diff options
Diffstat (limited to 'drivers/i2c/chips/ds1621.c')
-rw-r--r-- | drivers/i2c/chips/ds1621.c | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/drivers/i2c/chips/ds1621.c b/drivers/i2c/chips/ds1621.c new file mode 100644 index 000000000000..bb1fefb2162e --- /dev/null +++ b/drivers/i2c/chips/ds1621.c | |||
@@ -0,0 +1,341 @@ | |||
1 | /* | ||
2 | ds1621.c - Part of lm_sensors, Linux kernel modules for hardware | ||
3 | monitoring | ||
4 | Christian W. Zuckschwerdt <zany@triq.net> 2000-11-23 | ||
5 | based on lm75.c by Frodo Looijaard <frodol@dds.nl> | ||
6 | Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with | ||
7 | the help of Jean Delvare <khali@linux-fr.org> | ||
8 | |||
9 | This program is free software; you can redistribute it and/or modify | ||
10 | it under the terms of the GNU General Public License as published by | ||
11 | the Free Software Foundation; either version 2 of the License, or | ||
12 | (at your option) any later version. | ||
13 | |||
14 | This program is distributed in the hope that it will be useful, | ||
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
17 | GNU General Public License for more details. | ||
18 | |||
19 | You should have received a copy of the GNU General Public License | ||
20 | along with this program; if not, write to the Free Software | ||
21 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
22 | */ | ||
23 | |||
24 | #include <linux/module.h> | ||
25 | #include <linux/init.h> | ||
26 | #include <linux/slab.h> | ||
27 | #include <linux/jiffies.h> | ||
28 | #include <linux/i2c.h> | ||
29 | #include <linux/i2c-sensor.h> | ||
30 | #include "lm75.h" | ||
31 | |||
32 | /* Addresses to scan */ | ||
33 | static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c, | ||
34 | 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; | ||
35 | static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END }; | ||
36 | |||
37 | /* Insmod parameters */ | ||
38 | SENSORS_INSMOD_1(ds1621); | ||
39 | static int polarity = -1; | ||
40 | module_param(polarity, int, 0); | ||
41 | MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low"); | ||
42 | |||
43 | /* Many DS1621 constants specified below */ | ||
44 | /* Config register used for detection */ | ||
45 | /* 7 6 5 4 3 2 1 0 */ | ||
46 | /* |Done|THF |TLF |NVB | X | X |POL |1SHOT| */ | ||
47 | #define DS1621_REG_CONFIG_NVB 0x10 | ||
48 | #define DS1621_REG_CONFIG_POLARITY 0x02 | ||
49 | #define DS1621_REG_CONFIG_1SHOT 0x01 | ||
50 | #define DS1621_REG_CONFIG_DONE 0x80 | ||
51 | |||
52 | /* The DS1621 registers */ | ||
53 | #define DS1621_REG_TEMP 0xAA /* word, RO */ | ||
54 | #define DS1621_REG_TEMP_MIN 0xA1 /* word, RW */ | ||
55 | #define DS1621_REG_TEMP_MAX 0xA2 /* word, RW */ | ||
56 | #define DS1621_REG_CONF 0xAC /* byte, RW */ | ||
57 | #define DS1621_COM_START 0xEE /* no data */ | ||
58 | #define DS1621_COM_STOP 0x22 /* no data */ | ||
59 | |||
60 | /* The DS1621 configuration register */ | ||
61 | #define DS1621_ALARM_TEMP_HIGH 0x40 | ||
62 | #define DS1621_ALARM_TEMP_LOW 0x20 | ||
63 | |||
64 | /* Conversions. Rounding and limit checking is only done on the TO_REG | ||
65 | variants. Note that you should be a bit careful with which arguments | ||
66 | these macros are called: arguments may be evaluated more than once. | ||
67 | Fixing this is just not worth it. */ | ||
68 | #define ALARMS_FROM_REG(val) ((val) & \ | ||
69 | (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW)) | ||
70 | |||
71 | /* Each client has this additional data */ | ||
72 | struct ds1621_data { | ||
73 | struct i2c_client client; | ||
74 | struct semaphore update_lock; | ||
75 | char valid; /* !=0 if following fields are valid */ | ||
76 | unsigned long last_updated; /* In jiffies */ | ||
77 | |||
78 | u16 temp, temp_min, temp_max; /* Register values, word */ | ||
79 | u8 conf; /* Register encoding, combined */ | ||
80 | }; | ||
81 | |||
82 | static int ds1621_attach_adapter(struct i2c_adapter *adapter); | ||
83 | static int ds1621_detect(struct i2c_adapter *adapter, int address, | ||
84 | int kind); | ||
85 | static void ds1621_init_client(struct i2c_client *client); | ||
86 | static int ds1621_detach_client(struct i2c_client *client); | ||
87 | static struct ds1621_data *ds1621_update_client(struct device *dev); | ||
88 | |||
89 | /* This is the driver that will be inserted */ | ||
90 | static struct i2c_driver ds1621_driver = { | ||
91 | .owner = THIS_MODULE, | ||
92 | .name = "ds1621", | ||
93 | .id = I2C_DRIVERID_DS1621, | ||
94 | .flags = I2C_DF_NOTIFY, | ||
95 | .attach_adapter = ds1621_attach_adapter, | ||
96 | .detach_client = ds1621_detach_client, | ||
97 | }; | ||
98 | |||
99 | /* All registers are word-sized, except for the configuration register. | ||
100 | DS1621 uses a high-byte first convention, which is exactly opposite to | ||
101 | the usual practice. */ | ||
102 | static int ds1621_read_value(struct i2c_client *client, u8 reg) | ||
103 | { | ||
104 | if (reg == DS1621_REG_CONF) | ||
105 | return i2c_smbus_read_byte_data(client, reg); | ||
106 | else | ||
107 | return swab16(i2c_smbus_read_word_data(client, reg)); | ||
108 | } | ||
109 | |||
110 | /* All registers are word-sized, except for the configuration register. | ||
111 | DS1621 uses a high-byte first convention, which is exactly opposite to | ||
112 | the usual practice. */ | ||
113 | static int ds1621_write_value(struct i2c_client *client, u8 reg, u16 value) | ||
114 | { | ||
115 | if (reg == DS1621_REG_CONF) | ||
116 | return i2c_smbus_write_byte_data(client, reg, value); | ||
117 | else | ||
118 | return i2c_smbus_write_word_data(client, reg, swab16(value)); | ||
119 | } | ||
120 | |||
121 | static void ds1621_init_client(struct i2c_client *client) | ||
122 | { | ||
123 | int reg = ds1621_read_value(client, DS1621_REG_CONF); | ||
124 | /* switch to continous conversion mode */ | ||
125 | reg &= ~ DS1621_REG_CONFIG_1SHOT; | ||
126 | |||
127 | /* setup output polarity */ | ||
128 | if (polarity == 0) | ||
129 | reg &= ~DS1621_REG_CONFIG_POLARITY; | ||
130 | else if (polarity == 1) | ||
131 | reg |= DS1621_REG_CONFIG_POLARITY; | ||
132 | |||
133 | ds1621_write_value(client, DS1621_REG_CONF, reg); | ||
134 | |||
135 | /* start conversion */ | ||
136 | i2c_smbus_write_byte(client, DS1621_COM_START); | ||
137 | } | ||
138 | |||
139 | #define show(value) \ | ||
140 | static ssize_t show_##value(struct device *dev, char *buf) \ | ||
141 | { \ | ||
142 | struct ds1621_data *data = ds1621_update_client(dev); \ | ||
143 | return sprintf(buf, "%d\n", LM75_TEMP_FROM_REG(data->value)); \ | ||
144 | } | ||
145 | |||
146 | show(temp); | ||
147 | show(temp_min); | ||
148 | show(temp_max); | ||
149 | |||
150 | #define set_temp(suffix, value, reg) \ | ||
151 | static ssize_t set_temp_##suffix(struct device *dev, const char *buf, \ | ||
152 | size_t count) \ | ||
153 | { \ | ||
154 | struct i2c_client *client = to_i2c_client(dev); \ | ||
155 | struct ds1621_data *data = ds1621_update_client(dev); \ | ||
156 | u16 val = LM75_TEMP_TO_REG(simple_strtoul(buf, NULL, 10)); \ | ||
157 | \ | ||
158 | down(&data->update_lock); \ | ||
159 | data->value = val; \ | ||
160 | ds1621_write_value(client, reg, data->value); \ | ||
161 | up(&data->update_lock); \ | ||
162 | return count; \ | ||
163 | } | ||
164 | |||
165 | set_temp(min, temp_min, DS1621_REG_TEMP_MIN); | ||
166 | set_temp(max, temp_max, DS1621_REG_TEMP_MAX); | ||
167 | |||
168 | static ssize_t show_alarms(struct device *dev, char *buf) | ||
169 | { | ||
170 | struct ds1621_data *data = ds1621_update_client(dev); | ||
171 | return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf)); | ||
172 | } | ||
173 | |||
174 | static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); | ||
175 | static DEVICE_ATTR(temp1_input, S_IRUGO , show_temp, NULL); | ||
176 | static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO , show_temp_min, set_temp_min); | ||
177 | static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max, set_temp_max); | ||
178 | |||
179 | |||
180 | static int ds1621_attach_adapter(struct i2c_adapter *adapter) | ||
181 | { | ||
182 | return i2c_detect(adapter, &addr_data, ds1621_detect); | ||
183 | } | ||
184 | |||
185 | /* This function is called by i2c_detect */ | ||
186 | int ds1621_detect(struct i2c_adapter *adapter, int address, | ||
187 | int kind) | ||
188 | { | ||
189 | int conf, temp; | ||
190 | struct i2c_client *new_client; | ||
191 | struct ds1621_data *data; | ||
192 | int err = 0; | ||
193 | |||
194 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | ||
195 | | I2C_FUNC_SMBUS_WORD_DATA | ||
196 | | I2C_FUNC_SMBUS_WRITE_BYTE)) | ||
197 | goto exit; | ||
198 | |||
199 | /* OK. For now, we presume we have a valid client. We now create the | ||
200 | client structure, even though we cannot fill it completely yet. | ||
201 | But it allows us to access ds1621_{read,write}_value. */ | ||
202 | if (!(data = kmalloc(sizeof(struct ds1621_data), GFP_KERNEL))) { | ||
203 | err = -ENOMEM; | ||
204 | goto exit; | ||
205 | } | ||
206 | memset(data, 0, sizeof(struct ds1621_data)); | ||
207 | |||
208 | new_client = &data->client; | ||
209 | i2c_set_clientdata(new_client, data); | ||
210 | new_client->addr = address; | ||
211 | new_client->adapter = adapter; | ||
212 | new_client->driver = &ds1621_driver; | ||
213 | new_client->flags = 0; | ||
214 | |||
215 | |||
216 | /* Now, we do the remaining detection. It is lousy. */ | ||
217 | if (kind < 0) { | ||
218 | /* The NVB bit should be low if no EEPROM write has been | ||
219 | requested during the latest 10ms, which is highly | ||
220 | improbable in our case. */ | ||
221 | conf = ds1621_read_value(new_client, DS1621_REG_CONF); | ||
222 | if (conf & DS1621_REG_CONFIG_NVB) | ||
223 | goto exit_free; | ||
224 | /* The 7 lowest bits of a temperature should always be 0. */ | ||
225 | temp = ds1621_read_value(new_client, DS1621_REG_TEMP); | ||
226 | if (temp & 0x007f) | ||
227 | goto exit_free; | ||
228 | temp = ds1621_read_value(new_client, DS1621_REG_TEMP_MIN); | ||
229 | if (temp & 0x007f) | ||
230 | goto exit_free; | ||
231 | temp = ds1621_read_value(new_client, DS1621_REG_TEMP_MAX); | ||
232 | if (temp & 0x007f) | ||
233 | goto exit_free; | ||
234 | } | ||
235 | |||
236 | /* Determine the chip type - only one kind supported! */ | ||
237 | if (kind <= 0) | ||
238 | kind = ds1621; | ||
239 | |||
240 | /* Fill in remaining client fields and put it into the global list */ | ||
241 | strlcpy(new_client->name, "ds1621", I2C_NAME_SIZE); | ||
242 | data->valid = 0; | ||
243 | init_MUTEX(&data->update_lock); | ||
244 | |||
245 | /* Tell the I2C layer a new client has arrived */ | ||
246 | if ((err = i2c_attach_client(new_client))) | ||
247 | goto exit_free; | ||
248 | |||
249 | /* Initialize the DS1621 chip */ | ||
250 | ds1621_init_client(new_client); | ||
251 | |||
252 | /* Register sysfs hooks */ | ||
253 | device_create_file(&new_client->dev, &dev_attr_alarms); | ||
254 | device_create_file(&new_client->dev, &dev_attr_temp1_input); | ||
255 | device_create_file(&new_client->dev, &dev_attr_temp1_min); | ||
256 | device_create_file(&new_client->dev, &dev_attr_temp1_max); | ||
257 | |||
258 | return 0; | ||
259 | |||
260 | /* OK, this is not exactly good programming practice, usually. But it is | ||
261 | very code-efficient in this case. */ | ||
262 | exit_free: | ||
263 | kfree(data); | ||
264 | exit: | ||
265 | return err; | ||
266 | } | ||
267 | |||
268 | static int ds1621_detach_client(struct i2c_client *client) | ||
269 | { | ||
270 | int err; | ||
271 | |||
272 | if ((err = i2c_detach_client(client))) { | ||
273 | dev_err(&client->dev, "Client deregistration failed, " | ||
274 | "client not detached.\n"); | ||
275 | return err; | ||
276 | } | ||
277 | |||
278 | kfree(i2c_get_clientdata(client)); | ||
279 | |||
280 | return 0; | ||
281 | } | ||
282 | |||
283 | |||
284 | static struct ds1621_data *ds1621_update_client(struct device *dev) | ||
285 | { | ||
286 | struct i2c_client *client = to_i2c_client(dev); | ||
287 | struct ds1621_data *data = i2c_get_clientdata(client); | ||
288 | u8 new_conf; | ||
289 | |||
290 | down(&data->update_lock); | ||
291 | |||
292 | if (time_after(jiffies, data->last_updated + HZ + HZ / 2) | ||
293 | || !data->valid) { | ||
294 | |||
295 | dev_dbg(&client->dev, "Starting ds1621 update\n"); | ||
296 | |||
297 | data->conf = ds1621_read_value(client, DS1621_REG_CONF); | ||
298 | |||
299 | data->temp = ds1621_read_value(client, DS1621_REG_TEMP); | ||
300 | |||
301 | data->temp_min = ds1621_read_value(client, | ||
302 | DS1621_REG_TEMP_MIN); | ||
303 | data->temp_max = ds1621_read_value(client, | ||
304 | DS1621_REG_TEMP_MAX); | ||
305 | |||
306 | /* reset alarms if neccessary */ | ||
307 | new_conf = data->conf; | ||
308 | if (data->temp < data->temp_min) | ||
309 | new_conf &= ~DS1621_ALARM_TEMP_LOW; | ||
310 | if (data->temp > data->temp_max) | ||
311 | new_conf &= ~DS1621_ALARM_TEMP_HIGH; | ||
312 | if (data->conf != new_conf) | ||
313 | ds1621_write_value(client, DS1621_REG_CONF, | ||
314 | new_conf); | ||
315 | |||
316 | data->last_updated = jiffies; | ||
317 | data->valid = 1; | ||
318 | } | ||
319 | |||
320 | up(&data->update_lock); | ||
321 | |||
322 | return data; | ||
323 | } | ||
324 | |||
325 | static int __init ds1621_init(void) | ||
326 | { | ||
327 | return i2c_add_driver(&ds1621_driver); | ||
328 | } | ||
329 | |||
330 | static void __exit ds1621_exit(void) | ||
331 | { | ||
332 | i2c_del_driver(&ds1621_driver); | ||
333 | } | ||
334 | |||
335 | |||
336 | MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>"); | ||
337 | MODULE_DESCRIPTION("DS1621 driver"); | ||
338 | MODULE_LICENSE("GPL"); | ||
339 | |||
340 | module_init(ds1621_init); | ||
341 | module_exit(ds1621_exit); | ||