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1/* tmp421.c
2 *
3 * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
4 * Preliminary support by:
5 * Melvin Rook, Raymond Ng
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/*
19 * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
20 * Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
21 */
22
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/slab.h>
26#include <linux/jiffies.h>
27#include <linux/i2c.h>
28#include <linux/hwmon.h>
29#include <linux/hwmon-sysfs.h>
30#include <linux/err.h>
31#include <linux/mutex.h>
32#include <linux/sysfs.h>
33
34/* Addresses to scan */
35static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
36 I2C_CLIENT_END };
37
38enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
39
40/* The TMP421 registers */
41#define TMP421_STATUS_REG 0x08
42#define TMP421_CONFIG_REG_1 0x09
43#define TMP421_CONVERSION_RATE_REG 0x0B
44#define TMP421_MANUFACTURER_ID_REG 0xFE
45#define TMP421_DEVICE_ID_REG 0xFF
46
47static const u8 TMP421_TEMP_MSB[4] = { 0x00, 0x01, 0x02, 0x03 };
48static const u8 TMP421_TEMP_LSB[4] = { 0x10, 0x11, 0x12, 0x13 };
49
50/* Flags */
51#define TMP421_CONFIG_SHUTDOWN 0x40
52#define TMP421_CONFIG_RANGE 0x04
53
54/* Manufacturer / Device ID's */
55#define TMP421_MANUFACTURER_ID 0x55
56#define TMP421_DEVICE_ID 0x21
57#define TMP422_DEVICE_ID 0x22
58#define TMP423_DEVICE_ID 0x23
59#define TMP441_DEVICE_ID 0x41
60#define TMP442_DEVICE_ID 0x42
61
62static const struct i2c_device_id tmp421_id[] = {
63 { "tmp421", 2 },
64 { "tmp422", 3 },
65 { "tmp423", 4 },
66 { "tmp441", 2 },
67 { "tmp442", 3 },
68 { }
69};
70MODULE_DEVICE_TABLE(i2c, tmp421_id);
71
72struct tmp421_data {
73 struct i2c_client *client;
74 struct mutex update_lock;
75 char valid;
76 unsigned long last_updated;
77 int channels;
78 u8 config;
79 s16 temp[4];
80};
81
82static int temp_from_s16(s16 reg)
83{
84 /* Mask out status bits */
85 int temp = reg & ~0xf;
86
87 return (temp * 1000 + 128) / 256;
88}
89
90static int temp_from_u16(u16 reg)
91{
92 /* Mask out status bits */
93 int temp = reg & ~0xf;
94
95 /* Add offset for extended temperature range. */
96 temp -= 64 * 256;
97
98 return (temp * 1000 + 128) / 256;
99}
100
101static struct tmp421_data *tmp421_update_device(struct device *dev)
102{
103 struct tmp421_data *data = dev_get_drvdata(dev);
104 struct i2c_client *client = data->client;
105 int i;
106
107 mutex_lock(&data->update_lock);
108
109 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
110 data->config = i2c_smbus_read_byte_data(client,
111 TMP421_CONFIG_REG_1);
112
113 for (i = 0; i < data->channels; i++) {
114 data->temp[i] = i2c_smbus_read_byte_data(client,
115 TMP421_TEMP_MSB[i]) << 8;
116 data->temp[i] |= i2c_smbus_read_byte_data(client,
117 TMP421_TEMP_LSB[i]);
118 }
119 data->last_updated = jiffies;
120 data->valid = 1;
121 }
122
123 mutex_unlock(&data->update_lock);
124
125 return data;
126}
127
128static ssize_t show_temp_value(struct device *dev,
129 struct device_attribute *devattr, char *buf)
130{
131 int index = to_sensor_dev_attr(devattr)->index;
132 struct tmp421_data *data = tmp421_update_device(dev);
133 int temp;
134
135 mutex_lock(&data->update_lock);
136 if (data->config & TMP421_CONFIG_RANGE)
137 temp = temp_from_u16(data->temp[index]);
138 else
139 temp = temp_from_s16(data->temp[index]);
140 mutex_unlock(&data->update_lock);
141
142 return sprintf(buf, "%d\n", temp);
143}
144
145static ssize_t show_fault(struct device *dev,
146 struct device_attribute *devattr, char *buf)
147{
148 int index = to_sensor_dev_attr(devattr)->index;
149 struct tmp421_data *data = tmp421_update_device(dev);
150
151 /*
152 * The OPEN bit signals a fault. This is bit 0 of the temperature
153 * register (low byte).
154 */
155 if (data->temp[index] & 0x01)
156 return sprintf(buf, "1\n");
157 else
158 return sprintf(buf, "0\n");
159}
160
161static umode_t tmp421_is_visible(struct kobject *kobj, struct attribute *a,
162 int n)
163{
164 struct device *dev = container_of(kobj, struct device, kobj);
165 struct tmp421_data *data = dev_get_drvdata(dev);
166 struct device_attribute *devattr;
167 unsigned int index;
168
169 devattr = container_of(a, struct device_attribute, attr);
170 index = to_sensor_dev_attr(devattr)->index;
171
172 if (index < data->channels)
173 return a->mode;
174
175 return 0;
176}
177
178static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0);
179static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1);
180static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
181static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp_value, NULL, 2);
182static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
183static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp_value, NULL, 3);
184static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
185
186static struct attribute *tmp421_attr[] = {
187 &sensor_dev_attr_temp1_input.dev_attr.attr,
188 &sensor_dev_attr_temp2_input.dev_attr.attr,
189 &sensor_dev_attr_temp2_fault.dev_attr.attr,
190 &sensor_dev_attr_temp3_input.dev_attr.attr,
191 &sensor_dev_attr_temp3_fault.dev_attr.attr,
192 &sensor_dev_attr_temp4_input.dev_attr.attr,
193 &sensor_dev_attr_temp4_fault.dev_attr.attr,
194 NULL
195};
196
197static const struct attribute_group tmp421_group = {
198 .attrs = tmp421_attr,
199 .is_visible = tmp421_is_visible,
200};
201
202static const struct attribute_group *tmp421_groups[] = {
203 &tmp421_group,
204 NULL
205};
206
207static int tmp421_init_client(struct i2c_client *client)
208{
209 int config, config_orig;
210
211 /* Set the conversion rate to 2 Hz */
212 i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
213
214 /* Start conversions (disable shutdown if necessary) */
215 config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
216 if (config < 0) {
217 dev_err(&client->dev,
218 "Could not read configuration register (%d)\n", config);
219 return config;
220 }
221
222 config_orig = config;
223 config &= ~TMP421_CONFIG_SHUTDOWN;
224
225 if (config != config_orig) {
226 dev_info(&client->dev, "Enable monitoring chip\n");
227 i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
228 }
229
230 return 0;
231}
232
233static int tmp421_detect(struct i2c_client *client,
234 struct i2c_board_info *info)
235{
236 enum chips kind;
237 struct i2c_adapter *adapter = client->adapter;
238 const char * const names[] = { "TMP421", "TMP422", "TMP423",
239 "TMP441", "TMP442" };
240 int addr = client->addr;
241 u8 reg;
242
243 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
244 return -ENODEV;
245
246 reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
247 if (reg != TMP421_MANUFACTURER_ID)
248 return -ENODEV;
249
250 reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
251 if (reg & 0xf8)
252 return -ENODEV;
253
254 reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
255 if (reg & 0x7f)
256 return -ENODEV;
257
258 reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
259 switch (reg) {
260 case TMP421_DEVICE_ID:
261 kind = tmp421;
262 break;
263 case TMP422_DEVICE_ID:
264 if (addr == 0x2a)
265 return -ENODEV;
266 kind = tmp422;
267 break;
268 case TMP423_DEVICE_ID:
269 if (addr != 0x4c && addr != 0x4d)
270 return -ENODEV;
271 kind = tmp423;
272 break;
273 case TMP441_DEVICE_ID:
274 kind = tmp441;
275 break;
276 case TMP442_DEVICE_ID:
277 if (addr != 0x4c && addr != 0x4d)
278 return -ENODEV;
279 kind = tmp442;
280 break;
281 default:
282 return -ENODEV;
283 }
284
285 strlcpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
286 dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
287 names[kind], client->addr);
288
289 return 0;
290}
291
292static int tmp421_probe(struct i2c_client *client,
293 const struct i2c_device_id *id)
294{
295 struct device *dev = &client->dev;
296 struct device *hwmon_dev;
297 struct tmp421_data *data;
298 int err;
299
300 data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
301 if (!data)
302 return -ENOMEM;
303
304 mutex_init(&data->update_lock);
305 data->channels = id->driver_data;
306 data->client = client;
307
308 err = tmp421_init_client(client);
309 if (err)
310 return err;
311
312 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
313 data, tmp421_groups);
314 return PTR_ERR_OR_ZERO(hwmon_dev);
315}
316
317static struct i2c_driver tmp421_driver = {
318 .class = I2C_CLASS_HWMON,
319 .driver = {
320 .name = "tmp421",
321 },
322 .probe = tmp421_probe,
323 .id_table = tmp421_id,
324 .detect = tmp421_detect,
325 .address_list = normal_i2c,
326};
327
328module_i2c_driver(tmp421_driver);
329
330MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
331MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
332MODULE_LICENSE("GPL");
1/* tmp421.c
2 *
3 * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
4 * Preliminary support by:
5 * Melvin Rook, Raymond Ng
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/*
19 * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
20 * Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
21 */
22
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/slab.h>
26#include <linux/jiffies.h>
27#include <linux/i2c.h>
28#include <linux/hwmon.h>
29#include <linux/hwmon-sysfs.h>
30#include <linux/err.h>
31#include <linux/mutex.h>
32#include <linux/sysfs.h>
33
34/* Addresses to scan */
35static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
36 I2C_CLIENT_END };
37
38enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
39
40/* The TMP421 registers */
41#define TMP421_STATUS_REG 0x08
42#define TMP421_CONFIG_REG_1 0x09
43#define TMP421_CONVERSION_RATE_REG 0x0B
44#define TMP421_MANUFACTURER_ID_REG 0xFE
45#define TMP421_DEVICE_ID_REG 0xFF
46
47static const u8 TMP421_TEMP_MSB[4] = { 0x00, 0x01, 0x02, 0x03 };
48static const u8 TMP421_TEMP_LSB[4] = { 0x10, 0x11, 0x12, 0x13 };
49
50/* Flags */
51#define TMP421_CONFIG_SHUTDOWN 0x40
52#define TMP421_CONFIG_RANGE 0x04
53
54/* Manufacturer / Device ID's */
55#define TMP421_MANUFACTURER_ID 0x55
56#define TMP421_DEVICE_ID 0x21
57#define TMP422_DEVICE_ID 0x22
58#define TMP423_DEVICE_ID 0x23
59#define TMP441_DEVICE_ID 0x41
60#define TMP442_DEVICE_ID 0x42
61
62static const struct i2c_device_id tmp421_id[] = {
63 { "tmp421", 2 },
64 { "tmp422", 3 },
65 { "tmp423", 4 },
66 { "tmp441", 2 },
67 { "tmp442", 3 },
68 { }
69};
70MODULE_DEVICE_TABLE(i2c, tmp421_id);
71
72struct tmp421_data {
73 struct i2c_client *client;
74 struct mutex update_lock;
75 u32 temp_config[5];
76 struct hwmon_channel_info temp_info;
77 const struct hwmon_channel_info *info[2];
78 struct hwmon_chip_info chip;
79 char valid;
80 unsigned long last_updated;
81 int channels;
82 u8 config;
83 s16 temp[4];
84};
85
86static int temp_from_s16(s16 reg)
87{
88 /* Mask out status bits */
89 int temp = reg & ~0xf;
90
91 return (temp * 1000 + 128) / 256;
92}
93
94static int temp_from_u16(u16 reg)
95{
96 /* Mask out status bits */
97 int temp = reg & ~0xf;
98
99 /* Add offset for extended temperature range. */
100 temp -= 64 * 256;
101
102 return (temp * 1000 + 128) / 256;
103}
104
105static struct tmp421_data *tmp421_update_device(struct device *dev)
106{
107 struct tmp421_data *data = dev_get_drvdata(dev);
108 struct i2c_client *client = data->client;
109 int i;
110
111 mutex_lock(&data->update_lock);
112
113 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
114 data->config = i2c_smbus_read_byte_data(client,
115 TMP421_CONFIG_REG_1);
116
117 for (i = 0; i < data->channels; i++) {
118 data->temp[i] = i2c_smbus_read_byte_data(client,
119 TMP421_TEMP_MSB[i]) << 8;
120 data->temp[i] |= i2c_smbus_read_byte_data(client,
121 TMP421_TEMP_LSB[i]);
122 }
123 data->last_updated = jiffies;
124 data->valid = 1;
125 }
126
127 mutex_unlock(&data->update_lock);
128
129 return data;
130}
131
132static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
133 u32 attr, int channel, long *val)
134{
135 struct tmp421_data *tmp421 = tmp421_update_device(dev);
136
137 switch (attr) {
138 case hwmon_temp_input:
139 if (tmp421->config & TMP421_CONFIG_RANGE)
140 *val = temp_from_u16(tmp421->temp[channel]);
141 else
142 *val = temp_from_s16(tmp421->temp[channel]);
143 return 0;
144 case hwmon_temp_fault:
145 /*
146 * The OPEN bit signals a fault. This is bit 0 of the temperature
147 * register (low byte).
148 */
149 *val = tmp421->temp[channel] & 0x01;
150 return 0;
151 default:
152 return -EOPNOTSUPP;
153 }
154
155}
156
157static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
158 u32 attr, int channel)
159{
160 switch (attr) {
161 case hwmon_temp_fault:
162 if (channel == 0)
163 return 0;
164 return S_IRUGO;
165 case hwmon_temp_input:
166 return S_IRUGO;
167 default:
168 return 0;
169 }
170}
171
172static int tmp421_init_client(struct i2c_client *client)
173{
174 int config, config_orig;
175
176 /* Set the conversion rate to 2 Hz */
177 i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
178
179 /* Start conversions (disable shutdown if necessary) */
180 config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
181 if (config < 0) {
182 dev_err(&client->dev,
183 "Could not read configuration register (%d)\n", config);
184 return config;
185 }
186
187 config_orig = config;
188 config &= ~TMP421_CONFIG_SHUTDOWN;
189
190 if (config != config_orig) {
191 dev_info(&client->dev, "Enable monitoring chip\n");
192 i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
193 }
194
195 return 0;
196}
197
198static int tmp421_detect(struct i2c_client *client,
199 struct i2c_board_info *info)
200{
201 enum chips kind;
202 struct i2c_adapter *adapter = client->adapter;
203 const char * const names[] = { "TMP421", "TMP422", "TMP423",
204 "TMP441", "TMP442" };
205 int addr = client->addr;
206 u8 reg;
207
208 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
209 return -ENODEV;
210
211 reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
212 if (reg != TMP421_MANUFACTURER_ID)
213 return -ENODEV;
214
215 reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
216 if (reg & 0xf8)
217 return -ENODEV;
218
219 reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
220 if (reg & 0x7f)
221 return -ENODEV;
222
223 reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
224 switch (reg) {
225 case TMP421_DEVICE_ID:
226 kind = tmp421;
227 break;
228 case TMP422_DEVICE_ID:
229 if (addr == 0x2a)
230 return -ENODEV;
231 kind = tmp422;
232 break;
233 case TMP423_DEVICE_ID:
234 if (addr != 0x4c && addr != 0x4d)
235 return -ENODEV;
236 kind = tmp423;
237 break;
238 case TMP441_DEVICE_ID:
239 kind = tmp441;
240 break;
241 case TMP442_DEVICE_ID:
242 if (addr != 0x4c && addr != 0x4d)
243 return -ENODEV;
244 kind = tmp442;
245 break;
246 default:
247 return -ENODEV;
248 }
249
250 strlcpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
251 dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
252 names[kind], client->addr);
253
254 return 0;
255}
256
257static const struct hwmon_ops tmp421_ops = {
258 .is_visible = tmp421_is_visible,
259 .read = tmp421_read,
260};
261
262static int tmp421_probe(struct i2c_client *client,
263 const struct i2c_device_id *id)
264{
265 struct device *dev = &client->dev;
266 struct device *hwmon_dev;
267 struct tmp421_data *data;
268 int i, err;
269
270 data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
271 if (!data)
272 return -ENOMEM;
273
274 mutex_init(&data->update_lock);
275 data->channels = id->driver_data;
276 data->client = client;
277
278 err = tmp421_init_client(client);
279 if (err)
280 return err;
281
282 for (i = 0; i < data->channels; i++)
283 data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT;
284
285 data->chip.ops = &tmp421_ops;
286 data->chip.info = data->info;
287
288 data->info[0] = &data->temp_info;
289
290 data->temp_info.type = hwmon_temp;
291 data->temp_info.config = data->temp_config;
292
293 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
294 data,
295 &data->chip,
296 NULL);
297 return PTR_ERR_OR_ZERO(hwmon_dev);
298}
299
300static struct i2c_driver tmp421_driver = {
301 .class = I2C_CLASS_HWMON,
302 .driver = {
303 .name = "tmp421",
304 },
305 .probe = tmp421_probe,
306 .id_table = tmp421_id,
307 .detect = tmp421_detect,
308 .address_list = normal_i2c,
309};
310
311module_i2c_driver(tmp421_driver);
312
313MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
314MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
315MODULE_LICENSE("GPL");