blob: f495b63786685ba72f77079bcdd361dde7bd18bf [file] [log] [blame]
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
43/* How many retries on register read error */
44#define MAX_RETRIES 5
45
46/*
47 * Address to scan
48 * Address is fully defined internally and cannot be changed.
49 */
50
51static unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
53/*
54 * Insmod parameters
55 */
56
Jean Delvaref4b50262005-07-31 21:49:03 +020057I2C_CLIENT_INSMOD_1(w83l785ts);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59/*
60 * The W83L785TS-S registers
61 * Manufacturer ID is 0x5CA3 for Winbond.
62 */
63
64#define W83L785TS_REG_MAN_ID1 0x4D
65#define W83L785TS_REG_MAN_ID2 0x4C
66#define W83L785TS_REG_CHIP_ID 0x4E
67#define W83L785TS_REG_CONFIG 0x40
68#define W83L785TS_REG_TYPE 0x52
69#define W83L785TS_REG_TEMP 0x27
70#define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */
71
72/*
73 * Conversions
74 * The W83L785TS-S uses signed 8-bit values.
75 */
76
Jean Delvarecb929ea2005-09-25 16:45:03 +020077#define TEMP_FROM_REG(val) ((val) * 1000)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79/*
80 * Functions declaration
81 */
82
83static int w83l785ts_attach_adapter(struct i2c_adapter *adapter);
84static int w83l785ts_detect(struct i2c_adapter *adapter, int address,
85 int kind);
86static int w83l785ts_detach_client(struct i2c_client *client);
87static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
88static struct w83l785ts_data *w83l785ts_update_device(struct device *dev);
89
90/*
91 * Driver data (common to all clients)
92 */
93
94static struct i2c_driver w83l785ts_driver = {
95 .owner = THIS_MODULE,
96 .name = "w83l785ts",
97 .id = I2C_DRIVERID_W83L785TS,
98 .flags = I2C_DF_NOTIFY,
99 .attach_adapter = w83l785ts_attach_adapter,
100 .detach_client = w83l785ts_detach_client,
101};
102
103/*
104 * Client data (each client gets its own)
105 */
106
107struct w83l785ts_data {
108 struct i2c_client client;
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400109 struct class_device *class_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 struct semaphore update_lock;
111 char valid; /* zero until following fields are valid */
112 unsigned long last_updated; /* in jiffies */
113
114 /* registers values */
Jean Delvarecb929ea2005-09-25 16:45:03 +0200115 s8 temp[2]; /* 0: input
Jean Delvare709439a2005-09-25 16:41:18 +0200116 1: critical limit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117};
118
119/*
120 * Sysfs stuff
121 */
122
Jean Delvare709439a2005-09-25 16:41:18 +0200123static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
124 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125{
Jean Delvare709439a2005-09-25 16:41:18 +0200126 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 struct w83l785ts_data *data = w83l785ts_update_device(dev);
Jean Delvare709439a2005-09-25 16:41:18 +0200128 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129}
130
Jean Delvare709439a2005-09-25 16:41:18 +0200131static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
132static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
134/*
135 * Real code
136 */
137
138static int w83l785ts_attach_adapter(struct i2c_adapter *adapter)
139{
140 if (!(adapter->class & I2C_CLASS_HWMON))
141 return 0;
Jean Delvare2ed2dc32005-07-31 21:42:02 +0200142 return i2c_probe(adapter, &addr_data, w83l785ts_detect);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143}
144
145/*
146 * The following function does more than just detection. If detection
147 * succeeds, it also registers the new chip.
148 */
149static int w83l785ts_detect(struct i2c_adapter *adapter, int address, int kind)
150{
151 struct i2c_client *new_client;
152 struct w83l785ts_data *data;
153 int err = 0;
154
155
156 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
157 goto exit;
158
Deepak Saxenaba9c2e82005-10-17 23:08:32 +0200159 if (!(data = kzalloc(sizeof(struct w83l785ts_data), GFP_KERNEL))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 err = -ENOMEM;
161 goto exit;
162 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
164 /* The common I2C client data is placed right before the
165 * W83L785TS-specific data. */
166 new_client = &data->client;
167 i2c_set_clientdata(new_client, data);
168 new_client->addr = address;
169 new_client->adapter = adapter;
170 new_client->driver = &w83l785ts_driver;
171 new_client->flags = 0;
172
173 /*
174 * Now we do the remaining detection. A negative kind means that
175 * the driver was loaded with no force parameter (default), so we
176 * must both detect and identify the chip (actually there is only
177 * one possible kind of chip for now, W83L785TS-S). A zero kind means
178 * that the driver was loaded with the force parameter, the detection
179 * step shall be skipped. A positive kind means that the driver
180 * was loaded with the force parameter and a given kind of chip is
181 * requested, so both the detection and the identification steps
182 * are skipped.
183 */
184 if (kind < 0) { /* detection */
185 if (((w83l785ts_read_value(new_client,
186 W83L785TS_REG_CONFIG, 0) & 0x80) != 0x00)
187 || ((w83l785ts_read_value(new_client,
188 W83L785TS_REG_TYPE, 0) & 0xFC) != 0x00)) {
189 dev_dbg(&adapter->dev,
190 "W83L785TS-S detection failed at 0x%02x.\n",
191 address);
192 goto exit_free;
193 }
194 }
195
196 if (kind <= 0) { /* identification */
197 u16 man_id;
198 u8 chip_id;
199
200 man_id = (w83l785ts_read_value(new_client,
201 W83L785TS_REG_MAN_ID1, 0) << 8) +
202 w83l785ts_read_value(new_client,
203 W83L785TS_REG_MAN_ID2, 0);
204 chip_id = w83l785ts_read_value(new_client,
205 W83L785TS_REG_CHIP_ID, 0);
206
207 if (man_id == 0x5CA3) { /* Winbond */
208 if (chip_id == 0x70) { /* W83L785TS-S */
209 kind = w83l785ts;
210 }
211 }
212
213 if (kind <= 0) { /* identification failed */
214 dev_info(&adapter->dev,
215 "Unsupported chip (man_id=0x%04X, "
216 "chip_id=0x%02X).\n", man_id, chip_id);
217 goto exit_free;
218 }
219 }
220
221 /* We can fill in the remaining client fields. */
222 strlcpy(new_client->name, "w83l785ts", I2C_NAME_SIZE);
223 data->valid = 0;
224 init_MUTEX(&data->update_lock);
225
226 /* Default values in case the first read fails (unlikely). */
Jean Delvare709439a2005-09-25 16:41:18 +0200227 data->temp[1] = data->temp[0] = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228
229 /* Tell the I2C layer a new client has arrived. */
230 if ((err = i2c_attach_client(new_client)))
231 goto exit_free;
232
233 /*
234 * Initialize the W83L785TS chip
235 * Nothing yet, assume it is already started.
236 */
237
238 /* Register sysfs hooks */
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400239 data->class_dev = hwmon_device_register(&new_client->dev);
240 if (IS_ERR(data->class_dev)) {
241 err = PTR_ERR(data->class_dev);
242 goto exit_detach;
243 }
244
Jean Delvare709439a2005-09-25 16:41:18 +0200245 device_create_file(&new_client->dev,
246 &sensor_dev_attr_temp1_input.dev_attr);
247 device_create_file(&new_client->dev,
248 &sensor_dev_attr_temp1_max.dev_attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249
250 return 0;
251
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400252exit_detach:
253 i2c_detach_client(new_client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254exit_free:
255 kfree(data);
256exit:
257 return err;
258}
259
260static int w83l785ts_detach_client(struct i2c_client *client)
261{
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400262 struct w83l785ts_data *data = i2c_get_clientdata(client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 int err;
264
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400265 hwmon_device_unregister(data->class_dev);
266
Jean Delvare7bef5592005-07-27 22:14:49 +0200267 if ((err = i2c_detach_client(client)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400270 kfree(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 return 0;
272}
273
274static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
275{
276 int value, i;
277
278 /* Frequent read errors have been reported on Asus boards, so we
279 * retry on read errors. If it still fails (unlikely), return the
280 * default value requested by the caller. */
281 for (i = 1; i <= MAX_RETRIES; i++) {
282 value = i2c_smbus_read_byte_data(client, reg);
283 if (value >= 0) {
284 dev_dbg(&client->dev, "Read 0x%02x from register "
285 "0x%02x.\n", value, reg);
286 return value;
287 }
288 dev_dbg(&client->dev, "Read failed, will retry in %d.\n", i);
289 msleep(i);
290 }
291
292 dev_err(&client->dev, "Couldn't read value from register 0x%02x. "
293 "Please report.\n", reg);
294 return defval;
295}
296
297static struct w83l785ts_data *w83l785ts_update_device(struct device *dev)
298{
299 struct i2c_client *client = to_i2c_client(dev);
300 struct w83l785ts_data *data = i2c_get_clientdata(client);
301
302 down(&data->update_lock);
303
304 if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) {
305 dev_dbg(&client->dev, "Updating w83l785ts data.\n");
Jean Delvare709439a2005-09-25 16:41:18 +0200306 data->temp[0] = w83l785ts_read_value(client,
307 W83L785TS_REG_TEMP, data->temp[0]);
308 data->temp[1] = w83l785ts_read_value(client,
309 W83L785TS_REG_TEMP_OVER, data->temp[1]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310
311 data->last_updated = jiffies;
312 data->valid = 1;
313 }
314
315 up(&data->update_lock);
316
317 return data;
318}
319
320static int __init sensors_w83l785ts_init(void)
321{
322 return i2c_add_driver(&w83l785ts_driver);
323}
324
325static void __exit sensors_w83l785ts_exit(void)
326{
327 i2c_del_driver(&w83l785ts_driver);
328}
329
330MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
331MODULE_DESCRIPTION("W83L785TS-S driver");
332MODULE_LICENSE("GPL");
333
334module_init(sensors_w83l785ts_init);
335module_exit(sensors_w83l785ts_exit);