1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Industrial I/O driver for Microchip digital potentiometers
4 * Copyright (c) 2015 Axentia Technologies AB
5 * Author: Peter Rosin <peda@axentia.se>
6 *
7 * Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22096b.pdf
8 *
9 * DEVID #Wipers #Positions Resistor Opts (kOhm) i2c address
10 * mcp4531 1 129 5, 10, 50, 100 010111x
11 * mcp4532 1 129 5, 10, 50, 100 01011xx
12 * mcp4541 1 129 5, 10, 50, 100 010111x
13 * mcp4542 1 129 5, 10, 50, 100 01011xx
14 * mcp4551 1 257 5, 10, 50, 100 010111x
15 * mcp4552 1 257 5, 10, 50, 100 01011xx
16 * mcp4561 1 257 5, 10, 50, 100 010111x
17 * mcp4562 1 257 5, 10, 50, 100 01011xx
18 * mcp4631 2 129 5, 10, 50, 100 0101xxx
19 * mcp4632 2 129 5, 10, 50, 100 01011xx
20 * mcp4641 2 129 5, 10, 50, 100 0101xxx
21 * mcp4642 2 129 5, 10, 50, 100 01011xx
22 * mcp4651 2 257 5, 10, 50, 100 0101xxx
23 * mcp4652 2 257 5, 10, 50, 100 01011xx
24 * mcp4661 2 257 5, 10, 50, 100 0101xxx
25 * mcp4662 2 257 5, 10, 50, 100 01011xx
26 */
27
28 #include <linux/module.h>
29 #include <linux/i2c.h>
30 #include <linux/err.h>
31 #include <linux/property.h>
32
33 #include <linux/iio/iio.h>
34
35 struct mcp4531_cfg {
36 int wipers;
37 int avail[3];
38 int kohms;
39 };
40
41 enum mcp4531_type {
42 MCP453x_502,
43 MCP453x_103,
44 MCP453x_503,
45 MCP453x_104,
46 MCP454x_502,
47 MCP454x_103,
48 MCP454x_503,
49 MCP454x_104,
50 MCP455x_502,
51 MCP455x_103,
52 MCP455x_503,
53 MCP455x_104,
54 MCP456x_502,
55 MCP456x_103,
56 MCP456x_503,
57 MCP456x_104,
58 MCP463x_502,
59 MCP463x_103,
60 MCP463x_503,
61 MCP463x_104,
62 MCP464x_502,
63 MCP464x_103,
64 MCP464x_503,
65 MCP464x_104,
66 MCP465x_502,
67 MCP465x_103,
68 MCP465x_503,
69 MCP465x_104,
70 MCP466x_502,
71 MCP466x_103,
72 MCP466x_503,
73 MCP466x_104,
74 };
75
76 static const struct mcp4531_cfg mcp4531_cfg[] = {
77 [MCP453x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 5, },
78 [MCP453x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 10, },
79 [MCP453x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 50, },
80 [MCP453x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
81 [MCP454x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 5, },
82 [MCP454x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 10, },
83 [MCP454x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 50, },
84 [MCP454x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
85 [MCP455x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 5, },
86 [MCP455x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 10, },
87 [MCP455x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 50, },
88 [MCP455x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
89 [MCP456x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 5, },
90 [MCP456x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 10, },
91 [MCP456x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 50, },
92 [MCP456x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
93 [MCP463x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 5, },
94 [MCP463x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 10, },
95 [MCP463x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 50, },
96 [MCP463x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
97 [MCP464x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 5, },
98 [MCP464x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 10, },
99 [MCP464x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 50, },
100 [MCP464x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
101 [MCP465x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 5, },
102 [MCP465x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 10, },
103 [MCP465x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 50, },
104 [MCP465x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
105 [MCP466x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 5, },
106 [MCP466x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 10, },
107 [MCP466x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 50, },
108 [MCP466x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
109 };
110
111 #define MCP4531_WRITE (0 << 2)
112 #define MCP4531_INCR (1 << 2)
113 #define MCP4531_DECR (2 << 2)
114 #define MCP4531_READ (3 << 2)
115
116 #define MCP4531_WIPER_SHIFT (4)
117
118 struct mcp4531_data {
119 struct i2c_client *client;
120 const struct mcp4531_cfg *cfg;
121 };
122
123 #define MCP4531_CHANNEL(ch) { \
124 .type = IIO_RESISTANCE, \
125 .indexed = 1, \
126 .output = 1, \
127 .channel = (ch), \
128 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
129 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
130 .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW), \
131 }
132
133 static const struct iio_chan_spec mcp4531_channels[] = {
134 MCP4531_CHANNEL(0),
135 MCP4531_CHANNEL(1),
136 };
137
mcp4531_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)138 static int mcp4531_read_raw(struct iio_dev *indio_dev,
139 struct iio_chan_spec const *chan,
140 int *val, int *val2, long mask)
141 {
142 struct mcp4531_data *data = iio_priv(indio_dev);
143 int address = chan->channel << MCP4531_WIPER_SHIFT;
144 s32 ret;
145
146 switch (mask) {
147 case IIO_CHAN_INFO_RAW:
148 ret = i2c_smbus_read_word_swapped(data->client,
149 MCP4531_READ | address);
150 if (ret < 0)
151 return ret;
152 *val = ret;
153 return IIO_VAL_INT;
154 case IIO_CHAN_INFO_SCALE:
155 *val = 1000 * data->cfg->kohms;
156 *val2 = data->cfg->avail[2];
157 return IIO_VAL_FRACTIONAL;
158 }
159
160 return -EINVAL;
161 }
162
mcp4531_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)163 static int mcp4531_read_avail(struct iio_dev *indio_dev,
164 struct iio_chan_spec const *chan,
165 const int **vals, int *type, int *length,
166 long mask)
167 {
168 struct mcp4531_data *data = iio_priv(indio_dev);
169
170 switch (mask) {
171 case IIO_CHAN_INFO_RAW:
172 *length = ARRAY_SIZE(data->cfg->avail);
173 *vals = data->cfg->avail;
174 *type = IIO_VAL_INT;
175 return IIO_AVAIL_RANGE;
176 }
177
178 return -EINVAL;
179 }
180
mcp4531_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)181 static int mcp4531_write_raw(struct iio_dev *indio_dev,
182 struct iio_chan_spec const *chan,
183 int val, int val2, long mask)
184 {
185 struct mcp4531_data *data = iio_priv(indio_dev);
186 int address = chan->channel << MCP4531_WIPER_SHIFT;
187
188 switch (mask) {
189 case IIO_CHAN_INFO_RAW:
190 if (val > data->cfg->avail[2] || val < 0)
191 return -EINVAL;
192 break;
193 default:
194 return -EINVAL;
195 }
196
197 return i2c_smbus_write_byte_data(data->client,
198 MCP4531_WRITE | address | (val >> 8),
199 val & 0xff);
200 }
201
202 static const struct iio_info mcp4531_info = {
203 .read_raw = mcp4531_read_raw,
204 .read_avail = mcp4531_read_avail,
205 .write_raw = mcp4531_write_raw,
206 };
207
208 #define MCP4531_ID_TABLE(_name, cfg) { \
209 .name = _name, \
210 .driver_data = (kernel_ulong_t)&mcp4531_cfg[cfg], \
211 }
212
213 static const struct i2c_device_id mcp4531_id[] = {
214 MCP4531_ID_TABLE("mcp4531-502", MCP453x_502),
215 MCP4531_ID_TABLE("mcp4531-103", MCP453x_103),
216 MCP4531_ID_TABLE("mcp4531-503", MCP453x_503),
217 MCP4531_ID_TABLE("mcp4531-104", MCP453x_104),
218 MCP4531_ID_TABLE("mcp4532-502", MCP453x_502),
219 MCP4531_ID_TABLE("mcp4532-103", MCP453x_103),
220 MCP4531_ID_TABLE("mcp4532-503", MCP453x_503),
221 MCP4531_ID_TABLE("mcp4532-104", MCP453x_104),
222 MCP4531_ID_TABLE("mcp4541-502", MCP454x_502),
223 MCP4531_ID_TABLE("mcp4541-103", MCP454x_103),
224 MCP4531_ID_TABLE("mcp4541-503", MCP454x_503),
225 MCP4531_ID_TABLE("mcp4541-104", MCP454x_104),
226 MCP4531_ID_TABLE("mcp4542-502", MCP454x_502),
227 MCP4531_ID_TABLE("mcp4542-103", MCP454x_103),
228 MCP4531_ID_TABLE("mcp4542-503", MCP454x_503),
229 MCP4531_ID_TABLE("mcp4542-104", MCP454x_104),
230 MCP4531_ID_TABLE("mcp4551-502", MCP455x_502),
231 MCP4531_ID_TABLE("mcp4551-103", MCP455x_103),
232 MCP4531_ID_TABLE("mcp4551-503", MCP455x_503),
233 MCP4531_ID_TABLE("mcp4551-104", MCP455x_104),
234 MCP4531_ID_TABLE("mcp4552-502", MCP455x_502),
235 MCP4531_ID_TABLE("mcp4552-103", MCP455x_103),
236 MCP4531_ID_TABLE("mcp4552-503", MCP455x_503),
237 MCP4531_ID_TABLE("mcp4552-104", MCP455x_104),
238 MCP4531_ID_TABLE("mcp4561-502", MCP456x_502),
239 MCP4531_ID_TABLE("mcp4561-103", MCP456x_103),
240 MCP4531_ID_TABLE("mcp4561-503", MCP456x_503),
241 MCP4531_ID_TABLE("mcp4561-104", MCP456x_104),
242 MCP4531_ID_TABLE("mcp4562-502", MCP456x_502),
243 MCP4531_ID_TABLE("mcp4562-103", MCP456x_103),
244 MCP4531_ID_TABLE("mcp4562-503", MCP456x_503),
245 MCP4531_ID_TABLE("mcp4562-104", MCP456x_104),
246 MCP4531_ID_TABLE("mcp4631-502", MCP463x_502),
247 MCP4531_ID_TABLE("mcp4631-103", MCP463x_103),
248 MCP4531_ID_TABLE("mcp4631-503", MCP463x_503),
249 MCP4531_ID_TABLE("mcp4631-104", MCP463x_104),
250 MCP4531_ID_TABLE("mcp4632-502", MCP463x_502),
251 MCP4531_ID_TABLE("mcp4632-103", MCP463x_103),
252 MCP4531_ID_TABLE("mcp4632-503", MCP463x_503),
253 MCP4531_ID_TABLE("mcp4632-104", MCP463x_104),
254 MCP4531_ID_TABLE("mcp4641-502", MCP464x_502),
255 MCP4531_ID_TABLE("mcp4641-103", MCP464x_103),
256 MCP4531_ID_TABLE("mcp4641-503", MCP464x_503),
257 MCP4531_ID_TABLE("mcp4641-104", MCP464x_104),
258 MCP4531_ID_TABLE("mcp4642-502", MCP464x_502),
259 MCP4531_ID_TABLE("mcp4642-103", MCP464x_103),
260 MCP4531_ID_TABLE("mcp4642-503", MCP464x_503),
261 MCP4531_ID_TABLE("mcp4642-104", MCP464x_104),
262 MCP4531_ID_TABLE("mcp4651-502", MCP465x_502),
263 MCP4531_ID_TABLE("mcp4651-103", MCP465x_103),
264 MCP4531_ID_TABLE("mcp4651-503", MCP465x_503),
265 MCP4531_ID_TABLE("mcp4651-104", MCP465x_104),
266 MCP4531_ID_TABLE("mcp4652-502", MCP465x_502),
267 MCP4531_ID_TABLE("mcp4652-103", MCP465x_103),
268 MCP4531_ID_TABLE("mcp4652-503", MCP465x_503),
269 MCP4531_ID_TABLE("mcp4652-104", MCP465x_104),
270 MCP4531_ID_TABLE("mcp4661-502", MCP466x_502),
271 MCP4531_ID_TABLE("mcp4661-103", MCP466x_103),
272 MCP4531_ID_TABLE("mcp4661-503", MCP466x_503),
273 MCP4531_ID_TABLE("mcp4661-104", MCP466x_104),
274 MCP4531_ID_TABLE("mcp4662-502", MCP466x_502),
275 MCP4531_ID_TABLE("mcp4662-103", MCP466x_103),
276 MCP4531_ID_TABLE("mcp4662-503", MCP466x_503),
277 MCP4531_ID_TABLE("mcp4662-104", MCP466x_104),
278 { }
279 };
280 MODULE_DEVICE_TABLE(i2c, mcp4531_id);
281
282 #define MCP4531_COMPATIBLE(of_compatible, cfg) { \
283 .compatible = of_compatible, \
284 .data = &mcp4531_cfg[cfg], \
285 }
286
287 static const struct of_device_id mcp4531_of_match[] = {
288 MCP4531_COMPATIBLE("microchip,mcp4531-502", MCP453x_502),
289 MCP4531_COMPATIBLE("microchip,mcp4531-103", MCP453x_103),
290 MCP4531_COMPATIBLE("microchip,mcp4531-503", MCP453x_503),
291 MCP4531_COMPATIBLE("microchip,mcp4531-104", MCP453x_104),
292 MCP4531_COMPATIBLE("microchip,mcp4532-502", MCP453x_502),
293 MCP4531_COMPATIBLE("microchip,mcp4532-103", MCP453x_103),
294 MCP4531_COMPATIBLE("microchip,mcp4532-503", MCP453x_503),
295 MCP4531_COMPATIBLE("microchip,mcp4532-104", MCP453x_104),
296 MCP4531_COMPATIBLE("microchip,mcp4541-502", MCP454x_502),
297 MCP4531_COMPATIBLE("microchip,mcp4541-103", MCP454x_103),
298 MCP4531_COMPATIBLE("microchip,mcp4541-503", MCP454x_503),
299 MCP4531_COMPATIBLE("microchip,mcp4541-104", MCP454x_104),
300 MCP4531_COMPATIBLE("microchip,mcp4542-502", MCP454x_502),
301 MCP4531_COMPATIBLE("microchip,mcp4542-103", MCP454x_103),
302 MCP4531_COMPATIBLE("microchip,mcp4542-503", MCP454x_503),
303 MCP4531_COMPATIBLE("microchip,mcp4542-104", MCP454x_104),
304 MCP4531_COMPATIBLE("microchip,mcp4551-502", MCP455x_502),
305 MCP4531_COMPATIBLE("microchip,mcp4551-103", MCP455x_103),
306 MCP4531_COMPATIBLE("microchip,mcp4551-503", MCP455x_503),
307 MCP4531_COMPATIBLE("microchip,mcp4551-104", MCP455x_104),
308 MCP4531_COMPATIBLE("microchip,mcp4552-502", MCP455x_502),
309 MCP4531_COMPATIBLE("microchip,mcp4552-103", MCP455x_103),
310 MCP4531_COMPATIBLE("microchip,mcp4552-503", MCP455x_503),
311 MCP4531_COMPATIBLE("microchip,mcp4552-104", MCP455x_104),
312 MCP4531_COMPATIBLE("microchip,mcp4561-502", MCP456x_502),
313 MCP4531_COMPATIBLE("microchip,mcp4561-103", MCP456x_103),
314 MCP4531_COMPATIBLE("microchip,mcp4561-503", MCP456x_503),
315 MCP4531_COMPATIBLE("microchip,mcp4561-104", MCP456x_104),
316 MCP4531_COMPATIBLE("microchip,mcp4562-502", MCP456x_502),
317 MCP4531_COMPATIBLE("microchip,mcp4562-103", MCP456x_103),
318 MCP4531_COMPATIBLE("microchip,mcp4562-503", MCP456x_503),
319 MCP4531_COMPATIBLE("microchip,mcp4562-104", MCP456x_104),
320 MCP4531_COMPATIBLE("microchip,mcp4631-502", MCP463x_502),
321 MCP4531_COMPATIBLE("microchip,mcp4631-103", MCP463x_103),
322 MCP4531_COMPATIBLE("microchip,mcp4631-503", MCP463x_503),
323 MCP4531_COMPATIBLE("microchip,mcp4631-104", MCP463x_104),
324 MCP4531_COMPATIBLE("microchip,mcp4632-502", MCP463x_502),
325 MCP4531_COMPATIBLE("microchip,mcp4632-103", MCP463x_103),
326 MCP4531_COMPATIBLE("microchip,mcp4632-503", MCP463x_503),
327 MCP4531_COMPATIBLE("microchip,mcp4632-104", MCP463x_104),
328 MCP4531_COMPATIBLE("microchip,mcp4641-502", MCP464x_502),
329 MCP4531_COMPATIBLE("microchip,mcp4641-103", MCP464x_103),
330 MCP4531_COMPATIBLE("microchip,mcp4641-503", MCP464x_503),
331 MCP4531_COMPATIBLE("microchip,mcp4641-104", MCP464x_104),
332 MCP4531_COMPATIBLE("microchip,mcp4642-502", MCP464x_502),
333 MCP4531_COMPATIBLE("microchip,mcp4642-103", MCP464x_103),
334 MCP4531_COMPATIBLE("microchip,mcp4642-503", MCP464x_503),
335 MCP4531_COMPATIBLE("microchip,mcp4642-104", MCP464x_104),
336 MCP4531_COMPATIBLE("microchip,mcp4651-502", MCP465x_502),
337 MCP4531_COMPATIBLE("microchip,mcp4651-103", MCP465x_103),
338 MCP4531_COMPATIBLE("microchip,mcp4651-503", MCP465x_503),
339 MCP4531_COMPATIBLE("microchip,mcp4651-104", MCP465x_104),
340 MCP4531_COMPATIBLE("microchip,mcp4652-502", MCP465x_502),
341 MCP4531_COMPATIBLE("microchip,mcp4652-103", MCP465x_103),
342 MCP4531_COMPATIBLE("microchip,mcp4652-503", MCP465x_503),
343 MCP4531_COMPATIBLE("microchip,mcp4652-104", MCP465x_104),
344 MCP4531_COMPATIBLE("microchip,mcp4661-502", MCP466x_502),
345 MCP4531_COMPATIBLE("microchip,mcp4661-103", MCP466x_103),
346 MCP4531_COMPATIBLE("microchip,mcp4661-503", MCP466x_503),
347 MCP4531_COMPATIBLE("microchip,mcp4661-104", MCP466x_104),
348 MCP4531_COMPATIBLE("microchip,mcp4662-502", MCP466x_502),
349 MCP4531_COMPATIBLE("microchip,mcp4662-103", MCP466x_103),
350 MCP4531_COMPATIBLE("microchip,mcp4662-503", MCP466x_503),
351 MCP4531_COMPATIBLE("microchip,mcp4662-104", MCP466x_104),
352 { }
353 };
354 MODULE_DEVICE_TABLE(of, mcp4531_of_match);
355
mcp4531_probe(struct i2c_client * client)356 static int mcp4531_probe(struct i2c_client *client)
357 {
358 struct device *dev = &client->dev;
359 struct mcp4531_data *data;
360 struct iio_dev *indio_dev;
361
362 if (!i2c_check_functionality(client->adapter,
363 I2C_FUNC_SMBUS_WORD_DATA)) {
364 dev_err(dev, "SMBUS Word Data not supported\n");
365 return -EOPNOTSUPP;
366 }
367
368 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
369 if (!indio_dev)
370 return -ENOMEM;
371 data = iio_priv(indio_dev);
372 i2c_set_clientdata(client, indio_dev);
373 data->client = client;
374
375 data->cfg = i2c_get_match_data(client);
376
377 indio_dev->info = &mcp4531_info;
378 indio_dev->channels = mcp4531_channels;
379 indio_dev->num_channels = data->cfg->wipers;
380 indio_dev->name = client->name;
381
382 return devm_iio_device_register(dev, indio_dev);
383 }
384
385 static struct i2c_driver mcp4531_driver = {
386 .driver = {
387 .name = "mcp4531",
388 .of_match_table = mcp4531_of_match,
389 },
390 .probe = mcp4531_probe,
391 .id_table = mcp4531_id,
392 };
393
394 module_i2c_driver(mcp4531_driver);
395
396 MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
397 MODULE_DESCRIPTION("MCP4531 digital potentiometer");
398 MODULE_LICENSE("GPL v2");
399