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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>
40#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42/* How many retries on register read error */
43#define MAX_RETRIES 5
44
45/*
46 * Address to scan
47 * Address is fully defined internally and cannot be changed.
48 */
49
50static unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
52/*
53 * Insmod parameters
54 */
55
Jean Delvaref4b50262005-07-31 21:49:03 +020056I2C_CLIENT_INSMOD_1(w83l785ts);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58/*
59 * The W83L785TS-S registers
60 * Manufacturer ID is 0x5CA3 for Winbond.
61 */
62
63#define W83L785TS_REG_MAN_ID1 0x4D
64#define W83L785TS_REG_MAN_ID2 0x4C
65#define W83L785TS_REG_CHIP_ID 0x4E
66#define W83L785TS_REG_CONFIG 0x40
67#define W83L785TS_REG_TYPE 0x52
68#define W83L785TS_REG_TEMP 0x27
69#define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */
70
71/*
72 * Conversions
73 * The W83L785TS-S uses signed 8-bit values.
74 */
75
76#define TEMP_FROM_REG(val) ((val & 0x80 ? val-0x100 : val) * 1000)
77
78/*
79 * Functions declaration
80 */
81
82static int w83l785ts_attach_adapter(struct i2c_adapter *adapter);
83static int w83l785ts_detect(struct i2c_adapter *adapter, int address,
84 int kind);
85static int w83l785ts_detach_client(struct i2c_client *client);
86static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
87static struct w83l785ts_data *w83l785ts_update_device(struct device *dev);
88
89/*
90 * Driver data (common to all clients)
91 */
92
93static struct i2c_driver w83l785ts_driver = {
94 .owner = THIS_MODULE,
95 .name = "w83l785ts",
96 .id = I2C_DRIVERID_W83L785TS,
97 .flags = I2C_DF_NOTIFY,
98 .attach_adapter = w83l785ts_attach_adapter,
99 .detach_client = w83l785ts_detach_client,
100};
101
102/*
103 * Client data (each client gets its own)
104 */
105
106struct w83l785ts_data {
107 struct i2c_client client;
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400108 struct class_device *class_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 struct semaphore update_lock;
110 char valid; /* zero until following fields are valid */
111 unsigned long last_updated; /* in jiffies */
112
113 /* registers values */
114 u8 temp, temp_over;
115};
116
117/*
118 * Sysfs stuff
119 */
120
Yani Ioannoue404e272005-05-17 06:42:58 -0400121static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122{
123 struct w83l785ts_data *data = w83l785ts_update_device(dev);
124 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));
125}
126
Yani Ioannoue404e272005-05-17 06:42:58 -0400127static ssize_t show_temp_over(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128{
129 struct w83l785ts_data *data = w83l785ts_update_device(dev);
130 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over));
131}
132
133static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
134static DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_over, NULL);
135
136/*
137 * Real code
138 */
139
140static int w83l785ts_attach_adapter(struct i2c_adapter *adapter)
141{
142 if (!(adapter->class & I2C_CLASS_HWMON))
143 return 0;
Jean Delvare2ed2dc32005-07-31 21:42:02 +0200144 return i2c_probe(adapter, &addr_data, w83l785ts_detect);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145}
146
147/*
148 * The following function does more than just detection. If detection
149 * succeeds, it also registers the new chip.
150 */
151static int w83l785ts_detect(struct i2c_adapter *adapter, int address, int kind)
152{
153 struct i2c_client *new_client;
154 struct w83l785ts_data *data;
155 int err = 0;
156
157
158 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
159 goto exit;
160
161 if (!(data = kmalloc(sizeof(struct w83l785ts_data), GFP_KERNEL))) {
162 err = -ENOMEM;
163 goto exit;
164 }
165 memset(data, 0, sizeof(struct w83l785ts_data));
166
167
168 /* The common I2C client data is placed right before the
169 * W83L785TS-specific data. */
170 new_client = &data->client;
171 i2c_set_clientdata(new_client, data);
172 new_client->addr = address;
173 new_client->adapter = adapter;
174 new_client->driver = &w83l785ts_driver;
175 new_client->flags = 0;
176
177 /*
178 * Now we do the remaining detection. A negative kind means that
179 * the driver was loaded with no force parameter (default), so we
180 * must both detect and identify the chip (actually there is only
181 * one possible kind of chip for now, W83L785TS-S). A zero kind means
182 * that the driver was loaded with the force parameter, the detection
183 * step shall be skipped. A positive kind means that the driver
184 * was loaded with the force parameter and a given kind of chip is
185 * requested, so both the detection and the identification steps
186 * are skipped.
187 */
188 if (kind < 0) { /* detection */
189 if (((w83l785ts_read_value(new_client,
190 W83L785TS_REG_CONFIG, 0) & 0x80) != 0x00)
191 || ((w83l785ts_read_value(new_client,
192 W83L785TS_REG_TYPE, 0) & 0xFC) != 0x00)) {
193 dev_dbg(&adapter->dev,
194 "W83L785TS-S detection failed at 0x%02x.\n",
195 address);
196 goto exit_free;
197 }
198 }
199
200 if (kind <= 0) { /* identification */
201 u16 man_id;
202 u8 chip_id;
203
204 man_id = (w83l785ts_read_value(new_client,
205 W83L785TS_REG_MAN_ID1, 0) << 8) +
206 w83l785ts_read_value(new_client,
207 W83L785TS_REG_MAN_ID2, 0);
208 chip_id = w83l785ts_read_value(new_client,
209 W83L785TS_REG_CHIP_ID, 0);
210
211 if (man_id == 0x5CA3) { /* Winbond */
212 if (chip_id == 0x70) { /* W83L785TS-S */
213 kind = w83l785ts;
214 }
215 }
216
217 if (kind <= 0) { /* identification failed */
218 dev_info(&adapter->dev,
219 "Unsupported chip (man_id=0x%04X, "
220 "chip_id=0x%02X).\n", man_id, chip_id);
221 goto exit_free;
222 }
223 }
224
225 /* We can fill in the remaining client fields. */
226 strlcpy(new_client->name, "w83l785ts", I2C_NAME_SIZE);
227 data->valid = 0;
228 init_MUTEX(&data->update_lock);
229
230 /* Default values in case the first read fails (unlikely). */
231 data->temp_over = data->temp = 0;
232
233 /* Tell the I2C layer a new client has arrived. */
234 if ((err = i2c_attach_client(new_client)))
235 goto exit_free;
236
237 /*
238 * Initialize the W83L785TS chip
239 * Nothing yet, assume it is already started.
240 */
241
242 /* Register sysfs hooks */
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400243 data->class_dev = hwmon_device_register(&new_client->dev);
244 if (IS_ERR(data->class_dev)) {
245 err = PTR_ERR(data->class_dev);
246 goto exit_detach;
247 }
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 device_create_file(&new_client->dev, &dev_attr_temp1_input);
250 device_create_file(&new_client->dev, &dev_attr_temp1_max);
251
252 return 0;
253
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400254exit_detach:
255 i2c_detach_client(new_client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256exit_free:
257 kfree(data);
258exit:
259 return err;
260}
261
262static int w83l785ts_detach_client(struct i2c_client *client)
263{
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400264 struct w83l785ts_data *data = i2c_get_clientdata(client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 int err;
266
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400267 hwmon_device_unregister(data->class_dev);
268
Jean Delvare7bef5592005-07-27 22:14:49 +0200269 if ((err = i2c_detach_client(client)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400272 kfree(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 return 0;
274}
275
276static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
277{
278 int value, i;
279
280 /* Frequent read errors have been reported on Asus boards, so we
281 * retry on read errors. If it still fails (unlikely), return the
282 * default value requested by the caller. */
283 for (i = 1; i <= MAX_RETRIES; i++) {
284 value = i2c_smbus_read_byte_data(client, reg);
285 if (value >= 0) {
286 dev_dbg(&client->dev, "Read 0x%02x from register "
287 "0x%02x.\n", value, reg);
288 return value;
289 }
290 dev_dbg(&client->dev, "Read failed, will retry in %d.\n", i);
291 msleep(i);
292 }
293
294 dev_err(&client->dev, "Couldn't read value from register 0x%02x. "
295 "Please report.\n", reg);
296 return defval;
297}
298
299static struct w83l785ts_data *w83l785ts_update_device(struct device *dev)
300{
301 struct i2c_client *client = to_i2c_client(dev);
302 struct w83l785ts_data *data = i2c_get_clientdata(client);
303
304 down(&data->update_lock);
305
306 if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) {
307 dev_dbg(&client->dev, "Updating w83l785ts data.\n");
308 data->temp = w83l785ts_read_value(client,
309 W83L785TS_REG_TEMP, data->temp);
310 data->temp_over = w83l785ts_read_value(client,
311 W83L785TS_REG_TEMP_OVER, data->temp_over);
312
313 data->last_updated = jiffies;
314 data->valid = 1;
315 }
316
317 up(&data->update_lock);
318
319 return data;
320}
321
322static int __init sensors_w83l785ts_init(void)
323{
324 return i2c_add_driver(&w83l785ts_driver);
325}
326
327static void __exit sensors_w83l785ts_exit(void)
328{
329 i2c_del_driver(&w83l785ts_driver);
330}
331
332MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
333MODULE_DESCRIPTION("W83L785TS-S driver");
334MODULE_LICENSE("GPL");
335
336module_init(sensors_w83l785ts_init);
337module_exit(sensors_w83l785ts_exit);