wm8994-core.c 15 KB

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  1. /*
  2. * wm8994-core.c -- Device access for Wolfson WM8994
  3. *
  4. * Copyright 2009 Wolfson Microelectronics PLC.
  5. *
  6. * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  7. *
  8. * This program is free software; you can redistribute it and/or modify it
  9. * under the terms of the GNU General Public License as published by the
  10. * Free Software Foundation; either version 2 of the License, or (at your
  11. * option) any later version.
  12. *
  13. */
  14. #include <linux/kernel.h>
  15. #include <linux/module.h>
  16. #include <linux/slab.h>
  17. #include <linux/i2c.h>
  18. #include <linux/err.h>
  19. #include <linux/delay.h>
  20. #include <linux/mfd/core.h>
  21. #include <linux/pm_runtime.h>
  22. #include <linux/regmap.h>
  23. #include <linux/regulator/consumer.h>
  24. #include <linux/regulator/machine.h>
  25. #include <linux/mfd/wm8994/core.h>
  26. #include <linux/mfd/wm8994/pdata.h>
  27. #include <linux/mfd/wm8994/registers.h>
  28. #include "wm8994.h"
  29. /**
  30. * wm8994_reg_read: Read a single WM8994 register.
  31. *
  32. * @wm8994: Device to read from.
  33. * @reg: Register to read.
  34. */
  35. int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
  36. {
  37. unsigned int val;
  38. int ret;
  39. ret = regmap_read(wm8994->regmap, reg, &val);
  40. if (ret < 0)
  41. return ret;
  42. else
  43. return val;
  44. }
  45. EXPORT_SYMBOL_GPL(wm8994_reg_read);
  46. /**
  47. * wm8994_bulk_read: Read multiple WM8994 registers
  48. *
  49. * @wm8994: Device to read from
  50. * @reg: First register
  51. * @count: Number of registers
  52. * @buf: Buffer to fill. The data will be returned big endian.
  53. */
  54. int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
  55. int count, u16 *buf)
  56. {
  57. return regmap_bulk_read(wm8994->regmap, reg, buf, count);
  58. }
  59. /**
  60. * wm8994_reg_write: Write a single WM8994 register.
  61. *
  62. * @wm8994: Device to write to.
  63. * @reg: Register to write to.
  64. * @val: Value to write.
  65. */
  66. int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
  67. unsigned short val)
  68. {
  69. return regmap_write(wm8994->regmap, reg, val);
  70. }
  71. EXPORT_SYMBOL_GPL(wm8994_reg_write);
  72. /**
  73. * wm8994_bulk_write: Write multiple WM8994 registers
  74. *
  75. * @wm8994: Device to write to
  76. * @reg: First register
  77. * @count: Number of registers
  78. * @buf: Buffer to write from. Data must be big-endian formatted.
  79. */
  80. int wm8994_bulk_write(struct wm8994 *wm8994, unsigned short reg,
  81. int count, const u16 *buf)
  82. {
  83. return regmap_raw_write(wm8994->regmap, reg, buf, count * sizeof(u16));
  84. }
  85. EXPORT_SYMBOL_GPL(wm8994_bulk_write);
  86. /**
  87. * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
  88. *
  89. * @wm8994: Device to write to.
  90. * @reg: Register to write to.
  91. * @mask: Mask of bits to set.
  92. * @val: Value to set (unshifted)
  93. */
  94. int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
  95. unsigned short mask, unsigned short val)
  96. {
  97. return regmap_update_bits(wm8994->regmap, reg, mask, val);
  98. }
  99. EXPORT_SYMBOL_GPL(wm8994_set_bits);
  100. static struct mfd_cell wm8994_regulator_devs[] = {
  101. {
  102. .name = "wm8994-ldo",
  103. .id = 1,
  104. .pm_runtime_no_callbacks = true,
  105. },
  106. {
  107. .name = "wm8994-ldo",
  108. .id = 2,
  109. .pm_runtime_no_callbacks = true,
  110. },
  111. };
  112. static struct resource wm8994_codec_resources[] = {
  113. {
  114. .start = WM8994_IRQ_TEMP_SHUT,
  115. .end = WM8994_IRQ_TEMP_WARN,
  116. .flags = IORESOURCE_IRQ,
  117. },
  118. };
  119. static struct resource wm8994_gpio_resources[] = {
  120. {
  121. .start = WM8994_IRQ_GPIO(1),
  122. .end = WM8994_IRQ_GPIO(11),
  123. .flags = IORESOURCE_IRQ,
  124. },
  125. };
  126. static struct mfd_cell wm8994_devs[] = {
  127. {
  128. .name = "wm8994-codec",
  129. .num_resources = ARRAY_SIZE(wm8994_codec_resources),
  130. .resources = wm8994_codec_resources,
  131. },
  132. {
  133. .name = "wm8994-gpio",
  134. .num_resources = ARRAY_SIZE(wm8994_gpio_resources),
  135. .resources = wm8994_gpio_resources,
  136. .pm_runtime_no_callbacks = true,
  137. },
  138. };
  139. /*
  140. * Supplies for the main bulk of CODEC; the LDO supplies are ignored
  141. * and should be handled via the standard regulator API supply
  142. * management.
  143. */
  144. static const char *wm1811_main_supplies[] = {
  145. "DBVDD1",
  146. "DBVDD2",
  147. "DBVDD3",
  148. "DCVDD",
  149. "AVDD1",
  150. "AVDD2",
  151. "CPVDD",
  152. "SPKVDD1",
  153. "SPKVDD2",
  154. };
  155. static const char *wm8994_main_supplies[] = {
  156. "DBVDD",
  157. "DCVDD",
  158. "AVDD1",
  159. "AVDD2",
  160. "CPVDD",
  161. "SPKVDD1",
  162. "SPKVDD2",
  163. };
  164. static const char *wm8958_main_supplies[] = {
  165. "DBVDD1",
  166. "DBVDD2",
  167. "DBVDD3",
  168. "DCVDD",
  169. "AVDD1",
  170. "AVDD2",
  171. "CPVDD",
  172. "SPKVDD1",
  173. "SPKVDD2",
  174. };
  175. #ifdef CONFIG_PM
  176. static int wm8994_suspend(struct device *dev)
  177. {
  178. struct wm8994 *wm8994 = dev_get_drvdata(dev);
  179. int ret;
  180. /* Don't actually go through with the suspend if the CODEC is
  181. * still active (eg, for audio passthrough from CP. */
  182. ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_1);
  183. if (ret < 0) {
  184. dev_err(dev, "Failed to read power status: %d\n", ret);
  185. } else if (ret & WM8994_VMID_SEL_MASK) {
  186. dev_dbg(dev, "CODEC still active, ignoring suspend\n");
  187. return 0;
  188. }
  189. ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_4);
  190. if (ret < 0) {
  191. dev_err(dev, "Failed to read power status: %d\n", ret);
  192. } else if (ret & (WM8994_AIF2ADCL_ENA | WM8994_AIF2ADCR_ENA |
  193. WM8994_AIF1ADC2L_ENA | WM8994_AIF1ADC2R_ENA |
  194. WM8994_AIF1ADC1L_ENA | WM8994_AIF1ADC1R_ENA)) {
  195. dev_dbg(dev, "CODEC still active, ignoring suspend\n");
  196. return 0;
  197. }
  198. ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_5);
  199. if (ret < 0) {
  200. dev_err(dev, "Failed to read power status: %d\n", ret);
  201. } else if (ret & (WM8994_AIF2DACL_ENA | WM8994_AIF2DACR_ENA |
  202. WM8994_AIF1DAC2L_ENA | WM8994_AIF1DAC2R_ENA |
  203. WM8994_AIF1DAC1L_ENA | WM8994_AIF1DAC1R_ENA)) {
  204. dev_dbg(dev, "CODEC still active, ignoring suspend\n");
  205. return 0;
  206. }
  207. switch (wm8994->type) {
  208. case WM8958:
  209. ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1);
  210. if (ret < 0) {
  211. dev_err(dev, "Failed to read power status: %d\n", ret);
  212. } else if (ret & WM8958_MICD_ENA) {
  213. dev_dbg(dev, "CODEC still active, ignoring suspend\n");
  214. return 0;
  215. }
  216. break;
  217. default:
  218. break;
  219. }
  220. /* Disable LDO pulldowns while the device is suspended if we
  221. * don't know that something will be driving them. */
  222. if (!wm8994->ldo_ena_always_driven)
  223. wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
  224. WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
  225. WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
  226. /* Explicitly put the device into reset in case regulators
  227. * don't get disabled in order to ensure consistent restart.
  228. */
  229. wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
  230. wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
  231. regcache_mark_dirty(wm8994->regmap);
  232. wm8994->suspended = true;
  233. ret = regulator_bulk_disable(wm8994->num_supplies,
  234. wm8994->supplies);
  235. if (ret != 0) {
  236. dev_err(dev, "Failed to disable supplies: %d\n", ret);
  237. return ret;
  238. }
  239. return 0;
  240. }
  241. static int wm8994_resume(struct device *dev)
  242. {
  243. struct wm8994 *wm8994 = dev_get_drvdata(dev);
  244. int ret;
  245. /* We may have lied to the PM core about suspending */
  246. if (!wm8994->suspended)
  247. return 0;
  248. ret = regulator_bulk_enable(wm8994->num_supplies,
  249. wm8994->supplies);
  250. if (ret != 0) {
  251. dev_err(dev, "Failed to enable supplies: %d\n", ret);
  252. return ret;
  253. }
  254. ret = regcache_sync(wm8994->regmap);
  255. if (ret != 0) {
  256. dev_err(dev, "Failed to restore register map: %d\n", ret);
  257. goto err_enable;
  258. }
  259. /* Disable LDO pulldowns while the device is active */
  260. wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
  261. WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
  262. 0);
  263. wm8994->suspended = false;
  264. return 0;
  265. err_enable:
  266. regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies);
  267. return ret;
  268. }
  269. #endif
  270. #ifdef CONFIG_REGULATOR
  271. static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
  272. {
  273. struct wm8994_ldo_pdata *ldo_pdata;
  274. if (!pdata)
  275. return 0;
  276. ldo_pdata = &pdata->ldo[ldo];
  277. if (!ldo_pdata->init_data)
  278. return 0;
  279. return ldo_pdata->init_data->num_consumer_supplies != 0;
  280. }
  281. #else
  282. static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
  283. {
  284. return 0;
  285. }
  286. #endif
  287. /*
  288. * Instantiate the generic non-control parts of the device.
  289. */
  290. static int wm8994_device_init(struct wm8994 *wm8994, int irq)
  291. {
  292. struct wm8994_pdata *pdata = wm8994->dev->platform_data;
  293. struct regmap_config *regmap_config;
  294. const char *devname;
  295. int ret, i;
  296. int pulls = 0;
  297. dev_set_drvdata(wm8994->dev, wm8994);
  298. /* Add the on-chip regulators first for bootstrapping */
  299. ret = mfd_add_devices(wm8994->dev, -1,
  300. wm8994_regulator_devs,
  301. ARRAY_SIZE(wm8994_regulator_devs),
  302. NULL, 0);
  303. if (ret != 0) {
  304. dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
  305. goto err_regmap;
  306. }
  307. switch (wm8994->type) {
  308. case WM1811:
  309. wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies);
  310. break;
  311. case WM8994:
  312. wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
  313. break;
  314. case WM8958:
  315. wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
  316. break;
  317. default:
  318. BUG();
  319. goto err_regmap;
  320. }
  321. wm8994->supplies = devm_kzalloc(wm8994->dev,
  322. sizeof(struct regulator_bulk_data) *
  323. wm8994->num_supplies, GFP_KERNEL);
  324. if (!wm8994->supplies) {
  325. ret = -ENOMEM;
  326. goto err_regmap;
  327. }
  328. switch (wm8994->type) {
  329. case WM1811:
  330. for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++)
  331. wm8994->supplies[i].supply = wm1811_main_supplies[i];
  332. break;
  333. case WM8994:
  334. for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
  335. wm8994->supplies[i].supply = wm8994_main_supplies[i];
  336. break;
  337. case WM8958:
  338. for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
  339. wm8994->supplies[i].supply = wm8958_main_supplies[i];
  340. break;
  341. default:
  342. BUG();
  343. goto err_regmap;
  344. }
  345. ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
  346. wm8994->supplies);
  347. if (ret != 0) {
  348. dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
  349. goto err_regmap;
  350. }
  351. ret = regulator_bulk_enable(wm8994->num_supplies,
  352. wm8994->supplies);
  353. if (ret != 0) {
  354. dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
  355. goto err_get;
  356. }
  357. ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
  358. if (ret < 0) {
  359. dev_err(wm8994->dev, "Failed to read ID register\n");
  360. goto err_enable;
  361. }
  362. switch (ret) {
  363. case 0x1811:
  364. devname = "WM1811";
  365. if (wm8994->type != WM1811)
  366. dev_warn(wm8994->dev, "Device registered as type %d\n",
  367. wm8994->type);
  368. wm8994->type = WM1811;
  369. break;
  370. case 0x8994:
  371. devname = "WM8994";
  372. if (wm8994->type != WM8994)
  373. dev_warn(wm8994->dev, "Device registered as type %d\n",
  374. wm8994->type);
  375. wm8994->type = WM8994;
  376. break;
  377. case 0x8958:
  378. devname = "WM8958";
  379. if (wm8994->type != WM8958)
  380. dev_warn(wm8994->dev, "Device registered as type %d\n",
  381. wm8994->type);
  382. wm8994->type = WM8958;
  383. break;
  384. default:
  385. dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
  386. ret);
  387. ret = -EINVAL;
  388. goto err_enable;
  389. }
  390. ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
  391. if (ret < 0) {
  392. dev_err(wm8994->dev, "Failed to read revision register: %d\n",
  393. ret);
  394. goto err_enable;
  395. }
  396. wm8994->revision = ret;
  397. switch (wm8994->type) {
  398. case WM8994:
  399. switch (wm8994->revision) {
  400. case 0:
  401. case 1:
  402. dev_warn(wm8994->dev,
  403. "revision %c not fully supported\n",
  404. 'A' + wm8994->revision);
  405. break;
  406. default:
  407. break;
  408. }
  409. break;
  410. case WM1811:
  411. /* Revision C did not change the relevant layer */
  412. if (wm8994->revision > 1)
  413. wm8994->revision++;
  414. break;
  415. default:
  416. break;
  417. }
  418. dev_info(wm8994->dev, "%s revision %c\n", devname,
  419. 'A' + wm8994->revision);
  420. switch (wm8994->type) {
  421. case WM1811:
  422. regmap_config = &wm1811_regmap_config;
  423. break;
  424. case WM8994:
  425. regmap_config = &wm8994_regmap_config;
  426. break;
  427. case WM8958:
  428. regmap_config = &wm8958_regmap_config;
  429. break;
  430. default:
  431. dev_err(wm8994->dev, "Unknown device type %d\n", wm8994->type);
  432. return -EINVAL;
  433. }
  434. ret = regmap_reinit_cache(wm8994->regmap, regmap_config);
  435. if (ret != 0) {
  436. dev_err(wm8994->dev, "Failed to reinit register cache: %d\n",
  437. ret);
  438. return ret;
  439. }
  440. if (pdata) {
  441. wm8994->irq_base = pdata->irq_base;
  442. wm8994->gpio_base = pdata->gpio_base;
  443. /* GPIO configuration is only applied if it's non-zero */
  444. for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
  445. if (pdata->gpio_defaults[i]) {
  446. wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
  447. 0xffff,
  448. pdata->gpio_defaults[i]);
  449. }
  450. }
  451. wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;
  452. if (pdata->spkmode_pu)
  453. pulls |= WM8994_SPKMODE_PU;
  454. }
  455. /* Disable unneeded pulls */
  456. wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
  457. WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD |
  458. WM8994_SPKMODE_PU | WM8994_CSNADDR_PD,
  459. pulls);
  460. /* In some system designs where the regulators are not in use,
  461. * we can achieve a small reduction in leakage currents by
  462. * floating LDO outputs. This bit makes no difference if the
  463. * LDOs are enabled, it only affects cases where the LDOs were
  464. * in operation and are then disabled.
  465. */
  466. for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
  467. if (wm8994_ldo_in_use(pdata, i))
  468. wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
  469. WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
  470. else
  471. wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
  472. WM8994_LDO1_DISCH, 0);
  473. }
  474. wm8994_irq_init(wm8994);
  475. ret = mfd_add_devices(wm8994->dev, -1,
  476. wm8994_devs, ARRAY_SIZE(wm8994_devs),
  477. NULL, 0);
  478. if (ret != 0) {
  479. dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
  480. goto err_irq;
  481. }
  482. pm_runtime_enable(wm8994->dev);
  483. pm_runtime_resume(wm8994->dev);
  484. return 0;
  485. err_irq:
  486. wm8994_irq_exit(wm8994);
  487. err_enable:
  488. regulator_bulk_disable(wm8994->num_supplies,
  489. wm8994->supplies);
  490. err_get:
  491. regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
  492. err_regmap:
  493. regmap_exit(wm8994->regmap);
  494. mfd_remove_devices(wm8994->dev);
  495. return ret;
  496. }
  497. static void wm8994_device_exit(struct wm8994 *wm8994)
  498. {
  499. pm_runtime_disable(wm8994->dev);
  500. mfd_remove_devices(wm8994->dev);
  501. wm8994_irq_exit(wm8994);
  502. regulator_bulk_disable(wm8994->num_supplies,
  503. wm8994->supplies);
  504. regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
  505. regmap_exit(wm8994->regmap);
  506. }
  507. static const struct of_device_id wm8994_of_match[] = {
  508. { .compatible = "wlf,wm1811", },
  509. { .compatible = "wlf,wm8994", },
  510. { .compatible = "wlf,wm8958", },
  511. { }
  512. };
  513. MODULE_DEVICE_TABLE(of, wm8994_of_match);
  514. static int wm8994_i2c_probe(struct i2c_client *i2c,
  515. const struct i2c_device_id *id)
  516. {
  517. struct wm8994 *wm8994;
  518. int ret;
  519. wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL);
  520. if (wm8994 == NULL)
  521. return -ENOMEM;
  522. i2c_set_clientdata(i2c, wm8994);
  523. wm8994->dev = &i2c->dev;
  524. wm8994->irq = i2c->irq;
  525. wm8994->type = id->driver_data;
  526. wm8994->regmap = regmap_init_i2c(i2c, &wm8994_base_regmap_config);
  527. if (IS_ERR(wm8994->regmap)) {
  528. ret = PTR_ERR(wm8994->regmap);
  529. dev_err(wm8994->dev, "Failed to allocate register map: %d\n",
  530. ret);
  531. return ret;
  532. }
  533. return wm8994_device_init(wm8994, i2c->irq);
  534. }
  535. static int wm8994_i2c_remove(struct i2c_client *i2c)
  536. {
  537. struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
  538. wm8994_device_exit(wm8994);
  539. return 0;
  540. }
  541. static const struct i2c_device_id wm8994_i2c_id[] = {
  542. { "wm1811", WM1811 },
  543. { "wm1811a", WM1811 },
  544. { "wm8994", WM8994 },
  545. { "wm8958", WM8958 },
  546. { }
  547. };
  548. MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
  549. static UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume,
  550. NULL);
  551. static struct i2c_driver wm8994_i2c_driver = {
  552. .driver = {
  553. .name = "wm8994",
  554. .owner = THIS_MODULE,
  555. .pm = &wm8994_pm_ops,
  556. .of_match_table = wm8994_of_match,
  557. },
  558. .probe = wm8994_i2c_probe,
  559. .remove = wm8994_i2c_remove,
  560. .id_table = wm8994_i2c_id,
  561. };
  562. static int __init wm8994_i2c_init(void)
  563. {
  564. int ret;
  565. ret = i2c_add_driver(&wm8994_i2c_driver);
  566. if (ret != 0)
  567. pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
  568. return ret;
  569. }
  570. module_init(wm8994_i2c_init);
  571. static void __exit wm8994_i2c_exit(void)
  572. {
  573. i2c_del_driver(&wm8994_i2c_driver);
  574. }
  575. module_exit(wm8994_i2c_exit);
  576. MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
  577. MODULE_LICENSE("GPL");
  578. MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");