/drivers/regulator/max8649.c

https://bitbucket.org/cyanogenmod/android_kernel_asus_tf300t · C · 409 lines · 324 code · 61 blank · 24 comment · 24 complexity · 54cd97ce369008ed3170912a063a685a MD5 · raw file 

    

  1. /*
    2. 

  2.  * Regulators driver for Maxim max8649
    3. 

  3.  *
    4. 

  4.  * Copyright (C) 2009-2010 Marvell International Ltd.
    5. 

  5.  *      Haojian Zhuang <haojian.zhuang@marvell.com>
    6. 

  6.  *
    7. 

  7.  * This program is free software; you can redistribute it and/or modify
    8. 

  8.  * it under the terms of the GNU General Public License version 2 as
    9. 

  9.  * published by the Free Software Foundation.
    10. 

  10.  */
    11. 

  11. #include <linux/kernel.h>
    12. 

  12. #include <linux/module.h>
    13. 

  13. #include <linux/err.h>
    14. 

  14. #include <linux/i2c.h>
    15. 

  15. #include <linux/platform_device.h>
    16. 

  16. #include <linux/regulator/driver.h>
    17. 

  17. #include <linux/slab.h>
    18. 

  18. #include <linux/regulator/max8649.h>
    19. 

  19. 

  20. #define MAX8649_DCDC_VMIN	750000		/* uV */
    21. 

  21. #define MAX8649_DCDC_VMAX	1380000		/* uV */
    22. 

  22. #define MAX8649_DCDC_STEP	10000		/* uV */
    23. 

  23. #define MAX8649_VOL_MASK	0x3f
    24. 

  24. 

  25. /* Registers */
    26. 

  26. #define MAX8649_MODE0		0x00
    27. 

  27. #define MAX8649_MODE1		0x01
    28. 

  28. #define MAX8649_MODE2		0x02
    29. 

  29. #define MAX8649_MODE3		0x03
    30. 

  30. #define MAX8649_CONTROL		0x04
    31. 

  31. #define MAX8649_SYNC		0x05
    32. 

  32. #define MAX8649_RAMP		0x06
    33. 

  33. #define MAX8649_CHIP_ID1	0x08
    34. 

  34. #define MAX8649_CHIP_ID2	0x09
    35. 

  35. 

  36. /* Bits */
    37. 

  37. #define MAX8649_EN_PD		(1 << 7)
    38. 

  38. #define MAX8649_VID0_PD		(1 << 6)
    39. 

  39. #define MAX8649_VID1_PD		(1 << 5)
    40. 

  40. #define MAX8649_VID_MASK	(3 << 5)
    41. 

  41. 

  42. #define MAX8649_FORCE_PWM	(1 << 7)
    43. 

  43. #define MAX8649_SYNC_EXTCLK	(1 << 6)
    44. 

  44. 

  45. #define MAX8649_EXT_MASK	(3 << 6)
    46. 

  46. 

  47. #define MAX8649_RAMP_MASK	(7 << 5)
    48. 

  48. #define MAX8649_RAMP_DOWN	(1 << 1)
    49. 

  49. 

  50. struct max8649_regulator_info {
    51. 

  51. 	struct regulator_dev	*regulator;
    52. 

  52. 	struct i2c_client	*i2c;
    53. 

  53. 	struct device		*dev;
    54. 

  54. 	struct mutex		io_lock;
    55. 

  55. 

  56. 	int		vol_reg;
    57. 

  57. 	unsigned	mode:2;	/* bit[1:0] = VID1, VID0 */
    58. 

  58. 	unsigned	extclk_freq:2;
    59. 

  59. 	unsigned	extclk:1;
    60. 

  60. 	unsigned	ramp_timing:3;
    61. 

  61. 	unsigned	ramp_down:1;
    62. 

  62. };
    63. 

  63. 

  64. /* I2C operations */
    65. 

  65. 

  66. static inline int max8649_read_device(struct i2c_client *i2c,
    67. 

  67. 				      int reg, int bytes, void *dest)
    68. 

  68. {
    69. 

  69. 	unsigned char data;
    70. 

  70. 	int ret;
    71. 

  71. 

  72. 	data = (unsigned char)reg;
    73. 

  73. 	ret = i2c_master_send(i2c, &data, 1);
    74. 

  74. 	if (ret < 0)
    75. 

  75. 		return ret;
    76. 

  76. 	ret = i2c_master_recv(i2c, dest, bytes);
    77. 

  77. 	if (ret < 0)
    78. 

  78. 		return ret;
    79. 

  79. 	return 0;
    80. 

  80. }
    81. 

  81. 

  82. static inline int max8649_write_device(struct i2c_client *i2c,
    83. 

  83. 				       int reg, int bytes, void *src)
    84. 

  84. {
    85. 

  85. 	unsigned char buf[bytes + 1];
    86. 

  86. 	int ret;
    87. 

  87. 

  88. 	buf[0] = (unsigned char)reg;
    89. 

  89. 	memcpy(&buf[1], src, bytes);
    90. 

  90. 

  91. 	ret = i2c_master_send(i2c, buf, bytes + 1);
    92. 

  92. 	if (ret < 0)
    93. 

  93. 		return ret;
    94. 

  94. 	return 0;
    95. 

  95. }
    96. 

  96. 

  97. static int max8649_reg_read(struct i2c_client *i2c, int reg)
    98. 

  98. {
    99. 

  99. 	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
    100. 

  100. 	unsigned char data;
    101. 

  101. 	int ret;
    102. 

  102. 

  103. 	mutex_lock(&info->io_lock);
    104. 

  104. 	ret = max8649_read_device(i2c, reg, 1, &data);
    105. 

  105. 	mutex_unlock(&info->io_lock);
    106. 

  106. 

  107. 	if (ret < 0)
    108. 

  108. 		return ret;
    109. 

  109. 	return (int)data;
    110. 

  110. }
    111. 

  111. 

  112. static int max8649_set_bits(struct i2c_client *i2c, int reg,
    113. 

  113. 			    unsigned char mask, unsigned char data)
    114. 

  114. {
    115. 

  115. 	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
    116. 

  116. 	unsigned char value;
    117. 

  117. 	int ret;
    118. 

  118. 

  119. 	mutex_lock(&info->io_lock);
    120. 

  120. 	ret = max8649_read_device(i2c, reg, 1, &value);
    121. 

  121. 	if (ret < 0)
    122. 

  122. 		goto out;
    123. 

  123. 	value &= ~mask;
    124. 

  124. 	value |= data;
    125. 

  125. 	ret = max8649_write_device(i2c, reg, 1, &value);
    126. 

  126. out:
    127. 

  127. 	mutex_unlock(&info->io_lock);
    128. 

  128. 	return ret;
    129. 

  129. }
    130. 

  130. 

  131. static inline int check_range(int min_uV, int max_uV)
    132. 

  132. {
    133. 

  133. 	if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
    134. 

  134. 		|| (min_uV > max_uV))
    135. 

  135. 		return -EINVAL;
    136. 

  136. 	return 0;
    137. 

  137. }
    138. 

  138. 

  139. static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
    140. 

  140. {
    141. 

  141. 	return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
    142. 

  142. }
    143. 

  143. 

  144. static int max8649_get_voltage(struct regulator_dev *rdev)
    145. 

  145. {
    146. 

  146. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    147. 

  147. 	unsigned char data;
    148. 

  148. 	int ret;
    149. 

  149. 

  150. 	ret = max8649_reg_read(info->i2c, info->vol_reg);
    151. 

  151. 	if (ret < 0)
    152. 

  152. 		return ret;
    153. 

  153. 	data = (unsigned char)ret & MAX8649_VOL_MASK;
    154. 

  154. 	return max8649_list_voltage(rdev, data);
    155. 

  155. }
    156. 

  156. 

  157. static int max8649_set_voltage(struct regulator_dev *rdev,
    158. 

  158. 			       int min_uV, int max_uV, unsigned *selector)
    159. 

  159. {
    160. 

  160. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    161. 

  161. 	unsigned char data, mask;
    162. 

  162. 

  163. 	if (check_range(min_uV, max_uV)) {
    164. 

  164. 		dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
    165. 

  165. 			min_uV, max_uV);
    166. 

  166. 		return -EINVAL;
    167. 

  167. 	}
    168. 

  168. 	data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
    169. 

  169. 		/ MAX8649_DCDC_STEP;
    170. 

  170. 	mask = MAX8649_VOL_MASK;
    171. 

  171. 	*selector = data & mask;
    172. 

  172. 

  173. 	return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
    174. 

  174. }
    175. 

  175. 

  176. /* EN_PD means pulldown on EN input */
    177. 

  177. static int max8649_enable(struct regulator_dev *rdev)
    178. 

  178. {
    179. 

  179. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    180. 

  180. 	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
    181. 

  181. }
    182. 

  182. 

  183. /*
    184. 

  184.  * Applied internal pulldown resistor on EN input pin.
    185. 

  185.  * If pulldown EN pin outside, it would be better.
    186. 

  186.  */
    187. 

  187. static int max8649_disable(struct regulator_dev *rdev)
    188. 

  188. {
    189. 

  189. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    190. 

  190. 	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
    191. 

  191. 				MAX8649_EN_PD);
    192. 

  192. }
    193. 

  193. 

  194. static int max8649_is_enabled(struct regulator_dev *rdev)
    195. 

  195. {
    196. 

  196. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    197. 

  197. 	int ret;
    198. 

  198. 

  199. 	ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
    200. 

  200. 	if (ret < 0)
    201. 

  201. 		return ret;
    202. 

  202. 	return !((unsigned char)ret & MAX8649_EN_PD);
    203. 

  203. }
    204. 

  204. 

  205. static int max8649_enable_time(struct regulator_dev *rdev)
    206. 

  206. {
    207. 

  207. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    208. 

  208. 	int voltage, rate, ret;
    209. 

  209. 

  210. 	/* get voltage */
    211. 

  211. 	ret = max8649_reg_read(info->i2c, info->vol_reg);
    212. 

  212. 	if (ret < 0)
    213. 

  213. 		return ret;
    214. 

  214. 	ret &= MAX8649_VOL_MASK;
    215. 

  215. 	voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */
    216. 

  216. 

  217. 	/* get rate */
    218. 

  218. 	ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
    219. 

  219. 	if (ret < 0)
    220. 

  220. 		return ret;
    221. 

  221. 	ret = (ret & MAX8649_RAMP_MASK) >> 5;
    222. 

  222. 	rate = (32 * 1000) >> ret;	/* uV/uS */
    223. 

  223. 

  224. 	return (voltage / rate);
    225. 

  225. }
    226. 

  226. 

  227. static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
    228. 

  228. {
    229. 

  229. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    230. 

  230. 

  231. 	switch (mode) {
    232. 

  232. 	case REGULATOR_MODE_FAST:
    233. 

  233. 		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
    234. 

  234. 				 MAX8649_FORCE_PWM);
    235. 

  235. 		break;
    236. 

  236. 	case REGULATOR_MODE_NORMAL:
    237. 

  237. 		max8649_set_bits(info->i2c, info->vol_reg,
    238. 

  238. 				 MAX8649_FORCE_PWM, 0);
    239. 

  239. 		break;
    240. 

  240. 	default:
    241. 

  241. 		return -EINVAL;
    242. 

  242. 	}
    243. 

  243. 	return 0;
    244. 

  244. }
    245. 

  245. 

  246. static unsigned int max8649_get_mode(struct regulator_dev *rdev)
    247. 

  247. {
    248. 

  248. 	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
    249. 

  249. 	int ret;
    250. 

  250. 

  251. 	ret = max8649_reg_read(info->i2c, info->vol_reg);
    252. 

  252. 	if (ret & MAX8649_FORCE_PWM)
    253. 

  253. 		return REGULATOR_MODE_FAST;
    254. 

  254. 	return REGULATOR_MODE_NORMAL;
    255. 

  255. }
    256. 

  256. 

  257. static struct regulator_ops max8649_dcdc_ops = {
    258. 

  258. 	.set_voltage	= max8649_set_voltage,
    259. 

  259. 	.get_voltage	= max8649_get_voltage,
    260. 

  260. 	.list_voltage	= max8649_list_voltage,
    261. 

  261. 	.enable		= max8649_enable,
    262. 

  262. 	.disable	= max8649_disable,
    263. 

  263. 	.is_enabled	= max8649_is_enabled,
    264. 

  264. 	.enable_time	= max8649_enable_time,
    265. 

  265. 	.set_mode	= max8649_set_mode,
    266. 

  266. 	.get_mode	= max8649_get_mode,
    267. 

  267. 

  268. };
    269. 

  269. 

  270. static struct regulator_desc dcdc_desc = {
    271. 

  271. 	.name		= "max8649",
    272. 

  272. 	.ops		= &max8649_dcdc_ops,
    273. 

  273. 	.type		= REGULATOR_VOLTAGE,
    274. 

  274. 	.n_voltages	= 1 << 6,
    275. 

  275. 	.owner		= THIS_MODULE,
    276. 

  276. };
    277. 

  277. 

  278. static int __devinit max8649_regulator_probe(struct i2c_client *client,
    279. 

  279. 					     const struct i2c_device_id *id)
    280. 

  280. {
    281. 

  281. 	struct max8649_platform_data *pdata = client->dev.platform_data;
    282. 

  282. 	struct max8649_regulator_info *info = NULL;
    283. 

  283. 	unsigned char data;
    284. 

  284. 	int ret;
    285. 

  285. 

  286. 	info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
    287. 

  287. 	if (!info) {
    288. 

  288. 		dev_err(&client->dev, "No enough memory\n");
    289. 

  289. 		return -ENOMEM;
    290. 

  290. 	}
    291. 

  291. 

  292. 	info->i2c = client;
    293. 

  293. 	info->dev = &client->dev;
    294. 

  294. 	mutex_init(&info->io_lock);
    295. 

  295. 	i2c_set_clientdata(client, info);
    296. 

  296. 

  297. 	info->mode = pdata->mode;
    298. 

  298. 	switch (info->mode) {
    299. 

  299. 	case 0:
    300. 

  300. 		info->vol_reg = MAX8649_MODE0;
    301. 

  301. 		break;
    302. 

  302. 	case 1:
    303. 

  303. 		info->vol_reg = MAX8649_MODE1;
    304. 

  304. 		break;
    305. 

  305. 	case 2:
    306. 

  306. 		info->vol_reg = MAX8649_MODE2;
    307. 

  307. 		break;
    308. 

  308. 	case 3:
    309. 

  309. 		info->vol_reg = MAX8649_MODE3;
    310. 

  310. 		break;
    311. 

  311. 	default:
    312. 

  312. 		break;
    313. 

  313. 	}
    314. 

  314. 

  315. 	ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
    316. 

  316. 	if (ret < 0) {
    317. 

  317. 		dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
    318. 

  318. 			ret);
    319. 

  319. 		goto out;
    320. 

  320. 	}
    321. 

  321. 	dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
    322. 

  322. 

  323. 	/* enable VID0 & VID1 */
    324. 

  324. 	max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
    325. 

  325. 

  326. 	/* enable/disable external clock synchronization */
    327. 

  327. 	info->extclk = pdata->extclk;
    328. 

  328. 	data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
    329. 

  329. 	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
    330. 

  330. 	if (info->extclk) {
    331. 

  331. 		/* set external clock frequency */
    332. 

  332. 		info->extclk_freq = pdata->extclk_freq;
    333. 

  333. 		max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
    334. 

  334. 				 info->extclk_freq << 6);
    335. 

  335. 	}
    336. 

  336. 

  337. 	if (pdata->ramp_timing) {
    338. 

  338. 		info->ramp_timing = pdata->ramp_timing;
    339. 

  339. 		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
    340. 

  340. 				 info->ramp_timing << 5);
    341. 

  341. 	}
    342. 

  342. 

  343. 	info->ramp_down = pdata->ramp_down;
    344. 

  344. 	if (info->ramp_down) {
    345. 

  345. 		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
    346. 

  346. 				 MAX8649_RAMP_DOWN);
    347. 

  347. 	}
    348. 

  348. 

  349. 	info->regulator = regulator_register(&dcdc_desc, &client->dev,
    350. 

  350. 					     pdata->regulator, info);
    351. 

  351. 	if (IS_ERR(info->regulator)) {
    352. 

  352. 		dev_err(info->dev, "failed to register regulator %s\n",
    353. 

  353. 			dcdc_desc.name);
    354. 

  354. 		ret = PTR_ERR(info->regulator);
    355. 

  355. 		goto out;
    356. 

  356. 	}
    357. 

  357. 

  358. 	dev_info(info->dev, "Max8649 regulator device is detected.\n");
    359. 

  359. 	return 0;
    360. 

  360. out:
    361. 

  361. 	kfree(info);
    362. 

  362. 	return ret;
    363. 

  363. }
    364. 

  364. 

  365. static int __devexit max8649_regulator_remove(struct i2c_client *client)
    366. 

  366. {
    367. 

  367. 	struct max8649_regulator_info *info = i2c_get_clientdata(client);
    368. 

  368. 

  369. 	if (info) {
    370. 

  370. 		if (info->regulator)
    371. 

  371. 			regulator_unregister(info->regulator);
    372. 

  372. 		kfree(info);
    373. 

  373. 	}
    374. 

  374. 

  375. 	return 0;
    376. 

  376. }
    377. 

  377. 

  378. static const struct i2c_device_id max8649_id[] = {
    379. 

  379. 	{ "max8649", 0 },
    380. 

  380. 	{ }
    381. 

  381. };
    382. 

  382. MODULE_DEVICE_TABLE(i2c, max8649_id);
    383. 

  383. 

  384. static struct i2c_driver max8649_driver = {
    385. 

  385. 	.probe		= max8649_regulator_probe,
    386. 

  386. 	.remove		= __devexit_p(max8649_regulator_remove),
    387. 

  387. 	.driver		= {
    388. 

  388. 		.name	= "max8649",
    389. 

  389. 	},
    390. 

  390. 	.id_table	= max8649_id,
    391. 

  391. };
    392. 

  392. 

  393. static int __init max8649_init(void)
    394. 

  394. {
    395. 

  395. 	return i2c_add_driver(&max8649_driver);
    396. 

  396. }
    397. 

  397. subsys_initcall(max8649_init);
    398. 

  398. 

  399. static void __exit max8649_exit(void)
    400. 

  400. {
    401. 

  401. 	i2c_del_driver(&max8649_driver);
    402. 

  402. }
    403. 

  403. module_exit(max8649_exit);
    404. 

  404. 

  405. /* Module information */
    406. 

  406. MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
    407. 

  407. MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
    408. 

  408. MODULE_LICENSE("GPL");
    409.