1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com> |
4 | * |
5 | * The LM95241 is a sensor chip made by National Semiconductors. |
6 | * It reports up to three temperatures (its own plus up to two external ones). |
7 | * Complete datasheet can be obtained from National's website at: |
8 | * http://www.national.com/ds.cgi/LM/LM95241.pdf |
9 | */ |
10 | |
11 | #include <linux/bitops.h> |
12 | #include <linux/err.h> |
13 | #include <linux/i2c.h> |
14 | #include <linux/init.h> |
15 | #include <linux/jiffies.h> |
16 | #include <linux/hwmon.h> |
17 | #include <linux/module.h> |
18 | #include <linux/mutex.h> |
19 | #include <linux/slab.h> |
20 | |
21 | #define DEVNAME "lm95241" |
22 | |
23 | static const unsigned short normal_i2c[] = { |
24 | 0x19, 0x2a, 0x2b, I2C_CLIENT_END }; |
25 | |
26 | /* LM95241 registers */ |
27 | #define LM95241_REG_R_MAN_ID 0xFE |
28 | #define LM95241_REG_R_CHIP_ID 0xFF |
29 | #define LM95241_REG_R_STATUS 0x02 |
30 | #define LM95241_REG_RW_CONFIG 0x03 |
31 | #define LM95241_REG_RW_REM_FILTER 0x06 |
32 | #define LM95241_REG_RW_TRUTHERM 0x07 |
33 | #define LM95241_REG_W_ONE_SHOT 0x0F |
34 | #define LM95241_REG_R_LOCAL_TEMPH 0x10 |
35 | #define LM95241_REG_R_REMOTE1_TEMPH 0x11 |
36 | #define LM95241_REG_R_REMOTE2_TEMPH 0x12 |
37 | #define LM95241_REG_R_LOCAL_TEMPL 0x20 |
38 | #define LM95241_REG_R_REMOTE1_TEMPL 0x21 |
39 | #define LM95241_REG_R_REMOTE2_TEMPL 0x22 |
40 | #define LM95241_REG_RW_REMOTE_MODEL 0x30 |
41 | |
42 | /* LM95241 specific bitfields */ |
43 | #define CFG_STOP BIT(6) |
44 | #define CFG_CR0076 0x00 |
45 | #define CFG_CR0182 BIT(4) |
46 | #define CFG_CR1000 BIT(5) |
47 | #define CFG_CR2700 (BIT(4) | BIT(5)) |
48 | #define CFG_CRMASK (BIT(4) | BIT(5)) |
49 | #define R1MS_MASK BIT(0) |
50 | #define R2MS_MASK BIT(2) |
51 | #define R1DF_MASK BIT(1) |
52 | #define R2DF_MASK BIT(2) |
53 | #define R1FE_MASK BIT(0) |
54 | #define R2FE_MASK BIT(2) |
55 | #define R1DM BIT(0) |
56 | #define R2DM BIT(1) |
57 | #define TT1_SHIFT 0 |
58 | #define TT2_SHIFT 4 |
59 | #define TT_OFF 0 |
60 | #define TT_ON 1 |
61 | #define TT_MASK 7 |
62 | #define NATSEMI_MAN_ID 0x01 |
63 | #define LM95231_CHIP_ID 0xA1 |
64 | #define LM95241_CHIP_ID 0xA4 |
65 | |
66 | static const u8 lm95241_reg_address[] = { |
67 | LM95241_REG_R_LOCAL_TEMPH, |
68 | LM95241_REG_R_LOCAL_TEMPL, |
69 | LM95241_REG_R_REMOTE1_TEMPH, |
70 | LM95241_REG_R_REMOTE1_TEMPL, |
71 | LM95241_REG_R_REMOTE2_TEMPH, |
72 | LM95241_REG_R_REMOTE2_TEMPL |
73 | }; |
74 | |
75 | /* Client data (each client gets its own) */ |
76 | struct lm95241_data { |
77 | struct i2c_client *client; |
78 | struct mutex update_lock; |
79 | unsigned long last_updated; /* in jiffies */ |
80 | unsigned long interval; /* in milli-seconds */ |
81 | bool valid; /* false until following fields are valid */ |
82 | /* registers values */ |
83 | u8 temp[ARRAY_SIZE(lm95241_reg_address)]; |
84 | u8 status, config, model, trutherm; |
85 | }; |
86 | |
87 | /* Conversions */ |
88 | static int temp_from_reg_signed(u8 val_h, u8 val_l) |
89 | { |
90 | s16 val_hl = (val_h << 8) | val_l; |
91 | return val_hl * 1000 / 256; |
92 | } |
93 | |
94 | static int temp_from_reg_unsigned(u8 val_h, u8 val_l) |
95 | { |
96 | u16 val_hl = (val_h << 8) | val_l; |
97 | return val_hl * 1000 / 256; |
98 | } |
99 | |
100 | static struct lm95241_data *lm95241_update_device(struct device *dev) |
101 | { |
102 | struct lm95241_data *data = dev_get_drvdata(dev); |
103 | struct i2c_client *client = data->client; |
104 | |
105 | mutex_lock(&data->update_lock); |
106 | |
107 | if (time_after(jiffies, data->last_updated |
108 | + msecs_to_jiffies(data->interval)) || |
109 | !data->valid) { |
110 | int i; |
111 | |
112 | dev_dbg(dev, "Updating lm95241 data.\n" ); |
113 | for (i = 0; i < ARRAY_SIZE(lm95241_reg_address); i++) |
114 | data->temp[i] |
115 | = i2c_smbus_read_byte_data(client, |
116 | command: lm95241_reg_address[i]); |
117 | |
118 | data->status = i2c_smbus_read_byte_data(client, |
119 | LM95241_REG_R_STATUS); |
120 | data->last_updated = jiffies; |
121 | data->valid = true; |
122 | } |
123 | |
124 | mutex_unlock(lock: &data->update_lock); |
125 | |
126 | return data; |
127 | } |
128 | |
129 | static int lm95241_read_chip(struct device *dev, u32 attr, int channel, |
130 | long *val) |
131 | { |
132 | struct lm95241_data *data = dev_get_drvdata(dev); |
133 | |
134 | switch (attr) { |
135 | case hwmon_chip_update_interval: |
136 | *val = data->interval; |
137 | return 0; |
138 | default: |
139 | return -EOPNOTSUPP; |
140 | } |
141 | } |
142 | |
143 | static int lm95241_read_temp(struct device *dev, u32 attr, int channel, |
144 | long *val) |
145 | { |
146 | struct lm95241_data *data = lm95241_update_device(dev); |
147 | |
148 | switch (attr) { |
149 | case hwmon_temp_input: |
150 | if (!channel || (data->config & BIT(channel - 1))) |
151 | *val = temp_from_reg_signed(val_h: data->temp[channel * 2], |
152 | val_l: data->temp[channel * 2 + 1]); |
153 | else |
154 | *val = temp_from_reg_unsigned(val_h: data->temp[channel * 2], |
155 | val_l: data->temp[channel * 2 + 1]); |
156 | return 0; |
157 | case hwmon_temp_min: |
158 | if (channel == 1) |
159 | *val = (data->config & R1DF_MASK) ? -128000 : 0; |
160 | else |
161 | *val = (data->config & R2DF_MASK) ? -128000 : 0; |
162 | return 0; |
163 | case hwmon_temp_max: |
164 | if (channel == 1) |
165 | *val = (data->config & R1DF_MASK) ? 127875 : 255875; |
166 | else |
167 | *val = (data->config & R2DF_MASK) ? 127875 : 255875; |
168 | return 0; |
169 | case hwmon_temp_type: |
170 | if (channel == 1) |
171 | *val = (data->model & R1MS_MASK) ? 1 : 2; |
172 | else |
173 | *val = (data->model & R2MS_MASK) ? 1 : 2; |
174 | return 0; |
175 | case hwmon_temp_fault: |
176 | if (channel == 1) |
177 | *val = !!(data->status & R1DM); |
178 | else |
179 | *val = !!(data->status & R2DM); |
180 | return 0; |
181 | default: |
182 | return -EOPNOTSUPP; |
183 | } |
184 | } |
185 | |
186 | static int lm95241_read(struct device *dev, enum hwmon_sensor_types type, |
187 | u32 attr, int channel, long *val) |
188 | { |
189 | switch (type) { |
190 | case hwmon_chip: |
191 | return lm95241_read_chip(dev, attr, channel, val); |
192 | case hwmon_temp: |
193 | return lm95241_read_temp(dev, attr, channel, val); |
194 | default: |
195 | return -EOPNOTSUPP; |
196 | } |
197 | } |
198 | |
199 | static int lm95241_write_chip(struct device *dev, u32 attr, int channel, |
200 | long val) |
201 | { |
202 | struct lm95241_data *data = dev_get_drvdata(dev); |
203 | int convrate; |
204 | u8 config; |
205 | int ret; |
206 | |
207 | mutex_lock(&data->update_lock); |
208 | |
209 | switch (attr) { |
210 | case hwmon_chip_update_interval: |
211 | config = data->config & ~CFG_CRMASK; |
212 | if (val < 130) { |
213 | convrate = 76; |
214 | config |= CFG_CR0076; |
215 | } else if (val < 590) { |
216 | convrate = 182; |
217 | config |= CFG_CR0182; |
218 | } else if (val < 1850) { |
219 | convrate = 1000; |
220 | config |= CFG_CR1000; |
221 | } else { |
222 | convrate = 2700; |
223 | config |= CFG_CR2700; |
224 | } |
225 | data->interval = convrate; |
226 | data->config = config; |
227 | ret = i2c_smbus_write_byte_data(client: data->client, |
228 | LM95241_REG_RW_CONFIG, value: config); |
229 | break; |
230 | default: |
231 | ret = -EOPNOTSUPP; |
232 | break; |
233 | } |
234 | mutex_unlock(lock: &data->update_lock); |
235 | return ret; |
236 | } |
237 | |
238 | static int lm95241_write_temp(struct device *dev, u32 attr, int channel, |
239 | long val) |
240 | { |
241 | struct lm95241_data *data = dev_get_drvdata(dev); |
242 | struct i2c_client *client = data->client; |
243 | int ret; |
244 | |
245 | mutex_lock(&data->update_lock); |
246 | |
247 | switch (attr) { |
248 | case hwmon_temp_min: |
249 | if (channel == 1) { |
250 | if (val < 0) |
251 | data->config |= R1DF_MASK; |
252 | else |
253 | data->config &= ~R1DF_MASK; |
254 | } else { |
255 | if (val < 0) |
256 | data->config |= R2DF_MASK; |
257 | else |
258 | data->config &= ~R2DF_MASK; |
259 | } |
260 | data->valid = false; |
261 | ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, |
262 | value: data->config); |
263 | break; |
264 | case hwmon_temp_max: |
265 | if (channel == 1) { |
266 | if (val <= 127875) |
267 | data->config |= R1DF_MASK; |
268 | else |
269 | data->config &= ~R1DF_MASK; |
270 | } else { |
271 | if (val <= 127875) |
272 | data->config |= R2DF_MASK; |
273 | else |
274 | data->config &= ~R2DF_MASK; |
275 | } |
276 | data->valid = false; |
277 | ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, |
278 | value: data->config); |
279 | break; |
280 | case hwmon_temp_type: |
281 | if (val != 1 && val != 2) { |
282 | ret = -EINVAL; |
283 | break; |
284 | } |
285 | if (channel == 1) { |
286 | data->trutherm &= ~(TT_MASK << TT1_SHIFT); |
287 | if (val == 1) { |
288 | data->model |= R1MS_MASK; |
289 | data->trutherm |= (TT_ON << TT1_SHIFT); |
290 | } else { |
291 | data->model &= ~R1MS_MASK; |
292 | data->trutherm |= (TT_OFF << TT1_SHIFT); |
293 | } |
294 | } else { |
295 | data->trutherm &= ~(TT_MASK << TT2_SHIFT); |
296 | if (val == 1) { |
297 | data->model |= R2MS_MASK; |
298 | data->trutherm |= (TT_ON << TT2_SHIFT); |
299 | } else { |
300 | data->model &= ~R2MS_MASK; |
301 | data->trutherm |= (TT_OFF << TT2_SHIFT); |
302 | } |
303 | } |
304 | ret = i2c_smbus_write_byte_data(client, |
305 | LM95241_REG_RW_REMOTE_MODEL, |
306 | value: data->model); |
307 | if (ret < 0) |
308 | break; |
309 | ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, |
310 | value: data->trutherm); |
311 | break; |
312 | default: |
313 | ret = -EOPNOTSUPP; |
314 | break; |
315 | } |
316 | |
317 | mutex_unlock(lock: &data->update_lock); |
318 | |
319 | return ret; |
320 | } |
321 | |
322 | static int lm95241_write(struct device *dev, enum hwmon_sensor_types type, |
323 | u32 attr, int channel, long val) |
324 | { |
325 | switch (type) { |
326 | case hwmon_chip: |
327 | return lm95241_write_chip(dev, attr, channel, val); |
328 | case hwmon_temp: |
329 | return lm95241_write_temp(dev, attr, channel, val); |
330 | default: |
331 | return -EOPNOTSUPP; |
332 | } |
333 | } |
334 | |
335 | static umode_t lm95241_is_visible(const void *data, |
336 | enum hwmon_sensor_types type, |
337 | u32 attr, int channel) |
338 | { |
339 | switch (type) { |
340 | case hwmon_chip: |
341 | switch (attr) { |
342 | case hwmon_chip_update_interval: |
343 | return 0644; |
344 | } |
345 | break; |
346 | case hwmon_temp: |
347 | switch (attr) { |
348 | case hwmon_temp_input: |
349 | return 0444; |
350 | case hwmon_temp_fault: |
351 | return 0444; |
352 | case hwmon_temp_min: |
353 | case hwmon_temp_max: |
354 | case hwmon_temp_type: |
355 | return 0644; |
356 | } |
357 | break; |
358 | default: |
359 | break; |
360 | } |
361 | return 0; |
362 | } |
363 | |
364 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
365 | static int lm95241_detect(struct i2c_client *new_client, |
366 | struct i2c_board_info *info) |
367 | { |
368 | struct i2c_adapter *adapter = new_client->adapter; |
369 | const char *name; |
370 | int mfg_id, chip_id; |
371 | |
372 | if (!i2c_check_functionality(adap: adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
373 | return -ENODEV; |
374 | |
375 | mfg_id = i2c_smbus_read_byte_data(client: new_client, LM95241_REG_R_MAN_ID); |
376 | if (mfg_id != NATSEMI_MAN_ID) |
377 | return -ENODEV; |
378 | |
379 | chip_id = i2c_smbus_read_byte_data(client: new_client, LM95241_REG_R_CHIP_ID); |
380 | switch (chip_id) { |
381 | case LM95231_CHIP_ID: |
382 | name = "lm95231" ; |
383 | break; |
384 | case LM95241_CHIP_ID: |
385 | name = "lm95241" ; |
386 | break; |
387 | default: |
388 | return -ENODEV; |
389 | } |
390 | |
391 | /* Fill the i2c board info */ |
392 | strscpy(p: info->type, q: name, I2C_NAME_SIZE); |
393 | return 0; |
394 | } |
395 | |
396 | static void lm95241_init_client(struct i2c_client *client, |
397 | struct lm95241_data *data) |
398 | { |
399 | data->interval = 1000; |
400 | data->config = CFG_CR1000; |
401 | data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); |
402 | |
403 | i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, value: data->config); |
404 | i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, |
405 | R1FE_MASK | R2FE_MASK); |
406 | i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, |
407 | value: data->trutherm); |
408 | i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, |
409 | value: data->model); |
410 | } |
411 | |
412 | static const struct hwmon_channel_info * const lm95241_info[] = { |
413 | HWMON_CHANNEL_INFO(chip, |
414 | HWMON_C_UPDATE_INTERVAL), |
415 | HWMON_CHANNEL_INFO(temp, |
416 | HWMON_T_INPUT, |
417 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | |
418 | HWMON_T_TYPE | HWMON_T_FAULT, |
419 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | |
420 | HWMON_T_TYPE | HWMON_T_FAULT), |
421 | NULL |
422 | }; |
423 | |
424 | static const struct hwmon_ops lm95241_hwmon_ops = { |
425 | .is_visible = lm95241_is_visible, |
426 | .read = lm95241_read, |
427 | .write = lm95241_write, |
428 | }; |
429 | |
430 | static const struct hwmon_chip_info lm95241_chip_info = { |
431 | .ops = &lm95241_hwmon_ops, |
432 | .info = lm95241_info, |
433 | }; |
434 | |
435 | static int lm95241_probe(struct i2c_client *client) |
436 | { |
437 | struct device *dev = &client->dev; |
438 | struct lm95241_data *data; |
439 | struct device *hwmon_dev; |
440 | |
441 | data = devm_kzalloc(dev, size: sizeof(struct lm95241_data), GFP_KERNEL); |
442 | if (!data) |
443 | return -ENOMEM; |
444 | |
445 | data->client = client; |
446 | mutex_init(&data->update_lock); |
447 | |
448 | /* Initialize the LM95241 chip */ |
449 | lm95241_init_client(client, data); |
450 | |
451 | hwmon_dev = devm_hwmon_device_register_with_info(dev, name: client->name, |
452 | drvdata: data, |
453 | info: &lm95241_chip_info, |
454 | NULL); |
455 | return PTR_ERR_OR_ZERO(ptr: hwmon_dev); |
456 | } |
457 | |
458 | /* Driver data (common to all clients) */ |
459 | static const struct i2c_device_id lm95241_id[] = { |
460 | { "lm95231" , 0 }, |
461 | { "lm95241" , 0 }, |
462 | { } |
463 | }; |
464 | MODULE_DEVICE_TABLE(i2c, lm95241_id); |
465 | |
466 | static struct i2c_driver lm95241_driver = { |
467 | .class = I2C_CLASS_HWMON, |
468 | .driver = { |
469 | .name = DEVNAME, |
470 | }, |
471 | .probe = lm95241_probe, |
472 | .id_table = lm95241_id, |
473 | .detect = lm95241_detect, |
474 | .address_list = normal_i2c, |
475 | }; |
476 | |
477 | module_i2c_driver(lm95241_driver); |
478 | |
479 | MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>" ); |
480 | MODULE_DESCRIPTION("LM95231/LM95241 sensor driver" ); |
481 | MODULE_LICENSE("GPL" ); |
482 | |