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.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 * const 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	struct max6650_data *data;
767	struct device *hwmon_dev;
768	int err;
769
770	data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL);
771	if (!data)
772		return -ENOMEM;
773
774	data->client = client;
775	i2c_set_clientdata(client, data);
776	mutex_init(&data->update_lock);
777
778	data->nr_fans = (uintptr_t)i2c_get_match_data(client);
779
780	/*
781	 * Initialize the max6650 chip
782	 */
783	err = max6650_init_client(data, client);
784	if (err)
785		return err;
786
787	hwmon_dev = devm_hwmon_device_register_with_info(dev,
788							 client->name, data,
789							 &max6650_chip_info,
790							 max6650_groups);
791	err = PTR_ERR_OR_ZERO(hwmon_dev);
792	if (err)
793		return err;
794
795	if (IS_ENABLED(CONFIG_THERMAL)) {
796		cooling_dev = devm_thermal_of_cooling_device_register(dev,
797						dev->of_node, client->name,
798						data, &max6650_cooling_ops);
799		if (IS_ERR(cooling_dev)) {
800			dev_warn(dev, "thermal cooling device register failed: %ld\n",
801				 PTR_ERR(cooling_dev));
802		}
803	}
804
805	return 0;
806}
807
808static const struct i2c_device_id max6650_id[] = {
809	{ "max6650", 1 },
810	{ "max6651", 4 },
811	{ }
812};
813MODULE_DEVICE_TABLE(i2c, max6650_id);
814
815static struct i2c_driver max6650_driver = {
816	.driver = {
817		.name	= "max6650",
818		.of_match_table = of_match_ptr(max6650_dt_match),
819	},
820	.probe		= max6650_probe,
821	.id_table	= max6650_id,
822};
823
824module_i2c_driver(max6650_driver);
825
826MODULE_AUTHOR("Hans J. Koch");
827MODULE_DESCRIPTION("MAX6650 sensor driver");
828MODULE_LICENSE("GPL");
829