 to 255, where 255 is maximum
347 * speed. Note that this is done by writing directly to the chip's DAC,
348 * it won't change the closed loop speed set by fan1_target.
349 * Also note that due to rounding errors it is possible that you don't read
350 * back exactly the value you have set.
351 */
352
353static ssize_t get_pwm(struct device *dev, struct device_attribute *devattr,
354 char *buf)
355{
356 int pwm;
357 struct max6650_data *data = max6650_update_device(dev);
358
703af960
GR		 359 /*
360 * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
361 * Lower DAC values mean higher speeds.
362 */
d20620de
HJK		 363 if (data->config & MAX6650_CFG_V12)
364 pwm = 255 - (255 * (int)data->dac)/180;
365 else
366 pwm = 255 - (255 * (int)data->dac)/76;
367
368 if (pwm < 0)
369 pwm = 0;
370
371 return sprintf(buf, "%d\n", pwm);
372}
373
374static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
375 const char *buf, size_t count)
376{
17eaa25c
GR		 377 struct max6650_data *data = dev_get_drvdata(dev);
378 struct i2c_client *client = data->client;
bafda5d0
GR		 379 unsigned long pwm;
380 int err;
381
382 err = kstrtoul(buf, 10, &pwm);
383 if (err)
384 return err;
d20620de 385
2a844c14 386 pwm = clamp_val(pwm, 0, 255);
d20620de
HJK		 387
388 mutex_lock(&data->update_lock);
389
390 if (data->config & MAX6650_CFG_V12)
391 data->dac = 180 - (180 * pwm)/255;
392 else
393 data->dac = 76 - (76 * pwm)/255;
20005cc5 394 err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
d20620de
HJK		 395
396 mutex_unlock(&data->update_lock);
397
20005cc5 398 return err < 0 ? err : count;
d20620de
HJK		 399}
400
401/*
402 * Get/Set controller mode:
403 * Possible values:
404 * 0 = Fan always on
405 * 1 = Open loop, Voltage is set according to speed, not regulated.
406 * 2 = Closed loop, RPM for all fans regulated by fan1 tachometer
20005cc5 407 * 3 = Fan off
d20620de 408 */
d20620de
HJK		 409static ssize_t get_enable(struct device *dev, struct device_attribute *devattr,
410 char *buf)
411{
412 struct max6650_data *data = max6650_update_device(dev);
413 int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
20005cc5 414 int sysfs_modes[4] = {0, 3, 2, 1};
d20620de
HJK		 415
416 return sprintf(buf, "%d\n", sysfs_modes[mode]);
417}
418
419static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,
420 const char *buf, size_t count)
421{
17eaa25c 422 struct max6650_data *data = dev_get_drvdata(dev);
bafda5d0
GR		 423 unsigned long mode;
424 int err;
20005cc5
ML		 425 const u8 max6650_modes[] = {
426 MAX6650_CFG_MODE_ON,
427 MAX6650_CFG_MODE_OPEN_LOOP,
428 MAX6650_CFG_MODE_CLOSED_LOOP,
429 MAX6650_CFG_MODE_OFF,
430 };
bafda5d0
GR		 431
432 err = kstrtoul(buf, 10, &mode);
433 if (err)
434 return err;
d20620de 435
20005cc5 436 if (mode >= ARRAY_SIZE(max6650_modes))
d20620de 437 return -EINVAL;
d20620de
HJK		 438
439 mutex_lock(&data->update_lock);
440
20005cc5 441 max6650_set_operating_mode(data, max6650_modes[mode]);
d20620de
HJK		 442
443 mutex_unlock(&data->update_lock);
444
445 return count;
446}
447
448/*
449 * Read/write functions for fan1_div sysfs file. The MAX6650 has no such
450 * divider. We handle this by converting between divider and counttime:
451 *
452 * (counttime == k) <==> (divider == 2^k), k = 0, 1, 2, or 3
453 *
454 * Lower values of k allow to connect a faster fan without the risk of
455 * counter overflow. The price is lower resolution. You can also set counttime
456 * using the module parameter. Note that the module parameter "prescaler" also
457 * influences the behaviour. Unfortunately, there's no sysfs attribute
458 * defined for that. See the data sheet for details.
459 */
460
461static ssize_t get_div(struct device *dev, struct device_attribute *devattr,
462 char *buf)
463{
464 struct max6650_data *data = max6650_update_device(dev);
465
466 return sprintf(buf, "%d\n", DIV_FROM_REG(data->count));
467}
468
469static ssize_t set_div(struct device *dev, struct device_attribute *devattr,
470 const char *buf, size_t count)
471{
17eaa25c
GR		 472 struct max6650_data *data = dev_get_drvdata(dev);
473 struct i2c_client *client = data->client;
bafda5d0
GR		 474 unsigned long div;
475 int err;
476
477 err = kstrtoul(buf, 10, &div);
478 if (err)
479 return err;
d20620de
HJK		 480
481 mutex_lock(&data->update_lock);
482 switch (div) {
483 case 1:
484 data->count = 0;
485 break;
486 case 2:
487 data->count = 1;
488 break;
489 case 4:
490 data->count = 2;
491 break;
492 case 8:
493 data->count = 3;
494 break;
495 default:
025dc740 496 mutex_unlock(&data->update_lock);
d20620de
HJK		 497 return -EINVAL;
498 }
499
500 i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count);
501 mutex_unlock(&data->update_lock);
502
503 return count;
504}
505
52b5226f
CE		 506/*
507 * Get alarm stati:
508 * Possible values:
509 * 0 = no alarm
510 * 1 = alarm
511 */
512
513static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr,
514 char *buf)
515{
516 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
517 struct max6650_data *data = max6650_update_device(dev);
17eaa25c 518 struct i2c_client *client = data->client;
52b5226f
CE		 519 int alarm = 0;
520
521 if (data->alarm & attr->index) {
522 mutex_lock(&data->update_lock);
523 alarm = 1;
524 data->alarm &= ~attr->index;
525 data->alarm |= i2c_smbus_read_byte_data(client,
526 MAX6650_REG_ALARM);
527 mutex_unlock(&data->update_lock);
528 }
529
530 return sprintf(buf, "%d\n", alarm);
531}
532
d20620de
HJK		 533static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0);
534static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1);
535static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2);
536static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, get_fan, NULL, 3);
537static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, get_target, set_target);
538static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div);
539static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable);
540static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
52b5226f
CE		 541static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, get_alarm, NULL,
542 MAX6650_ALRM_MAX);
543static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, get_alarm, NULL,
544 MAX6650_ALRM_MIN);
545static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_alarm, NULL,
546 MAX6650_ALRM_TACH);
547static SENSOR_DEVICE_ATTR(gpio1_alarm, S_IRUGO, get_alarm, NULL,
548 MAX6650_ALRM_GPIO1);
549static SENSOR_DEVICE_ATTR(gpio2_alarm, S_IRUGO, get_alarm, NULL,
550 MAX6650_ALRM_GPIO2);
551
587a1f16 552static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
52b5226f
CE		 553 int n)
554{
555 struct device *dev = container_of(kobj, struct device, kobj);
17eaa25c
GR		 556 struct max6650_data *data = dev_get_drvdata(dev);
557 struct i2c_client *client = data->client;
52b5226f
CE		 558 u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
559 struct device_attribute *devattr;
d20620de 560
52b5226f
CE		 561 /*
562 * Hide the alarms that have not been enabled by the firmware
563 */
564
565 devattr = container_of(a, struct device_attribute, attr);
566 if (devattr == &sensor_dev_attr_fan1_max_alarm.dev_attr
567 || devattr == &sensor_dev_attr_fan1_min_alarm.dev_attr
568 || devattr == &sensor_dev_attr_fan1_fault.dev_attr
569 || devattr == &sensor_dev_attr_gpio1_alarm.dev_attr
570 || devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
571 if (!(alarm_en & to_sensor_dev_attr(devattr)->index))
572 return 0;
573 }
574
575 return a->mode;
576}
d20620de
HJK		 577
578static struct attribute *max6650_attrs[] = {
579 &sensor_dev_attr_fan1_input.dev_attr.attr,
d20620de
HJK		 580 &dev_attr_fan1_target.attr,
581 &dev_attr_fan1_div.attr,
582 &dev_attr_pwm1_enable.attr,
583 &dev_attr_pwm1.attr,
52b5226f
CE		 584 &sensor_dev_attr_fan1_max_alarm.dev_attr.attr,
585 &sensor_dev_attr_fan1_min_alarm.dev_attr.attr,
586 &sensor_dev_attr_fan1_fault.dev_attr.attr,
587 &sensor_dev_attr_gpio1_alarm.dev_attr.attr,
588 &sensor_dev_attr_gpio2_alarm.dev_attr.attr,
d20620de
HJK		 589 NULL
590};
591
17eaa25c 592static const struct attribute_group max6650_group = {
d20620de 593 .attrs = max6650_attrs,
52b5226f 594 .is_visible = max6650_attrs_visible,
d20620de
HJK		 595};
596
9c084dae
JD		 597static struct attribute *max6651_attrs[] = {
598 &sensor_dev_attr_fan2_input.dev_attr.attr,
599 &sensor_dev_attr_fan3_input.dev_attr.attr,
600 &sensor_dev_attr_fan4_input.dev_attr.attr,
601 NULL
602};
603
17eaa25c 604static const struct attribute_group max6651_group = {
9c084dae
JD		 605 .attrs = max6651_attrs,
606};
607
d20620de
HJK		 608/*
609 * Real code
610 */
611
17eaa25c
GR		 612static int max6650_init_client(struct max6650_data *data,
613 struct i2c_client *client)
d20620de 614{
71ba0f31 615 struct device *dev = &client->dev;
d20620de
HJK		 616 int config;
617 int err = -EIO;
a6cdeefe
ML		 618 u32 voltage;
619 u32 prescale;
20005cc5 620 u32 target_rpm;
a6cdeefe
ML		 621
622 if (of_property_read_u32(dev->of_node, "maxim,fan-microvolt",
623 &voltage))
624 voltage = fan_voltage;
625 else
626 voltage /= 1000000; /* Microvolts to volts */
627 if (of_property_read_u32(dev->of_node, "maxim,fan-prescale",
628 &prescale))
629 prescale = prescaler;
d20620de
HJK		 630
631 config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
632
633 if (config < 0) {
71ba0f31 634 dev_err(dev, "Error reading config, aborting.\n");
d20620de
HJK		 635 return err;
636 }
637
a6cdeefe 638 switch (voltage) {
bafda5d0
GR		 639 case 0:
640 break;
641 case 5:
642 config &= ~MAX6650_CFG_V12;
643 break;
644 case 12:
645 config |= MAX6650_CFG_V12;
646 break;
647 default:
a6cdeefe 648 dev_err(dev, "illegal value for fan_voltage (%d)\n", voltage);
d20620de
HJK		 649 }
650
a6cdeefe 651 switch (prescale) {
bafda5d0
GR		 652 case 0:
653 break;
654 case 1:
655 config &= ~MAX6650_CFG_PRESCALER_MASK;
656 break;
657 case 2:
658 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
659 | MAX6650_CFG_PRESCALER_2;
660 break;
661 case 4:
662 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
663 | MAX6650_CFG_PRESCALER_4;
664 break;
665 case 8:
666 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
667 | MAX6650_CFG_PRESCALER_8;
668 break;
669 case 16:
670 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
671 | MAX6650_CFG_PRESCALER_16;
672 break;
673 default:
a6cdeefe 674 dev_err(dev, "illegal value for prescaler (%d)\n", prescale);
d20620de
HJK		 675 }
676
a6cdeefe
ML		 677 dev_info(dev, "Fan voltage: %dV, prescaler: %d.\n",
678 (config & MAX6650_CFG_V12) ? 12 : 5,
d20620de
HJK		 679 1 << (config & MAX6650_CFG_PRESCALER_MASK));
680
d20620de 681 if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) {
71ba0f31 682 dev_err(dev, "Config write error, aborting.\n");
d20620de
HJK		 683 return err;
684 }
685
686 data->config = config;
687 data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
688
20005cc5
ML		 689 if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm",
690 &target_rpm)) {
691 max6650_set_target(data, target_rpm);
692 max6650_set_operating_mode(data, MAX6650_CFG_MODE_CLOSED_LOOP);
693 }
694
d20620de
HJK		 695 return 0;
696}
697
1577f94b
GR		 698static int max6650_probe(struct i2c_client *client,
699 const struct i2c_device_id *id)
d20620de 700{
71ba0f31 701 struct device *dev = &client->dev;
a6cdeefe
ML		 702 const struct of_device_id *of_id =
703 of_match_device(of_match_ptr(max6650_dt_match), dev);
1577f94b 704 struct max6650_data *data;
17eaa25c 705 struct device *hwmon_dev;
1577f94b 706 int err;
d20620de 707
71ba0f31 708 data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL);
0b5e33b6 709 if (!data)
1577f94b 710 return -ENOMEM;
d20620de 711
17eaa25c 712 data->client = client;
1577f94b 713 mutex_init(&data->update_lock);
a6cdeefe 714 data->nr_fans = of_id ? (int)(uintptr_t)of_id->data : id->driver_data;
d20620de 715
1577f94b
GR		 716 /*
717 * Initialize the max6650 chip
718 */
17eaa25c 719 err = max6650_init_client(data, client);
1577f94b
GR		 720 if (err)
721 return err;
52b5226f 722
17eaa25c 723 data->groups[0] = &max6650_group;
1577f94b 724 /* 3 additional fan inputs for the MAX6651 */
1577f94b 725 if (data->nr_fans == 4)
17eaa25c 726 data->groups[1] = &max6651_group;
1577f94b 727
71ba0f31 728 hwmon_dev = devm_hwmon_device_register_with_groups(dev,
17eaa25c
GR		 729 client->name, data,
730 data->groups);
731 return PTR_ERR_OR_ZERO(hwmon_dev);
1577f94b
GR		 732}
733
734static const struct i2c_device_id max6650_id[] = {
735 { "max6650", 1 },
736 { "max6651", 4 },
737 { }
738};
739MODULE_DEVICE_TABLE(i2c, max6650_id);
740
741static struct i2c_driver max6650_driver = {
742 .driver = {
743 .name = "max6650",
a6cdeefe 744 .of_match_table = of_match_ptr(max6650_dt_match),
1577f94b
GR		 745 },
746 .probe = max6650_probe,
1577f94b
GR		 747 .id_table = max6650_id,
748};
749
f0967eea 750module_i2c_driver(max6650_driver);
d20620de
HJK		 751
752MODULE_AUTHOR("Hans J. Koch");
753MODULE_DESCRIPTION("MAX6650 sensor driver");
754MODULE_LICENSE("GPL");
Linux 6.x block layer and io_uring tree(s)