treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
[sfrench/cifs-2.6.git] / drivers / hwmon / lm95241.c
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         char valid;             /* zero 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                                                      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 = 1;
122         }
123
124         mutex_unlock(&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(data->temp[channel * 2],
152                                                 data->temp[channel * 2 + 1]);
153                 else
154                         *val = temp_from_reg_unsigned(data->temp[channel * 2],
155                                                 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(data->client,
228                                                 LM95241_REG_RW_CONFIG, config);
229                 break;
230         default:
231                 ret = -EOPNOTSUPP;
232                 break;
233         }
234         mutex_unlock(&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 = 0;
261                 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,
262                                                 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 = 0;
277                 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,
278                                                 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                                                 data->model);
307                 if (ret < 0)
308                         break;
309                 ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM,
310                                                 data->trutherm);
311                 break;
312         default:
313                 ret = -EOPNOTSUPP;
314                 break;
315         }
316
317         mutex_unlock(&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(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
373                 return -ENODEV;
374
375         mfg_id = i2c_smbus_read_byte_data(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(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         strlcpy(info->type, 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, 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                                   data->trutherm);
408         i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL,
409                                   data->model);
410 }
411
412 static const struct hwmon_channel_info *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                          const struct i2c_device_id *id)
437 {
438         struct device *dev = &client->dev;
439         struct lm95241_data *data;
440         struct device *hwmon_dev;
441
442         data = devm_kzalloc(dev, sizeof(struct lm95241_data), GFP_KERNEL);
443         if (!data)
444                 return -ENOMEM;
445
446         data->client = client;
447         mutex_init(&data->update_lock);
448
449         /* Initialize the LM95241 chip */
450         lm95241_init_client(client, data);
451
452         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
453                                                            data,
454                                                            &lm95241_chip_info,
455                                                            NULL);
456         return PTR_ERR_OR_ZERO(hwmon_dev);
457 }
458
459 /* Driver data (common to all clients) */
460 static const struct i2c_device_id lm95241_id[] = {
461         { "lm95231", 0 },
462         { "lm95241", 0 },
463         { }
464 };
465 MODULE_DEVICE_TABLE(i2c, lm95241_id);
466
467 static struct i2c_driver lm95241_driver = {
468         .class          = I2C_CLASS_HWMON,
469         .driver = {
470                 .name   = DEVNAME,
471         },
472         .probe          = lm95241_probe,
473         .id_table       = lm95241_id,
474         .detect         = lm95241_detect,
475         .address_list   = normal_i2c,
476 };
477
478 module_i2c_driver(lm95241_driver);
479
480 MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>");
481 MODULE_DESCRIPTION("LM95231/LM95241 sensor driver");
482 MODULE_LICENSE("GPL");