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v3.15
  1/*
  2 * ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
  3 *	      monitoring
  4 * Christian W. Zuckschwerdt  <zany@triq.net>  2000-11-23
  5 * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
  6 * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
  7 * the help of Jean Delvare <jdelvare@suse.de>
  8 *
  9 * The DS1621 device is a digital temperature/thermometer with 9-bit
 10 * resolution, a thermal alarm output (Tout), and user-defined minimum
 11 * and maximum temperature thresholds (TH and TL).
 12 *
 13 * The DS1625, DS1631, DS1721, and DS1731 are pin compatible with the DS1621
 14 * and similar in operation, with slight variations as noted in the device
 15 * datasheets (please refer to www.maximintegrated.com for specific
 16 * device information).
 17 *
 18 * Since the DS1621 was the first chipset supported by this driver,
 19 * most comments will refer to this chipset, but are actually general
 20 * and concern all supported chipsets, unless mentioned otherwise.
 21 *
 22 * This program is free software; you can redistribute it and/or modify
 23 * it under the terms of the GNU General Public License as published by
 24 * the Free Software Foundation; either version 2 of the License, or
 25 * (at your option) any later version.
 26 *
 27 * This program is distributed in the hope that it will be useful,
 28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 30 * GNU General Public License for more details.
 31 *
 32 * You should have received a copy of the GNU General Public License
 33 * along with this program; if not, write to the Free Software
 34 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 35 */
 36
 37#include <linux/module.h>
 38#include <linux/init.h>
 39#include <linux/slab.h>
 40#include <linux/jiffies.h>
 41#include <linux/i2c.h>
 42#include <linux/hwmon.h>
 43#include <linux/hwmon-sysfs.h>
 44#include <linux/err.h>
 45#include <linux/mutex.h>
 46#include <linux/sysfs.h>
 47#include <linux/kernel.h>
 48
 49/* Supported devices */
 50enum chips { ds1621, ds1625, ds1631, ds1721, ds1731 };
 51
 52/* Insmod parameters */
 53static int polarity = -1;
 54module_param(polarity, int, 0);
 55MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low");
 56
 57/*
 58 * The Configuration/Status register
 59 *
 60 * - DS1621:
 61 *   7    6    5    4    3    2    1    0
 62 * |Done|THF |TLF |NVB | X  | X  |POL |1SHOT|
 63 *
 64 * - DS1625:
 65 *   7    6    5    4    3    2    1    0
 66 * |Done|THF |TLF |NVB | 1  | 0  |POL |1SHOT|
 67 *
 68 * - DS1631, DS1731:
 69 *   7    6    5    4    3    2    1    0
 70 * |Done|THF |TLF |NVB | R1 | R0 |POL |1SHOT|
 71 *
 72 * - DS1721:
 73 *   7    6    5    4    3    2    1    0
 74 * |Done| X  | X  | U  | R1 | R0 |POL |1SHOT|
 75 *
 76 * Where:
 77 * - 'X' is Reserved
 78 * - 'U' is Undefined
 79 */
 80#define DS1621_REG_CONFIG_NVB		0x10
 81#define DS1621_REG_CONFIG_RESOL		0x0C
 82#define DS1621_REG_CONFIG_POLARITY	0x02
 83#define DS1621_REG_CONFIG_1SHOT		0x01
 84#define DS1621_REG_CONFIG_DONE		0x80
 85
 86#define DS1621_REG_CONFIG_RESOL_SHIFT	2
 87
 88/* ds1721 conversion rates: {C/LSB, time(ms), resolution bit setting} */
 89static const unsigned short ds1721_convrates[] = {
 90	94,	/*  9-bits (0.5,  93.75, RES[0..1] = 0 */
 91	188,	/* 10-bits (0.25, 187.5, RES[0..1] = 1 */
 92	375,	/* 11-bits (0.125,  375, RES[0..1] = 2 */
 93	750,	/* 12-bits (0.0625, 750, RES[0..1] = 3 */
 94};
 95
 96#define DS1621_CONVERSION_MAX	750
 97#define DS1625_CONVERSION_MAX	500
 98
 99#define DS1621_TEMP_MAX	125000
100#define DS1621_TEMP_MIN	(-55000)
101
102/* The DS1621 temperature registers */
103static const u8 DS1621_REG_TEMP[3] = {
104	0xAA,		/* input, word, RO */
105	0xA2,		/* min, word, RW */
106	0xA1,		/* max, word, RW */
107};
108#define DS1621_REG_CONF			0xAC /* byte, RW */
109#define DS1621_COM_START		0xEE /* no data */
110#define DS1721_COM_START		0x51 /* no data */
111#define DS1621_COM_STOP			0x22 /* no data */
112
113/* The DS1621 configuration register */
114#define DS1621_ALARM_TEMP_HIGH		0x40
115#define DS1621_ALARM_TEMP_LOW		0x20
116
117/* Conversions */
118#define ALARMS_FROM_REG(val) ((val) & \
119			(DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))
120
121/* Each client has this additional data */
122struct ds1621_data {
123	struct i2c_client *client;
124	struct mutex update_lock;
125	char valid;			/* !=0 if following fields are valid */
126	unsigned long last_updated;	/* In jiffies */
127	enum chips kind;		/* device type */
128
129	u16 temp[3];			/* Register values, word */
130	u8 conf;			/* Register encoding, combined */
131	u8 zbits;			/* Resolution encoded as number of
132					 * zero bits */
133	u16 update_interval;		/* Conversion rate in milliseconds */
134};
135
136static inline int DS1621_TEMP_FROM_REG(u16 reg)
137{
138	return DIV_ROUND_CLOSEST(((s16)reg / 16) * 625, 10);
139}
140
141/*
142 * TEMP: 0.001C/bit (-55C to +125C)
143 * REG:
144 *  - 1621, 1625: 0.5C/bit, 7 zero-bits
145 *  - 1631, 1721, 1731: 0.0625C/bit, 4 zero-bits
146 */
147static inline u16 DS1621_TEMP_TO_REG(long temp, u8 zbits)
148{
149	temp = clamp_val(temp, DS1621_TEMP_MIN, DS1621_TEMP_MAX);
150	temp = DIV_ROUND_CLOSEST(temp * (1 << (8 - zbits)), 1000) << zbits;
151	return temp;
152}
153
154static void ds1621_init_client(struct ds1621_data *data,
155			       struct i2c_client *client)
156{
157	u8 conf, new_conf, sreg, resol;
158
159	new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
160	/* switch to continuous conversion mode */
161	new_conf &= ~DS1621_REG_CONFIG_1SHOT;
162
163	/* setup output polarity */
164	if (polarity == 0)
165		new_conf &= ~DS1621_REG_CONFIG_POLARITY;
166	else if (polarity == 1)
167		new_conf |= DS1621_REG_CONFIG_POLARITY;
168
169	if (conf != new_conf)
170		i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf);
171
172	switch (data->kind) {
173	case ds1625:
174		data->update_interval = DS1625_CONVERSION_MAX;
175		data->zbits = 7;
176		sreg = DS1621_COM_START;
177		break;
178	case ds1631:
179	case ds1721:
180	case ds1731:
181		resol = (new_conf & DS1621_REG_CONFIG_RESOL) >>
182			 DS1621_REG_CONFIG_RESOL_SHIFT;
183		data->update_interval = ds1721_convrates[resol];
184		data->zbits = 7 - resol;
185		sreg = DS1721_COM_START;
186		break;
187	default:
188		data->update_interval = DS1621_CONVERSION_MAX;
189		data->zbits = 7;
190		sreg = DS1621_COM_START;
191		break;
192	}
193
194	/* start conversion */
195	i2c_smbus_write_byte(client, sreg);
196}
197
198static struct ds1621_data *ds1621_update_client(struct device *dev)
199{
200	struct ds1621_data *data = dev_get_drvdata(dev);
201	struct i2c_client *client = data->client;
202	u8 new_conf;
203
204	mutex_lock(&data->update_lock);
205
206	if (time_after(jiffies, data->last_updated + data->update_interval) ||
207	    !data->valid) {
208		int i;
209
210		dev_dbg(&client->dev, "Starting ds1621 update\n");
211
212		data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
213
214		for (i = 0; i < ARRAY_SIZE(data->temp); i++)
215			data->temp[i] = i2c_smbus_read_word_swapped(client,
216							 DS1621_REG_TEMP[i]);
217
218		/* reset alarms if necessary */
219		new_conf = data->conf;
220		if (data->temp[0] > data->temp[1])	/* input > min */
221			new_conf &= ~DS1621_ALARM_TEMP_LOW;
222		if (data->temp[0] < data->temp[2])	/* input < max */
223			new_conf &= ~DS1621_ALARM_TEMP_HIGH;
224		if (data->conf != new_conf)
225			i2c_smbus_write_byte_data(client, DS1621_REG_CONF,
226						  new_conf);
227
228		data->last_updated = jiffies;
229		data->valid = 1;
230	}
231
232	mutex_unlock(&data->update_lock);
233
234	return data;
235}
236
237static ssize_t show_temp(struct device *dev, struct device_attribute *da,
238			 char *buf)
239{
240	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
241	struct ds1621_data *data = ds1621_update_client(dev);
242	return sprintf(buf, "%d\n",
243		       DS1621_TEMP_FROM_REG(data->temp[attr->index]));
244}
245
246static ssize_t set_temp(struct device *dev, struct device_attribute *da,
247			const char *buf, size_t count)
248{
249	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
250	struct ds1621_data *data = dev_get_drvdata(dev);
251	long val;
252	int err;
253
254	err = kstrtol(buf, 10, &val);
255	if (err)
256		return err;
257
258	mutex_lock(&data->update_lock);
259	data->temp[attr->index] = DS1621_TEMP_TO_REG(val, data->zbits);
260	i2c_smbus_write_word_swapped(data->client, DS1621_REG_TEMP[attr->index],
261				     data->temp[attr->index]);
262	mutex_unlock(&data->update_lock);
263	return count;
264}
265
266static ssize_t show_alarms(struct device *dev, struct device_attribute *da,
267			   char *buf)
268{
269	struct ds1621_data *data = ds1621_update_client(dev);
270	return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf));
271}
272
273static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
274			  char *buf)
275{
276	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
277	struct ds1621_data *data = ds1621_update_client(dev);
278	return sprintf(buf, "%d\n", !!(data->conf & attr->index));
279}
280
281static ssize_t show_convrate(struct device *dev, struct device_attribute *da,
282			  char *buf)
283{
284	struct ds1621_data *data = dev_get_drvdata(dev);
285	return scnprintf(buf, PAGE_SIZE, "%hu\n", data->update_interval);
286}
287
288static ssize_t set_convrate(struct device *dev, struct device_attribute *da,
289			    const char *buf, size_t count)
290{
291	struct ds1621_data *data = dev_get_drvdata(dev);
292	struct i2c_client *client = data->client;
293	unsigned long convrate;
294	s32 err;
295	int resol = 0;
296
297	err = kstrtoul(buf, 10, &convrate);
298	if (err)
299		return err;
300
301	/* Convert rate into resolution bits */
302	while (resol < (ARRAY_SIZE(ds1721_convrates) - 1) &&
303	       convrate > ds1721_convrates[resol])
304		resol++;
305
306	mutex_lock(&data->update_lock);
307	data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
308	data->conf &= ~DS1621_REG_CONFIG_RESOL;
309	data->conf |= (resol << DS1621_REG_CONFIG_RESOL_SHIFT);
310	i2c_smbus_write_byte_data(client, DS1621_REG_CONF, data->conf);
311	data->update_interval = ds1721_convrates[resol];
 
312	mutex_unlock(&data->update_lock);
313
314	return count;
315}
316
317static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
318static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_convrate,
319		   set_convrate);
320
321static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
322static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1);
323static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2);
324static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
325		DS1621_ALARM_TEMP_LOW);
326static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
327		DS1621_ALARM_TEMP_HIGH);
328
329static struct attribute *ds1621_attributes[] = {
330	&sensor_dev_attr_temp1_input.dev_attr.attr,
331	&sensor_dev_attr_temp1_min.dev_attr.attr,
332	&sensor_dev_attr_temp1_max.dev_attr.attr,
333	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
334	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
335	&dev_attr_alarms.attr,
336	&dev_attr_update_interval.attr,
337	NULL
338};
339
340static umode_t ds1621_attribute_visible(struct kobject *kobj,
341					struct attribute *attr, int index)
342{
343	struct device *dev = container_of(kobj, struct device, kobj);
344	struct ds1621_data *data = dev_get_drvdata(dev);
345
346	if (attr == &dev_attr_update_interval.attr)
347		if (data->kind == ds1621 || data->kind == ds1625)
348			/* shhh, we're hiding update_interval */
349			return 0;
350	return attr->mode;
351}
352
353static const struct attribute_group ds1621_group = {
354	.attrs = ds1621_attributes,
355	.is_visible = ds1621_attribute_visible
356};
357__ATTRIBUTE_GROUPS(ds1621);
358
359static int ds1621_probe(struct i2c_client *client,
360			const struct i2c_device_id *id)
361{
362	struct ds1621_data *data;
363	struct device *hwmon_dev;
364
365	data = devm_kzalloc(&client->dev, sizeof(struct ds1621_data),
366			    GFP_KERNEL);
367	if (!data)
368		return -ENOMEM;
369
370	mutex_init(&data->update_lock);
371
372	data->kind = id->driver_data;
373	data->client = client;
374
375	/* Initialize the DS1621 chip */
376	ds1621_init_client(data, client);
377
378	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
379							   client->name, data,
380							   ds1621_groups);
381	return PTR_ERR_OR_ZERO(hwmon_dev);
382}
383
384static const struct i2c_device_id ds1621_id[] = {
385	{ "ds1621", ds1621 },
386	{ "ds1625", ds1625 },
387	{ "ds1631", ds1631 },
388	{ "ds1721", ds1721 },
389	{ "ds1731", ds1731 },
390	{ }
391};
392MODULE_DEVICE_TABLE(i2c, ds1621_id);
393
394/* This is the driver that will be inserted */
395static struct i2c_driver ds1621_driver = {
396	.class		= I2C_CLASS_HWMON,
397	.driver = {
398		.name	= "ds1621",
399	},
400	.probe		= ds1621_probe,
401	.id_table	= ds1621_id,
402};
403
404module_i2c_driver(ds1621_driver);
405
406MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>");
407MODULE_DESCRIPTION("DS1621 driver");
408MODULE_LICENSE("GPL");
v4.6
  1/*
  2 * ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
  3 *	      monitoring
  4 * Christian W. Zuckschwerdt  <zany@triq.net>  2000-11-23
  5 * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
  6 * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
  7 * the help of Jean Delvare <jdelvare@suse.de>
  8 *
  9 * The DS1621 device is a digital temperature/thermometer with 9-bit
 10 * resolution, a thermal alarm output (Tout), and user-defined minimum
 11 * and maximum temperature thresholds (TH and TL).
 12 *
 13 * The DS1625, DS1631, DS1721, and DS1731 are pin compatible with the DS1621
 14 * and similar in operation, with slight variations as noted in the device
 15 * datasheets (please refer to www.maximintegrated.com for specific
 16 * device information).
 17 *
 18 * Since the DS1621 was the first chipset supported by this driver,
 19 * most comments will refer to this chipset, but are actually general
 20 * and concern all supported chipsets, unless mentioned otherwise.
 21 *
 22 * This program is free software; you can redistribute it and/or modify
 23 * it under the terms of the GNU General Public License as published by
 24 * the Free Software Foundation; either version 2 of the License, or
 25 * (at your option) any later version.
 26 *
 27 * This program is distributed in the hope that it will be useful,
 28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 30 * GNU General Public License for more details.
 31 *
 32 * You should have received a copy of the GNU General Public License
 33 * along with this program; if not, write to the Free Software
 34 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 35 */
 36
 37#include <linux/module.h>
 38#include <linux/init.h>
 39#include <linux/slab.h>
 40#include <linux/jiffies.h>
 41#include <linux/i2c.h>
 42#include <linux/hwmon.h>
 43#include <linux/hwmon-sysfs.h>
 44#include <linux/err.h>
 45#include <linux/mutex.h>
 46#include <linux/sysfs.h>
 47#include <linux/kernel.h>
 48
 49/* Supported devices */
 50enum chips { ds1621, ds1625, ds1631, ds1721, ds1731 };
 51
 52/* Insmod parameters */
 53static int polarity = -1;
 54module_param(polarity, int, 0);
 55MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low");
 56
 57/*
 58 * The Configuration/Status register
 59 *
 60 * - DS1621:
 61 *   7    6    5    4    3    2    1    0
 62 * |Done|THF |TLF |NVB | X  | X  |POL |1SHOT|
 63 *
 64 * - DS1625:
 65 *   7    6    5    4    3    2    1    0
 66 * |Done|THF |TLF |NVB | 1  | 0  |POL |1SHOT|
 67 *
 68 * - DS1631, DS1731:
 69 *   7    6    5    4    3    2    1    0
 70 * |Done|THF |TLF |NVB | R1 | R0 |POL |1SHOT|
 71 *
 72 * - DS1721:
 73 *   7    6    5    4    3    2    1    0
 74 * |Done| X  | X  | U  | R1 | R0 |POL |1SHOT|
 75 *
 76 * Where:
 77 * - 'X' is Reserved
 78 * - 'U' is Undefined
 79 */
 80#define DS1621_REG_CONFIG_NVB		0x10
 81#define DS1621_REG_CONFIG_RESOL		0x0C
 82#define DS1621_REG_CONFIG_POLARITY	0x02
 83#define DS1621_REG_CONFIG_1SHOT		0x01
 84#define DS1621_REG_CONFIG_DONE		0x80
 85
 86#define DS1621_REG_CONFIG_RESOL_SHIFT	2
 87
 88/* ds1721 conversion rates: {C/LSB, time(ms), resolution bit setting} */
 89static const unsigned short ds1721_convrates[] = {
 90	94,	/*  9-bits (0.5,  93.75, RES[0..1] = 0 */
 91	188,	/* 10-bits (0.25, 187.5, RES[0..1] = 1 */
 92	375,	/* 11-bits (0.125,  375, RES[0..1] = 2 */
 93	750,	/* 12-bits (0.0625, 750, RES[0..1] = 3 */
 94};
 95
 96#define DS1621_CONVERSION_MAX	750
 97#define DS1625_CONVERSION_MAX	500
 98
 99#define DS1621_TEMP_MAX	125000
100#define DS1621_TEMP_MIN	(-55000)
101
102/* The DS1621 temperature registers */
103static const u8 DS1621_REG_TEMP[3] = {
104	0xAA,		/* input, word, RO */
105	0xA2,		/* min, word, RW */
106	0xA1,		/* max, word, RW */
107};
108#define DS1621_REG_CONF			0xAC /* byte, RW */
109#define DS1621_COM_START		0xEE /* no data */
110#define DS1721_COM_START		0x51 /* no data */
111#define DS1621_COM_STOP			0x22 /* no data */
112
113/* The DS1621 configuration register */
114#define DS1621_ALARM_TEMP_HIGH		0x40
115#define DS1621_ALARM_TEMP_LOW		0x20
116
117/* Conversions */
118#define ALARMS_FROM_REG(val) ((val) & \
119			(DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))
120
121/* Each client has this additional data */
122struct ds1621_data {
123	struct i2c_client *client;
124	struct mutex update_lock;
125	char valid;			/* !=0 if following fields are valid */
126	unsigned long last_updated;	/* In jiffies */
127	enum chips kind;		/* device type */
128
129	u16 temp[3];			/* Register values, word */
130	u8 conf;			/* Register encoding, combined */
131	u8 zbits;			/* Resolution encoded as number of
132					 * zero bits */
133	u16 update_interval;		/* Conversion rate in milliseconds */
134};
135
136static inline int DS1621_TEMP_FROM_REG(u16 reg)
137{
138	return DIV_ROUND_CLOSEST(((s16)reg / 16) * 625, 10);
139}
140
141/*
142 * TEMP: 0.001C/bit (-55C to +125C)
143 * REG:
144 *  - 1621, 1625: 0.5C/bit, 7 zero-bits
145 *  - 1631, 1721, 1731: 0.0625C/bit, 4 zero-bits
146 */
147static inline u16 DS1621_TEMP_TO_REG(long temp, u8 zbits)
148{
149	temp = clamp_val(temp, DS1621_TEMP_MIN, DS1621_TEMP_MAX);
150	temp = DIV_ROUND_CLOSEST(temp * (1 << (8 - zbits)), 1000) << zbits;
151	return temp;
152}
153
154static void ds1621_init_client(struct ds1621_data *data,
155			       struct i2c_client *client)
156{
157	u8 conf, new_conf, sreg, resol;
158
159	new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
160	/* switch to continuous conversion mode */
161	new_conf &= ~DS1621_REG_CONFIG_1SHOT;
162
163	/* setup output polarity */
164	if (polarity == 0)
165		new_conf &= ~DS1621_REG_CONFIG_POLARITY;
166	else if (polarity == 1)
167		new_conf |= DS1621_REG_CONFIG_POLARITY;
168
169	if (conf != new_conf)
170		i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf);
171
172	switch (data->kind) {
173	case ds1625:
174		data->update_interval = DS1625_CONVERSION_MAX;
175		data->zbits = 7;
176		sreg = DS1621_COM_START;
177		break;
178	case ds1631:
179	case ds1721:
180	case ds1731:
181		resol = (new_conf & DS1621_REG_CONFIG_RESOL) >>
182			 DS1621_REG_CONFIG_RESOL_SHIFT;
183		data->update_interval = ds1721_convrates[resol];
184		data->zbits = 7 - resol;
185		sreg = DS1721_COM_START;
186		break;
187	default:
188		data->update_interval = DS1621_CONVERSION_MAX;
189		data->zbits = 7;
190		sreg = DS1621_COM_START;
191		break;
192	}
193
194	/* start conversion */
195	i2c_smbus_write_byte(client, sreg);
196}
197
198static struct ds1621_data *ds1621_update_client(struct device *dev)
199{
200	struct ds1621_data *data = dev_get_drvdata(dev);
201	struct i2c_client *client = data->client;
202	u8 new_conf;
203
204	mutex_lock(&data->update_lock);
205
206	if (time_after(jiffies, data->last_updated + data->update_interval) ||
207	    !data->valid) {
208		int i;
209
210		dev_dbg(&client->dev, "Starting ds1621 update\n");
211
212		data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
213
214		for (i = 0; i < ARRAY_SIZE(data->temp); i++)
215			data->temp[i] = i2c_smbus_read_word_swapped(client,
216							 DS1621_REG_TEMP[i]);
217
218		/* reset alarms if necessary */
219		new_conf = data->conf;
220		if (data->temp[0] > data->temp[1])	/* input > min */
221			new_conf &= ~DS1621_ALARM_TEMP_LOW;
222		if (data->temp[0] < data->temp[2])	/* input < max */
223			new_conf &= ~DS1621_ALARM_TEMP_HIGH;
224		if (data->conf != new_conf)
225			i2c_smbus_write_byte_data(client, DS1621_REG_CONF,
226						  new_conf);
227
228		data->last_updated = jiffies;
229		data->valid = 1;
230	}
231
232	mutex_unlock(&data->update_lock);
233
234	return data;
235}
236
237static ssize_t show_temp(struct device *dev, struct device_attribute *da,
238			 char *buf)
239{
240	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
241	struct ds1621_data *data = ds1621_update_client(dev);
242	return sprintf(buf, "%d\n",
243		       DS1621_TEMP_FROM_REG(data->temp[attr->index]));
244}
245
246static ssize_t set_temp(struct device *dev, struct device_attribute *da,
247			const char *buf, size_t count)
248{
249	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
250	struct ds1621_data *data = dev_get_drvdata(dev);
251	long val;
252	int err;
253
254	err = kstrtol(buf, 10, &val);
255	if (err)
256		return err;
257
258	mutex_lock(&data->update_lock);
259	data->temp[attr->index] = DS1621_TEMP_TO_REG(val, data->zbits);
260	i2c_smbus_write_word_swapped(data->client, DS1621_REG_TEMP[attr->index],
261				     data->temp[attr->index]);
262	mutex_unlock(&data->update_lock);
263	return count;
264}
265
266static ssize_t show_alarms(struct device *dev, struct device_attribute *da,
267			   char *buf)
268{
269	struct ds1621_data *data = ds1621_update_client(dev);
270	return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf));
271}
272
273static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
274			  char *buf)
275{
276	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
277	struct ds1621_data *data = ds1621_update_client(dev);
278	return sprintf(buf, "%d\n", !!(data->conf & attr->index));
279}
280
281static ssize_t show_convrate(struct device *dev, struct device_attribute *da,
282			  char *buf)
283{
284	struct ds1621_data *data = dev_get_drvdata(dev);
285	return scnprintf(buf, PAGE_SIZE, "%hu\n", data->update_interval);
286}
287
288static ssize_t set_convrate(struct device *dev, struct device_attribute *da,
289			    const char *buf, size_t count)
290{
291	struct ds1621_data *data = dev_get_drvdata(dev);
292	struct i2c_client *client = data->client;
293	unsigned long convrate;
294	s32 err;
295	int resol = 0;
296
297	err = kstrtoul(buf, 10, &convrate);
298	if (err)
299		return err;
300
301	/* Convert rate into resolution bits */
302	while (resol < (ARRAY_SIZE(ds1721_convrates) - 1) &&
303	       convrate > ds1721_convrates[resol])
304		resol++;
305
306	mutex_lock(&data->update_lock);
307	data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
308	data->conf &= ~DS1621_REG_CONFIG_RESOL;
309	data->conf |= (resol << DS1621_REG_CONFIG_RESOL_SHIFT);
310	i2c_smbus_write_byte_data(client, DS1621_REG_CONF, data->conf);
311	data->update_interval = ds1721_convrates[resol];
312	data->zbits = 7 - resol;
313	mutex_unlock(&data->update_lock);
314
315	return count;
316}
317
318static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
319static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_convrate,
320		   set_convrate);
321
322static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
323static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1);
324static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2);
325static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
326		DS1621_ALARM_TEMP_LOW);
327static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
328		DS1621_ALARM_TEMP_HIGH);
329
330static struct attribute *ds1621_attributes[] = {
331	&sensor_dev_attr_temp1_input.dev_attr.attr,
332	&sensor_dev_attr_temp1_min.dev_attr.attr,
333	&sensor_dev_attr_temp1_max.dev_attr.attr,
334	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
335	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
336	&dev_attr_alarms.attr,
337	&dev_attr_update_interval.attr,
338	NULL
339};
340
341static umode_t ds1621_attribute_visible(struct kobject *kobj,
342					struct attribute *attr, int index)
343{
344	struct device *dev = container_of(kobj, struct device, kobj);
345	struct ds1621_data *data = dev_get_drvdata(dev);
346
347	if (attr == &dev_attr_update_interval.attr)
348		if (data->kind == ds1621 || data->kind == ds1625)
349			/* shhh, we're hiding update_interval */
350			return 0;
351	return attr->mode;
352}
353
354static const struct attribute_group ds1621_group = {
355	.attrs = ds1621_attributes,
356	.is_visible = ds1621_attribute_visible
357};
358__ATTRIBUTE_GROUPS(ds1621);
359
360static int ds1621_probe(struct i2c_client *client,
361			const struct i2c_device_id *id)
362{
363	struct ds1621_data *data;
364	struct device *hwmon_dev;
365
366	data = devm_kzalloc(&client->dev, sizeof(struct ds1621_data),
367			    GFP_KERNEL);
368	if (!data)
369		return -ENOMEM;
370
371	mutex_init(&data->update_lock);
372
373	data->kind = id->driver_data;
374	data->client = client;
375
376	/* Initialize the DS1621 chip */
377	ds1621_init_client(data, client);
378
379	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
380							   client->name, data,
381							   ds1621_groups);
382	return PTR_ERR_OR_ZERO(hwmon_dev);
383}
384
385static const struct i2c_device_id ds1621_id[] = {
386	{ "ds1621", ds1621 },
387	{ "ds1625", ds1625 },
388	{ "ds1631", ds1631 },
389	{ "ds1721", ds1721 },
390	{ "ds1731", ds1731 },
391	{ }
392};
393MODULE_DEVICE_TABLE(i2c, ds1621_id);
394
395/* This is the driver that will be inserted */
396static struct i2c_driver ds1621_driver = {
397	.class		= I2C_CLASS_HWMON,
398	.driver = {
399		.name	= "ds1621",
400	},
401	.probe		= ds1621_probe,
402	.id_table	= ds1621_id,
403};
404
405module_i2c_driver(ds1621_driver);
406
407MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>");
408MODULE_DESCRIPTION("DS1621 driver");
409MODULE_LICENSE("GPL");