max77686.c 16 KB

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  1. /*
  2. * max77686.c - Regulator driver for the Maxim 77686
  3. *
  4. * Copyright (C) 2012 Samsung Electronics
  5. * Chiwoong Byun <woong.byun@smasung.com>
  6. * Jonghwa Lee <jonghwa3.lee@samsung.com>
  7. *
  8. * This program is free software; you can redistribute it and/or modify
  9. * it under the terms of the GNU General Public License as published by
  10. * the Free Software Foundation; either version 2 of the License, or
  11. * (at your option) any later version.
  12. *
  13. * This program is distributed in the hope that it will be useful,
  14. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. * GNU General Public License for more details.
  17. *
  18. * You should have received a copy of the GNU General Public License
  19. * along with this program; if not, write to the Free Software
  20. * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21. *
  22. * This driver is based on max8997.c
  23. */
  24. #include <linux/kernel.h>
  25. #include <linux/bug.h>
  26. #include <linux/delay.h>
  27. #include <linux/err.h>
  28. #include <linux/gpio.h>
  29. #include <linux/slab.h>
  30. #include <linux/platform_device.h>
  31. #include <linux/regulator/driver.h>
  32. #include <linux/regulator/machine.h>
  33. #include <linux/regulator/of_regulator.h>
  34. #include <linux/mfd/max77686.h>
  35. #include <linux/mfd/max77686-private.h>
  36. #define MAX77686_LDO_MINUV 800000
  37. #define MAX77686_LDO_UVSTEP 50000
  38. #define MAX77686_LDO_LOW_MINUV 800000
  39. #define MAX77686_LDO_LOW_UVSTEP 25000
  40. #define MAX77686_BUCK_MINUV 750000
  41. #define MAX77686_BUCK_UVSTEP 50000
  42. #define MAX77686_RAMP_DELAY 100000 /* uV/us */
  43. #define MAX77686_DVS_RAMP_DELAY 27500 /* uV/us */
  44. #define MAX77686_DVS_MINUV 600000
  45. #define MAX77686_DVS_UVSTEP 12500
  46. #define MAX77686_OPMODE_SHIFT 6
  47. #define MAX77686_OPMODE_BUCK234_SHIFT 4
  48. #define MAX77686_OPMODE_MASK 0x3
  49. #define MAX77686_VSEL_MASK 0x3F
  50. #define MAX77686_DVS_VSEL_MASK 0xFF
  51. #define MAX77686_RAMP_RATE_MASK 0xC0
  52. #define MAX77686_REGULATORS MAX77686_REG_MAX
  53. #define MAX77686_LDOS 26
  54. enum max77686_ramp_rate {
  55. RAMP_RATE_13P75MV,
  56. RAMP_RATE_27P5MV,
  57. RAMP_RATE_55MV,
  58. RAMP_RATE_NO_CTRL, /* 100mV/us */
  59. };
  60. struct max77686_data {
  61. struct regulator_dev *rdev[MAX77686_REGULATORS];
  62. unsigned int opmode[MAX77686_REGULATORS];
  63. };
  64. /* Some BUCKS supports Normal[ON/OFF] mode during suspend */
  65. static int max77686_buck_set_suspend_disable(struct regulator_dev *rdev)
  66. {
  67. unsigned int val;
  68. struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  69. if (rdev->desc->id == MAX77686_BUCK1)
  70. val = 0x1;
  71. else
  72. val = 0x1 << MAX77686_OPMODE_BUCK234_SHIFT;
  73. max77686->opmode[rdev->desc->id] = val;
  74. return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  75. rdev->desc->enable_mask,
  76. val);
  77. }
  78. /* Some LDOs supports [LPM/Normal]ON mode during suspend state */
  79. static int max77686_set_suspend_mode(struct regulator_dev *rdev,
  80. unsigned int mode)
  81. {
  82. struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  83. unsigned int val;
  84. /* BUCK[5-9] doesn't support this feature */
  85. if (rdev->desc->id >= MAX77686_BUCK5)
  86. return 0;
  87. switch (mode) {
  88. case REGULATOR_MODE_IDLE: /* ON in LP Mode */
  89. val = 0x2 << MAX77686_OPMODE_SHIFT;
  90. break;
  91. case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
  92. val = 0x3 << MAX77686_OPMODE_SHIFT;
  93. break;
  94. default:
  95. pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
  96. rdev->desc->name, mode);
  97. return -EINVAL;
  98. }
  99. max77686->opmode[rdev->desc->id] = val;
  100. return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  101. rdev->desc->enable_mask,
  102. val);
  103. }
  104. /* Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state */
  105. static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
  106. unsigned int mode)
  107. {
  108. unsigned int val;
  109. struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  110. switch (mode) {
  111. case REGULATOR_MODE_STANDBY: /* switch off */
  112. val = 0x1 << MAX77686_OPMODE_SHIFT;
  113. break;
  114. case REGULATOR_MODE_IDLE: /* ON in LP Mode */
  115. val = 0x2 << MAX77686_OPMODE_SHIFT;
  116. break;
  117. case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
  118. val = 0x3 << MAX77686_OPMODE_SHIFT;
  119. break;
  120. default:
  121. pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
  122. rdev->desc->name, mode);
  123. return -EINVAL;
  124. }
  125. max77686->opmode[rdev->desc->id] = val;
  126. return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  127. rdev->desc->enable_mask,
  128. val);
  129. }
  130. static int max77686_enable(struct regulator_dev *rdev)
  131. {
  132. struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  133. return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  134. rdev->desc->enable_mask,
  135. max77686->opmode[rdev->desc->id]);
  136. }
  137. static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
  138. {
  139. unsigned int ramp_value = RAMP_RATE_NO_CTRL;
  140. switch (ramp_delay) {
  141. case 1 ... 13750:
  142. ramp_value = RAMP_RATE_13P75MV;
  143. break;
  144. case 13751 ... 27500:
  145. ramp_value = RAMP_RATE_27P5MV;
  146. break;
  147. case 27501 ... 55000:
  148. ramp_value = RAMP_RATE_55MV;
  149. break;
  150. case 55001 ... 100000:
  151. break;
  152. default:
  153. pr_warn("%s: ramp_delay: %d not supported, setting 100000\n",
  154. rdev->desc->name, ramp_delay);
  155. }
  156. return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  157. MAX77686_RAMP_RATE_MASK, ramp_value << 6);
  158. }
  159. static struct regulator_ops max77686_ops = {
  160. .list_voltage = regulator_list_voltage_linear,
  161. .map_voltage = regulator_map_voltage_linear,
  162. .is_enabled = regulator_is_enabled_regmap,
  163. .enable = max77686_enable,
  164. .disable = regulator_disable_regmap,
  165. .get_voltage_sel = regulator_get_voltage_sel_regmap,
  166. .set_voltage_sel = regulator_set_voltage_sel_regmap,
  167. .set_voltage_time_sel = regulator_set_voltage_time_sel,
  168. .set_suspend_mode = max77686_set_suspend_mode,
  169. };
  170. static struct regulator_ops max77686_ldo_ops = {
  171. .list_voltage = regulator_list_voltage_linear,
  172. .map_voltage = regulator_map_voltage_linear,
  173. .is_enabled = regulator_is_enabled_regmap,
  174. .enable = max77686_enable,
  175. .disable = regulator_disable_regmap,
  176. .get_voltage_sel = regulator_get_voltage_sel_regmap,
  177. .set_voltage_sel = regulator_set_voltage_sel_regmap,
  178. .set_voltage_time_sel = regulator_set_voltage_time_sel,
  179. .set_suspend_mode = max77686_ldo_set_suspend_mode,
  180. };
  181. static struct regulator_ops max77686_buck1_ops = {
  182. .list_voltage = regulator_list_voltage_linear,
  183. .map_voltage = regulator_map_voltage_linear,
  184. .is_enabled = regulator_is_enabled_regmap,
  185. .enable = max77686_enable,
  186. .disable = regulator_disable_regmap,
  187. .get_voltage_sel = regulator_get_voltage_sel_regmap,
  188. .set_voltage_sel = regulator_set_voltage_sel_regmap,
  189. .set_voltage_time_sel = regulator_set_voltage_time_sel,
  190. .set_suspend_disable = max77686_buck_set_suspend_disable,
  191. };
  192. static struct regulator_ops max77686_buck_dvs_ops = {
  193. .list_voltage = regulator_list_voltage_linear,
  194. .map_voltage = regulator_map_voltage_linear,
  195. .is_enabled = regulator_is_enabled_regmap,
  196. .enable = max77686_enable,
  197. .disable = regulator_disable_regmap,
  198. .get_voltage_sel = regulator_get_voltage_sel_regmap,
  199. .set_voltage_sel = regulator_set_voltage_sel_regmap,
  200. .set_voltage_time_sel = regulator_set_voltage_time_sel,
  201. .set_ramp_delay = max77686_set_ramp_delay,
  202. .set_suspend_disable = max77686_buck_set_suspend_disable,
  203. };
  204. #define regulator_desc_ldo(num) { \
  205. .name = "LDO"#num, \
  206. .id = MAX77686_LDO##num, \
  207. .ops = &max77686_ops, \
  208. .type = REGULATOR_VOLTAGE, \
  209. .owner = THIS_MODULE, \
  210. .min_uV = MAX77686_LDO_MINUV, \
  211. .uV_step = MAX77686_LDO_UVSTEP, \
  212. .ramp_delay = MAX77686_RAMP_DELAY, \
  213. .n_voltages = MAX77686_VSEL_MASK + 1, \
  214. .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  215. .vsel_mask = MAX77686_VSEL_MASK, \
  216. .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  217. .enable_mask = MAX77686_OPMODE_MASK \
  218. << MAX77686_OPMODE_SHIFT, \
  219. }
  220. #define regulator_desc_lpm_ldo(num) { \
  221. .name = "LDO"#num, \
  222. .id = MAX77686_LDO##num, \
  223. .ops = &max77686_ldo_ops, \
  224. .type = REGULATOR_VOLTAGE, \
  225. .owner = THIS_MODULE, \
  226. .min_uV = MAX77686_LDO_MINUV, \
  227. .uV_step = MAX77686_LDO_UVSTEP, \
  228. .ramp_delay = MAX77686_RAMP_DELAY, \
  229. .n_voltages = MAX77686_VSEL_MASK + 1, \
  230. .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  231. .vsel_mask = MAX77686_VSEL_MASK, \
  232. .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  233. .enable_mask = MAX77686_OPMODE_MASK \
  234. << MAX77686_OPMODE_SHIFT, \
  235. }
  236. #define regulator_desc_ldo_low(num) { \
  237. .name = "LDO"#num, \
  238. .id = MAX77686_LDO##num, \
  239. .ops = &max77686_ldo_ops, \
  240. .type = REGULATOR_VOLTAGE, \
  241. .owner = THIS_MODULE, \
  242. .min_uV = MAX77686_LDO_LOW_MINUV, \
  243. .uV_step = MAX77686_LDO_LOW_UVSTEP, \
  244. .ramp_delay = MAX77686_RAMP_DELAY, \
  245. .n_voltages = MAX77686_VSEL_MASK + 1, \
  246. .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  247. .vsel_mask = MAX77686_VSEL_MASK, \
  248. .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  249. .enable_mask = MAX77686_OPMODE_MASK \
  250. << MAX77686_OPMODE_SHIFT, \
  251. }
  252. #define regulator_desc_ldo1_low(num) { \
  253. .name = "LDO"#num, \
  254. .id = MAX77686_LDO##num, \
  255. .ops = &max77686_ops, \
  256. .type = REGULATOR_VOLTAGE, \
  257. .owner = THIS_MODULE, \
  258. .min_uV = MAX77686_LDO_LOW_MINUV, \
  259. .uV_step = MAX77686_LDO_LOW_UVSTEP, \
  260. .ramp_delay = MAX77686_RAMP_DELAY, \
  261. .n_voltages = MAX77686_VSEL_MASK + 1, \
  262. .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  263. .vsel_mask = MAX77686_VSEL_MASK, \
  264. .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
  265. .enable_mask = MAX77686_OPMODE_MASK \
  266. << MAX77686_OPMODE_SHIFT, \
  267. }
  268. #define regulator_desc_buck(num) { \
  269. .name = "BUCK"#num, \
  270. .id = MAX77686_BUCK##num, \
  271. .ops = &max77686_ops, \
  272. .type = REGULATOR_VOLTAGE, \
  273. .owner = THIS_MODULE, \
  274. .min_uV = MAX77686_BUCK_MINUV, \
  275. .uV_step = MAX77686_BUCK_UVSTEP, \
  276. .ramp_delay = MAX77686_RAMP_DELAY, \
  277. .n_voltages = MAX77686_VSEL_MASK + 1, \
  278. .vsel_reg = MAX77686_REG_BUCK5OUT + (num - 5) * 2, \
  279. .vsel_mask = MAX77686_VSEL_MASK, \
  280. .enable_reg = MAX77686_REG_BUCK5CTRL + (num - 5) * 2, \
  281. .enable_mask = MAX77686_OPMODE_MASK, \
  282. }
  283. #define regulator_desc_buck1(num) { \
  284. .name = "BUCK"#num, \
  285. .id = MAX77686_BUCK##num, \
  286. .ops = &max77686_buck1_ops, \
  287. .type = REGULATOR_VOLTAGE, \
  288. .owner = THIS_MODULE, \
  289. .min_uV = MAX77686_BUCK_MINUV, \
  290. .uV_step = MAX77686_BUCK_UVSTEP, \
  291. .ramp_delay = MAX77686_RAMP_DELAY, \
  292. .n_voltages = MAX77686_VSEL_MASK + 1, \
  293. .vsel_reg = MAX77686_REG_BUCK1OUT, \
  294. .vsel_mask = MAX77686_VSEL_MASK, \
  295. .enable_reg = MAX77686_REG_BUCK1CTRL, \
  296. .enable_mask = MAX77686_OPMODE_MASK, \
  297. }
  298. #define regulator_desc_buck_dvs(num) { \
  299. .name = "BUCK"#num, \
  300. .id = MAX77686_BUCK##num, \
  301. .ops = &max77686_buck_dvs_ops, \
  302. .type = REGULATOR_VOLTAGE, \
  303. .owner = THIS_MODULE, \
  304. .min_uV = MAX77686_DVS_MINUV, \
  305. .uV_step = MAX77686_DVS_UVSTEP, \
  306. .ramp_delay = MAX77686_DVS_RAMP_DELAY, \
  307. .n_voltages = MAX77686_DVS_VSEL_MASK + 1, \
  308. .vsel_reg = MAX77686_REG_BUCK2DVS1 + (num - 2) * 10, \
  309. .vsel_mask = MAX77686_DVS_VSEL_MASK, \
  310. .enable_reg = MAX77686_REG_BUCK2CTRL1 + (num - 2) * 10, \
  311. .enable_mask = MAX77686_OPMODE_MASK \
  312. << MAX77686_OPMODE_BUCK234_SHIFT, \
  313. }
  314. static struct regulator_desc regulators[] = {
  315. regulator_desc_ldo1_low(1),
  316. regulator_desc_ldo_low(2),
  317. regulator_desc_ldo(3),
  318. regulator_desc_ldo(4),
  319. regulator_desc_ldo(5),
  320. regulator_desc_ldo_low(6),
  321. regulator_desc_ldo_low(7),
  322. regulator_desc_ldo_low(8),
  323. regulator_desc_ldo(9),
  324. regulator_desc_lpm_ldo(10),
  325. regulator_desc_lpm_ldo(11),
  326. regulator_desc_lpm_ldo(12),
  327. regulator_desc_ldo(13),
  328. regulator_desc_lpm_ldo(14),
  329. regulator_desc_ldo_low(15),
  330. regulator_desc_lpm_ldo(16),
  331. regulator_desc_ldo(17),
  332. regulator_desc_ldo(18),
  333. regulator_desc_ldo(19),
  334. regulator_desc_ldo(20),
  335. regulator_desc_ldo(21),
  336. regulator_desc_ldo(22),
  337. regulator_desc_ldo(23),
  338. regulator_desc_ldo(24),
  339. regulator_desc_ldo(25),
  340. regulator_desc_ldo(26),
  341. regulator_desc_buck1(1),
  342. regulator_desc_buck_dvs(2),
  343. regulator_desc_buck_dvs(3),
  344. regulator_desc_buck_dvs(4),
  345. regulator_desc_buck(5),
  346. regulator_desc_buck(6),
  347. regulator_desc_buck(7),
  348. regulator_desc_buck(8),
  349. regulator_desc_buck(9),
  350. };
  351. #ifdef CONFIG_OF
  352. static int max77686_pmic_dt_parse_pdata(struct max77686_dev *iodev,
  353. struct max77686_platform_data *pdata)
  354. {
  355. struct device_node *pmic_np, *regulators_np;
  356. struct max77686_regulator_data *rdata;
  357. struct of_regulator_match rmatch;
  358. unsigned int i;
  359. pmic_np = iodev->dev->of_node;
  360. regulators_np = of_find_node_by_name(pmic_np, "voltage-regulators");
  361. if (!regulators_np) {
  362. dev_err(iodev->dev, "could not find regulators sub-node\n");
  363. return -EINVAL;
  364. }
  365. pdata->num_regulators = ARRAY_SIZE(regulators);
  366. rdata = devm_kzalloc(iodev->dev, sizeof(*rdata) *
  367. pdata->num_regulators, GFP_KERNEL);
  368. if (!rdata) {
  369. dev_err(iodev->dev,
  370. "could not allocate memory for regulator data\n");
  371. return -ENOMEM;
  372. }
  373. for (i = 0; i < pdata->num_regulators; i++) {
  374. rmatch.name = regulators[i].name;
  375. rmatch.init_data = NULL;
  376. rmatch.of_node = NULL;
  377. of_regulator_match(iodev->dev, regulators_np, &rmatch, 1);
  378. rdata[i].initdata = rmatch.init_data;
  379. rdata[i].of_node = rmatch.of_node;
  380. }
  381. pdata->regulators = rdata;
  382. return 0;
  383. }
  384. #else
  385. static int max77686_pmic_dt_parse_pdata(struct max77686_dev *iodev,
  386. struct max77686_platform_data *pdata)
  387. {
  388. return 0;
  389. }
  390. #endif /* CONFIG_OF */
  391. static int max77686_pmic_probe(struct platform_device *pdev)
  392. {
  393. struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
  394. struct max77686_platform_data *pdata = dev_get_platdata(iodev->dev);
  395. struct max77686_data *max77686;
  396. int i, ret = 0;
  397. struct regulator_config config = { };
  398. dev_dbg(&pdev->dev, "%s\n", __func__);
  399. if (!pdata) {
  400. dev_err(&pdev->dev, "no platform data found for regulator\n");
  401. return -ENODEV;
  402. }
  403. if (iodev->dev->of_node) {
  404. ret = max77686_pmic_dt_parse_pdata(iodev, pdata);
  405. if (ret)
  406. return ret;
  407. }
  408. if (pdata->num_regulators != MAX77686_REGULATORS) {
  409. dev_err(&pdev->dev,
  410. "Invalid initial data for regulator's initialiation\n");
  411. return -EINVAL;
  412. }
  413. max77686 = devm_kzalloc(&pdev->dev, sizeof(struct max77686_data),
  414. GFP_KERNEL);
  415. if (!max77686)
  416. return -ENOMEM;
  417. config.dev = &pdev->dev;
  418. config.regmap = iodev->regmap;
  419. config.driver_data = max77686;
  420. platform_set_drvdata(pdev, max77686);
  421. for (i = 0; i < MAX77686_REGULATORS; i++) {
  422. config.init_data = pdata->regulators[i].initdata;
  423. config.of_node = pdata->regulators[i].of_node;
  424. max77686->opmode[i] = regulators[i].enable_mask;
  425. max77686->rdev[i] = regulator_register(&regulators[i], &config);
  426. if (IS_ERR(max77686->rdev[i])) {
  427. ret = PTR_ERR(max77686->rdev[i]);
  428. dev_err(&pdev->dev,
  429. "regulator init failed for %d\n", i);
  430. max77686->rdev[i] = NULL;
  431. goto err;
  432. }
  433. }
  434. return 0;
  435. err:
  436. while (--i >= 0)
  437. regulator_unregister(max77686->rdev[i]);
  438. return ret;
  439. }
  440. static int max77686_pmic_remove(struct platform_device *pdev)
  441. {
  442. struct max77686_data *max77686 = platform_get_drvdata(pdev);
  443. int i;
  444. for (i = 0; i < MAX77686_REGULATORS; i++)
  445. regulator_unregister(max77686->rdev[i]);
  446. return 0;
  447. }
  448. static const struct platform_device_id max77686_pmic_id[] = {
  449. {"max77686-pmic", 0},
  450. { },
  451. };
  452. MODULE_DEVICE_TABLE(platform, max77686_pmic_id);
  453. static struct platform_driver max77686_pmic_driver = {
  454. .driver = {
  455. .name = "max77686-pmic",
  456. .owner = THIS_MODULE,
  457. },
  458. .probe = max77686_pmic_probe,
  459. .remove = max77686_pmic_remove,
  460. .id_table = max77686_pmic_id,
  461. };
  462. static int __init max77686_pmic_init(void)
  463. {
  464. return platform_driver_register(&max77686_pmic_driver);
  465. }
  466. subsys_initcall(max77686_pmic_init);
  467. static void __exit max77686_pmic_cleanup(void)
  468. {
  469. platform_driver_unregister(&max77686_pmic_driver);
  470. }
  471. module_exit(max77686_pmic_cleanup);
  472. MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
  473. MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
  474. MODULE_LICENSE("GPL");