mcp4531.c 14 KB

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  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. #include <linux/module.h>
  28. #include <linux/i2c.h>
  29. #include <linux/err.h>
  30. #include <linux/mod_devicetable.h>
  31. #include <linux/property.h>
  32. #include <linux/iio/iio.h>
  33. struct mcp4531_cfg {
  34. int wipers;
  35. int avail[3];
  36. int kohms;
  37. };
  38. enum mcp4531_type {
  39. MCP453x_502,
  40. MCP453x_103,
  41. MCP453x_503,
  42. MCP453x_104,
  43. MCP454x_502,
  44. MCP454x_103,
  45. MCP454x_503,
  46. MCP454x_104,
  47. MCP455x_502,
  48. MCP455x_103,
  49. MCP455x_503,
  50. MCP455x_104,
  51. MCP456x_502,
  52. MCP456x_103,
  53. MCP456x_503,
  54. MCP456x_104,
  55. MCP463x_502,
  56. MCP463x_103,
  57. MCP463x_503,
  58. MCP463x_104,
  59. MCP464x_502,
  60. MCP464x_103,
  61. MCP464x_503,
  62. MCP464x_104,
  63. MCP465x_502,
  64. MCP465x_103,
  65. MCP465x_503,
  66. MCP465x_104,
  67. MCP466x_502,
  68. MCP466x_103,
  69. MCP466x_503,
  70. MCP466x_104,
  71. };
  72. static const struct mcp4531_cfg mcp4531_cfg[] = {
  73. [MCP453x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 5, },
  74. [MCP453x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 10, },
  75. [MCP453x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 50, },
  76. [MCP453x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
  77. [MCP454x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 5, },
  78. [MCP454x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 10, },
  79. [MCP454x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 50, },
  80. [MCP454x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
  81. [MCP455x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 5, },
  82. [MCP455x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 10, },
  83. [MCP455x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 50, },
  84. [MCP455x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
  85. [MCP456x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 5, },
  86. [MCP456x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 10, },
  87. [MCP456x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 50, },
  88. [MCP456x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
  89. [MCP463x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 5, },
  90. [MCP463x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 10, },
  91. [MCP463x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 50, },
  92. [MCP463x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
  93. [MCP464x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 5, },
  94. [MCP464x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 10, },
  95. [MCP464x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 50, },
  96. [MCP464x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
  97. [MCP465x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 5, },
  98. [MCP465x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 10, },
  99. [MCP465x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 50, },
  100. [MCP465x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
  101. [MCP466x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 5, },
  102. [MCP466x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 10, },
  103. [MCP466x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 50, },
  104. [MCP466x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
  105. };
  106. #define MCP4531_WRITE (0 << 2)
  107. #define MCP4531_INCR (1 << 2)
  108. #define MCP4531_DECR (2 << 2)
  109. #define MCP4531_READ (3 << 2)
  110. #define MCP4531_WIPER_SHIFT (4)
  111. struct mcp4531_data {
  112. struct i2c_client *client;
  113. const struct mcp4531_cfg *cfg;
  114. };
  115. #define MCP4531_CHANNEL(ch) { \
  116. .type = IIO_RESISTANCE, \
  117. .indexed = 1, \
  118. .output = 1, \
  119. .channel = (ch), \
  120. .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
  121. .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
  122. .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW), \
  123. }
  124. static const struct iio_chan_spec mcp4531_channels[] = {
  125. MCP4531_CHANNEL(0),
  126. MCP4531_CHANNEL(1),
  127. };
  128. static int mcp4531_read_raw(struct iio_dev *indio_dev,
  129. struct iio_chan_spec const *chan,
  130. int *val, int *val2, long mask)
  131. {
  132. struct mcp4531_data *data = iio_priv(indio_dev);
  133. int address = chan->channel << MCP4531_WIPER_SHIFT;
  134. s32 ret;
  135. switch (mask) {
  136. case IIO_CHAN_INFO_RAW:
  137. ret = i2c_smbus_read_word_swapped(data->client,
  138. MCP4531_READ | address);
  139. if (ret < 0)
  140. return ret;
  141. *val = ret;
  142. return IIO_VAL_INT;
  143. case IIO_CHAN_INFO_SCALE:
  144. *val = 1000 * data->cfg->kohms;
  145. *val2 = data->cfg->avail[2];
  146. return IIO_VAL_FRACTIONAL;
  147. }
  148. return -EINVAL;
  149. }
  150. static int mcp4531_read_avail(struct iio_dev *indio_dev,
  151. struct iio_chan_spec const *chan,
  152. const int **vals, int *type, int *length,
  153. long mask)
  154. {
  155. struct mcp4531_data *data = iio_priv(indio_dev);
  156. switch (mask) {
  157. case IIO_CHAN_INFO_RAW:
  158. *length = ARRAY_SIZE(data->cfg->avail);
  159. *vals = data->cfg->avail;
  160. *type = IIO_VAL_INT;
  161. return IIO_AVAIL_RANGE;
  162. }
  163. return -EINVAL;
  164. }
  165. static int mcp4531_write_raw(struct iio_dev *indio_dev,
  166. struct iio_chan_spec const *chan,
  167. int val, int val2, long mask)
  168. {
  169. struct mcp4531_data *data = iio_priv(indio_dev);
  170. int address = chan->channel << MCP4531_WIPER_SHIFT;
  171. switch (mask) {
  172. case IIO_CHAN_INFO_RAW:
  173. if (val > data->cfg->avail[2] || val < 0)
  174. return -EINVAL;
  175. break;
  176. default:
  177. return -EINVAL;
  178. }
  179. return i2c_smbus_write_byte_data(data->client,
  180. MCP4531_WRITE | address | (val >> 8),
  181. val & 0xff);
  182. }
  183. static const struct iio_info mcp4531_info = {
  184. .read_raw = mcp4531_read_raw,
  185. .read_avail = mcp4531_read_avail,
  186. .write_raw = mcp4531_write_raw,
  187. };
  188. static const struct i2c_device_id mcp4531_id[] = {
  189. { "mcp4531-502", MCP453x_502 },
  190. { "mcp4531-103", MCP453x_103 },
  191. { "mcp4531-503", MCP453x_503 },
  192. { "mcp4531-104", MCP453x_104 },
  193. { "mcp4532-502", MCP453x_502 },
  194. { "mcp4532-103", MCP453x_103 },
  195. { "mcp4532-503", MCP453x_503 },
  196. { "mcp4532-104", MCP453x_104 },
  197. { "mcp4541-502", MCP454x_502 },
  198. { "mcp4541-103", MCP454x_103 },
  199. { "mcp4541-503", MCP454x_503 },
  200. { "mcp4541-104", MCP454x_104 },
  201. { "mcp4542-502", MCP454x_502 },
  202. { "mcp4542-103", MCP454x_103 },
  203. { "mcp4542-503", MCP454x_503 },
  204. { "mcp4542-104", MCP454x_104 },
  205. { "mcp4551-502", MCP455x_502 },
  206. { "mcp4551-103", MCP455x_103 },
  207. { "mcp4551-503", MCP455x_503 },
  208. { "mcp4551-104", MCP455x_104 },
  209. { "mcp4552-502", MCP455x_502 },
  210. { "mcp4552-103", MCP455x_103 },
  211. { "mcp4552-503", MCP455x_503 },
  212. { "mcp4552-104", MCP455x_104 },
  213. { "mcp4561-502", MCP456x_502 },
  214. { "mcp4561-103", MCP456x_103 },
  215. { "mcp4561-503", MCP456x_503 },
  216. { "mcp4561-104", MCP456x_104 },
  217. { "mcp4562-502", MCP456x_502 },
  218. { "mcp4562-103", MCP456x_103 },
  219. { "mcp4562-503", MCP456x_503 },
  220. { "mcp4562-104", MCP456x_104 },
  221. { "mcp4631-502", MCP463x_502 },
  222. { "mcp4631-103", MCP463x_103 },
  223. { "mcp4631-503", MCP463x_503 },
  224. { "mcp4631-104", MCP463x_104 },
  225. { "mcp4632-502", MCP463x_502 },
  226. { "mcp4632-103", MCP463x_103 },
  227. { "mcp4632-503", MCP463x_503 },
  228. { "mcp4632-104", MCP463x_104 },
  229. { "mcp4641-502", MCP464x_502 },
  230. { "mcp4641-103", MCP464x_103 },
  231. { "mcp4641-503", MCP464x_503 },
  232. { "mcp4641-104", MCP464x_104 },
  233. { "mcp4642-502", MCP464x_502 },
  234. { "mcp4642-103", MCP464x_103 },
  235. { "mcp4642-503", MCP464x_503 },
  236. { "mcp4642-104", MCP464x_104 },
  237. { "mcp4651-502", MCP465x_502 },
  238. { "mcp4651-103", MCP465x_103 },
  239. { "mcp4651-503", MCP465x_503 },
  240. { "mcp4651-104", MCP465x_104 },
  241. { "mcp4652-502", MCP465x_502 },
  242. { "mcp4652-103", MCP465x_103 },
  243. { "mcp4652-503", MCP465x_503 },
  244. { "mcp4652-104", MCP465x_104 },
  245. { "mcp4661-502", MCP466x_502 },
  246. { "mcp4661-103", MCP466x_103 },
  247. { "mcp4661-503", MCP466x_503 },
  248. { "mcp4661-104", MCP466x_104 },
  249. { "mcp4662-502", MCP466x_502 },
  250. { "mcp4662-103", MCP466x_103 },
  251. { "mcp4662-503", MCP466x_503 },
  252. { "mcp4662-104", MCP466x_104 },
  253. {}
  254. };
  255. MODULE_DEVICE_TABLE(i2c, mcp4531_id);
  256. #define MCP4531_COMPATIBLE(of_compatible, cfg) { \
  257. .compatible = of_compatible, \
  258. .data = &mcp4531_cfg[cfg], \
  259. }
  260. static const struct of_device_id mcp4531_of_match[] = {
  261. MCP4531_COMPATIBLE("microchip,mcp4531-502", MCP453x_502),
  262. MCP4531_COMPATIBLE("microchip,mcp4531-103", MCP453x_103),
  263. MCP4531_COMPATIBLE("microchip,mcp4531-503", MCP453x_503),
  264. MCP4531_COMPATIBLE("microchip,mcp4531-104", MCP453x_104),
  265. MCP4531_COMPATIBLE("microchip,mcp4532-502", MCP453x_502),
  266. MCP4531_COMPATIBLE("microchip,mcp4532-103", MCP453x_103),
  267. MCP4531_COMPATIBLE("microchip,mcp4532-503", MCP453x_503),
  268. MCP4531_COMPATIBLE("microchip,mcp4532-104", MCP453x_104),
  269. MCP4531_COMPATIBLE("microchip,mcp4541-502", MCP454x_502),
  270. MCP4531_COMPATIBLE("microchip,mcp4541-103", MCP454x_103),
  271. MCP4531_COMPATIBLE("microchip,mcp4541-503", MCP454x_503),
  272. MCP4531_COMPATIBLE("microchip,mcp4541-104", MCP454x_104),
  273. MCP4531_COMPATIBLE("microchip,mcp4542-502", MCP454x_502),
  274. MCP4531_COMPATIBLE("microchip,mcp4542-103", MCP454x_103),
  275. MCP4531_COMPATIBLE("microchip,mcp4542-503", MCP454x_503),
  276. MCP4531_COMPATIBLE("microchip,mcp4542-104", MCP454x_104),
  277. MCP4531_COMPATIBLE("microchip,mcp4551-502", MCP455x_502),
  278. MCP4531_COMPATIBLE("microchip,mcp4551-103", MCP455x_103),
  279. MCP4531_COMPATIBLE("microchip,mcp4551-503", MCP455x_503),
  280. MCP4531_COMPATIBLE("microchip,mcp4551-104", MCP455x_104),
  281. MCP4531_COMPATIBLE("microchip,mcp4552-502", MCP455x_502),
  282. MCP4531_COMPATIBLE("microchip,mcp4552-103", MCP455x_103),
  283. MCP4531_COMPATIBLE("microchip,mcp4552-503", MCP455x_503),
  284. MCP4531_COMPATIBLE("microchip,mcp4552-104", MCP455x_104),
  285. MCP4531_COMPATIBLE("microchip,mcp4561-502", MCP456x_502),
  286. MCP4531_COMPATIBLE("microchip,mcp4561-103", MCP456x_103),
  287. MCP4531_COMPATIBLE("microchip,mcp4561-503", MCP456x_503),
  288. MCP4531_COMPATIBLE("microchip,mcp4561-104", MCP456x_104),
  289. MCP4531_COMPATIBLE("microchip,mcp4562-502", MCP456x_502),
  290. MCP4531_COMPATIBLE("microchip,mcp4562-103", MCP456x_103),
  291. MCP4531_COMPATIBLE("microchip,mcp4562-503", MCP456x_503),
  292. MCP4531_COMPATIBLE("microchip,mcp4562-104", MCP456x_104),
  293. MCP4531_COMPATIBLE("microchip,mcp4631-502", MCP463x_502),
  294. MCP4531_COMPATIBLE("microchip,mcp4631-103", MCP463x_103),
  295. MCP4531_COMPATIBLE("microchip,mcp4631-503", MCP463x_503),
  296. MCP4531_COMPATIBLE("microchip,mcp4631-104", MCP463x_104),
  297. MCP4531_COMPATIBLE("microchip,mcp4632-502", MCP463x_502),
  298. MCP4531_COMPATIBLE("microchip,mcp4632-103", MCP463x_103),
  299. MCP4531_COMPATIBLE("microchip,mcp4632-503", MCP463x_503),
  300. MCP4531_COMPATIBLE("microchip,mcp4632-104", MCP463x_104),
  301. MCP4531_COMPATIBLE("microchip,mcp4641-502", MCP464x_502),
  302. MCP4531_COMPATIBLE("microchip,mcp4641-103", MCP464x_103),
  303. MCP4531_COMPATIBLE("microchip,mcp4641-503", MCP464x_503),
  304. MCP4531_COMPATIBLE("microchip,mcp4641-104", MCP464x_104),
  305. MCP4531_COMPATIBLE("microchip,mcp4642-502", MCP464x_502),
  306. MCP4531_COMPATIBLE("microchip,mcp4642-103", MCP464x_103),
  307. MCP4531_COMPATIBLE("microchip,mcp4642-503", MCP464x_503),
  308. MCP4531_COMPATIBLE("microchip,mcp4642-104", MCP464x_104),
  309. MCP4531_COMPATIBLE("microchip,mcp4651-502", MCP465x_502),
  310. MCP4531_COMPATIBLE("microchip,mcp4651-103", MCP465x_103),
  311. MCP4531_COMPATIBLE("microchip,mcp4651-503", MCP465x_503),
  312. MCP4531_COMPATIBLE("microchip,mcp4651-104", MCP465x_104),
  313. MCP4531_COMPATIBLE("microchip,mcp4652-502", MCP465x_502),
  314. MCP4531_COMPATIBLE("microchip,mcp4652-103", MCP465x_103),
  315. MCP4531_COMPATIBLE("microchip,mcp4652-503", MCP465x_503),
  316. MCP4531_COMPATIBLE("microchip,mcp4652-104", MCP465x_104),
  317. MCP4531_COMPATIBLE("microchip,mcp4661-502", MCP466x_502),
  318. MCP4531_COMPATIBLE("microchip,mcp4661-103", MCP466x_103),
  319. MCP4531_COMPATIBLE("microchip,mcp4661-503", MCP466x_503),
  320. MCP4531_COMPATIBLE("microchip,mcp4661-104", MCP466x_104),
  321. MCP4531_COMPATIBLE("microchip,mcp4662-502", MCP466x_502),
  322. MCP4531_COMPATIBLE("microchip,mcp4662-103", MCP466x_103),
  323. MCP4531_COMPATIBLE("microchip,mcp4662-503", MCP466x_503),
  324. MCP4531_COMPATIBLE("microchip,mcp4662-104", MCP466x_104),
  325. { /* sentinel */ }
  326. };
  327. MODULE_DEVICE_TABLE(of, mcp4531_of_match);
  328. static int mcp4531_probe(struct i2c_client *client)
  329. {
  330. struct device *dev = &client->dev;
  331. struct mcp4531_data *data;
  332. struct iio_dev *indio_dev;
  333. if (!i2c_check_functionality(client->adapter,
  334. I2C_FUNC_SMBUS_WORD_DATA)) {
  335. dev_err(dev, "SMBUS Word Data not supported\n");
  336. return -EOPNOTSUPP;
  337. }
  338. indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
  339. if (!indio_dev)
  340. return -ENOMEM;
  341. data = iio_priv(indio_dev);
  342. i2c_set_clientdata(client, indio_dev);
  343. data->client = client;
  344. data->cfg = device_get_match_data(dev);
  345. if (!data->cfg)
  346. data->cfg = &mcp4531_cfg[i2c_match_id(mcp4531_id, client)->driver_data];
  347. indio_dev->info = &mcp4531_info;
  348. indio_dev->channels = mcp4531_channels;
  349. indio_dev->num_channels = data->cfg->wipers;
  350. indio_dev->name = client->name;
  351. return devm_iio_device_register(dev, indio_dev);
  352. }
  353. static struct i2c_driver mcp4531_driver = {
  354. .driver = {
  355. .name = "mcp4531",
  356. .of_match_table = mcp4531_of_match,
  357. },
  358. .probe_new = mcp4531_probe,
  359. .id_table = mcp4531_id,
  360. };
  361. module_i2c_driver(mcp4531_driver);
  362. MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
  363. MODULE_DESCRIPTION("MCP4531 digital potentiometer");
  364. MODULE_LICENSE("GPL v2");