qt1050.c 15 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * Microchip AT42QT1050 QTouch Sensor Controller
  4. *
  5. * Copyright (C) 2019 Pengutronix, Marco Felsch <kernel@pengutronix.de>
  6. *
  7. * Base on AT42QT1070 driver by:
  8. * Bo Shen <voice.shen@atmel.com>
  9. * Copyright (C) 2011 Atmel
  10. */
  11. #include <linux/delay.h>
  12. #include <linux/i2c.h>
  13. #include <linux/input.h>
  14. #include <linux/interrupt.h>
  15. #include <linux/kernel.h>
  16. #include <linux/log2.h>
  17. #include <linux/module.h>
  18. #include <linux/of.h>
  19. #include <linux/regmap.h>
  20. /* Chip ID */
  21. #define QT1050_CHIP_ID 0x00
  22. #define QT1050_CHIP_ID_VER 0x46
  23. /* Firmware version */
  24. #define QT1050_FW_VERSION 0x01
  25. /* Detection status */
  26. #define QT1050_DET_STATUS 0x02
  27. /* Key status */
  28. #define QT1050_KEY_STATUS 0x03
  29. /* Key Signals */
  30. #define QT1050_KEY_SIGNAL_0_MSB 0x06
  31. #define QT1050_KEY_SIGNAL_0_LSB 0x07
  32. #define QT1050_KEY_SIGNAL_1_MSB 0x08
  33. #define QT1050_KEY_SIGNAL_1_LSB 0x09
  34. #define QT1050_KEY_SIGNAL_2_MSB 0x0c
  35. #define QT1050_KEY_SIGNAL_2_LSB 0x0d
  36. #define QT1050_KEY_SIGNAL_3_MSB 0x0e
  37. #define QT1050_KEY_SIGNAL_3_LSB 0x0f
  38. #define QT1050_KEY_SIGNAL_4_MSB 0x10
  39. #define QT1050_KEY_SIGNAL_4_LSB 0x11
  40. /* Reference data */
  41. #define QT1050_REF_DATA_0_MSB 0x14
  42. #define QT1050_REF_DATA_0_LSB 0x15
  43. #define QT1050_REF_DATA_1_MSB 0x16
  44. #define QT1050_REF_DATA_1_LSB 0x17
  45. #define QT1050_REF_DATA_2_MSB 0x1a
  46. #define QT1050_REF_DATA_2_LSB 0x1b
  47. #define QT1050_REF_DATA_3_MSB 0x1c
  48. #define QT1050_REF_DATA_3_LSB 0x1d
  49. #define QT1050_REF_DATA_4_MSB 0x1e
  50. #define QT1050_REF_DATA_4_LSB 0x1f
  51. /* Negative threshold level */
  52. #define QT1050_NTHR_0 0x21
  53. #define QT1050_NTHR_1 0x22
  54. #define QT1050_NTHR_2 0x24
  55. #define QT1050_NTHR_3 0x25
  56. #define QT1050_NTHR_4 0x26
  57. /* Pulse / Scale */
  58. #define QT1050_PULSE_SCALE_0 0x28
  59. #define QT1050_PULSE_SCALE_1 0x29
  60. #define QT1050_PULSE_SCALE_2 0x2b
  61. #define QT1050_PULSE_SCALE_3 0x2c
  62. #define QT1050_PULSE_SCALE_4 0x2d
  63. /* Detection integrator counter / AKS */
  64. #define QT1050_DI_AKS_0 0x2f
  65. #define QT1050_DI_AKS_1 0x30
  66. #define QT1050_DI_AKS_2 0x32
  67. #define QT1050_DI_AKS_3 0x33
  68. #define QT1050_DI_AKS_4 0x34
  69. /* Charge Share Delay */
  70. #define QT1050_CSD_0 0x36
  71. #define QT1050_CSD_1 0x37
  72. #define QT1050_CSD_2 0x39
  73. #define QT1050_CSD_3 0x3a
  74. #define QT1050_CSD_4 0x3b
  75. /* Low Power Mode */
  76. #define QT1050_LPMODE 0x3d
  77. /* Calibration and Reset */
  78. #define QT1050_RES_CAL 0x3f
  79. #define QT1050_RES_CAL_RESET BIT(7)
  80. #define QT1050_RES_CAL_CALIBRATE BIT(1)
  81. #define QT1050_MAX_KEYS 5
  82. #define QT1050_RESET_TIME 255
  83. struct qt1050_key_regs {
  84. unsigned int nthr;
  85. unsigned int pulse_scale;
  86. unsigned int di_aks;
  87. unsigned int csd;
  88. };
  89. struct qt1050_key {
  90. u32 num;
  91. u32 charge_delay;
  92. u32 thr_cnt;
  93. u32 samples;
  94. u32 scale;
  95. u32 keycode;
  96. };
  97. struct qt1050_priv {
  98. struct i2c_client *client;
  99. struct input_dev *input;
  100. struct regmap *regmap;
  101. struct qt1050_key keys[QT1050_MAX_KEYS];
  102. unsigned short keycodes[QT1050_MAX_KEYS];
  103. u8 reg_keys;
  104. u8 last_keys;
  105. };
  106. static const struct qt1050_key_regs qt1050_key_regs_data[] = {
  107. {
  108. .nthr = QT1050_NTHR_0,
  109. .pulse_scale = QT1050_PULSE_SCALE_0,
  110. .di_aks = QT1050_DI_AKS_0,
  111. .csd = QT1050_CSD_0,
  112. }, {
  113. .nthr = QT1050_NTHR_1,
  114. .pulse_scale = QT1050_PULSE_SCALE_1,
  115. .di_aks = QT1050_DI_AKS_1,
  116. .csd = QT1050_CSD_1,
  117. }, {
  118. .nthr = QT1050_NTHR_2,
  119. .pulse_scale = QT1050_PULSE_SCALE_2,
  120. .di_aks = QT1050_DI_AKS_2,
  121. .csd = QT1050_CSD_2,
  122. }, {
  123. .nthr = QT1050_NTHR_3,
  124. .pulse_scale = QT1050_PULSE_SCALE_3,
  125. .di_aks = QT1050_DI_AKS_3,
  126. .csd = QT1050_CSD_3,
  127. }, {
  128. .nthr = QT1050_NTHR_4,
  129. .pulse_scale = QT1050_PULSE_SCALE_4,
  130. .di_aks = QT1050_DI_AKS_4,
  131. .csd = QT1050_CSD_4,
  132. }
  133. };
  134. static bool qt1050_volatile_reg(struct device *dev, unsigned int reg)
  135. {
  136. switch (reg) {
  137. case QT1050_DET_STATUS:
  138. case QT1050_KEY_STATUS:
  139. case QT1050_KEY_SIGNAL_0_MSB:
  140. case QT1050_KEY_SIGNAL_0_LSB:
  141. case QT1050_KEY_SIGNAL_1_MSB:
  142. case QT1050_KEY_SIGNAL_1_LSB:
  143. case QT1050_KEY_SIGNAL_2_MSB:
  144. case QT1050_KEY_SIGNAL_2_LSB:
  145. case QT1050_KEY_SIGNAL_3_MSB:
  146. case QT1050_KEY_SIGNAL_3_LSB:
  147. case QT1050_KEY_SIGNAL_4_MSB:
  148. case QT1050_KEY_SIGNAL_4_LSB:
  149. return true;
  150. default:
  151. return false;
  152. }
  153. }
  154. static const struct regmap_range qt1050_readable_ranges[] = {
  155. regmap_reg_range(QT1050_CHIP_ID, QT1050_KEY_STATUS),
  156. regmap_reg_range(QT1050_KEY_SIGNAL_0_MSB, QT1050_KEY_SIGNAL_1_LSB),
  157. regmap_reg_range(QT1050_KEY_SIGNAL_2_MSB, QT1050_KEY_SIGNAL_4_LSB),
  158. regmap_reg_range(QT1050_REF_DATA_0_MSB, QT1050_REF_DATA_1_LSB),
  159. regmap_reg_range(QT1050_REF_DATA_2_MSB, QT1050_REF_DATA_4_LSB),
  160. regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1),
  161. regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4),
  162. regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1),
  163. regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4),
  164. regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1),
  165. regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4),
  166. regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1),
  167. regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL),
  168. };
  169. static const struct regmap_access_table qt1050_readable_table = {
  170. .yes_ranges = qt1050_readable_ranges,
  171. .n_yes_ranges = ARRAY_SIZE(qt1050_readable_ranges),
  172. };
  173. static const struct regmap_range qt1050_writeable_ranges[] = {
  174. regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1),
  175. regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4),
  176. regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1),
  177. regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4),
  178. regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1),
  179. regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4),
  180. regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1),
  181. regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL),
  182. };
  183. static const struct regmap_access_table qt1050_writeable_table = {
  184. .yes_ranges = qt1050_writeable_ranges,
  185. .n_yes_ranges = ARRAY_SIZE(qt1050_writeable_ranges),
  186. };
  187. static struct regmap_config qt1050_regmap_config = {
  188. .reg_bits = 8,
  189. .val_bits = 8,
  190. .max_register = QT1050_RES_CAL,
  191. .cache_type = REGCACHE_RBTREE,
  192. .wr_table = &qt1050_writeable_table,
  193. .rd_table = &qt1050_readable_table,
  194. .volatile_reg = qt1050_volatile_reg,
  195. };
  196. static bool qt1050_identify(struct qt1050_priv *ts)
  197. {
  198. unsigned int val;
  199. int err;
  200. /* Read Chip ID */
  201. regmap_read(ts->regmap, QT1050_CHIP_ID, &val);
  202. if (val != QT1050_CHIP_ID_VER) {
  203. dev_err(&ts->client->dev, "ID %d not supported\n", val);
  204. return false;
  205. }
  206. /* Read firmware version */
  207. err = regmap_read(ts->regmap, QT1050_FW_VERSION, &val);
  208. if (err) {
  209. dev_err(&ts->client->dev, "could not read the firmware version\n");
  210. return false;
  211. }
  212. dev_info(&ts->client->dev, "AT42QT1050 firmware version %1d.%1d\n",
  213. val >> 4, val & 0xf);
  214. return true;
  215. }
  216. static irqreturn_t qt1050_irq_threaded(int irq, void *dev_id)
  217. {
  218. struct qt1050_priv *ts = dev_id;
  219. struct input_dev *input = ts->input;
  220. unsigned long new_keys, changed;
  221. unsigned int val;
  222. int i, err;
  223. /* Read the detected status register, thus clearing interrupt */
  224. err = regmap_read(ts->regmap, QT1050_DET_STATUS, &val);
  225. if (err) {
  226. dev_err(&ts->client->dev, "Fail to read detection status: %d\n",
  227. err);
  228. return IRQ_NONE;
  229. }
  230. /* Read which key changed, keys are not continuous */
  231. err = regmap_read(ts->regmap, QT1050_KEY_STATUS, &val);
  232. if (err) {
  233. dev_err(&ts->client->dev,
  234. "Fail to determine the key status: %d\n", err);
  235. return IRQ_NONE;
  236. }
  237. new_keys = (val & 0x70) >> 2 | (val & 0x6) >> 1;
  238. changed = ts->last_keys ^ new_keys;
  239. /* Report registered keys only */
  240. changed &= ts->reg_keys;
  241. for_each_set_bit(i, &changed, QT1050_MAX_KEYS)
  242. input_report_key(input, ts->keys[i].keycode,
  243. test_bit(i, &new_keys));
  244. ts->last_keys = new_keys;
  245. input_sync(input);
  246. return IRQ_HANDLED;
  247. }
  248. static const struct qt1050_key_regs *qt1050_get_key_regs(int key_num)
  249. {
  250. return &qt1050_key_regs_data[key_num];
  251. }
  252. static int qt1050_set_key(struct regmap *map, int number, int on)
  253. {
  254. const struct qt1050_key_regs *key_regs;
  255. key_regs = qt1050_get_key_regs(number);
  256. return regmap_update_bits(map, key_regs->di_aks, 0xfc,
  257. on ? BIT(4) : 0x00);
  258. }
  259. static int qt1050_apply_fw_data(struct qt1050_priv *ts)
  260. {
  261. struct regmap *map = ts->regmap;
  262. struct qt1050_key *button = &ts->keys[0];
  263. const struct qt1050_key_regs *key_regs;
  264. int i, err;
  265. /* Disable all keys and enable only the specified ones */
  266. for (i = 0; i < QT1050_MAX_KEYS; i++) {
  267. err = qt1050_set_key(map, i, 0);
  268. if (err)
  269. return err;
  270. }
  271. for (i = 0; i < QT1050_MAX_KEYS; i++, button++) {
  272. /* Keep KEY_RESERVED keys off */
  273. if (button->keycode == KEY_RESERVED)
  274. continue;
  275. err = qt1050_set_key(map, button->num, 1);
  276. if (err)
  277. return err;
  278. key_regs = qt1050_get_key_regs(button->num);
  279. err = regmap_write(map, key_regs->pulse_scale,
  280. (button->samples << 4) | (button->scale));
  281. if (err)
  282. return err;
  283. err = regmap_write(map, key_regs->csd, button->charge_delay);
  284. if (err)
  285. return err;
  286. err = regmap_write(map, key_regs->nthr, button->thr_cnt);
  287. if (err)
  288. return err;
  289. }
  290. return 0;
  291. }
  292. static int qt1050_parse_fw(struct qt1050_priv *ts)
  293. {
  294. struct device *dev = &ts->client->dev;
  295. struct fwnode_handle *child;
  296. int nbuttons;
  297. nbuttons = device_get_child_node_count(dev);
  298. if (nbuttons == 0 || nbuttons > QT1050_MAX_KEYS)
  299. return -ENODEV;
  300. device_for_each_child_node(dev, child) {
  301. struct qt1050_key button;
  302. /* Required properties */
  303. if (fwnode_property_read_u32(child, "linux,code",
  304. &button.keycode)) {
  305. dev_err(dev, "Button without keycode\n");
  306. goto err;
  307. }
  308. if (button.keycode >= KEY_MAX) {
  309. dev_err(dev, "Invalid keycode 0x%x\n",
  310. button.keycode);
  311. goto err;
  312. }
  313. if (fwnode_property_read_u32(child, "reg",
  314. &button.num)) {
  315. dev_err(dev, "Button without pad number\n");
  316. goto err;
  317. }
  318. if (button.num < 0 || button.num > QT1050_MAX_KEYS - 1)
  319. goto err;
  320. ts->reg_keys |= BIT(button.num);
  321. /* Optional properties */
  322. if (fwnode_property_read_u32(child,
  323. "microchip,pre-charge-time-ns",
  324. &button.charge_delay)) {
  325. button.charge_delay = 0;
  326. } else {
  327. if (button.charge_delay % 2500 == 0)
  328. button.charge_delay =
  329. button.charge_delay / 2500;
  330. else
  331. button.charge_delay = 0;
  332. }
  333. if (fwnode_property_read_u32(child, "microchip,average-samples",
  334. &button.samples)) {
  335. button.samples = 0;
  336. } else {
  337. if (is_power_of_2(button.samples))
  338. button.samples = ilog2(button.samples);
  339. else
  340. button.samples = 0;
  341. }
  342. if (fwnode_property_read_u32(child, "microchip,average-scaling",
  343. &button.scale)) {
  344. button.scale = 0;
  345. } else {
  346. if (is_power_of_2(button.scale))
  347. button.scale = ilog2(button.scale);
  348. else
  349. button.scale = 0;
  350. }
  351. if (fwnode_property_read_u32(child, "microchip,threshold",
  352. &button.thr_cnt)) {
  353. button.thr_cnt = 20;
  354. } else {
  355. if (button.thr_cnt > 255)
  356. button.thr_cnt = 20;
  357. }
  358. ts->keys[button.num] = button;
  359. }
  360. return 0;
  361. err:
  362. fwnode_handle_put(child);
  363. return -EINVAL;
  364. }
  365. static int qt1050_probe(struct i2c_client *client)
  366. {
  367. struct qt1050_priv *ts;
  368. struct input_dev *input;
  369. struct device *dev = &client->dev;
  370. struct regmap *map;
  371. unsigned int status, i;
  372. int err;
  373. /* Check basic functionality */
  374. err = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE);
  375. if (!err) {
  376. dev_err(&client->dev, "%s adapter not supported\n",
  377. dev_driver_string(&client->adapter->dev));
  378. return -ENODEV;
  379. }
  380. if (!client->irq) {
  381. dev_err(dev, "assign a irq line to this device\n");
  382. return -EINVAL;
  383. }
  384. ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
  385. if (!ts)
  386. return -ENOMEM;
  387. input = devm_input_allocate_device(dev);
  388. if (!input)
  389. return -ENOMEM;
  390. map = devm_regmap_init_i2c(client, &qt1050_regmap_config);
  391. if (IS_ERR(map))
  392. return PTR_ERR(map);
  393. ts->client = client;
  394. ts->input = input;
  395. ts->regmap = map;
  396. i2c_set_clientdata(client, ts);
  397. /* Identify the qt1050 chip */
  398. if (!qt1050_identify(ts))
  399. return -ENODEV;
  400. /* Get pdata */
  401. err = qt1050_parse_fw(ts);
  402. if (err) {
  403. dev_err(dev, "Failed to parse firmware: %d\n", err);
  404. return err;
  405. }
  406. input->name = "AT42QT1050 QTouch Sensor";
  407. input->dev.parent = &client->dev;
  408. input->id.bustype = BUS_I2C;
  409. /* Add the keycode */
  410. input->keycode = ts->keycodes;
  411. input->keycodesize = sizeof(ts->keycodes[0]);
  412. input->keycodemax = QT1050_MAX_KEYS;
  413. __set_bit(EV_KEY, input->evbit);
  414. for (i = 0; i < QT1050_MAX_KEYS; i++) {
  415. ts->keycodes[i] = ts->keys[i].keycode;
  416. __set_bit(ts->keycodes[i], input->keybit);
  417. }
  418. /* Trigger re-calibration */
  419. err = regmap_update_bits(ts->regmap, QT1050_RES_CAL, 0x7f,
  420. QT1050_RES_CAL_CALIBRATE);
  421. if (err) {
  422. dev_err(dev, "Trigger calibration failed: %d\n", err);
  423. return err;
  424. }
  425. err = regmap_read_poll_timeout(ts->regmap, QT1050_DET_STATUS, status,
  426. status >> 7 == 1, 10000, 200000);
  427. if (err) {
  428. dev_err(dev, "Calibration failed: %d\n", err);
  429. return err;
  430. }
  431. /* Soft reset to set defaults */
  432. err = regmap_update_bits(ts->regmap, QT1050_RES_CAL,
  433. QT1050_RES_CAL_RESET, QT1050_RES_CAL_RESET);
  434. if (err) {
  435. dev_err(dev, "Trigger soft reset failed: %d\n", err);
  436. return err;
  437. }
  438. msleep(QT1050_RESET_TIME);
  439. /* Set pdata */
  440. err = qt1050_apply_fw_data(ts);
  441. if (err) {
  442. dev_err(dev, "Failed to set firmware data: %d\n", err);
  443. return err;
  444. }
  445. err = devm_request_threaded_irq(dev, client->irq, NULL,
  446. qt1050_irq_threaded, IRQF_ONESHOT,
  447. "qt1050", ts);
  448. if (err) {
  449. dev_err(&client->dev, "Failed to request irq: %d\n", err);
  450. return err;
  451. }
  452. /* Clear #CHANGE line */
  453. err = regmap_read(ts->regmap, QT1050_DET_STATUS, &status);
  454. if (err) {
  455. dev_err(dev, "Failed to clear #CHANGE line level: %d\n", err);
  456. return err;
  457. }
  458. /* Register the input device */
  459. err = input_register_device(ts->input);
  460. if (err) {
  461. dev_err(&client->dev, "Failed to register input device: %d\n",
  462. err);
  463. return err;
  464. }
  465. return 0;
  466. }
  467. static int __maybe_unused qt1050_suspend(struct device *dev)
  468. {
  469. struct i2c_client *client = to_i2c_client(dev);
  470. struct qt1050_priv *ts = i2c_get_clientdata(client);
  471. disable_irq(client->irq);
  472. /*
  473. * Set measurement interval to 1s (125 x 8ms) if wakeup is allowed
  474. * else turn off. The 1s interval seems to be a good compromise between
  475. * low power and response time.
  476. */
  477. return regmap_write(ts->regmap, QT1050_LPMODE,
  478. device_may_wakeup(dev) ? 125 : 0);
  479. }
  480. static int __maybe_unused qt1050_resume(struct device *dev)
  481. {
  482. struct i2c_client *client = to_i2c_client(dev);
  483. struct qt1050_priv *ts = i2c_get_clientdata(client);
  484. enable_irq(client->irq);
  485. /* Set measurement interval back to 16ms (2 x 8ms) */
  486. return regmap_write(ts->regmap, QT1050_LPMODE, 2);
  487. }
  488. static SIMPLE_DEV_PM_OPS(qt1050_pm_ops, qt1050_suspend, qt1050_resume);
  489. static const struct of_device_id __maybe_unused qt1050_of_match[] = {
  490. { .compatible = "microchip,qt1050", },
  491. { },
  492. };
  493. MODULE_DEVICE_TABLE(of, qt1050_of_match);
  494. static struct i2c_driver qt1050_driver = {
  495. .driver = {
  496. .name = "qt1050",
  497. .of_match_table = of_match_ptr(qt1050_of_match),
  498. .pm = &qt1050_pm_ops,
  499. },
  500. .probe_new = qt1050_probe,
  501. };
  502. module_i2c_driver(qt1050_driver);
  503. MODULE_AUTHOR("Marco Felsch <kernel@pengutronix.de");
  504. MODULE_DESCRIPTION("Driver for AT42QT1050 QTouch sensor");
  505. MODULE_LICENSE("GPL v2");