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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Shubhrajyoti Dcaaa0f32010-10-28 20:31:44 +02002 * lm75.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring
4 * Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/slab.h>
24#include <linux/jiffies.h>
25#include <linux/i2c.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040026#include <linux/hwmon.h>
Jean Delvare9ca8e40c82007-05-08 17:22:01 +020027#include <linux/hwmon-sysfs.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040028#include <linux/err.h>
Ingo Molnar9a61bf62006-01-18 23:19:26 +010029#include <linux/mutex.h>
Eduardo Valentin22e73182013-07-16 14:54:55 -040030#include <linux/of.h>
31#include <linux/thermal.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include "lm75.h"
33
34
David Brownell01a52392008-04-21 12:10:53 -070035/*
36 * This driver handles the LM75 and compatible digital temperature sensors.
David Brownell01a52392008-04-21 12:10:53 -070037 */
38
David Brownell9ebd3d82008-05-03 19:33:15 -070039enum lm75_type { /* keep sorted in alphabetical order */
Michael Henneriche96f9d82011-10-13 04:43:31 -040040 adt75,
Jean Delvare1f86df42009-12-14 21:17:26 +010041 ds1775,
David Brownell9ebd3d82008-05-03 19:33:15 -070042 ds75,
Jean Delvare3fbc81e2013-05-04 14:49:36 +020043 ds7505,
Arnaud Ebalardc98d6c62013-11-09 18:39:14 +010044 g751,
Jean Delvare1f86df42009-12-14 21:17:26 +010045 lm75,
David Brownell9ebd3d82008-05-03 19:33:15 -070046 lm75a,
Michael Thalmeier799fc602014-11-18 17:08:04 +010047 lm75b,
David Brownell9ebd3d82008-05-03 19:33:15 -070048 max6625,
49 max6626,
50 mcp980x,
51 stds75,
52 tcn75,
53 tmp100,
54 tmp101,
Shubhrajyoti Datta6d034052010-05-27 19:59:03 +020055 tmp105,
Frans Klaverc83959f2014-06-26 11:21:11 +020056 tmp112,
David Brownell9ebd3d82008-05-03 19:33:15 -070057 tmp175,
58 tmp275,
59 tmp75,
60};
61
Jean Delvare8ff69ee2008-08-10 22:56:16 +020062/* Addresses scanned */
Mark M. Hoffman25e9c862008-02-17 22:28:03 -050063static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
67/* The LM75 registers */
Linus Torvalds1da177e2005-04-16 15:20:36 -070068#define LM75_REG_CONF 0x01
Jean Delvare9ca8e40c82007-05-08 17:22:01 +020069static const u8 LM75_REG_TEMP[3] = {
70 0x00, /* input */
71 0x03, /* max */
72 0x02, /* hyst */
73};
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
75/* Each client has this additional data */
76struct lm75_data {
Guenter Roeckd663ec42014-01-13 16:00:37 -080077 struct i2c_client *client;
David Brownell01a52392008-04-21 12:10:53 -070078 struct device *hwmon_dev;
Eduardo Valentin22e73182013-07-16 14:54:55 -040079 struct thermal_zone_device *tz;
Ingo Molnar9a61bf62006-01-18 23:19:26 +010080 struct mutex update_lock;
David Brownell9ebd3d82008-05-03 19:33:15 -070081 u8 orig_conf;
Jean Delvare87d06212013-05-04 14:49:36 +020082 u8 resolution; /* In bits, between 9 and 12 */
83 u8 resolution_limits;
David Brownell01a52392008-04-21 12:10:53 -070084 char valid; /* !=0 if registers are valid */
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 unsigned long last_updated; /* In jiffies */
Jean Delvare87d06212013-05-04 14:49:36 +020086 unsigned long sample_time; /* In jiffies */
87 s16 temp[3]; /* Register values,
Jean Delvare9ca8e40c82007-05-08 17:22:01 +020088 0 = input
89 1 = max
90 2 = hyst */
Linus Torvalds1da177e2005-04-16 15:20:36 -070091};
92
Linus Torvalds1da177e2005-04-16 15:20:36 -070093static int lm75_read_value(struct i2c_client *client, u8 reg);
94static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
95static struct lm75_data *lm75_update_device(struct device *dev);
96
97
David Brownell01a52392008-04-21 12:10:53 -070098/*-----------------------------------------------------------------------*/
99
Eduardo Valentin22e73182013-07-16 14:54:55 -0400100static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
101{
102 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
103}
104
David Brownell01a52392008-04-21 12:10:53 -0700105/* sysfs attributes for hwmon */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
Eduardo Valentin22e73182013-07-16 14:54:55 -0400107static int lm75_read_temp(void *dev, long *temp)
108{
109 struct lm75_data *data = lm75_update_device(dev);
110
111 if (IS_ERR(data))
112 return PTR_ERR(data);
113
114 *temp = lm75_reg_to_mc(data->temp[0], data->resolution);
115
116 return 0;
117}
118
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200119static ssize_t show_temp(struct device *dev, struct device_attribute *da,
120 char *buf)
121{
122 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
123 struct lm75_data *data = lm75_update_device(dev);
Frans Meulenbroeks1f962f32012-01-03 12:02:40 +0100124
125 if (IS_ERR(data))
126 return PTR_ERR(data);
127
Eduardo Valentin22e73182013-07-16 14:54:55 -0400128 return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index],
129 data->resolution));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200132static ssize_t set_temp(struct device *dev, struct device_attribute *da,
133 const char *buf, size_t count)
134{
135 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
Guenter Roeckd663ec42014-01-13 16:00:37 -0800136 struct lm75_data *data = dev_get_drvdata(dev);
137 struct i2c_client *client = data->client;
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200138 int nr = attr->index;
Shubhrajyoti De3cd9522010-10-28 20:31:44 +0200139 long temp;
140 int error;
Jean Delvare87d06212013-05-04 14:49:36 +0200141 u8 resolution;
Shubhrajyoti De3cd9522010-10-28 20:31:44 +0200142
Frans Meulenbroeks24edc0a2012-01-03 12:02:41 +0100143 error = kstrtol(buf, 10, &temp);
Shubhrajyoti De3cd9522010-10-28 20:31:44 +0200144 if (error)
145 return error;
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200146
Jean Delvare87d06212013-05-04 14:49:36 +0200147 /*
148 * Resolution of limit registers is assumed to be the same as the
149 * temperature input register resolution unless given explicitly.
150 */
151 if (attr->index && data->resolution_limits)
152 resolution = data->resolution_limits;
153 else
154 resolution = data->resolution;
155
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200156 mutex_lock(&data->update_lock);
Jean Delvare87d06212013-05-04 14:49:36 +0200157 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
158 data->temp[nr] = DIV_ROUND_CLOSEST(temp << (resolution - 8),
159 1000) << (16 - resolution);
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200160 lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
161 mutex_unlock(&data->update_lock);
162 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200165static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
166 show_temp, set_temp, 1);
167static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
168 show_temp, set_temp, 2);
169static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
Guenter Roeckd663ec42014-01-13 16:00:37 -0800171static struct attribute *lm75_attrs[] = {
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200172 &sensor_dev_attr_temp1_input.dev_attr.attr,
173 &sensor_dev_attr_temp1_max.dev_attr.attr,
174 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
Mark M. Hoffmanc1685f62006-09-24 20:59:49 +0200175
176 NULL
177};
Guenter Roeckd663ec42014-01-13 16:00:37 -0800178ATTRIBUTE_GROUPS(lm75);
Mark M. Hoffmanc1685f62006-09-24 20:59:49 +0200179
Eduardo Valentin2251aef2014-11-07 21:24:39 -0400180static const struct thermal_zone_of_device_ops lm75_of_thermal_ops = {
181 .get_temp = lm75_read_temp,
182};
183
David Brownell01a52392008-04-21 12:10:53 -0700184/*-----------------------------------------------------------------------*/
185
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200186/* device probe and removal */
David Brownell9ebd3d82008-05-03 19:33:15 -0700187
188static int
189lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
190{
Guenter Roeckd663ec42014-01-13 16:00:37 -0800191 struct device *dev = &client->dev;
David Brownell9ebd3d82008-05-03 19:33:15 -0700192 struct lm75_data *data;
193 int status;
194 u8 set_mask, clr_mask;
195 int new;
Jean Delvare0cd2c722013-05-04 14:49:36 +0200196 enum lm75_type kind = id->driver_data;
David Brownell9ebd3d82008-05-03 19:33:15 -0700197
198 if (!i2c_check_functionality(client->adapter,
199 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
200 return -EIO;
201
Guenter Roeckd663ec42014-01-13 16:00:37 -0800202 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
David Brownell9ebd3d82008-05-03 19:33:15 -0700203 if (!data)
204 return -ENOMEM;
205
Guenter Roeckd663ec42014-01-13 16:00:37 -0800206 data->client = client;
David Brownell9ebd3d82008-05-03 19:33:15 -0700207 i2c_set_clientdata(client, data);
David Brownell9ebd3d82008-05-03 19:33:15 -0700208 mutex_init(&data->update_lock);
209
210 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
211 * Then tweak to be more precise when appropriate.
212 */
213 set_mask = 0;
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200214 clr_mask = LM75_SHUTDOWN; /* continuous conversions */
215
Jean Delvare0cd2c722013-05-04 14:49:36 +0200216 switch (kind) {
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200217 case adt75:
218 clr_mask |= 1 << 5; /* not one-shot mode */
Jean Delvare0cd2c722013-05-04 14:49:36 +0200219 data->resolution = 12;
220 data->sample_time = HZ / 8;
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200221 break;
222 case ds1775:
223 case ds75:
224 case stds75:
Jean Delvare0cd2c722013-05-04 14:49:36 +0200225 clr_mask |= 3 << 5;
226 set_mask |= 2 << 5; /* 11-bit mode */
227 data->resolution = 11;
228 data->sample_time = HZ;
229 break;
Jean Delvare3fbc81e2013-05-04 14:49:36 +0200230 case ds7505:
231 set_mask |= 3 << 5; /* 12-bit mode */
232 data->resolution = 12;
233 data->sample_time = HZ / 4;
234 break;
Arnaud Ebalardc98d6c62013-11-09 18:39:14 +0100235 case g751:
Jean Delvare0cd2c722013-05-04 14:49:36 +0200236 case lm75:
237 case lm75a:
238 data->resolution = 9;
239 data->sample_time = HZ / 2;
240 break;
Michael Thalmeier799fc602014-11-18 17:08:04 +0100241 case lm75b:
242 data->resolution = 11;
243 data->sample_time = HZ / 4;
244 break;
Jean Delvare0cd2c722013-05-04 14:49:36 +0200245 case max6625:
246 data->resolution = 9;
247 data->sample_time = HZ / 4;
248 break;
249 case max6626:
250 data->resolution = 12;
251 data->resolution_limits = 9;
252 data->sample_time = HZ / 4;
253 break;
254 case tcn75:
255 data->resolution = 9;
256 data->sample_time = HZ / 8;
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200257 break;
258 case mcp980x:
Jean Delvare0cd2c722013-05-04 14:49:36 +0200259 data->resolution_limits = 9;
260 /* fall through */
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200261 case tmp100:
262 case tmp101:
Jean Delvare0cd2c722013-05-04 14:49:36 +0200263 set_mask |= 3 << 5; /* 12-bit mode */
264 data->resolution = 12;
265 data->sample_time = HZ;
266 clr_mask |= 1 << 7; /* not one-shot mode */
267 break;
Frans Klaverc83959f2014-06-26 11:21:11 +0200268 case tmp112:
269 set_mask |= 3 << 5; /* 12-bit mode */
270 clr_mask |= 1 << 7; /* not one-shot mode */
271 data->resolution = 12;
272 data->sample_time = HZ / 4;
273 break;
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200274 case tmp105:
275 case tmp175:
276 case tmp275:
277 case tmp75:
Jean Delvare0cd2c722013-05-04 14:49:36 +0200278 set_mask |= 3 << 5; /* 12-bit mode */
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200279 clr_mask |= 1 << 7; /* not one-shot mode */
Jean Delvare0cd2c722013-05-04 14:49:36 +0200280 data->resolution = 12;
281 data->sample_time = HZ / 2;
Jean Delvare8a5c5cc2013-05-04 14:49:36 +0200282 break;
283 }
David Brownell9ebd3d82008-05-03 19:33:15 -0700284
285 /* configure as specified */
286 status = lm75_read_value(client, LM75_REG_CONF);
287 if (status < 0) {
Guenter Roeckd663ec42014-01-13 16:00:37 -0800288 dev_dbg(dev, "Can't read config? %d\n", status);
Guenter Roeck13ac7a02012-06-02 09:58:08 -0700289 return status;
David Brownell9ebd3d82008-05-03 19:33:15 -0700290 }
291 data->orig_conf = status;
292 new = status & ~clr_mask;
293 new |= set_mask;
294 if (status != new)
295 lm75_write_value(client, LM75_REG_CONF, new);
Guenter Roeckd663ec42014-01-13 16:00:37 -0800296 dev_dbg(dev, "Config %02x\n", new);
David Brownell9ebd3d82008-05-03 19:33:15 -0700297
Guenter Roeckd663ec42014-01-13 16:00:37 -0800298 data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
299 data, lm75_groups);
300 if (IS_ERR(data->hwmon_dev))
301 return PTR_ERR(data->hwmon_dev);
David Brownell9ebd3d82008-05-03 19:33:15 -0700302
Eduardo Valentin2251aef2014-11-07 21:24:39 -0400303 data->tz = thermal_zone_of_sensor_register(data->hwmon_dev, 0,
Guenter Roeckd663ec42014-01-13 16:00:37 -0800304 data->hwmon_dev,
Eduardo Valentin2251aef2014-11-07 21:24:39 -0400305 &lm75_of_thermal_ops);
Eduardo Valentin22e73182013-07-16 14:54:55 -0400306 if (IS_ERR(data->tz))
307 data->tz = NULL;
308
Guenter Roeckd663ec42014-01-13 16:00:37 -0800309 dev_info(dev, "%s: sensor '%s'\n",
Kay Sievers739cf3a2009-01-06 10:44:41 -0800310 dev_name(data->hwmon_dev), client->name);
David Brownell9ebd3d82008-05-03 19:33:15 -0700311
312 return 0;
David Brownell9ebd3d82008-05-03 19:33:15 -0700313}
314
315static int lm75_remove(struct i2c_client *client)
316{
317 struct lm75_data *data = i2c_get_clientdata(client);
318
Guenter Roeckd663ec42014-01-13 16:00:37 -0800319 thermal_zone_of_sensor_unregister(data->hwmon_dev, data->tz);
David Brownell9ebd3d82008-05-03 19:33:15 -0700320 hwmon_device_unregister(data->hwmon_dev);
David Brownell9ebd3d82008-05-03 19:33:15 -0700321 lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
David Brownell9ebd3d82008-05-03 19:33:15 -0700322 return 0;
323}
324
325static const struct i2c_device_id lm75_ids[] = {
Michael Henneriche96f9d82011-10-13 04:43:31 -0400326 { "adt75", adt75, },
David Brownell9ebd3d82008-05-03 19:33:15 -0700327 { "ds1775", ds1775, },
328 { "ds75", ds75, },
Jean Delvare3fbc81e2013-05-04 14:49:36 +0200329 { "ds7505", ds7505, },
Arnaud Ebalardc98d6c62013-11-09 18:39:14 +0100330 { "g751", g751, },
David Brownell9ebd3d82008-05-03 19:33:15 -0700331 { "lm75", lm75, },
332 { "lm75a", lm75a, },
Michael Thalmeier799fc602014-11-18 17:08:04 +0100333 { "lm75b", lm75b, },
David Brownell9ebd3d82008-05-03 19:33:15 -0700334 { "max6625", max6625, },
335 { "max6626", max6626, },
336 { "mcp980x", mcp980x, },
337 { "stds75", stds75, },
338 { "tcn75", tcn75, },
339 { "tmp100", tmp100, },
340 { "tmp101", tmp101, },
Shubhrajyoti Datta6d034052010-05-27 19:59:03 +0200341 { "tmp105", tmp105, },
Frans Klaverc83959f2014-06-26 11:21:11 +0200342 { "tmp112", tmp112, },
David Brownell9ebd3d82008-05-03 19:33:15 -0700343 { "tmp175", tmp175, },
344 { "tmp275", tmp275, },
345 { "tmp75", tmp75, },
346 { /* LIST END */ }
347};
348MODULE_DEVICE_TABLE(i2c, lm75_ids);
349
Len Sorensen05e82fe2011-03-21 17:59:36 +0100350#define LM75A_ID 0xA1
351
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200352/* Return 0 if detection is successful, -ENODEV otherwise */
Jean Delvare310ec792009-12-14 21:17:23 +0100353static int lm75_detect(struct i2c_client *new_client,
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200354 struct i2c_board_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200356 struct i2c_adapter *adapter = new_client->adapter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 int i;
Jean Delvaree76f67b2011-03-21 17:59:36 +0100358 int conf, hyst, os;
Len Sorensen05e82fe2011-03-21 17:59:36 +0100359 bool is_lm75a = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
362 I2C_FUNC_SMBUS_WORD_DATA))
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200363 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364
Jean Delvare426343e2011-10-13 17:15:11 -0400365 /*
366 * Now, we do the remaining detection. There is no identification-
367 * dedicated register so we have to rely on several tricks:
368 * unused bits, registers cycling over 8-address boundaries,
369 * addresses 0x04-0x07 returning the last read value.
370 * The cycling+unused addresses combination is not tested,
371 * since it would significantly slow the detection down and would
372 * hardly add any value.
373 *
374 * The National Semiconductor LM75A is different than earlier
375 * LM75s. It has an ID byte of 0xaX (where X is the chip
376 * revision, with 1 being the only revision in existence) in
377 * register 7, and unused registers return 0xff rather than the
378 * last read value.
379 *
380 * Note that this function only detects the original National
381 * Semiconductor LM75 and the LM75A. Clones from other vendors
382 * aren't detected, on purpose, because they are typically never
383 * found on PC hardware. They are found on embedded designs where
384 * they can be instantiated explicitly so detection is not needed.
385 * The absence of identification registers on all these clones
386 * would make their exhaustive detection very difficult and weak,
387 * and odds are that the driver would bind to unsupported devices.
388 */
Len Sorensen05e82fe2011-03-21 17:59:36 +0100389
Jean Delvaree76f67b2011-03-21 17:59:36 +0100390 /* Unused bits */
Jean Delvare52df6442009-12-09 20:35:57 +0100391 conf = i2c_smbus_read_byte_data(new_client, 1);
Jean Delvaree76f67b2011-03-21 17:59:36 +0100392 if (conf & 0xe0)
393 return -ENODEV;
Len Sorensen05e82fe2011-03-21 17:59:36 +0100394
395 /* First check for LM75A */
396 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
397 /* LM75A returns 0xff on unused registers so
398 just to be sure we check for that too. */
399 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
400 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
401 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
402 return -ENODEV;
403 is_lm75a = 1;
Jean Delvaree76f67b2011-03-21 17:59:36 +0100404 hyst = i2c_smbus_read_byte_data(new_client, 2);
405 os = i2c_smbus_read_byte_data(new_client, 3);
Len Sorensen05e82fe2011-03-21 17:59:36 +0100406 } else { /* Traditional style LM75 detection */
407 /* Unused addresses */
Jean Delvaree76f67b2011-03-21 17:59:36 +0100408 hyst = i2c_smbus_read_byte_data(new_client, 2);
409 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
410 || i2c_smbus_read_byte_data(new_client, 5) != hyst
411 || i2c_smbus_read_byte_data(new_client, 6) != hyst
412 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
Len Sorensen05e82fe2011-03-21 17:59:36 +0100413 return -ENODEV;
Jean Delvaree76f67b2011-03-21 17:59:36 +0100414 os = i2c_smbus_read_byte_data(new_client, 3);
415 if (i2c_smbus_read_byte_data(new_client, 4) != os
416 || i2c_smbus_read_byte_data(new_client, 5) != os
417 || i2c_smbus_read_byte_data(new_client, 6) != os
418 || i2c_smbus_read_byte_data(new_client, 7) != os)
Len Sorensen05e82fe2011-03-21 17:59:36 +0100419 return -ENODEV;
420 }
Guenter Roeck4ad40cc2014-12-04 09:58:15 -0800421 /*
422 * It is very unlikely that this is a LM75 if both
423 * hysteresis and temperature limit registers are 0.
424 */
425 if (hyst == 0 && os == 0)
426 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
Jean Delvare52df6442009-12-09 20:35:57 +0100428 /* Addresses cycling */
Jean Delvaree76f67b2011-03-21 17:59:36 +0100429 for (i = 8; i <= 248; i += 40) {
Jean Delvare52df6442009-12-09 20:35:57 +0100430 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
Jean Delvaree76f67b2011-03-21 17:59:36 +0100431 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
432 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
Jean Delvare52df6442009-12-09 20:35:57 +0100433 return -ENODEV;
Len Sorensen05e82fe2011-03-21 17:59:36 +0100434 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
435 != LM75A_ID)
436 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 }
438
Len Sorensen05e82fe2011-03-21 17:59:36 +0100439 strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
Mark M. Hoffmanc1685f62006-09-24 20:59:49 +0200440
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442}
443
Shubhrajyoti Datta99145182010-08-14 21:08:50 +0200444#ifdef CONFIG_PM
445static int lm75_suspend(struct device *dev)
446{
447 int status;
448 struct i2c_client *client = to_i2c_client(dev);
449 status = lm75_read_value(client, LM75_REG_CONF);
450 if (status < 0) {
451 dev_dbg(&client->dev, "Can't read config? %d\n", status);
452 return status;
453 }
454 status = status | LM75_SHUTDOWN;
455 lm75_write_value(client, LM75_REG_CONF, status);
456 return 0;
457}
458
459static int lm75_resume(struct device *dev)
460{
461 int status;
462 struct i2c_client *client = to_i2c_client(dev);
463 status = lm75_read_value(client, LM75_REG_CONF);
464 if (status < 0) {
465 dev_dbg(&client->dev, "Can't read config? %d\n", status);
466 return status;
467 }
468 status = status & ~LM75_SHUTDOWN;
469 lm75_write_value(client, LM75_REG_CONF, status);
470 return 0;
471}
472
473static const struct dev_pm_ops lm75_dev_pm_ops = {
474 .suspend = lm75_suspend,
475 .resume = lm75_resume,
476};
477#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
478#else
479#define LM75_DEV_PM_OPS NULL
480#endif /* CONFIG_PM */
481
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200482static struct i2c_driver lm75_driver = {
483 .class = I2C_CLASS_HWMON,
David Brownell01a52392008-04-21 12:10:53 -0700484 .driver = {
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200485 .name = "lm75",
Shubhrajyoti Datta99145182010-08-14 21:08:50 +0200486 .pm = LM75_DEV_PM_OPS,
David Brownell01a52392008-04-21 12:10:53 -0700487 },
Jean Delvare8ff69ee2008-08-10 22:56:16 +0200488 .probe = lm75_probe,
489 .remove = lm75_remove,
490 .id_table = lm75_ids,
491 .detect = lm75_detect,
Jean Delvarec3813d62009-12-14 21:17:25 +0100492 .address_list = normal_i2c,
David Brownell01a52392008-04-21 12:10:53 -0700493};
494
495/*-----------------------------------------------------------------------*/
496
497/* register access */
498
Shubhrajyoti Dcaaa0f32010-10-28 20:31:44 +0200499/*
500 * All registers are word-sized, except for the configuration register.
501 * LM75 uses a high-byte first convention, which is exactly opposite to
502 * the SMBus standard.
503 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504static int lm75_read_value(struct i2c_client *client, u8 reg)
505{
506 if (reg == LM75_REG_CONF)
507 return i2c_smbus_read_byte_data(client, reg);
Jean Delvare90f41022011-11-04 12:00:47 +0100508 else
509 return i2c_smbus_read_word_swapped(client, reg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510}
511
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
513{
514 if (reg == LM75_REG_CONF)
515 return i2c_smbus_write_byte_data(client, reg, value);
516 else
Jean Delvare90f41022011-11-04 12:00:47 +0100517 return i2c_smbus_write_word_swapped(client, reg, value);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518}
519
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520static struct lm75_data *lm75_update_device(struct device *dev)
521{
Guenter Roeckd663ec42014-01-13 16:00:37 -0800522 struct lm75_data *data = dev_get_drvdata(dev);
523 struct i2c_client *client = data->client;
Frans Meulenbroeks1f962f32012-01-03 12:02:40 +0100524 struct lm75_data *ret = data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100526 mutex_lock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
Jean Delvare87d06212013-05-04 14:49:36 +0200528 if (time_after(jiffies, data->last_updated + data->sample_time)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 || !data->valid) {
Jean Delvare9ca8e40c82007-05-08 17:22:01 +0200530 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 dev_dbg(&client->dev, "Starting lm75 update\n");
532
David Brownellbcccc3a2008-05-03 19:19:16 -0700533 for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
534 int status;
535
536 status = lm75_read_value(client, LM75_REG_TEMP[i]);
Frans Meulenbroeks1f962f32012-01-03 12:02:40 +0100537 if (unlikely(status < 0)) {
538 dev_dbg(dev,
539 "LM75: Failed to read value: reg %d, error %d\n",
540 LM75_REG_TEMP[i], status);
541 ret = ERR_PTR(status);
542 data->valid = 0;
543 goto abort;
544 }
545 data->temp[i] = status;
David Brownellbcccc3a2008-05-03 19:19:16 -0700546 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 data->last_updated = jiffies;
548 data->valid = 1;
549 }
550
Frans Meulenbroeks1f962f32012-01-03 12:02:40 +0100551abort:
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100552 mutex_unlock(&data->update_lock);
Frans Meulenbroeks1f962f32012-01-03 12:02:40 +0100553 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554}
555
Axel Linf0967ee2012-01-20 15:38:18 +0800556module_i2c_driver(lm75_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
558MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
559MODULE_DESCRIPTION("LM75 driver");
560MODULE_LICENSE("GPL");