1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * lm83.c - Part of lm_sensors, Linux kernel modules for hardware |
4 | * monitoring |
5 | * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de> |
6 | * |
7 | * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is |
8 | * a sensor chip made by National Semiconductor. It reports up to four |
9 | * temperatures (its own plus up to three external ones) with a 1 deg |
10 | * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained |
11 | * from National's website at: |
12 | * http://www.national.com/pf/LM/LM83.html |
13 | * Since the datasheet omits to give the chip stepping code, I give it |
14 | * here: 0x03 (at register 0xff). |
15 | * |
16 | * Also supports the LM82 temp sensor, which is basically a stripped down |
17 | * model of the LM83. Datasheet is here: |
18 | * http://www.national.com/pf/LM/LM82.html |
19 | */ |
20 | |
21 | #include <linux/bits.h> |
22 | #include <linux/err.h> |
23 | #include <linux/i2c.h> |
24 | #include <linux/init.h> |
25 | #include <linux/hwmon.h> |
26 | #include <linux/module.h> |
27 | #include <linux/regmap.h> |
28 | #include <linux/slab.h> |
29 | |
30 | /* |
31 | * Addresses to scan |
32 | * Address is selected using 2 three-level pins, resulting in 9 possible |
33 | * addresses. |
34 | */ |
35 | |
36 | static const unsigned short normal_i2c[] = { |
37 | 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; |
38 | |
39 | enum chips { lm83, lm82 }; |
40 | |
41 | /* |
42 | * The LM83 registers |
43 | * Manufacturer ID is 0x01 for National Semiconductor. |
44 | */ |
45 | |
46 | #define LM83_REG_R_MAN_ID 0xFE |
47 | #define LM83_REG_R_CHIP_ID 0xFF |
48 | #define LM83_REG_R_CONFIG 0x03 |
49 | #define LM83_REG_W_CONFIG 0x09 |
50 | #define LM83_REG_R_STATUS1 0x02 |
51 | #define LM83_REG_R_STATUS2 0x35 |
52 | #define LM83_REG_R_LOCAL_TEMP 0x00 |
53 | #define LM83_REG_R_LOCAL_HIGH 0x05 |
54 | #define LM83_REG_W_LOCAL_HIGH 0x0B |
55 | #define LM83_REG_R_REMOTE1_TEMP 0x30 |
56 | #define LM83_REG_R_REMOTE1_HIGH 0x38 |
57 | #define LM83_REG_W_REMOTE1_HIGH 0x50 |
58 | #define LM83_REG_R_REMOTE2_TEMP 0x01 |
59 | #define LM83_REG_R_REMOTE2_HIGH 0x07 |
60 | #define LM83_REG_W_REMOTE2_HIGH 0x0D |
61 | #define LM83_REG_R_REMOTE3_TEMP 0x31 |
62 | #define LM83_REG_R_REMOTE3_HIGH 0x3A |
63 | #define LM83_REG_W_REMOTE3_HIGH 0x52 |
64 | #define LM83_REG_R_TCRIT 0x42 |
65 | #define LM83_REG_W_TCRIT 0x5A |
66 | |
67 | static const u8 LM83_REG_TEMP[] = { |
68 | LM83_REG_R_LOCAL_TEMP, |
69 | LM83_REG_R_REMOTE1_TEMP, |
70 | LM83_REG_R_REMOTE2_TEMP, |
71 | LM83_REG_R_REMOTE3_TEMP, |
72 | }; |
73 | |
74 | static const u8 LM83_REG_MAX[] = { |
75 | LM83_REG_R_LOCAL_HIGH, |
76 | LM83_REG_R_REMOTE1_HIGH, |
77 | LM83_REG_R_REMOTE2_HIGH, |
78 | LM83_REG_R_REMOTE3_HIGH, |
79 | }; |
80 | |
81 | /* alarm and fault registers and bits, indexed by channel */ |
82 | static const u8 LM83_ALARM_REG[] = { |
83 | LM83_REG_R_STATUS1, LM83_REG_R_STATUS2, LM83_REG_R_STATUS1, LM83_REG_R_STATUS2 |
84 | }; |
85 | |
86 | static const u8 LM83_MAX_ALARM_BIT[] = { |
87 | BIT(6), BIT(7), BIT(4), BIT(4) |
88 | }; |
89 | |
90 | static const u8 LM83_CRIT_ALARM_BIT[] = { |
91 | BIT(0), BIT(0), BIT(1), BIT(1) |
92 | }; |
93 | |
94 | static const u8 LM83_FAULT_BIT[] = { |
95 | 0, BIT(5), BIT(2), BIT(2) |
96 | }; |
97 | |
98 | /* |
99 | * Client data (each client gets its own) |
100 | */ |
101 | |
102 | struct lm83_data { |
103 | struct regmap *regmap; |
104 | enum chips type; |
105 | }; |
106 | |
107 | /* regmap code */ |
108 | |
109 | static int lm83_regmap_reg_read(void *context, unsigned int reg, unsigned int *val) |
110 | { |
111 | struct i2c_client *client = context; |
112 | int ret; |
113 | |
114 | ret = i2c_smbus_read_byte_data(client, command: reg); |
115 | if (ret < 0) |
116 | return ret; |
117 | |
118 | *val = ret; |
119 | return 0; |
120 | } |
121 | |
122 | /* |
123 | * The regmap write function maps read register addresses to write register |
124 | * addresses. This is necessary for regmap register caching to work. |
125 | * An alternative would be to clear the regmap cache whenever a register is |
126 | * written, but that would be much more expensive. |
127 | */ |
128 | static int lm83_regmap_reg_write(void *context, unsigned int reg, unsigned int val) |
129 | { |
130 | struct i2c_client *client = context; |
131 | |
132 | switch (reg) { |
133 | case LM83_REG_R_CONFIG: |
134 | case LM83_REG_R_LOCAL_HIGH: |
135 | case LM83_REG_R_REMOTE2_HIGH: |
136 | reg += 0x06; |
137 | break; |
138 | case LM83_REG_R_REMOTE1_HIGH: |
139 | case LM83_REG_R_REMOTE3_HIGH: |
140 | case LM83_REG_R_TCRIT: |
141 | reg += 0x18; |
142 | break; |
143 | default: |
144 | break; |
145 | } |
146 | |
147 | return i2c_smbus_write_byte_data(client, command: reg, value: val); |
148 | } |
149 | |
150 | static bool lm83_regmap_is_volatile(struct device *dev, unsigned int reg) |
151 | { |
152 | switch (reg) { |
153 | case LM83_REG_R_LOCAL_TEMP: |
154 | case LM83_REG_R_REMOTE1_TEMP: |
155 | case LM83_REG_R_REMOTE2_TEMP: |
156 | case LM83_REG_R_REMOTE3_TEMP: |
157 | case LM83_REG_R_STATUS1: |
158 | case LM83_REG_R_STATUS2: |
159 | return true; |
160 | default: |
161 | return false; |
162 | } |
163 | } |
164 | |
165 | static const struct regmap_config lm83_regmap_config = { |
166 | .reg_bits = 8, |
167 | .val_bits = 8, |
168 | .cache_type = REGCACHE_MAPLE, |
169 | .volatile_reg = lm83_regmap_is_volatile, |
170 | .reg_read = lm83_regmap_reg_read, |
171 | .reg_write = lm83_regmap_reg_write, |
172 | }; |
173 | |
174 | /* hwmon API */ |
175 | |
176 | static int lm83_temp_read(struct device *dev, u32 attr, int channel, long *val) |
177 | { |
178 | struct lm83_data *data = dev_get_drvdata(dev); |
179 | unsigned int regval; |
180 | int err; |
181 | |
182 | switch (attr) { |
183 | case hwmon_temp_input: |
184 | err = regmap_read(map: data->regmap, reg: LM83_REG_TEMP[channel], val: ®val); |
185 | if (err < 0) |
186 | return err; |
187 | *val = (s8)regval * 1000; |
188 | break; |
189 | case hwmon_temp_max: |
190 | err = regmap_read(map: data->regmap, reg: LM83_REG_MAX[channel], val: ®val); |
191 | if (err < 0) |
192 | return err; |
193 | *val = (s8)regval * 1000; |
194 | break; |
195 | case hwmon_temp_crit: |
196 | err = regmap_read(map: data->regmap, LM83_REG_R_TCRIT, val: ®val); |
197 | if (err < 0) |
198 | return err; |
199 | *val = (s8)regval * 1000; |
200 | break; |
201 | case hwmon_temp_max_alarm: |
202 | err = regmap_read(map: data->regmap, reg: LM83_ALARM_REG[channel], val: ®val); |
203 | if (err < 0) |
204 | return err; |
205 | *val = !!(regval & LM83_MAX_ALARM_BIT[channel]); |
206 | break; |
207 | case hwmon_temp_crit_alarm: |
208 | err = regmap_read(map: data->regmap, reg: LM83_ALARM_REG[channel], val: ®val); |
209 | if (err < 0) |
210 | return err; |
211 | *val = !!(regval & LM83_CRIT_ALARM_BIT[channel]); |
212 | break; |
213 | case hwmon_temp_fault: |
214 | err = regmap_read(map: data->regmap, reg: LM83_ALARM_REG[channel], val: ®val); |
215 | if (err < 0) |
216 | return err; |
217 | *val = !!(regval & LM83_FAULT_BIT[channel]); |
218 | break; |
219 | default: |
220 | return -EOPNOTSUPP; |
221 | } |
222 | return 0; |
223 | } |
224 | |
225 | static int lm83_temp_write(struct device *dev, u32 attr, int channel, long val) |
226 | { |
227 | struct lm83_data *data = dev_get_drvdata(dev); |
228 | unsigned int regval; |
229 | int err; |
230 | |
231 | regval = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000); |
232 | |
233 | switch (attr) { |
234 | case hwmon_temp_max: |
235 | err = regmap_write(map: data->regmap, reg: LM83_REG_MAX[channel], val: regval); |
236 | if (err < 0) |
237 | return err; |
238 | break; |
239 | case hwmon_temp_crit: |
240 | err = regmap_write(map: data->regmap, LM83_REG_R_TCRIT, val: regval); |
241 | if (err < 0) |
242 | return err; |
243 | break; |
244 | default: |
245 | return -EOPNOTSUPP; |
246 | } |
247 | return 0; |
248 | } |
249 | |
250 | static int lm83_chip_read(struct device *dev, u32 attr, int channel, long *val) |
251 | { |
252 | struct lm83_data *data = dev_get_drvdata(dev); |
253 | unsigned int regval; |
254 | int err; |
255 | |
256 | switch (attr) { |
257 | case hwmon_chip_alarms: |
258 | err = regmap_read(map: data->regmap, LM83_REG_R_STATUS1, val: ®val); |
259 | if (err < 0) |
260 | return err; |
261 | *val = regval; |
262 | err = regmap_read(map: data->regmap, LM83_REG_R_STATUS2, val: ®val); |
263 | if (err < 0) |
264 | return err; |
265 | *val |= regval << 8; |
266 | return 0; |
267 | default: |
268 | return -EOPNOTSUPP; |
269 | } |
270 | |
271 | return 0; |
272 | } |
273 | |
274 | static int lm83_read(struct device *dev, enum hwmon_sensor_types type, |
275 | u32 attr, int channel, long *val) |
276 | { |
277 | switch (type) { |
278 | case hwmon_chip: |
279 | return lm83_chip_read(dev, attr, channel, val); |
280 | case hwmon_temp: |
281 | return lm83_temp_read(dev, attr, channel, val); |
282 | default: |
283 | return -EOPNOTSUPP; |
284 | } |
285 | } |
286 | |
287 | static int lm83_write(struct device *dev, enum hwmon_sensor_types type, |
288 | u32 attr, int channel, long val) |
289 | { |
290 | switch (type) { |
291 | case hwmon_temp: |
292 | return lm83_temp_write(dev, attr, channel, val); |
293 | default: |
294 | return -EOPNOTSUPP; |
295 | } |
296 | } |
297 | |
298 | static umode_t lm83_is_visible(const void *_data, enum hwmon_sensor_types type, |
299 | u32 attr, int channel) |
300 | { |
301 | const struct lm83_data *data = _data; |
302 | |
303 | /* |
304 | * LM82 only supports a single external channel, modeled as channel 2. |
305 | */ |
306 | if (data->type == lm82 && (channel == 1 || channel == 3)) |
307 | return 0; |
308 | |
309 | switch (type) { |
310 | case hwmon_chip: |
311 | if (attr == hwmon_chip_alarms) |
312 | return 0444; |
313 | break; |
314 | case hwmon_temp: |
315 | switch (attr) { |
316 | case hwmon_temp_input: |
317 | case hwmon_temp_max_alarm: |
318 | case hwmon_temp_crit_alarm: |
319 | return 0444; |
320 | case hwmon_temp_fault: |
321 | if (channel) |
322 | return 0444; |
323 | break; |
324 | case hwmon_temp_max: |
325 | return 0644; |
326 | case hwmon_temp_crit: |
327 | if (channel == 2) |
328 | return 0644; |
329 | return 0444; |
330 | default: |
331 | break; |
332 | } |
333 | break; |
334 | default: |
335 | break; |
336 | } |
337 | return 0; |
338 | } |
339 | |
340 | static const struct hwmon_channel_info * const lm83_info[] = { |
341 | HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS), |
342 | HWMON_CHANNEL_INFO(temp, |
343 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | |
344 | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM, |
345 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | |
346 | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_FAULT, |
347 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | |
348 | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_FAULT, |
349 | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | |
350 | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_FAULT |
351 | ), |
352 | NULL |
353 | }; |
354 | |
355 | static const struct hwmon_ops lm83_hwmon_ops = { |
356 | .is_visible = lm83_is_visible, |
357 | .read = lm83_read, |
358 | .write = lm83_write, |
359 | }; |
360 | |
361 | static const struct hwmon_chip_info lm83_chip_info = { |
362 | .ops = &lm83_hwmon_ops, |
363 | .info = lm83_info, |
364 | }; |
365 | |
366 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
367 | static int lm83_detect(struct i2c_client *client, |
368 | struct i2c_board_info *info) |
369 | { |
370 | struct i2c_adapter *adapter = client->adapter; |
371 | const char *name; |
372 | u8 man_id, chip_id; |
373 | |
374 | if (!i2c_check_functionality(adap: adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
375 | return -ENODEV; |
376 | |
377 | /* Detection */ |
378 | if ((i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) & 0xA8) || |
379 | (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) & 0x48) || |
380 | (i2c_smbus_read_byte_data(client, LM83_REG_R_CONFIG) & 0x41)) { |
381 | dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n" , |
382 | client->addr); |
383 | return -ENODEV; |
384 | } |
385 | |
386 | /* Identification */ |
387 | man_id = i2c_smbus_read_byte_data(client, LM83_REG_R_MAN_ID); |
388 | if (man_id != 0x01) /* National Semiconductor */ |
389 | return -ENODEV; |
390 | |
391 | chip_id = i2c_smbus_read_byte_data(client, LM83_REG_R_CHIP_ID); |
392 | switch (chip_id) { |
393 | case 0x03: |
394 | /* |
395 | * According to the LM82 datasheet dated March 2013, recent |
396 | * revisions of LM82 have a die revision of 0x03. This was |
397 | * confirmed with a real chip. Further details in this revision |
398 | * of the LM82 datasheet strongly suggest that LM82 is just a |
399 | * repackaged LM83. It is therefore impossible to distinguish |
400 | * those chips from LM83, and they will be misdetected as LM83. |
401 | */ |
402 | name = "lm83" ; |
403 | break; |
404 | case 0x01: |
405 | name = "lm82" ; |
406 | break; |
407 | default: |
408 | /* identification failed */ |
409 | dev_dbg(&adapter->dev, |
410 | "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n" , |
411 | man_id, chip_id); |
412 | return -ENODEV; |
413 | } |
414 | |
415 | strscpy(info->type, name, I2C_NAME_SIZE); |
416 | |
417 | return 0; |
418 | } |
419 | |
420 | static const struct i2c_device_id lm83_id[] = { |
421 | { "lm83" , lm83 }, |
422 | { "lm82" , lm82 }, |
423 | { } |
424 | }; |
425 | MODULE_DEVICE_TABLE(i2c, lm83_id); |
426 | |
427 | static int lm83_probe(struct i2c_client *client) |
428 | { |
429 | struct device *dev = &client->dev; |
430 | struct device *hwmon_dev; |
431 | struct lm83_data *data; |
432 | |
433 | data = devm_kzalloc(dev, size: sizeof(struct lm83_data), GFP_KERNEL); |
434 | if (!data) |
435 | return -ENOMEM; |
436 | |
437 | data->regmap = devm_regmap_init(dev, NULL, client, &lm83_regmap_config); |
438 | if (IS_ERR(ptr: data->regmap)) |
439 | return PTR_ERR(ptr: data->regmap); |
440 | |
441 | data->type = i2c_match_id(id: lm83_id, client)->driver_data; |
442 | |
443 | hwmon_dev = devm_hwmon_device_register_with_info(dev, name: client->name, |
444 | drvdata: data, info: &lm83_chip_info, NULL); |
445 | return PTR_ERR_OR_ZERO(ptr: hwmon_dev); |
446 | } |
447 | |
448 | /* |
449 | * Driver data (common to all clients) |
450 | */ |
451 | |
452 | static struct i2c_driver lm83_driver = { |
453 | .class = I2C_CLASS_HWMON, |
454 | .driver = { |
455 | .name = "lm83" , |
456 | }, |
457 | .probe = lm83_probe, |
458 | .id_table = lm83_id, |
459 | .detect = lm83_detect, |
460 | .address_list = normal_i2c, |
461 | }; |
462 | |
463 | module_i2c_driver(lm83_driver); |
464 | |
465 | MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>" ); |
466 | MODULE_DESCRIPTION("LM83 driver" ); |
467 | MODULE_LICENSE("GPL" ); |
468 | |