/drivers/rtc/rtc-max8998.c

https://bitbucket.org/cyanogenmod/android_kernel_asus_tf300t · C · 345 lines · 266 code · 65 blank · 14 comment · 21 complexity · 1be3ef123ed33db1ae6a8a13662f3c65 MD5 · raw file 

    

  1. /*
    2. 

  2.  * RTC driver for Maxim MAX8998
    3. 

  3.  *
    4. 

  4.  * Copyright (C) 2010 Samsung Electronics Co.Ltd
    5. 

  5.  * Author: Minkyu Kang <mk7.kang@samsung.com>
    6. 

  6.  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
    7. 

  7.  *
    8. 

  8.  *  This program is free software; you can redistribute  it and/or modify it
    9. 

  9.  *  under  the terms of  the GNU General  Public License as published by the
    10. 

  10.  *  Free Software Foundation;  either version 2 of the  License, or (at your
    11. 

  11.  *  option) any later version.
    12. 

  12.  *
    13. 

  13.  */
    14. 

  14. 

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

  16. #include <linux/i2c.h>
    17. 

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

  18. #include <linux/bcd.h>
    19. 

  19. #include <linux/rtc.h>
    20. 

  20. #include <linux/platform_device.h>
    21. 

  21. #include <linux/mfd/max8998.h>
    22. 

  22. #include <linux/mfd/max8998-private.h>
    23. 

  23. #include <linux/delay.h>
    24. 

  24. 

  25. #define MAX8998_RTC_SEC			0x00
    26. 

  26. #define MAX8998_RTC_MIN			0x01
    27. 

  27. #define MAX8998_RTC_HOUR		0x02
    28. 

  28. #define MAX8998_RTC_WEEKDAY		0x03
    29. 

  29. #define MAX8998_RTC_DATE		0x04
    30. 

  30. #define MAX8998_RTC_MONTH		0x05
    31. 

  31. #define MAX8998_RTC_YEAR1		0x06
    32. 

  32. #define MAX8998_RTC_YEAR2		0x07
    33. 

  33. #define MAX8998_ALARM0_SEC		0x08
    34. 

  34. #define MAX8998_ALARM0_MIN		0x09
    35. 

  35. #define MAX8998_ALARM0_HOUR		0x0a
    36. 

  36. #define MAX8998_ALARM0_WEEKDAY		0x0b
    37. 

  37. #define MAX8998_ALARM0_DATE		0x0c
    38. 

  38. #define MAX8998_ALARM0_MONTH		0x0d
    39. 

  39. #define MAX8998_ALARM0_YEAR1		0x0e
    40. 

  40. #define MAX8998_ALARM0_YEAR2		0x0f
    41. 

  41. #define MAX8998_ALARM1_SEC		0x10
    42. 

  42. #define MAX8998_ALARM1_MIN		0x11
    43. 

  43. #define MAX8998_ALARM1_HOUR		0x12
    44. 

  44. #define MAX8998_ALARM1_WEEKDAY		0x13
    45. 

  45. #define MAX8998_ALARM1_DATE		0x14
    46. 

  46. #define MAX8998_ALARM1_MONTH		0x15
    47. 

  47. #define MAX8998_ALARM1_YEAR1		0x16
    48. 

  48. #define MAX8998_ALARM1_YEAR2		0x17
    49. 

  49. #define MAX8998_ALARM0_CONF		0x18
    50. 

  50. #define MAX8998_ALARM1_CONF		0x19
    51. 

  51. #define MAX8998_RTC_STATUS		0x1a
    52. 

  52. #define MAX8998_WTSR_SMPL_CNTL		0x1b
    53. 

  53. #define MAX8998_TEST			0x1f
    54. 

  54. 

  55. #define HOUR_12				(1 << 7)
    56. 

  56. #define HOUR_PM				(1 << 5)
    57. 

  57. #define ALARM0_STATUS			(1 << 1)
    58. 

  58. #define ALARM1_STATUS			(1 << 2)
    59. 

  59. 

  60. enum {
    61. 

  61. 	RTC_SEC = 0,
    62. 

  62. 	RTC_MIN,
    63. 

  63. 	RTC_HOUR,
    64. 

  64. 	RTC_WEEKDAY,
    65. 

  65. 	RTC_DATE,
    66. 

  66. 	RTC_MONTH,
    67. 

  67. 	RTC_YEAR1,
    68. 

  68. 	RTC_YEAR2,
    69. 

  69. };
    70. 

  70. 

  71. struct max8998_rtc_info {
    72. 

  72. 	struct device		*dev;
    73. 

  73. 	struct max8998_dev	*max8998;
    74. 

  74. 	struct i2c_client	*rtc;
    75. 

  75. 	struct rtc_device	*rtc_dev;
    76. 

  76. 	int irq;
    77. 

  77. 	bool lp3974_bug_workaround;
    78. 

  78. };
    79. 

  79. 

  80. static void max8998_data_to_tm(u8 *data, struct rtc_time *tm)
    81. 

  81. {
    82. 

  82. 	tm->tm_sec = bcd2bin(data[RTC_SEC]);
    83. 

  83. 	tm->tm_min = bcd2bin(data[RTC_MIN]);
    84. 

  84. 	if (data[RTC_HOUR] & HOUR_12) {
    85. 

  85. 		tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x1f);
    86. 

  86. 		if (data[RTC_HOUR] & HOUR_PM)
    87. 

  87. 			tm->tm_hour += 12;
    88. 

  88. 	} else
    89. 

  89. 		tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x3f);
    90. 

  90. 

  91. 	tm->tm_wday = data[RTC_WEEKDAY] & 0x07;
    92. 

  92. 	tm->tm_mday = bcd2bin(data[RTC_DATE]);
    93. 

  93. 	tm->tm_mon = bcd2bin(data[RTC_MONTH]);
    94. 

  94. 	tm->tm_year = bcd2bin(data[RTC_YEAR1]) + bcd2bin(data[RTC_YEAR2]) * 100;
    95. 

  95. 	tm->tm_year -= 1900;
    96. 

  96. }
    97. 

  97. 

  98. static void max8998_tm_to_data(struct rtc_time *tm, u8 *data)
    99. 

  99. {
    100. 

  100. 	data[RTC_SEC] = bin2bcd(tm->tm_sec);
    101. 

  101. 	data[RTC_MIN] = bin2bcd(tm->tm_min);
    102. 

  102. 	data[RTC_HOUR] = bin2bcd(tm->tm_hour);
    103. 

  103. 	data[RTC_WEEKDAY] = tm->tm_wday;
    104. 

  104. 	data[RTC_DATE] = bin2bcd(tm->tm_mday);
    105. 

  105. 	data[RTC_MONTH] = bin2bcd(tm->tm_mon);
    106. 

  106. 	data[RTC_YEAR1] = bin2bcd(tm->tm_year % 100);
    107. 

  107. 	data[RTC_YEAR2] = bin2bcd((tm->tm_year + 1900) / 100);
    108. 

  108. }
    109. 

  109. 

  110. static int max8998_rtc_read_time(struct device *dev, struct rtc_time *tm)
    111. 

  111. {
    112. 

  112. 	struct max8998_rtc_info *info = dev_get_drvdata(dev);
    113. 

  113. 	u8 data[8];
    114. 

  114. 	int ret;
    115. 

  115. 

  116. 	ret = max8998_bulk_read(info->rtc, MAX8998_RTC_SEC, 8, data);
    117. 

  117. 	if (ret < 0)
    118. 

  118. 		return ret;
    119. 

  119. 

  120. 	max8998_data_to_tm(data, tm);
    121. 

  121. 

  122. 	return rtc_valid_tm(tm);
    123. 

  123. }
    124. 

  124. 

  125. static int max8998_rtc_set_time(struct device *dev, struct rtc_time *tm)
    126. 

  126. {
    127. 

  127. 	struct max8998_rtc_info *info = dev_get_drvdata(dev);
    128. 

  128. 	u8 data[8];
    129. 

  129. 	int ret;
    130. 

  130. 

  131. 	max8998_tm_to_data(tm, data);
    132. 

  132. 

  133. 	ret = max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data);
    134. 

  134. 

  135. 	if (info->lp3974_bug_workaround)
    136. 

  136. 		msleep(2000);
    137. 

  137. 

  138. 	return ret;
    139. 

  139. }
    140. 

  140. 

  141. static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    142. 

  142. {
    143. 

  143. 	struct max8998_rtc_info *info = dev_get_drvdata(dev);
    144. 

  144. 	u8 data[8];
    145. 

  145. 	u8 val;
    146. 

  146. 	int ret;
    147. 

  147. 

  148. 	ret = max8998_bulk_read(info->rtc, MAX8998_ALARM0_SEC, 8, data);
    149. 

  149. 	if (ret < 0)
    150. 

  150. 		return ret;
    151. 

  151. 

  152. 	max8998_data_to_tm(data, &alrm->time);
    153. 

  153. 

  154. 	ret = max8998_read_reg(info->rtc, MAX8998_ALARM0_CONF, &val);
    155. 

  155. 	if (ret < 0)
    156. 

  156. 		return ret;
    157. 

  157. 

  158. 	alrm->enabled = !!val;
    159. 

  159. 

  160. 	ret = max8998_read_reg(info->rtc, MAX8998_RTC_STATUS, &val);
    161. 

  161. 	if (ret < 0)
    162. 

  162. 		return ret;
    163. 

  163. 

  164. 	if (val & ALARM0_STATUS)
    165. 

  165. 		alrm->pending = 1;
    166. 

  166. 	else
    167. 

  167. 		alrm->pending = 0;
    168. 

  168. 

  169. 	return 0;
    170. 

  170. }
    171. 

  171. 

  172. static int max8998_rtc_stop_alarm(struct max8998_rtc_info *info)
    173. 

  173. {
    174. 

  174. 	int ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0);
    175. 

  175. 

  176. 	if (info->lp3974_bug_workaround)
    177. 

  177. 		msleep(2000);
    178. 

  178. 

  179. 	return ret;
    180. 

  180. }
    181. 

  181. 

  182. static int max8998_rtc_start_alarm(struct max8998_rtc_info *info)
    183. 

  183. {
    184. 

  184. 	int ret;
    185. 

  185. 	u8 alarm0_conf = 0x77;
    186. 

  186. 

  187. 	/* LP3974 with delay bug chips has rtc alarm bugs with "MONTH" field */
    188. 

  188. 	if (info->lp3974_bug_workaround)
    189. 

  189. 		alarm0_conf = 0x57;
    190. 

  190. 

  191. 	ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, alarm0_conf);
    192. 

  192. 

  193. 	if (info->lp3974_bug_workaround)
    194. 

  194. 		msleep(2000);
    195. 

  195. 

  196. 	return ret;
    197. 

  197. }
    198. 

  198. 

  199. static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    200. 

  200. {
    201. 

  201. 	struct max8998_rtc_info *info = dev_get_drvdata(dev);
    202. 

  202. 	u8 data[8];
    203. 

  203. 	int ret;
    204. 

  204. 

  205. 	max8998_tm_to_data(&alrm->time, data);
    206. 

  206. 

  207. 	ret = max8998_rtc_stop_alarm(info);
    208. 

  208. 	if (ret < 0)
    209. 

  209. 		return ret;
    210. 

  210. 

  211. 	ret = max8998_bulk_write(info->rtc, MAX8998_ALARM0_SEC, 8, data);
    212. 

  212. 	if (ret < 0)
    213. 

  213. 		return ret;
    214. 

  214. 

  215. 	if (info->lp3974_bug_workaround)
    216. 

  216. 		msleep(2000);
    217. 

  217. 

  218. 	if (alrm->enabled)
    219. 

  219. 		ret = max8998_rtc_start_alarm(info);
    220. 

  220. 

  221. 	return ret;
    222. 

  222. }
    223. 

  223. 

  224. static int max8998_rtc_alarm_irq_enable(struct device *dev,
    225. 

  225. 					unsigned int enabled)
    226. 

  226. {
    227. 

  227. 	struct max8998_rtc_info *info = dev_get_drvdata(dev);
    228. 

  228. 

  229. 	if (enabled)
    230. 

  230. 		return max8998_rtc_start_alarm(info);
    231. 

  231. 	else
    232. 

  232. 		return max8998_rtc_stop_alarm(info);
    233. 

  233. }
    234. 

  234. 

  235. static irqreturn_t max8998_rtc_alarm_irq(int irq, void *data)
    236. 

  236. {
    237. 

  237. 	struct max8998_rtc_info *info = data;
    238. 

  238. 

  239. 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
    240. 

  240. 

  241. 	return IRQ_HANDLED;
    242. 

  242. }
    243. 

  243. 

  244. static const struct rtc_class_ops max8998_rtc_ops = {
    245. 

  245. 	.read_time = max8998_rtc_read_time,
    246. 

  246. 	.set_time = max8998_rtc_set_time,
    247. 

  247. 	.read_alarm = max8998_rtc_read_alarm,
    248. 

  248. 	.set_alarm = max8998_rtc_set_alarm,
    249. 

  249. 	.alarm_irq_enable = max8998_rtc_alarm_irq_enable,
    250. 

  250. };
    251. 

  251. 

  252. static int __devinit max8998_rtc_probe(struct platform_device *pdev)
    253. 

  253. {
    254. 

  254. 	struct max8998_dev *max8998 = dev_get_drvdata(pdev->dev.parent);
    255. 

  255. 	struct max8998_platform_data *pdata = dev_get_platdata(max8998->dev);
    256. 

  256. 	struct max8998_rtc_info *info;
    257. 

  257. 	int ret;
    258. 

  258. 

  259. 	info = kzalloc(sizeof(struct max8998_rtc_info), GFP_KERNEL);
    260. 

  260. 	if (!info)
    261. 

  261. 		return -ENOMEM;
    262. 

  262. 

  263. 	info->dev = &pdev->dev;
    264. 

  264. 	info->max8998 = max8998;
    265. 

  265. 	info->rtc = max8998->rtc;
    266. 

  266. 	info->irq = max8998->irq_base + MAX8998_IRQ_ALARM0;
    267. 

  267. 

  268. 	platform_set_drvdata(pdev, info);
    269. 

  269. 

  270. 	info->rtc_dev = rtc_device_register("max8998-rtc", &pdev->dev,
    271. 

  271. 			&max8998_rtc_ops, THIS_MODULE);
    272. 

  272. 

  273. 	if (IS_ERR(info->rtc_dev)) {
    274. 

  274. 		ret = PTR_ERR(info->rtc_dev);
    275. 

  275. 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
    276. 

  276. 		goto out_rtc;
    277. 

  277. 	}
    278. 

  278. 

  279. 	ret = request_threaded_irq(info->irq, NULL, max8998_rtc_alarm_irq, 0,
    280. 

  280. 			"rtc-alarm0", info);
    281. 

  281. 

  282. 	if (ret < 0)
    283. 

  283. 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
    284. 

  284. 			info->irq, ret);
    285. 

  285. 

  286. 	dev_info(&pdev->dev, "RTC CHIP NAME: %s\n", pdev->id_entry->name);
    287. 

  287. 	if (pdata->rtc_delay) {
    288. 

  288. 		info->lp3974_bug_workaround = true;
    289. 

  289. 		dev_warn(&pdev->dev, "LP3974 with RTC REGERR option."
    290. 

  290. 				" RTC updates will be extremely slow.\n");
    291. 

  291. 	}
    292. 

  292. 

  293. 	return 0;
    294. 

  294. 

  295. out_rtc:
    296. 

  296. 	platform_set_drvdata(pdev, NULL);
    297. 

  297. 	kfree(info);
    298. 

  298. 	return ret;
    299. 

  299. }
    300. 

  300. 

  301. static int __devexit max8998_rtc_remove(struct platform_device *pdev)
    302. 

  302. {
    303. 

  303. 	struct max8998_rtc_info *info = platform_get_drvdata(pdev);
    304. 

  304. 

  305. 	if (info) {
    306. 

  306. 		free_irq(info->irq, info);
    307. 

  307. 		rtc_device_unregister(info->rtc_dev);
    308. 

  308. 		kfree(info);
    309. 

  309. 	}
    310. 

  310. 

  311. 	return 0;
    312. 

  312. }
    313. 

  313. 

  314. static const struct platform_device_id max8998_rtc_id[] = {
    315. 

  315. 	{ "max8998-rtc", TYPE_MAX8998 },
    316. 

  316. 	{ "lp3974-rtc", TYPE_LP3974 },
    317. 

  317. 	{ }
    318. 

  318. };
    319. 

  319. 

  320. static struct platform_driver max8998_rtc_driver = {
    321. 

  321. 	.driver		= {
    322. 

  322. 		.name	= "max8998-rtc",
    323. 

  323. 		.owner	= THIS_MODULE,
    324. 

  324. 	},
    325. 

  325. 	.probe		= max8998_rtc_probe,
    326. 

  326. 	.remove		= __devexit_p(max8998_rtc_remove),
    327. 

  327. 	.id_table	= max8998_rtc_id,
    328. 

  328. };
    329. 

  329. 

  330. static int __init max8998_rtc_init(void)
    331. 

  331. {
    332. 

  332. 	return platform_driver_register(&max8998_rtc_driver);
    333. 

  333. }
    334. 

  334. module_init(max8998_rtc_init);
    335. 

  335. 

  336. static void __exit max8998_rtc_exit(void)
    337. 

  337. {
    338. 

  338. 	platform_driver_unregister(&max8998_rtc_driver);
    339. 

  339. }
    340. 

  340. module_exit(max8998_rtc_exit);
    341. 

  341. 

  342. MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>");
    343. 

  343. MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
    344. 

  344. MODULE_DESCRIPTION("Maxim MAX8998 RTC driver");
    345. 

  345. MODULE_LICENSE("GPL");
    346.