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v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * max31790.c - Part of lm_sensors, Linux kernel modules for hardware
  4 *             monitoring.
  5 *
  6 * (C) 2015 by Il Han <corone.il.han@gmail.com>
 
 
 
 
 
 
 
 
 
 
  7 */
  8
  9#include <linux/err.h>
 10#include <linux/hwmon.h>
 11#include <linux/i2c.h>
 12#include <linux/init.h>
 13#include <linux/jiffies.h>
 14#include <linux/module.h>
 15#include <linux/slab.h>
 16
 17/* MAX31790 registers */
 18#define MAX31790_REG_GLOBAL_CONFIG	0x00
 19#define MAX31790_REG_FAN_CONFIG(ch)	(0x02 + (ch))
 20#define MAX31790_REG_FAN_DYNAMICS(ch)	(0x08 + (ch))
 21#define MAX31790_REG_FAN_FAULT_STATUS2	0x10
 22#define MAX31790_REG_FAN_FAULT_STATUS1	0x11
 23#define MAX31790_REG_TACH_COUNT(ch)	(0x18 + (ch) * 2)
 24#define MAX31790_REG_PWM_DUTY_CYCLE(ch)	(0x30 + (ch) * 2)
 25#define MAX31790_REG_PWMOUT(ch)		(0x40 + (ch) * 2)
 26#define MAX31790_REG_TARGET_COUNT(ch)	(0x50 + (ch) * 2)
 27
 28/* Fan Config register bits */
 29#define MAX31790_FAN_CFG_RPM_MODE	0x80
 30#define MAX31790_FAN_CFG_CTRL_MON	0x10
 31#define MAX31790_FAN_CFG_TACH_INPUT_EN	0x08
 32#define MAX31790_FAN_CFG_TACH_INPUT	0x01
 33
 34/* Fan Dynamics register bits */
 35#define MAX31790_FAN_DYN_SR_SHIFT	5
 36#define MAX31790_FAN_DYN_SR_MASK	0xE0
 37#define SR_FROM_REG(reg)		(((reg) & MAX31790_FAN_DYN_SR_MASK) \
 38					 >> MAX31790_FAN_DYN_SR_SHIFT)
 39
 40#define FAN_RPM_MIN			120
 41#define FAN_RPM_MAX			7864320
 42
 43#define FAN_COUNT_REG_MAX		0xffe0
 44
 45#define RPM_FROM_REG(reg, sr)		(((reg) >> 4) ? \
 46					 ((60 * (sr) * 8192) / ((reg) >> 4)) : \
 47					 FAN_RPM_MAX)
 48#define RPM_TO_REG(rpm, sr)		((60 * (sr) * 8192) / ((rpm) * 2))
 49
 50#define NR_CHANNEL			6
 51
 52/*
 53 * Client data (each client gets its own)
 54 */
 55struct max31790_data {
 56	struct i2c_client *client;
 57	struct mutex update_lock;
 58	bool valid; /* zero until following fields are valid */
 59	unsigned long last_updated; /* in jiffies */
 60
 61	/* register values */
 62	u8 fan_config[NR_CHANNEL];
 63	u8 fan_dynamics[NR_CHANNEL];
 64	u16 fault_status;
 65	u16 tach[NR_CHANNEL * 2];
 66	u16 pwm[NR_CHANNEL];
 67	u16 target_count[NR_CHANNEL];
 68};
 69
 70static struct max31790_data *max31790_update_device(struct device *dev)
 71{
 72	struct max31790_data *data = dev_get_drvdata(dev);
 73	struct i2c_client *client = data->client;
 74	struct max31790_data *ret = data;
 75	int i;
 76	int rv;
 77
 78	mutex_lock(&data->update_lock);
 79
 80	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
 81		rv = i2c_smbus_read_byte_data(client,
 82				MAX31790_REG_FAN_FAULT_STATUS1);
 83		if (rv < 0)
 84			goto abort;
 85		data->fault_status |= rv & 0x3F;
 86
 87		rv = i2c_smbus_read_byte_data(client,
 88				MAX31790_REG_FAN_FAULT_STATUS2);
 89		if (rv < 0)
 90			goto abort;
 91		data->fault_status |= (rv & 0x3F) << 6;
 92
 93		for (i = 0; i < NR_CHANNEL; i++) {
 94			rv = i2c_smbus_read_word_swapped(client,
 95					MAX31790_REG_TACH_COUNT(i));
 96			if (rv < 0)
 97				goto abort;
 98			data->tach[i] = rv;
 99
100			if (data->fan_config[i]
101			    & MAX31790_FAN_CFG_TACH_INPUT) {
102				rv = i2c_smbus_read_word_swapped(client,
103					MAX31790_REG_TACH_COUNT(NR_CHANNEL
104								+ i));
105				if (rv < 0)
106					goto abort;
107				data->tach[NR_CHANNEL + i] = rv;
108			} else {
109				rv = i2c_smbus_read_word_swapped(client,
110						MAX31790_REG_PWM_DUTY_CYCLE(i));
111				if (rv < 0)
112					goto abort;
113				data->pwm[i] = rv;
114
115				rv = i2c_smbus_read_word_swapped(client,
116						MAX31790_REG_TARGET_COUNT(i));
117				if (rv < 0)
118					goto abort;
119				data->target_count[i] = rv;
120			}
121		}
122
123		data->last_updated = jiffies;
124		data->valid = true;
125	}
126	goto done;
127
128abort:
129	data->valid = false;
130	ret = ERR_PTR(rv);
131
132done:
133	mutex_unlock(&data->update_lock);
134
135	return ret;
136}
137
138static const u8 tach_period[8] = { 1, 2, 4, 8, 16, 32, 32, 32 };
139
140static u8 get_tach_period(u8 fan_dynamics)
141{
142	return tach_period[SR_FROM_REG(fan_dynamics)];
143}
144
145static u8 bits_for_tach_period(int rpm)
146{
147	u8 bits;
148
149	if (rpm < 500)
150		bits = 0x0;
151	else if (rpm < 1000)
152		bits = 0x1;
153	else if (rpm < 2000)
154		bits = 0x2;
155	else if (rpm < 4000)
156		bits = 0x3;
157	else if (rpm < 8000)
158		bits = 0x4;
159	else
160		bits = 0x5;
161
162	return bits;
163}
164
165static int max31790_read_fan(struct device *dev, u32 attr, int channel,
166			     long *val)
167{
168	struct max31790_data *data = max31790_update_device(dev);
169	int sr, rpm;
170
171	if (IS_ERR(data))
172		return PTR_ERR(data);
173
174	switch (attr) {
175	case hwmon_fan_input:
176		sr = get_tach_period(data->fan_dynamics[channel % NR_CHANNEL]);
177		if (data->tach[channel] == FAN_COUNT_REG_MAX)
178			rpm = 0;
179		else
180			rpm = RPM_FROM_REG(data->tach[channel], sr);
181		*val = rpm;
182		return 0;
183	case hwmon_fan_target:
184		sr = get_tach_period(data->fan_dynamics[channel]);
185		rpm = RPM_FROM_REG(data->target_count[channel], sr);
186		*val = rpm;
187		return 0;
188	case hwmon_fan_fault:
189		mutex_lock(&data->update_lock);
190		*val = !!(data->fault_status & (1 << channel));
191		data->fault_status &= ~(1 << channel);
192		/*
193		 * If a fault bit is set, we need to write into one of the fan
194		 * configuration registers to clear it. Note that this also
195		 * clears the fault for the companion channel if enabled.
196		 */
197		if (*val) {
198			int reg = MAX31790_REG_TARGET_COUNT(channel % NR_CHANNEL);
199
200			i2c_smbus_write_byte_data(data->client, reg,
201						  data->target_count[channel % NR_CHANNEL] >> 8);
202		}
203		mutex_unlock(&data->update_lock);
204		return 0;
205	case hwmon_fan_enable:
206		*val = !!(data->fan_config[channel] & MAX31790_FAN_CFG_TACH_INPUT_EN);
207		return 0;
208	default:
209		return -EOPNOTSUPP;
210	}
211}
212
213static int max31790_write_fan(struct device *dev, u32 attr, int channel,
214			      long val)
215{
216	struct max31790_data *data = dev_get_drvdata(dev);
217	struct i2c_client *client = data->client;
218	int target_count;
219	int err = 0;
220	u8 bits, fan_config;
221	int sr;
222
223	mutex_lock(&data->update_lock);
224
225	switch (attr) {
226	case hwmon_fan_target:
227		val = clamp_val(val, FAN_RPM_MIN, FAN_RPM_MAX);
228		bits = bits_for_tach_period(val);
229		data->fan_dynamics[channel] =
230			((data->fan_dynamics[channel] &
231			  ~MAX31790_FAN_DYN_SR_MASK) |
232			 (bits << MAX31790_FAN_DYN_SR_SHIFT));
233		err = i2c_smbus_write_byte_data(client,
234					MAX31790_REG_FAN_DYNAMICS(channel),
235					data->fan_dynamics[channel]);
236		if (err < 0)
237			break;
238
239		sr = get_tach_period(data->fan_dynamics[channel]);
240		target_count = RPM_TO_REG(val, sr);
241		target_count = clamp_val(target_count, 0x1, 0x7FF);
242
243		data->target_count[channel] = target_count << 5;
244
245		err = i2c_smbus_write_word_swapped(client,
246					MAX31790_REG_TARGET_COUNT(channel),
247					data->target_count[channel]);
248		break;
249	case hwmon_fan_enable:
250		fan_config = data->fan_config[channel];
251		if (val == 0) {
252			fan_config &= ~MAX31790_FAN_CFG_TACH_INPUT_EN;
253		} else if (val == 1) {
254			fan_config |= MAX31790_FAN_CFG_TACH_INPUT_EN;
255		} else {
256			err = -EINVAL;
257			break;
258		}
259		if (fan_config != data->fan_config[channel]) {
260			err = i2c_smbus_write_byte_data(client, MAX31790_REG_FAN_CONFIG(channel),
261							fan_config);
262			if (!err)
263				data->fan_config[channel] = fan_config;
264		}
265		break;
266	default:
267		err = -EOPNOTSUPP;
268		break;
269	}
270
271	mutex_unlock(&data->update_lock);
272
273	return err;
274}
275
276static umode_t max31790_fan_is_visible(const void *_data, u32 attr, int channel)
277{
278	const struct max31790_data *data = _data;
279	u8 fan_config = data->fan_config[channel % NR_CHANNEL];
280
281	switch (attr) {
282	case hwmon_fan_input:
283	case hwmon_fan_fault:
284		if (channel < NR_CHANNEL ||
285		    (fan_config & MAX31790_FAN_CFG_TACH_INPUT))
286			return 0444;
287		return 0;
288	case hwmon_fan_target:
289		if (channel < NR_CHANNEL &&
290		    !(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
291			return 0644;
292		return 0;
293	case hwmon_fan_enable:
294		if (channel < NR_CHANNEL)
295			return 0644;
296		return 0;
297	default:
298		return 0;
299	}
300}
301
302static int max31790_read_pwm(struct device *dev, u32 attr, int channel,
303			     long *val)
304{
305	struct max31790_data *data = max31790_update_device(dev);
306	u8 fan_config;
307
308	if (IS_ERR(data))
309		return PTR_ERR(data);
310
311	fan_config = data->fan_config[channel];
312
313	switch (attr) {
314	case hwmon_pwm_input:
315		*val = data->pwm[channel] >> 8;
316		return 0;
317	case hwmon_pwm_enable:
318		if (fan_config & MAX31790_FAN_CFG_CTRL_MON)
319			*val = 0;
320		else if (fan_config & MAX31790_FAN_CFG_RPM_MODE)
321			*val = 2;
322		else
323			*val = 1;
 
 
324		return 0;
325	default:
326		return -EOPNOTSUPP;
327	}
328}
329
330static int max31790_write_pwm(struct device *dev, u32 attr, int channel,
331			      long val)
332{
333	struct max31790_data *data = dev_get_drvdata(dev);
334	struct i2c_client *client = data->client;
335	u8 fan_config;
336	int err = 0;
337
338	mutex_lock(&data->update_lock);
339
340	switch (attr) {
341	case hwmon_pwm_input:
342		if (val < 0 || val > 255) {
343			err = -EINVAL;
344			break;
345		}
346		data->valid = false;
347		err = i2c_smbus_write_word_swapped(client,
348						   MAX31790_REG_PWMOUT(channel),
349						   val << 8);
350		break;
351	case hwmon_pwm_enable:
352		fan_config = data->fan_config[channel];
353		if (val == 0) {
354			fan_config |= MAX31790_FAN_CFG_CTRL_MON;
355			/*
356			 * Disable RPM mode; otherwise disabling fan speed
357			 * monitoring is not possible.
358			 */
359			fan_config &= ~MAX31790_FAN_CFG_RPM_MODE;
360		} else if (val == 1) {
361			fan_config &= ~(MAX31790_FAN_CFG_CTRL_MON | MAX31790_FAN_CFG_RPM_MODE);
 
 
362		} else if (val == 2) {
363			fan_config &= ~MAX31790_FAN_CFG_CTRL_MON;
364			/*
365			 * The chip sets MAX31790_FAN_CFG_TACH_INPUT_EN on its
366			 * own if MAX31790_FAN_CFG_RPM_MODE is set.
367			 * Do it here as well to reflect the actual register
368			 * value in the cache.
369			 */
370			fan_config |= (MAX31790_FAN_CFG_RPM_MODE | MAX31790_FAN_CFG_TACH_INPUT_EN);
371		} else {
372			err = -EINVAL;
373			break;
374		}
375		if (fan_config != data->fan_config[channel]) {
376			err = i2c_smbus_write_byte_data(client, MAX31790_REG_FAN_CONFIG(channel),
377							fan_config);
378			if (!err)
379				data->fan_config[channel] = fan_config;
380		}
381		break;
382	default:
383		err = -EOPNOTSUPP;
384		break;
385	}
386
387	mutex_unlock(&data->update_lock);
388
389	return err;
390}
391
392static umode_t max31790_pwm_is_visible(const void *_data, u32 attr, int channel)
393{
394	const struct max31790_data *data = _data;
395	u8 fan_config = data->fan_config[channel];
396
397	switch (attr) {
398	case hwmon_pwm_input:
399	case hwmon_pwm_enable:
400		if (!(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
401			return 0644;
402		return 0;
403	default:
404		return 0;
405	}
406}
407
408static int max31790_read(struct device *dev, enum hwmon_sensor_types type,
409			 u32 attr, int channel, long *val)
410{
411	switch (type) {
412	case hwmon_fan:
413		return max31790_read_fan(dev, attr, channel, val);
414	case hwmon_pwm:
415		return max31790_read_pwm(dev, attr, channel, val);
416	default:
417		return -EOPNOTSUPP;
418	}
419}
420
421static int max31790_write(struct device *dev, enum hwmon_sensor_types type,
422			  u32 attr, int channel, long val)
423{
424	switch (type) {
425	case hwmon_fan:
426		return max31790_write_fan(dev, attr, channel, val);
427	case hwmon_pwm:
428		return max31790_write_pwm(dev, attr, channel, val);
429	default:
430		return -EOPNOTSUPP;
431	}
432}
433
434static umode_t max31790_is_visible(const void *data,
435				   enum hwmon_sensor_types type,
436				   u32 attr, int channel)
437{
438	switch (type) {
439	case hwmon_fan:
440		return max31790_fan_is_visible(data, attr, channel);
441	case hwmon_pwm:
442		return max31790_pwm_is_visible(data, attr, channel);
443	default:
444		return 0;
445	}
446}
447
448static const struct hwmon_channel_info * const max31790_info[] = {
449	HWMON_CHANNEL_INFO(fan,
450			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
451			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
452			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
453			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
454			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
455			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
456			   HWMON_F_INPUT | HWMON_F_FAULT,
457			   HWMON_F_INPUT | HWMON_F_FAULT,
458			   HWMON_F_INPUT | HWMON_F_FAULT,
459			   HWMON_F_INPUT | HWMON_F_FAULT,
460			   HWMON_F_INPUT | HWMON_F_FAULT,
461			   HWMON_F_INPUT | HWMON_F_FAULT),
462	HWMON_CHANNEL_INFO(pwm,
463			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
464			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
465			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
466			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
467			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
468			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
469	NULL
470};
471
472static const struct hwmon_ops max31790_hwmon_ops = {
473	.is_visible = max31790_is_visible,
474	.read = max31790_read,
475	.write = max31790_write,
476};
477
478static const struct hwmon_chip_info max31790_chip_info = {
479	.ops = &max31790_hwmon_ops,
480	.info = max31790_info,
481};
482
483static int max31790_init_client(struct i2c_client *client,
484				struct max31790_data *data)
485{
486	int i, rv;
487
488	for (i = 0; i < NR_CHANNEL; i++) {
489		rv = i2c_smbus_read_byte_data(client,
490				MAX31790_REG_FAN_CONFIG(i));
491		if (rv < 0)
492			return rv;
493		data->fan_config[i] = rv;
494
495		rv = i2c_smbus_read_byte_data(client,
496				MAX31790_REG_FAN_DYNAMICS(i));
497		if (rv < 0)
498			return rv;
499		data->fan_dynamics[i] = rv;
500	}
501
502	return 0;
503}
504
505static int max31790_probe(struct i2c_client *client)
 
506{
507	struct i2c_adapter *adapter = client->adapter;
508	struct device *dev = &client->dev;
509	struct max31790_data *data;
510	struct device *hwmon_dev;
511	int err;
512
513	if (!i2c_check_functionality(adapter,
514			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
515		return -ENODEV;
516
517	data = devm_kzalloc(dev, sizeof(struct max31790_data), GFP_KERNEL);
518	if (!data)
519		return -ENOMEM;
520
521	data->client = client;
522	mutex_init(&data->update_lock);
523
524	/*
525	 * Initialize the max31790 chip
526	 */
527	err = max31790_init_client(client, data);
528	if (err)
529		return err;
530
531	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
532							 data,
533							 &max31790_chip_info,
534							 NULL);
535
536	return PTR_ERR_OR_ZERO(hwmon_dev);
537}
538
539static const struct i2c_device_id max31790_id[] = {
540	{ "max31790", 0 },
541	{ }
542};
543MODULE_DEVICE_TABLE(i2c, max31790_id);
544
545static struct i2c_driver max31790_driver = {
546	.class		= I2C_CLASS_HWMON,
547	.probe		= max31790_probe,
548	.driver = {
549		.name	= "max31790",
550	},
551	.id_table	= max31790_id,
552};
553
554module_i2c_driver(max31790_driver);
555
556MODULE_AUTHOR("Il Han <corone.il.han@gmail.com>");
557MODULE_DESCRIPTION("MAX31790 sensor driver");
558MODULE_LICENSE("GPL");
v4.17
 
  1/*
  2 * max31790.c - Part of lm_sensors, Linux kernel modules for hardware
  3 *             monitoring.
  4 *
  5 * (C) 2015 by Il Han <corone.il.han@gmail.com>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 */
 17
 18#include <linux/err.h>
 19#include <linux/hwmon.h>
 20#include <linux/i2c.h>
 21#include <linux/init.h>
 22#include <linux/jiffies.h>
 23#include <linux/module.h>
 24#include <linux/slab.h>
 25
 26/* MAX31790 registers */
 27#define MAX31790_REG_GLOBAL_CONFIG	0x00
 28#define MAX31790_REG_FAN_CONFIG(ch)	(0x02 + (ch))
 29#define MAX31790_REG_FAN_DYNAMICS(ch)	(0x08 + (ch))
 30#define MAX31790_REG_FAN_FAULT_STATUS2	0x10
 31#define MAX31790_REG_FAN_FAULT_STATUS1	0x11
 32#define MAX31790_REG_TACH_COUNT(ch)	(0x18 + (ch) * 2)
 33#define MAX31790_REG_PWM_DUTY_CYCLE(ch)	(0x30 + (ch) * 2)
 34#define MAX31790_REG_PWMOUT(ch)		(0x40 + (ch) * 2)
 35#define MAX31790_REG_TARGET_COUNT(ch)	(0x50 + (ch) * 2)
 36
 37/* Fan Config register bits */
 38#define MAX31790_FAN_CFG_RPM_MODE	0x80
 
 39#define MAX31790_FAN_CFG_TACH_INPUT_EN	0x08
 40#define MAX31790_FAN_CFG_TACH_INPUT	0x01
 41
 42/* Fan Dynamics register bits */
 43#define MAX31790_FAN_DYN_SR_SHIFT	5
 44#define MAX31790_FAN_DYN_SR_MASK	0xE0
 45#define SR_FROM_REG(reg)		(((reg) & MAX31790_FAN_DYN_SR_MASK) \
 46					 >> MAX31790_FAN_DYN_SR_SHIFT)
 47
 48#define FAN_RPM_MIN			120
 49#define FAN_RPM_MAX			7864320
 50
 
 
 51#define RPM_FROM_REG(reg, sr)		(((reg) >> 4) ? \
 52					 ((60 * (sr) * 8192) / ((reg) >> 4)) : \
 53					 FAN_RPM_MAX)
 54#define RPM_TO_REG(rpm, sr)		((60 * (sr) * 8192) / ((rpm) * 2))
 55
 56#define NR_CHANNEL			6
 57
 58/*
 59 * Client data (each client gets its own)
 60 */
 61struct max31790_data {
 62	struct i2c_client *client;
 63	struct mutex update_lock;
 64	bool valid; /* zero until following fields are valid */
 65	unsigned long last_updated; /* in jiffies */
 66
 67	/* register values */
 68	u8 fan_config[NR_CHANNEL];
 69	u8 fan_dynamics[NR_CHANNEL];
 70	u16 fault_status;
 71	u16 tach[NR_CHANNEL * 2];
 72	u16 pwm[NR_CHANNEL];
 73	u16 target_count[NR_CHANNEL];
 74};
 75
 76static struct max31790_data *max31790_update_device(struct device *dev)
 77{
 78	struct max31790_data *data = dev_get_drvdata(dev);
 79	struct i2c_client *client = data->client;
 80	struct max31790_data *ret = data;
 81	int i;
 82	int rv;
 83
 84	mutex_lock(&data->update_lock);
 85
 86	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
 87		rv = i2c_smbus_read_byte_data(client,
 88				MAX31790_REG_FAN_FAULT_STATUS1);
 89		if (rv < 0)
 90			goto abort;
 91		data->fault_status = rv & 0x3F;
 92
 93		rv = i2c_smbus_read_byte_data(client,
 94				MAX31790_REG_FAN_FAULT_STATUS2);
 95		if (rv < 0)
 96			goto abort;
 97		data->fault_status |= (rv & 0x3F) << 6;
 98
 99		for (i = 0; i < NR_CHANNEL; i++) {
100			rv = i2c_smbus_read_word_swapped(client,
101					MAX31790_REG_TACH_COUNT(i));
102			if (rv < 0)
103				goto abort;
104			data->tach[i] = rv;
105
106			if (data->fan_config[i]
107			    & MAX31790_FAN_CFG_TACH_INPUT) {
108				rv = i2c_smbus_read_word_swapped(client,
109					MAX31790_REG_TACH_COUNT(NR_CHANNEL
110								+ i));
111				if (rv < 0)
112					goto abort;
113				data->tach[NR_CHANNEL + i] = rv;
114			} else {
115				rv = i2c_smbus_read_word_swapped(client,
116						MAX31790_REG_PWMOUT(i));
117				if (rv < 0)
118					goto abort;
119				data->pwm[i] = rv;
120
121				rv = i2c_smbus_read_word_swapped(client,
122						MAX31790_REG_TARGET_COUNT(i));
123				if (rv < 0)
124					goto abort;
125				data->target_count[i] = rv;
126			}
127		}
128
129		data->last_updated = jiffies;
130		data->valid = true;
131	}
132	goto done;
133
134abort:
135	data->valid = false;
136	ret = ERR_PTR(rv);
137
138done:
139	mutex_unlock(&data->update_lock);
140
141	return ret;
142}
143
144static const u8 tach_period[8] = { 1, 2, 4, 8, 16, 32, 32, 32 };
145
146static u8 get_tach_period(u8 fan_dynamics)
147{
148	return tach_period[SR_FROM_REG(fan_dynamics)];
149}
150
151static u8 bits_for_tach_period(int rpm)
152{
153	u8 bits;
154
155	if (rpm < 500)
156		bits = 0x0;
157	else if (rpm < 1000)
158		bits = 0x1;
159	else if (rpm < 2000)
160		bits = 0x2;
161	else if (rpm < 4000)
162		bits = 0x3;
163	else if (rpm < 8000)
164		bits = 0x4;
165	else
166		bits = 0x5;
167
168	return bits;
169}
170
171static int max31790_read_fan(struct device *dev, u32 attr, int channel,
172			     long *val)
173{
174	struct max31790_data *data = max31790_update_device(dev);
175	int sr, rpm;
176
177	if (IS_ERR(data))
178		return PTR_ERR(data);
179
180	switch (attr) {
181	case hwmon_fan_input:
182		sr = get_tach_period(data->fan_dynamics[channel]);
183		rpm = RPM_FROM_REG(data->tach[channel], sr);
 
 
 
184		*val = rpm;
185		return 0;
186	case hwmon_fan_target:
187		sr = get_tach_period(data->fan_dynamics[channel]);
188		rpm = RPM_FROM_REG(data->target_count[channel], sr);
189		*val = rpm;
190		return 0;
191	case hwmon_fan_fault:
 
192		*val = !!(data->fault_status & (1 << channel));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
193		return 0;
194	default:
195		return -EOPNOTSUPP;
196	}
197}
198
199static int max31790_write_fan(struct device *dev, u32 attr, int channel,
200			      long val)
201{
202	struct max31790_data *data = dev_get_drvdata(dev);
203	struct i2c_client *client = data->client;
204	int target_count;
205	int err = 0;
206	u8 bits;
207	int sr;
208
209	mutex_lock(&data->update_lock);
210
211	switch (attr) {
212	case hwmon_fan_target:
213		val = clamp_val(val, FAN_RPM_MIN, FAN_RPM_MAX);
214		bits = bits_for_tach_period(val);
215		data->fan_dynamics[channel] =
216			((data->fan_dynamics[channel] &
217			  ~MAX31790_FAN_DYN_SR_MASK) |
218			 (bits << MAX31790_FAN_DYN_SR_SHIFT));
219		err = i2c_smbus_write_byte_data(client,
220					MAX31790_REG_FAN_DYNAMICS(channel),
221					data->fan_dynamics[channel]);
222		if (err < 0)
223			break;
224
225		sr = get_tach_period(data->fan_dynamics[channel]);
226		target_count = RPM_TO_REG(val, sr);
227		target_count = clamp_val(target_count, 0x1, 0x7FF);
228
229		data->target_count[channel] = target_count << 5;
230
231		err = i2c_smbus_write_word_swapped(client,
232					MAX31790_REG_TARGET_COUNT(channel),
233					data->target_count[channel]);
234		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
235	default:
236		err = -EOPNOTSUPP;
237		break;
238	}
239
240	mutex_unlock(&data->update_lock);
241
242	return err;
243}
244
245static umode_t max31790_fan_is_visible(const void *_data, u32 attr, int channel)
246{
247	const struct max31790_data *data = _data;
248	u8 fan_config = data->fan_config[channel % NR_CHANNEL];
249
250	switch (attr) {
251	case hwmon_fan_input:
252	case hwmon_fan_fault:
253		if (channel < NR_CHANNEL ||
254		    (fan_config & MAX31790_FAN_CFG_TACH_INPUT))
255			return S_IRUGO;
256		return 0;
257	case hwmon_fan_target:
258		if (channel < NR_CHANNEL &&
259		    !(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
260			return S_IRUGO | S_IWUSR;
 
 
 
 
261		return 0;
262	default:
263		return 0;
264	}
265}
266
267static int max31790_read_pwm(struct device *dev, u32 attr, int channel,
268			     long *val)
269{
270	struct max31790_data *data = max31790_update_device(dev);
271	u8 fan_config;
272
273	if (IS_ERR(data))
274		return PTR_ERR(data);
275
276	fan_config = data->fan_config[channel];
277
278	switch (attr) {
279	case hwmon_pwm_input:
280		*val = data->pwm[channel] >> 8;
281		return 0;
282	case hwmon_pwm_enable:
283		if (fan_config & MAX31790_FAN_CFG_RPM_MODE)
 
 
284			*val = 2;
285		else if (fan_config & MAX31790_FAN_CFG_TACH_INPUT_EN)
286			*val = 1;
287		else
288			*val = 0;
289		return 0;
290	default:
291		return -EOPNOTSUPP;
292	}
293}
294
295static int max31790_write_pwm(struct device *dev, u32 attr, int channel,
296			      long val)
297{
298	struct max31790_data *data = dev_get_drvdata(dev);
299	struct i2c_client *client = data->client;
300	u8 fan_config;
301	int err = 0;
302
303	mutex_lock(&data->update_lock);
304
305	switch (attr) {
306	case hwmon_pwm_input:
307		if (val < 0 || val > 255) {
308			err = -EINVAL;
309			break;
310		}
311		data->pwm[channel] = val << 8;
312		err = i2c_smbus_write_word_swapped(client,
313						   MAX31790_REG_PWMOUT(channel),
314						   data->pwm[channel]);
315		break;
316	case hwmon_pwm_enable:
317		fan_config = data->fan_config[channel];
318		if (val == 0) {
319			fan_config &= ~(MAX31790_FAN_CFG_TACH_INPUT_EN |
320					MAX31790_FAN_CFG_RPM_MODE);
 
 
 
 
321		} else if (val == 1) {
322			fan_config = (fan_config |
323				      MAX31790_FAN_CFG_TACH_INPUT_EN) &
324				     ~MAX31790_FAN_CFG_RPM_MODE;
325		} else if (val == 2) {
326			fan_config |= MAX31790_FAN_CFG_TACH_INPUT_EN |
327				      MAX31790_FAN_CFG_RPM_MODE;
 
 
 
 
 
 
328		} else {
329			err = -EINVAL;
330			break;
331		}
332		data->fan_config[channel] = fan_config;
333		err = i2c_smbus_write_byte_data(client,
334					MAX31790_REG_FAN_CONFIG(channel),
335					fan_config);
 
 
336		break;
337	default:
338		err = -EOPNOTSUPP;
339		break;
340	}
341
342	mutex_unlock(&data->update_lock);
343
344	return err;
345}
346
347static umode_t max31790_pwm_is_visible(const void *_data, u32 attr, int channel)
348{
349	const struct max31790_data *data = _data;
350	u8 fan_config = data->fan_config[channel];
351
352	switch (attr) {
353	case hwmon_pwm_input:
354	case hwmon_pwm_enable:
355		if (!(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
356			return S_IRUGO | S_IWUSR;
357		return 0;
358	default:
359		return 0;
360	}
361}
362
363static int max31790_read(struct device *dev, enum hwmon_sensor_types type,
364			 u32 attr, int channel, long *val)
365{
366	switch (type) {
367	case hwmon_fan:
368		return max31790_read_fan(dev, attr, channel, val);
369	case hwmon_pwm:
370		return max31790_read_pwm(dev, attr, channel, val);
371	default:
372		return -EOPNOTSUPP;
373	}
374}
375
376static int max31790_write(struct device *dev, enum hwmon_sensor_types type,
377			  u32 attr, int channel, long val)
378{
379	switch (type) {
380	case hwmon_fan:
381		return max31790_write_fan(dev, attr, channel, val);
382	case hwmon_pwm:
383		return max31790_write_pwm(dev, attr, channel, val);
384	default:
385		return -EOPNOTSUPP;
386	}
387}
388
389static umode_t max31790_is_visible(const void *data,
390				   enum hwmon_sensor_types type,
391				   u32 attr, int channel)
392{
393	switch (type) {
394	case hwmon_fan:
395		return max31790_fan_is_visible(data, attr, channel);
396	case hwmon_pwm:
397		return max31790_pwm_is_visible(data, attr, channel);
398	default:
399		return 0;
400	}
401}
402
403static const u32 max31790_fan_config[] = {
404	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
405	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
406	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
407	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
408	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
409	HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT,
410	HWMON_F_INPUT | HWMON_F_FAULT,
411	HWMON_F_INPUT | HWMON_F_FAULT,
412	HWMON_F_INPUT | HWMON_F_FAULT,
413	HWMON_F_INPUT | HWMON_F_FAULT,
414	HWMON_F_INPUT | HWMON_F_FAULT,
415	HWMON_F_INPUT | HWMON_F_FAULT,
416	0
417};
418
419static const struct hwmon_channel_info max31790_fan = {
420	.type = hwmon_fan,
421	.config = max31790_fan_config,
422};
423
424static const u32 max31790_pwm_config[] = {
425	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
426	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
427	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
428	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
429	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
430	HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
431	0
432};
433
434static const struct hwmon_channel_info max31790_pwm = {
435	.type = hwmon_pwm,
436	.config = max31790_pwm_config,
437};
438
439static const struct hwmon_channel_info *max31790_info[] = {
440	&max31790_fan,
441	&max31790_pwm,
442	NULL
443};
444
445static const struct hwmon_ops max31790_hwmon_ops = {
446	.is_visible = max31790_is_visible,
447	.read = max31790_read,
448	.write = max31790_write,
449};
450
451static const struct hwmon_chip_info max31790_chip_info = {
452	.ops = &max31790_hwmon_ops,
453	.info = max31790_info,
454};
455
456static int max31790_init_client(struct i2c_client *client,
457				struct max31790_data *data)
458{
459	int i, rv;
460
461	for (i = 0; i < NR_CHANNEL; i++) {
462		rv = i2c_smbus_read_byte_data(client,
463				MAX31790_REG_FAN_CONFIG(i));
464		if (rv < 0)
465			return rv;
466		data->fan_config[i] = rv;
467
468		rv = i2c_smbus_read_byte_data(client,
469				MAX31790_REG_FAN_DYNAMICS(i));
470		if (rv < 0)
471			return rv;
472		data->fan_dynamics[i] = rv;
473	}
474
475	return 0;
476}
477
478static int max31790_probe(struct i2c_client *client,
479			  const struct i2c_device_id *id)
480{
481	struct i2c_adapter *adapter = client->adapter;
482	struct device *dev = &client->dev;
483	struct max31790_data *data;
484	struct device *hwmon_dev;
485	int err;
486
487	if (!i2c_check_functionality(adapter,
488			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
489		return -ENODEV;
490
491	data = devm_kzalloc(dev, sizeof(struct max31790_data), GFP_KERNEL);
492	if (!data)
493		return -ENOMEM;
494
495	data->client = client;
496	mutex_init(&data->update_lock);
497
498	/*
499	 * Initialize the max31790 chip
500	 */
501	err = max31790_init_client(client, data);
502	if (err)
503		return err;
504
505	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
506							 data,
507							 &max31790_chip_info,
508							 NULL);
509
510	return PTR_ERR_OR_ZERO(hwmon_dev);
511}
512
513static const struct i2c_device_id max31790_id[] = {
514	{ "max31790", 0 },
515	{ }
516};
517MODULE_DEVICE_TABLE(i2c, max31790_id);
518
519static struct i2c_driver max31790_driver = {
520	.class		= I2C_CLASS_HWMON,
521	.probe		= max31790_probe,
522	.driver = {
523		.name	= "max31790",
524	},
525	.id_table	= max31790_id,
526};
527
528module_i2c_driver(max31790_driver);
529
530MODULE_AUTHOR("Il Han <corone.il.han@gmail.com>");
531MODULE_DESCRIPTION("MAX31790 sensor driver");
532MODULE_LICENSE("GPL");