1/*
  2    Copyright (c) 2011 David George <david.george@ska.ac.za>
 
 
 
 
  3
  4    based on adm1021.c
  5    some credit to Christoph Scheurer, but largely a rewrite
  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    You should have received a copy of the GNU General Public License
 18    along with this program; if not, write to the Free Software
 19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 20*/
 21
 22#include <linux/module.h>
 23#include <linux/init.h>
 
 
 24#include <linux/slab.h>
 25#include <linux/jiffies.h>
 26#include <linux/i2c.h>
 27#include <linux/hwmon.h>
 28#include <linux/hwmon-sysfs.h>
 29#include <linux/err.h>
 30#include <linux/mutex.h>
 31
 32/* Addresses to scan */
 33static unsigned short max1668_addr_list[] = {
 34	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
 35
 36/* max1668 registers */
 37
 38#define MAX1668_REG_TEMP(nr)	(nr)
 39#define MAX1668_REG_STAT1	0x05
 40#define MAX1668_REG_STAT2	0x06
 41#define MAX1668_REG_MAN_ID	0xfe
 42#define MAX1668_REG_DEV_ID	0xff
 43
 44/* limits */
 45
 46/* write high limits */
 47#define MAX1668_REG_LIMH_WR(nr)	(0x13 + 2 * (nr))
 48/* write low limits */
 49#define MAX1668_REG_LIML_WR(nr)	(0x14 + 2 * (nr))
 50/* read high limits */
 51#define MAX1668_REG_LIMH_RD(nr)	(0x08 + 2 * (nr))
 52/* read low limits */
 53#define MAX1668_REG_LIML_RD(nr)	(0x09 + 2 * (nr))
 54
 55/* manufacturer and device ID Constants */
 56#define MAN_ID_MAXIM		0x4d
 57#define DEV_ID_MAX1668		0x3
 58#define DEV_ID_MAX1805		0x5
 59#define DEV_ID_MAX1989		0xb
 60
 61/* read only mode module parameter */
 62static int read_only;
 63module_param(read_only, bool, 0);
 64MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");
 65
 66enum chips { max1668, max1805, max1989 };
 67
 68struct max1668_data {
 69	struct device *hwmon_dev;
 70	enum chips type;
 71
 72	struct mutex update_lock;
 73	char valid;		/* !=0 if following fields are valid */
 74	unsigned long last_updated;	/* In jiffies */
 75
 76	/* 1x local and 4x remote */
 77	s8 temp_max[5];
 78	s8 temp_min[5];
 79	s8 temp[5];
 80	u16 alarms;
 81};
 82
 83static struct max1668_data *max1668_update_device(struct device *dev)
 
 84{
 85	struct i2c_client *client = to_i2c_client(dev);
 86	struct max1668_data *data = i2c_get_clientdata(client);
 87	struct max1668_data *ret = data;
 88	s32 val;
 89	int i;
 90
 91	mutex_lock(&data->update_lock);
 92
 93	if (data->valid && !time_after(jiffies,
 94			data->last_updated + HZ + HZ / 2))
 95		goto abort;
 96
 97	for (i = 0; i < 5; i++) {
 98		val = i2c_smbus_read_byte_data(client, MAX1668_REG_TEMP(i));
 99		if (unlikely(val < 0)) {
100			ret = ERR_PTR(val);
101			goto abort;
102		}
103		data->temp[i] = (s8) val;
104
105		val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIMH_RD(i));
106		if (unlikely(val < 0)) {
107			ret = ERR_PTR(val);
108			goto abort;
109		}
110		data->temp_max[i] = (s8) val;
111
112		val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIML_RD(i));
113		if (unlikely(val < 0)) {
114			ret = ERR_PTR(val);
115			goto abort;
116		}
117		data->temp_min[i] = (s8) val;
118	}
119
120	val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT1);
121	if (unlikely(val < 0)) {
122		ret = ERR_PTR(val);
123		goto abort;
124	}
125	data->alarms = val << 8;
126
127	val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT2);
128	if (unlikely(val < 0)) {
129		ret = ERR_PTR(val);
130		goto abort;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131	}
132	data->alarms |= val;
133
134	data->last_updated = jiffies;
135	data->valid = 1;
136abort:
137	mutex_unlock(&data->update_lock);
138
139	return ret;
140}
141
142static ssize_t show_temp(struct device *dev,
143			 struct device_attribute *devattr, char *buf)
144{
145	int index = to_sensor_dev_attr(devattr)->index;
146	struct max1668_data *data = max1668_update_device(dev);
147
148	if (IS_ERR(data))
149		return PTR_ERR(data);
150
151	return sprintf(buf, "%d\n", data->temp[index] * 1000);
152}
153
154static ssize_t show_temp_max(struct device *dev,
155			     struct device_attribute *devattr, char *buf)
156{
157	int index = to_sensor_dev_attr(devattr)->index;
158	struct max1668_data *data = max1668_update_device(dev);
159
160	if (IS_ERR(data))
161		return PTR_ERR(data);
162
163	return sprintf(buf, "%d\n", data->temp_max[index] * 1000);
164}
165
166static ssize_t show_temp_min(struct device *dev,
167			     struct device_attribute *devattr, char *buf)
168{
169	int index = to_sensor_dev_attr(devattr)->index;
170	struct max1668_data *data = max1668_update_device(dev);
171
172	if (IS_ERR(data))
173		return PTR_ERR(data);
174
175	return sprintf(buf, "%d\n", data->temp_min[index] * 1000);
176}
177
178static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
179			  char *buf)
180{
181	int index = to_sensor_dev_attr(attr)->index;
182	struct max1668_data *data = max1668_update_device(dev);
183
184	if (IS_ERR(data))
185		return PTR_ERR(data);
186
187	return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
188}
189
190static ssize_t show_fault(struct device *dev,
191			  struct device_attribute *devattr, char *buf)
192{
193	int index = to_sensor_dev_attr(devattr)->index;
194	struct max1668_data *data = max1668_update_device(dev);
195
196	if (IS_ERR(data))
197		return PTR_ERR(data);
198
199	return sprintf(buf, "%u\n",
200		       (data->alarms & (1 << 12)) && data->temp[index] == 127);
201}
202
203static ssize_t set_temp_max(struct device *dev,
204			    struct device_attribute *devattr,
205			    const char *buf, size_t count)
206{
207	int index = to_sensor_dev_attr(devattr)->index;
208	struct i2c_client *client = to_i2c_client(dev);
209	struct max1668_data *data = i2c_get_clientdata(client);
210	long temp;
211	int ret;
212
213	ret = kstrtol(buf, 10, &temp);
214	if (ret < 0)
215		return ret;
216
217	mutex_lock(&data->update_lock);
218	data->temp_max[index] = SENSORS_LIMIT(temp/1000, -128, 127);
219	if (i2c_smbus_write_byte_data(client,
220					MAX1668_REG_LIMH_WR(index),
221					data->temp_max[index]))
222		count = -EIO;
223	mutex_unlock(&data->update_lock);
224
225	return count;
226}
227
228static ssize_t set_temp_min(struct device *dev,
229			    struct device_attribute *devattr,
230			    const char *buf, size_t count)
231{
232	int index = to_sensor_dev_attr(devattr)->index;
233	struct i2c_client *client = to_i2c_client(dev);
234	struct max1668_data *data = i2c_get_clientdata(client);
235	long temp;
236	int ret;
237
238	ret = kstrtol(buf, 10, &temp);
239	if (ret < 0)
240		return ret;
241
242	mutex_lock(&data->update_lock);
243	data->temp_min[index] = SENSORS_LIMIT(temp/1000, -128, 127);
244	if (i2c_smbus_write_byte_data(client,
245					MAX1668_REG_LIML_WR(index),
246					data->temp_max[index]))
247		count = -EIO;
248	mutex_unlock(&data->update_lock);
249
250	return count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
251}
252
253static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
254static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max,
255				set_temp_max, 0);
256static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp_min,
257				set_temp_min, 0);
258static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
259static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO, show_temp_max,
260				set_temp_max, 1);
261static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO, show_temp_min,
262				set_temp_min, 1);
263static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
264static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO, show_temp_max,
265				set_temp_max, 2);
266static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO, show_temp_min,
267				set_temp_min, 2);
268static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
269static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO, show_temp_max,
270				set_temp_max, 3);
271static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO, show_temp_min,
272				set_temp_min, 3);
273static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO, show_temp, NULL, 4);
274static SENSOR_DEVICE_ATTR(temp5_max, S_IRUGO, show_temp_max,
275				set_temp_max, 4);
276static SENSOR_DEVICE_ATTR(temp5_min, S_IRUGO, show_temp_min,
277				set_temp_min, 4);
278
279static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 14);
280static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 13);
281static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 7);
282static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 6);
283static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_alarm, NULL, 5);
284static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
285static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_alarm, NULL, 3);
286static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 2);
287static SENSOR_DEVICE_ATTR(temp5_min_alarm, S_IRUGO, show_alarm, NULL, 1);
288static SENSOR_DEVICE_ATTR(temp5_max_alarm, S_IRUGO, show_alarm, NULL, 0);
289
290static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
291static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
292static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
293static SENSOR_DEVICE_ATTR(temp5_fault, S_IRUGO, show_fault, NULL, 4);
294
295/* Attributes common to MAX1668, MAX1989 and MAX1805 */
296static struct attribute *max1668_attribute_common[] = {
297	&sensor_dev_attr_temp1_max.dev_attr.attr,
298	&sensor_dev_attr_temp1_min.dev_attr.attr,
299	&sensor_dev_attr_temp1_input.dev_attr.attr,
300	&sensor_dev_attr_temp2_max.dev_attr.attr,
301	&sensor_dev_attr_temp2_min.dev_attr.attr,
302	&sensor_dev_attr_temp2_input.dev_attr.attr,
303	&sensor_dev_attr_temp3_max.dev_attr.attr,
304	&sensor_dev_attr_temp3_min.dev_attr.attr,
305	&sensor_dev_attr_temp3_input.dev_attr.attr,
306
307	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
308	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
309	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
310	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
311	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
312	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
313
314	&sensor_dev_attr_temp2_fault.dev_attr.attr,
315	&sensor_dev_attr_temp3_fault.dev_attr.attr,
316	NULL
317};
318
319/* Attributes not present on MAX1805 */
320static struct attribute *max1668_attribute_unique[] = {
321	&sensor_dev_attr_temp4_max.dev_attr.attr,
322	&sensor_dev_attr_temp4_min.dev_attr.attr,
323	&sensor_dev_attr_temp4_input.dev_attr.attr,
324	&sensor_dev_attr_temp5_max.dev_attr.attr,
325	&sensor_dev_attr_temp5_min.dev_attr.attr,
326	&sensor_dev_attr_temp5_input.dev_attr.attr,
327
328	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
329	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
330	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
331	&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
332
333	&sensor_dev_attr_temp4_fault.dev_attr.attr,
334	&sensor_dev_attr_temp5_fault.dev_attr.attr,
335	NULL
336};
337
338static mode_t max1668_attribute_mode(struct kobject *kobj,
339				     struct attribute *attr, int index)
340{
341	int ret = S_IRUGO;
342	if (read_only)
343		return ret;
344	if (attr == &sensor_dev_attr_temp1_max.dev_attr.attr ||
345	    attr == &sensor_dev_attr_temp2_max.dev_attr.attr ||
346	    attr == &sensor_dev_attr_temp3_max.dev_attr.attr ||
347	    attr == &sensor_dev_attr_temp4_max.dev_attr.attr ||
348	    attr == &sensor_dev_attr_temp5_max.dev_attr.attr ||
349	    attr == &sensor_dev_attr_temp1_min.dev_attr.attr ||
350	    attr == &sensor_dev_attr_temp2_min.dev_attr.attr ||
351	    attr == &sensor_dev_attr_temp3_min.dev_attr.attr ||
352	    attr == &sensor_dev_attr_temp4_min.dev_attr.attr ||
353	    attr == &sensor_dev_attr_temp5_min.dev_attr.attr)
354		ret |= S_IWUSR;
355	return ret;
356}
357
358static const struct attribute_group max1668_group_common = {
359	.attrs = max1668_attribute_common,
360	.is_visible = max1668_attribute_mode
361};
362
363static const struct attribute_group max1668_group_unique = {
364	.attrs = max1668_attribute_unique,
365	.is_visible = max1668_attribute_mode
366};
367
368/* Return 0 if detection is successful, -ENODEV otherwise */
369static int max1668_detect(struct i2c_client *client,
370			  struct i2c_board_info *info)
371{
372	struct i2c_adapter *adapter = client->adapter;
373	const char *type_name;
374	int man_id, dev_id;
375
376	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
377		return -ENODEV;
378
379	/* Check for unsupported part */
380	man_id = i2c_smbus_read_byte_data(client, MAX1668_REG_MAN_ID);
381	if (man_id != MAN_ID_MAXIM)
382		return -ENODEV;
383
384	dev_id = i2c_smbus_read_byte_data(client, MAX1668_REG_DEV_ID);
385	if (dev_id < 0)
386		return -ENODEV;
387
388	type_name = NULL;
389	if (dev_id == DEV_ID_MAX1668)
390		type_name = "max1668";
391	else if (dev_id == DEV_ID_MAX1805)
392		type_name = "max1805";
393	else if (dev_id == DEV_ID_MAX1989)
394		type_name = "max1989";
395
396	if (!type_name)
397		return -ENODEV;
398
399	strlcpy(info->type, type_name, I2C_NAME_SIZE);
400
401	return 0;
402}
403
404static int max1668_probe(struct i2c_client *client,
405			 const struct i2c_device_id *id)
406{
407	struct i2c_adapter *adapter = client->adapter;
408	struct max1668_data *data;
409	int err;
410
411	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
412		return -ENODEV;
 
413
414	data = kzalloc(sizeof(struct max1668_data), GFP_KERNEL);
415	if (!data)
416		return -ENOMEM;
417
418	i2c_set_clientdata(client, data);
419	data->type = id->driver_data;
420	mutex_init(&data->update_lock);
421
422	/* Register sysfs hooks */
423	err = sysfs_create_group(&client->dev.kobj, &max1668_group_common);
424	if (err)
425		goto error_free;
426
427	if (data->type == max1668 || data->type == max1989) {
428		err = sysfs_create_group(&client->dev.kobj,
429					 &max1668_group_unique);
430		if (err)
431			goto error_sysrem0;
432	}
433
434	data->hwmon_dev = hwmon_device_register(&client->dev);
435	if (IS_ERR(data->hwmon_dev)) {
436		err = PTR_ERR(data->hwmon_dev);
437		goto error_sysrem1;
438	}
439
440	return 0;
 
 
 
441
442error_sysrem1:
443	if (data->type == max1668 || data->type == max1989)
444		sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
445error_sysrem0:
446	sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
447error_free:
448	kfree(data);
449	return err;
450}
451
452static int max1668_remove(struct i2c_client *client)
 
 
 
 
 
 
 
 
 
 
 
 
 
453{
454	struct max1668_data *data = i2c_get_clientdata(client);
 
 
 
455
456	hwmon_device_unregister(data->hwmon_dev);
457	if (data->type == max1668 || data->type == max1989)
458		sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
459
460	sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
 
 
461
462	kfree(data);
463	return 0;
 
 
 
 
 
 
 
 
464}
465
466static const struct i2c_device_id max1668_id[] = {
467	{ "max1668", max1668 },
468	{ "max1805", max1805 },
469	{ "max1989", max1989 },
470	{ }
471};
472MODULE_DEVICE_TABLE(i2c, max1668_id);
473
474/* This is the driver that will be inserted */
475static struct i2c_driver max1668_driver = {
476	.class = I2C_CLASS_HWMON,
477	.driver = {
478		  .name	= "max1668",
479		  },
480	.probe = max1668_probe,
481	.remove	= max1668_remove,
482	.id_table = max1668_id,
483	.detect	= max1668_detect,
484	.address_list = max1668_addr_list,
485};
486
487static int __init sensors_max1668_init(void)
488{
489	return i2c_add_driver(&max1668_driver);
490}
491
492static void __exit sensors_max1668_exit(void)
493{
494	i2c_del_driver(&max1668_driver);
495}
496
497MODULE_AUTHOR("David George <david.george@ska.ac.za>");
498MODULE_DESCRIPTION("MAX1668 remote temperature sensor driver");
499MODULE_LICENSE("GPL");
500
501module_init(sensors_max1668_init)
502module_exit(sensors_max1668_exit)

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (c) 2011 David George <david.george@ska.ac.za>
  4 *
  5 * based on adm1021.c
  6 * some credit to Christoph Scheurer, but largely a rewrite
  7 */
  8
  9#include <linux/bitops.h>
 10#include <linux/bits.h>
 11#include <linux/err.h>
 12#include <linux/hwmon.h>
 13#include <linux/i2c.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 14#include <linux/init.h>
 15#include <linux/module.h>
 16#include <linux/regmap.h>
 17#include <linux/slab.h>
 
 
 
 
 
 
 18
 19/* Addresses to scan */
 20static const unsigned short max1668_addr_list[] = {
 21	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
 22
 23/* max1668 registers */
 24
 25#define MAX1668_REG_TEMP(nr)	(nr)
 26#define MAX1668_REG_STAT1	0x05
 27#define MAX1668_REG_STAT2	0x06
 28#define MAX1668_REG_MAN_ID	0xfe
 29#define MAX1668_REG_DEV_ID	0xff
 30
 31/* limits */
 32
 33/* high limits */
 34#define MAX1668_REG_LIMH(nr)	(0x08 + 2 * (nr))
 
 
 
 
 35/* read low limits */
 36#define MAX1668_REG_LIML(nr)	(0x09 + 2 * (nr))
 37
 38/* manufacturer and device ID Constants */
 39#define MAN_ID_MAXIM		0x4d
 40#define DEV_ID_MAX1668		0x3
 41#define DEV_ID_MAX1805		0x5
 42#define DEV_ID_MAX1989		0xb
 43
 44/* read only mode module parameter */
 45static bool read_only;
 46module_param(read_only, bool, 0);
 47MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");
 48
 
 
 49struct max1668_data {
 50	struct regmap *regmap;
 51	int channels;
 
 
 
 
 
 
 
 
 
 
 52};
 53
 54static int max1668_read(struct device *dev, enum hwmon_sensor_types type,
 55			u32 attr, int channel, long *val)
 56{
 57	struct max1668_data *data = dev_get_drvdata(dev);
 58	struct regmap *regmap = data->regmap;
 59	u32 regs[2] = { MAX1668_REG_STAT1, MAX1668_REG_TEMP(channel) };
 60	u8 regvals[2];
 61	u32 regval;
 62	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 63
 64	switch (attr) {
 65	case hwmon_temp_input:
 66		ret = regmap_read(regmap, MAX1668_REG_TEMP(channel), &regval);
 67		if (ret)
 68			return ret;
 69		*val = sign_extend32(regval, 7) * 1000;
 70		break;
 71	case hwmon_temp_min:
 72		ret = regmap_read(regmap, MAX1668_REG_LIML(channel), &regval);
 73		if (ret)
 74			return ret;
 75		*val = sign_extend32(regval, 7) * 1000;
 76		break;
 77	case hwmon_temp_max:
 78		ret = regmap_read(regmap, MAX1668_REG_LIMH(channel), &regval);
 79		if (ret)
 80			return ret;
 81		*val = sign_extend32(regval, 7) * 1000;
 82		break;
 83	case hwmon_temp_min_alarm:
 84		ret = regmap_read(regmap,
 85				  channel ? MAX1668_REG_STAT2 : MAX1668_REG_STAT1,
 86				  &regval);
 87		if (ret)
 88			return ret;
 89		if (channel)
 90			*val = !!(regval & BIT(9 - channel * 2));
 91		else
 92			*val = !!(regval & BIT(5));
 93		break;
 94	case hwmon_temp_max_alarm:
 95		ret = regmap_read(regmap,
 96				  channel ? MAX1668_REG_STAT2 : MAX1668_REG_STAT1,
 97				  &regval);
 98		if (ret)
 99			return ret;
100		if (channel)
101			*val = !!(regval & BIT(8 - channel * 2));
102		else
103			*val = !!(regval & BIT(6));
104		break;
105	case hwmon_temp_fault:
106		ret = regmap_multi_reg_read(regmap, regs, regvals, 2);
107		if (ret)
108			return ret;
109		*val = !!((regvals[0] & BIT(4)) && regvals[1] == 127);
110		break;
111	default:
112		return -EOPNOTSUPP;
113	}
114	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115}
116
117static int max1668_write(struct device *dev, enum hwmon_sensor_types type,
118			 u32 attr, int channel, long val)
119{
120	struct max1668_data *data = dev_get_drvdata(dev);
121	struct regmap *regmap = data->regmap;
 
 
 
122
123	val = clamp_val(val / 1000, -128, 127);
 
 
124
125	switch (attr) {
126	case hwmon_temp_min:
127		return regmap_write(regmap, MAX1668_REG_LIML(channel), val);
128	case hwmon_temp_max:
129		return regmap_write(regmap, MAX1668_REG_LIMH(channel), val);
130	default:
131		return -EOPNOTSUPP;
132	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
133}
134
135static umode_t max1668_is_visible(const void *_data, enum hwmon_sensor_types type,
136				  u32 attr, int channel)
 
137{
138	const struct max1668_data *data = _data;
 
 
 
 
 
 
 
 
139
140	if (channel >= data->channels)
141		return 0;
 
 
 
 
 
142
143	switch (attr) {
144	case hwmon_temp_min:
145	case hwmon_temp_max:
146		return read_only ? 0444 : 0644;
147	case hwmon_temp_input:
148	case hwmon_temp_min_alarm:
149	case hwmon_temp_max_alarm:
150		return 0444;
151	case hwmon_temp_fault:
152		if (channel)
153			return 0444;
154		break;
155	default:
156		break;
157	}
158	return 0;
159}
160
161static const struct hwmon_channel_info * const max1668_info[] = {
162	HWMON_CHANNEL_INFO(temp,
163			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
164			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM,
165			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
166			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
167			   HWMON_T_FAULT,
168			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
169			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
170			   HWMON_T_FAULT,
171			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
172			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
173			   HWMON_T_FAULT,
174			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
175			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
176			   HWMON_T_FAULT),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
177	NULL
178};
179
180static const struct hwmon_ops max1668_hwmon_ops = {
181	.is_visible = max1668_is_visible,
182	.read = max1668_read,
183	.write = max1668_write,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
184};
185
186static const struct hwmon_chip_info max1668_chip_info = {
187	.ops = &max1668_hwmon_ops,
188	.info = max1668_info,
189};
190
191/* Return 0 if detection is successful, -ENODEV otherwise */
192static int max1668_detect(struct i2c_client *client,
193			  struct i2c_board_info *info)
194{
195	struct i2c_adapter *adapter = client->adapter;
196	const char *type_name;
197	int man_id, dev_id;
198
199	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
200		return -ENODEV;
201
202	/* Check for unsupported part */
203	man_id = i2c_smbus_read_byte_data(client, MAX1668_REG_MAN_ID);
204	if (man_id != MAN_ID_MAXIM)
205		return -ENODEV;
206
207	dev_id = i2c_smbus_read_byte_data(client, MAX1668_REG_DEV_ID);
208	if (dev_id < 0)
209		return -ENODEV;
210
211	type_name = NULL;
212	if (dev_id == DEV_ID_MAX1668)
213		type_name = "max1668";
214	else if (dev_id == DEV_ID_MAX1805)
215		type_name = "max1805";
216	else if (dev_id == DEV_ID_MAX1989)
217		type_name = "max1989";
218
219	if (!type_name)
220		return -ENODEV;
221
222	strscpy(info->type, type_name, I2C_NAME_SIZE);
223
224	return 0;
225}
226
227/* regmap */
 
 
 
 
 
228
229static int max1668_reg_read(void *context, unsigned int reg, unsigned int *val)
230{
231	int ret;
232
233	ret = i2c_smbus_read_byte_data(context, reg);
234	if (ret < 0)
235		return ret;
236
237	*val = ret;
238	return 0;
239}
 
 
 
 
 
 
 
 
 
 
 
 
240
241static int max1668_reg_write(void *context, unsigned int reg, unsigned int val)
242{
243	return i2c_smbus_write_byte_data(context, reg + 11, val);
244}
 
245
246static bool max1668_regmap_is_volatile(struct device *dev, unsigned int reg)
247{
248	return reg <= MAX1668_REG_STAT2;
249}
250
251static bool max1668_regmap_is_writeable(struct device *dev, unsigned int reg)
252{
253	return reg > MAX1668_REG_STAT2 && reg <= MAX1668_REG_LIML(4);
 
 
 
 
 
254}
255
256static const struct regmap_config max1668_regmap_config = {
257	.reg_bits = 8,
258	.val_bits = 8,
259	.cache_type = REGCACHE_MAPLE,
260	.volatile_reg = max1668_regmap_is_volatile,
261	.writeable_reg = max1668_regmap_is_writeable,
262};
263
264static const struct regmap_bus max1668_regmap_bus = {
265	.reg_write = max1668_reg_write,
266	.reg_read = max1668_reg_read,
267};
268
269static int max1668_probe(struct i2c_client *client)
270{
271	struct i2c_adapter *adapter = client->adapter;
272	struct device *dev = &client->dev;
273	struct device *hwmon_dev;
274	struct max1668_data *data;
275
276	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
277		return -ENODEV;
 
278
279	data = devm_kzalloc(dev, sizeof(struct max1668_data), GFP_KERNEL);
280	if (!data)
281		return -ENOMEM;
282
283	data->regmap = devm_regmap_init(dev, &max1668_regmap_bus, client,
284					&max1668_regmap_config);
285	if (IS_ERR(data->regmap))
286		return PTR_ERR(data->regmap);
287
288	data->channels = (uintptr_t)i2c_get_match_data(client);
289
290	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
291							 &max1668_chip_info, NULL);
292	return PTR_ERR_OR_ZERO(hwmon_dev);
293}
294
295static const struct i2c_device_id max1668_id[] = {
296	{ "max1668", 5 },
297	{ "max1805", 3 },
298	{ "max1989", 5 },
299	{ }
300};
301MODULE_DEVICE_TABLE(i2c, max1668_id);
302
303/* This is the driver that will be inserted */
304static struct i2c_driver max1668_driver = {
305	.class = I2C_CLASS_HWMON,
306	.driver = {
307		  .name	= "max1668",
308		  },
309	.probe = max1668_probe,
 
310	.id_table = max1668_id,
311	.detect	= max1668_detect,
312	.address_list = max1668_addr_list,
313};
314
315module_i2c_driver(max1668_driver);
 
 
 
 
 
 
 
 
316
317MODULE_AUTHOR("David George <david.george@ska.ac.za>");
318MODULE_DESCRIPTION("MAX1668 remote temperature sensor driver");
319MODULE_LICENSE("GPL");