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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring
4 * Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
5 *
6 * Inspired from the lm83 driver. The W83L785TS-S is a sensor chip made
7 * by Winbond. It reports a single external temperature with a 1 deg
8 * resolution and a 3 deg accuracy. Datasheet can be obtained from
9 * Winbond's website at:
10 * http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf
11 *
12 * Ported to Linux 2.6 by Wolfgang Ziegler <nuppla@gmx.at> and Jean Delvare
13 * <khali@linux-fr.org>.
14 *
15 * Thanks to James Bolt <james@evilpenguin.com> for benchmarking the read
16 * error handling mechanism.
17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation; either version 2 of the License, or
21 * (at your option) any later version.
22 *
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
31 */
32
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/module.h>
34#include <linux/delay.h>
35#include <linux/init.h>
36#include <linux/slab.h>
37#include <linux/jiffies.h>
38#include <linux/i2c.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040039#include <linux/hwmon.h>
Jean Delvare709439a2005-09-25 16:41:18 +020040#include <linux/hwmon-sysfs.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040041#include <linux/err.h>
Ingo Molnar9a61bf62006-01-18 23:19:26 +010042#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
44/* How many retries on register read error */
45#define MAX_RETRIES 5
46
47/*
48 * Address to scan
49 * Address is fully defined internally and cannot be changed.
50 */
51
52static unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54/*
55 * Insmod parameters
56 */
57
Jean Delvaref4b50262005-07-31 21:49:03 +020058I2C_CLIENT_INSMOD_1(w83l785ts);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60/*
61 * The W83L785TS-S registers
62 * Manufacturer ID is 0x5CA3 for Winbond.
63 */
64
65#define W83L785TS_REG_MAN_ID1 0x4D
66#define W83L785TS_REG_MAN_ID2 0x4C
67#define W83L785TS_REG_CHIP_ID 0x4E
68#define W83L785TS_REG_CONFIG 0x40
69#define W83L785TS_REG_TYPE 0x52
70#define W83L785TS_REG_TEMP 0x27
71#define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */
72
73/*
74 * Conversions
75 * The W83L785TS-S uses signed 8-bit values.
76 */
77
Jean Delvarecb929ea2005-09-25 16:45:03 +020078#define TEMP_FROM_REG(val) ((val) * 1000)
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
80/*
81 * Functions declaration
82 */
83
84static int w83l785ts_attach_adapter(struct i2c_adapter *adapter);
85static int w83l785ts_detect(struct i2c_adapter *adapter, int address,
86 int kind);
87static int w83l785ts_detach_client(struct i2c_client *client);
88static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
89static struct w83l785ts_data *w83l785ts_update_device(struct device *dev);
90
91/*
92 * Driver data (common to all clients)
93 */
94
95static struct i2c_driver w83l785ts_driver = {
Laurent Riffardcdaf7932005-11-26 20:37:41 +010096 .driver = {
Laurent Riffardcdaf7932005-11-26 20:37:41 +010097 .name = "w83l785ts",
98 },
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 .id = I2C_DRIVERID_W83L785TS,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 .attach_adapter = w83l785ts_attach_adapter,
101 .detach_client = w83l785ts_detach_client,
102};
103
104/*
105 * Client data (each client gets its own)
106 */
107
108struct w83l785ts_data {
109 struct i2c_client client;
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400110 struct class_device *class_dev;
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100111 struct mutex update_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 char valid; /* zero until following fields are valid */
113 unsigned long last_updated; /* in jiffies */
114
115 /* registers values */
Jean Delvarecb929ea2005-09-25 16:45:03 +0200116 s8 temp[2]; /* 0: input
Jean Delvare709439a2005-09-25 16:41:18 +0200117 1: critical limit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118};
119
120/*
121 * Sysfs stuff
122 */
123
Jean Delvare709439a2005-09-25 16:41:18 +0200124static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
125 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126{
Jean Delvare709439a2005-09-25 16:41:18 +0200127 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 struct w83l785ts_data *data = w83l785ts_update_device(dev);
Jean Delvare709439a2005-09-25 16:41:18 +0200129 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130}
131
Jean Delvare709439a2005-09-25 16:41:18 +0200132static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
133static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
135/*
136 * Real code
137 */
138
139static int w83l785ts_attach_adapter(struct i2c_adapter *adapter)
140{
141 if (!(adapter->class & I2C_CLASS_HWMON))
142 return 0;
Jean Delvare2ed2dc32005-07-31 21:42:02 +0200143 return i2c_probe(adapter, &addr_data, w83l785ts_detect);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144}
145
146/*
147 * The following function does more than just detection. If detection
148 * succeeds, it also registers the new chip.
149 */
150static int w83l785ts_detect(struct i2c_adapter *adapter, int address, int kind)
151{
152 struct i2c_client *new_client;
153 struct w83l785ts_data *data;
154 int err = 0;
155
156
157 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
158 goto exit;
159
Deepak Saxenaba9c2e82005-10-17 23:08:32 +0200160 if (!(data = kzalloc(sizeof(struct w83l785ts_data), GFP_KERNEL))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 err = -ENOMEM;
162 goto exit;
163 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
165 /* The common I2C client data is placed right before the
166 * W83L785TS-specific data. */
167 new_client = &data->client;
168 i2c_set_clientdata(new_client, data);
169 new_client->addr = address;
170 new_client->adapter = adapter;
171 new_client->driver = &w83l785ts_driver;
172 new_client->flags = 0;
173
174 /*
175 * Now we do the remaining detection. A negative kind means that
176 * the driver was loaded with no force parameter (default), so we
177 * must both detect and identify the chip (actually there is only
178 * one possible kind of chip for now, W83L785TS-S). A zero kind means
179 * that the driver was loaded with the force parameter, the detection
180 * step shall be skipped. A positive kind means that the driver
181 * was loaded with the force parameter and a given kind of chip is
182 * requested, so both the detection and the identification steps
183 * are skipped.
184 */
185 if (kind < 0) { /* detection */
186 if (((w83l785ts_read_value(new_client,
187 W83L785TS_REG_CONFIG, 0) & 0x80) != 0x00)
188 || ((w83l785ts_read_value(new_client,
189 W83L785TS_REG_TYPE, 0) & 0xFC) != 0x00)) {
190 dev_dbg(&adapter->dev,
191 "W83L785TS-S detection failed at 0x%02x.\n",
192 address);
193 goto exit_free;
194 }
195 }
196
197 if (kind <= 0) { /* identification */
198 u16 man_id;
199 u8 chip_id;
200
201 man_id = (w83l785ts_read_value(new_client,
202 W83L785TS_REG_MAN_ID1, 0) << 8) +
203 w83l785ts_read_value(new_client,
204 W83L785TS_REG_MAN_ID2, 0);
205 chip_id = w83l785ts_read_value(new_client,
206 W83L785TS_REG_CHIP_ID, 0);
207
208 if (man_id == 0x5CA3) { /* Winbond */
209 if (chip_id == 0x70) { /* W83L785TS-S */
210 kind = w83l785ts;
211 }
212 }
213
214 if (kind <= 0) { /* identification failed */
215 dev_info(&adapter->dev,
216 "Unsupported chip (man_id=0x%04X, "
217 "chip_id=0x%02X).\n", man_id, chip_id);
218 goto exit_free;
219 }
220 }
221
222 /* We can fill in the remaining client fields. */
223 strlcpy(new_client->name, "w83l785ts", I2C_NAME_SIZE);
224 data->valid = 0;
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100225 mutex_init(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226
227 /* Default values in case the first read fails (unlikely). */
Jean Delvare709439a2005-09-25 16:41:18 +0200228 data->temp[1] = data->temp[0] = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
230 /* Tell the I2C layer a new client has arrived. */
231 if ((err = i2c_attach_client(new_client)))
232 goto exit_free;
233
234 /*
235 * Initialize the W83L785TS chip
236 * Nothing yet, assume it is already started.
237 */
238
239 /* Register sysfs hooks */
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400240 data->class_dev = hwmon_device_register(&new_client->dev);
241 if (IS_ERR(data->class_dev)) {
242 err = PTR_ERR(data->class_dev);
243 goto exit_detach;
244 }
245
Jean Delvare709439a2005-09-25 16:41:18 +0200246 device_create_file(&new_client->dev,
247 &sensor_dev_attr_temp1_input.dev_attr);
248 device_create_file(&new_client->dev,
249 &sensor_dev_attr_temp1_max.dev_attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
251 return 0;
252
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400253exit_detach:
254 i2c_detach_client(new_client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255exit_free:
256 kfree(data);
257exit:
258 return err;
259}
260
261static int w83l785ts_detach_client(struct i2c_client *client)
262{
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400263 struct w83l785ts_data *data = i2c_get_clientdata(client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 int err;
265
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400266 hwmon_device_unregister(data->class_dev);
267
Jean Delvare7bef5592005-07-27 22:14:49 +0200268 if ((err = i2c_detach_client(client)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400271 kfree(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 return 0;
273}
274
275static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
276{
277 int value, i;
278
279 /* Frequent read errors have been reported on Asus boards, so we
280 * retry on read errors. If it still fails (unlikely), return the
281 * default value requested by the caller. */
282 for (i = 1; i <= MAX_RETRIES; i++) {
283 value = i2c_smbus_read_byte_data(client, reg);
284 if (value >= 0) {
285 dev_dbg(&client->dev, "Read 0x%02x from register "
286 "0x%02x.\n", value, reg);
287 return value;
288 }
289 dev_dbg(&client->dev, "Read failed, will retry in %d.\n", i);
290 msleep(i);
291 }
292
293 dev_err(&client->dev, "Couldn't read value from register 0x%02x. "
294 "Please report.\n", reg);
295 return defval;
296}
297
298static struct w83l785ts_data *w83l785ts_update_device(struct device *dev)
299{
300 struct i2c_client *client = to_i2c_client(dev);
301 struct w83l785ts_data *data = i2c_get_clientdata(client);
302
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100303 mutex_lock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
305 if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) {
306 dev_dbg(&client->dev, "Updating w83l785ts data.\n");
Jean Delvare709439a2005-09-25 16:41:18 +0200307 data->temp[0] = w83l785ts_read_value(client,
308 W83L785TS_REG_TEMP, data->temp[0]);
309 data->temp[1] = w83l785ts_read_value(client,
310 W83L785TS_REG_TEMP_OVER, data->temp[1]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311
312 data->last_updated = jiffies;
313 data->valid = 1;
314 }
315
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100316 mutex_unlock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317
318 return data;
319}
320
321static int __init sensors_w83l785ts_init(void)
322{
323 return i2c_add_driver(&w83l785ts_driver);
324}
325
326static void __exit sensors_w83l785ts_exit(void)
327{
328 i2c_del_driver(&w83l785ts_driver);
329}
330
331MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
332MODULE_DESCRIPTION("W83L785TS-S driver");
333MODULE_LICENSE("GPL");
334
335module_init(sensors_w83l785ts_init);
336module_exit(sensors_w83l785ts_exit);