ad1938.c 14 KB

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  1. /*
  2. * File: sound/soc/codecs/ad1938.c
  3. * Author: Barry Song <Barry.Song@analog.com>
  4. *
  5. * Created: June 04 2009
  6. * Description: Driver for AD1938 sound chip
  7. *
  8. * Modified:
  9. * Copyright 2009 Analog Devices Inc.
  10. *
  11. * Bugs: Enter bugs at http://blackfin.uclinux.org/
  12. *
  13. * This program is free software; you can redistribute it and/or modify
  14. * it under the terms of the GNU General Public License as published by
  15. * the Free Software Foundation; either version 2 of the License, or
  16. * (at your option) any later version.
  17. *
  18. * This program is distributed in the hope that it will be useful,
  19. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  21. * GNU General Public License for more details.
  22. *
  23. * You should have received a copy of the GNU General Public License
  24. * along with this program; if not, see the file COPYING, or write
  25. * to the Free Software Foundation, Inc.,
  26. * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  27. */
  28. #include <linux/init.h>
  29. #include <linux/slab.h>
  30. #include <linux/module.h>
  31. #include <linux/kernel.h>
  32. #include <linux/device.h>
  33. #include <sound/core.h>
  34. #include <sound/pcm.h>
  35. #include <sound/pcm_params.h>
  36. #include <sound/initval.h>
  37. #include <sound/soc.h>
  38. #include <sound/tlv.h>
  39. #include <sound/soc-dapm.h>
  40. #include <linux/spi/spi.h>
  41. #include "ad1938.h"
  42. /* codec private data */
  43. struct ad1938_priv {
  44. struct snd_soc_codec codec;
  45. u8 reg_cache[AD1938_NUM_REGS];
  46. };
  47. /* ad1938 register cache & default register settings */
  48. static const u8 ad1938_reg[AD1938_NUM_REGS] = {
  49. 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0, 0,
  50. };
  51. static struct snd_soc_codec *ad1938_codec;
  52. struct snd_soc_codec_device soc_codec_dev_ad1938;
  53. static int ad1938_register(struct ad1938_priv *ad1938);
  54. static void ad1938_unregister(struct ad1938_priv *ad1938);
  55. /*
  56. * AD1938 volume/mute/de-emphasis etc. controls
  57. */
  58. static const char *ad1938_deemp[] = {"None", "48kHz", "44.1kHz", "32kHz"};
  59. static const struct soc_enum ad1938_deemp_enum =
  60. SOC_ENUM_SINGLE(AD1938_DAC_CTRL2, 1, 4, ad1938_deemp);
  61. static const struct snd_kcontrol_new ad1938_snd_controls[] = {
  62. /* DAC volume control */
  63. SOC_DOUBLE_R("DAC1 Volume", AD1938_DAC_L1_VOL,
  64. AD1938_DAC_R1_VOL, 0, 0xFF, 1),
  65. SOC_DOUBLE_R("DAC2 Volume", AD1938_DAC_L2_VOL,
  66. AD1938_DAC_R2_VOL, 0, 0xFF, 1),
  67. SOC_DOUBLE_R("DAC3 Volume", AD1938_DAC_L3_VOL,
  68. AD1938_DAC_R3_VOL, 0, 0xFF, 1),
  69. SOC_DOUBLE_R("DAC4 Volume", AD1938_DAC_L4_VOL,
  70. AD1938_DAC_R4_VOL, 0, 0xFF, 1),
  71. /* ADC switch control */
  72. SOC_DOUBLE("ADC1 Switch", AD1938_ADC_CTRL0, AD1938_ADCL1_MUTE,
  73. AD1938_ADCR1_MUTE, 1, 1),
  74. SOC_DOUBLE("ADC2 Switch", AD1938_ADC_CTRL0, AD1938_ADCL2_MUTE,
  75. AD1938_ADCR2_MUTE, 1, 1),
  76. /* DAC switch control */
  77. SOC_DOUBLE("DAC1 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL1_MUTE,
  78. AD1938_DACR1_MUTE, 1, 1),
  79. SOC_DOUBLE("DAC2 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL2_MUTE,
  80. AD1938_DACR2_MUTE, 1, 1),
  81. SOC_DOUBLE("DAC3 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL3_MUTE,
  82. AD1938_DACR3_MUTE, 1, 1),
  83. SOC_DOUBLE("DAC4 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL4_MUTE,
  84. AD1938_DACR4_MUTE, 1, 1),
  85. /* ADC high-pass filter */
  86. SOC_SINGLE("ADC High Pass Filter Switch", AD1938_ADC_CTRL0,
  87. AD1938_ADC_HIGHPASS_FILTER, 1, 0),
  88. /* DAC de-emphasis */
  89. SOC_ENUM("Playback Deemphasis", ad1938_deemp_enum),
  90. };
  91. static const struct snd_soc_dapm_widget ad1938_dapm_widgets[] = {
  92. SND_SOC_DAPM_DAC("DAC", "Playback", AD1938_DAC_CTRL0, 0, 1),
  93. SND_SOC_DAPM_ADC("ADC", "Capture", SND_SOC_NOPM, 0, 0),
  94. SND_SOC_DAPM_SUPPLY("PLL_PWR", AD1938_PLL_CLK_CTRL0, 0, 1, NULL, 0),
  95. SND_SOC_DAPM_SUPPLY("ADC_PWR", AD1938_ADC_CTRL0, 0, 1, NULL, 0),
  96. SND_SOC_DAPM_OUTPUT("DAC1OUT"),
  97. SND_SOC_DAPM_OUTPUT("DAC2OUT"),
  98. SND_SOC_DAPM_OUTPUT("DAC3OUT"),
  99. SND_SOC_DAPM_OUTPUT("DAC4OUT"),
  100. SND_SOC_DAPM_INPUT("ADC1IN"),
  101. SND_SOC_DAPM_INPUT("ADC2IN"),
  102. };
  103. static const struct snd_soc_dapm_route audio_paths[] = {
  104. { "DAC", NULL, "PLL_PWR" },
  105. { "ADC", NULL, "PLL_PWR" },
  106. { "DAC", NULL, "ADC_PWR" },
  107. { "ADC", NULL, "ADC_PWR" },
  108. { "DAC1OUT", "DAC1 Switch", "DAC" },
  109. { "DAC2OUT", "DAC2 Switch", "DAC" },
  110. { "DAC3OUT", "DAC3 Switch", "DAC" },
  111. { "DAC4OUT", "DAC4 Switch", "DAC" },
  112. { "ADC", "ADC1 Switch", "ADC1IN" },
  113. { "ADC", "ADC2 Switch", "ADC2IN" },
  114. };
  115. /*
  116. * DAI ops entries
  117. */
  118. static int ad1938_mute(struct snd_soc_dai *dai, int mute)
  119. {
  120. struct snd_soc_codec *codec = dai->codec;
  121. int reg;
  122. reg = snd_soc_read(codec, AD1938_DAC_CTRL2);
  123. reg = (mute > 0) ? reg | AD1938_DAC_MASTER_MUTE : reg &
  124. (~AD1938_DAC_MASTER_MUTE);
  125. snd_soc_write(codec, AD1938_DAC_CTRL2, reg);
  126. return 0;
  127. }
  128. static int ad1938_set_tdm_slot(struct snd_soc_dai *dai, unsigned int tx_mask,
  129. unsigned int rx_mask, int slots, int width)
  130. {
  131. struct snd_soc_codec *codec = dai->codec;
  132. int dac_reg = snd_soc_read(codec, AD1938_DAC_CTRL1);
  133. int adc_reg = snd_soc_read(codec, AD1938_ADC_CTRL2);
  134. dac_reg &= ~AD1938_DAC_CHAN_MASK;
  135. adc_reg &= ~AD1938_ADC_CHAN_MASK;
  136. switch (slots) {
  137. case 2:
  138. dac_reg |= AD1938_DAC_2_CHANNELS << AD1938_DAC_CHAN_SHFT;
  139. adc_reg |= AD1938_ADC_2_CHANNELS << AD1938_ADC_CHAN_SHFT;
  140. break;
  141. case 4:
  142. dac_reg |= AD1938_DAC_4_CHANNELS << AD1938_DAC_CHAN_SHFT;
  143. adc_reg |= AD1938_ADC_4_CHANNELS << AD1938_ADC_CHAN_SHFT;
  144. break;
  145. case 8:
  146. dac_reg |= AD1938_DAC_8_CHANNELS << AD1938_DAC_CHAN_SHFT;
  147. adc_reg |= AD1938_ADC_8_CHANNELS << AD1938_ADC_CHAN_SHFT;
  148. break;
  149. case 16:
  150. dac_reg |= AD1938_DAC_16_CHANNELS << AD1938_DAC_CHAN_SHFT;
  151. adc_reg |= AD1938_ADC_16_CHANNELS << AD1938_ADC_CHAN_SHFT;
  152. break;
  153. default:
  154. return -EINVAL;
  155. }
  156. snd_soc_write(codec, AD1938_DAC_CTRL1, dac_reg);
  157. snd_soc_write(codec, AD1938_ADC_CTRL2, adc_reg);
  158. return 0;
  159. }
  160. static int ad1938_set_dai_fmt(struct snd_soc_dai *codec_dai,
  161. unsigned int fmt)
  162. {
  163. struct snd_soc_codec *codec = codec_dai->codec;
  164. int adc_reg, dac_reg;
  165. adc_reg = snd_soc_read(codec, AD1938_ADC_CTRL2);
  166. dac_reg = snd_soc_read(codec, AD1938_DAC_CTRL1);
  167. /* At present, the driver only support AUX ADC mode(SND_SOC_DAIFMT_I2S
  168. * with TDM) and ADC&DAC TDM mode(SND_SOC_DAIFMT_DSP_A)
  169. */
  170. switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
  171. case SND_SOC_DAIFMT_I2S:
  172. adc_reg &= ~AD1938_ADC_SERFMT_MASK;
  173. adc_reg |= AD1938_ADC_SERFMT_TDM;
  174. break;
  175. case SND_SOC_DAIFMT_DSP_A:
  176. adc_reg &= ~AD1938_ADC_SERFMT_MASK;
  177. adc_reg |= AD1938_ADC_SERFMT_AUX;
  178. break;
  179. default:
  180. return -EINVAL;
  181. }
  182. switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
  183. case SND_SOC_DAIFMT_NB_NF: /* normal bit clock + frame */
  184. adc_reg &= ~AD1938_ADC_LEFT_HIGH;
  185. adc_reg &= ~AD1938_ADC_BCLK_INV;
  186. dac_reg &= ~AD1938_DAC_LEFT_HIGH;
  187. dac_reg &= ~AD1938_DAC_BCLK_INV;
  188. break;
  189. case SND_SOC_DAIFMT_NB_IF: /* normal bclk + invert frm */
  190. adc_reg |= AD1938_ADC_LEFT_HIGH;
  191. adc_reg &= ~AD1938_ADC_BCLK_INV;
  192. dac_reg |= AD1938_DAC_LEFT_HIGH;
  193. dac_reg &= ~AD1938_DAC_BCLK_INV;
  194. break;
  195. case SND_SOC_DAIFMT_IB_NF: /* invert bclk + normal frm */
  196. adc_reg &= ~AD1938_ADC_LEFT_HIGH;
  197. adc_reg |= AD1938_ADC_BCLK_INV;
  198. dac_reg &= ~AD1938_DAC_LEFT_HIGH;
  199. dac_reg |= AD1938_DAC_BCLK_INV;
  200. break;
  201. case SND_SOC_DAIFMT_IB_IF: /* invert bclk + frm */
  202. adc_reg |= AD1938_ADC_LEFT_HIGH;
  203. adc_reg |= AD1938_ADC_BCLK_INV;
  204. dac_reg |= AD1938_DAC_LEFT_HIGH;
  205. dac_reg |= AD1938_DAC_BCLK_INV;
  206. break;
  207. default:
  208. return -EINVAL;
  209. }
  210. switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
  211. case SND_SOC_DAIFMT_CBM_CFM: /* codec clk & frm master */
  212. adc_reg |= AD1938_ADC_LCR_MASTER;
  213. adc_reg |= AD1938_ADC_BCLK_MASTER;
  214. dac_reg |= AD1938_DAC_LCR_MASTER;
  215. dac_reg |= AD1938_DAC_BCLK_MASTER;
  216. break;
  217. case SND_SOC_DAIFMT_CBS_CFM: /* codec clk slave & frm master */
  218. adc_reg |= AD1938_ADC_LCR_MASTER;
  219. adc_reg &= ~AD1938_ADC_BCLK_MASTER;
  220. dac_reg |= AD1938_DAC_LCR_MASTER;
  221. dac_reg &= ~AD1938_DAC_BCLK_MASTER;
  222. break;
  223. case SND_SOC_DAIFMT_CBM_CFS: /* codec clk master & frame slave */
  224. adc_reg &= ~AD1938_ADC_LCR_MASTER;
  225. adc_reg |= AD1938_ADC_BCLK_MASTER;
  226. dac_reg &= ~AD1938_DAC_LCR_MASTER;
  227. dac_reg |= AD1938_DAC_BCLK_MASTER;
  228. break;
  229. case SND_SOC_DAIFMT_CBS_CFS: /* codec clk & frm slave */
  230. adc_reg &= ~AD1938_ADC_LCR_MASTER;
  231. adc_reg &= ~AD1938_ADC_BCLK_MASTER;
  232. dac_reg &= ~AD1938_DAC_LCR_MASTER;
  233. dac_reg &= ~AD1938_DAC_BCLK_MASTER;
  234. break;
  235. default:
  236. return -EINVAL;
  237. }
  238. snd_soc_write(codec, AD1938_ADC_CTRL2, adc_reg);
  239. snd_soc_write(codec, AD1938_DAC_CTRL1, dac_reg);
  240. return 0;
  241. }
  242. static int ad1938_hw_params(struct snd_pcm_substream *substream,
  243. struct snd_pcm_hw_params *params,
  244. struct snd_soc_dai *dai)
  245. {
  246. int word_len = 0, reg = 0;
  247. struct snd_soc_pcm_runtime *rtd = substream->private_data;
  248. struct snd_soc_device *socdev = rtd->socdev;
  249. struct snd_soc_codec *codec = socdev->card->codec;
  250. /* bit size */
  251. switch (params_format(params)) {
  252. case SNDRV_PCM_FORMAT_S16_LE:
  253. word_len = 3;
  254. break;
  255. case SNDRV_PCM_FORMAT_S20_3LE:
  256. word_len = 1;
  257. break;
  258. case SNDRV_PCM_FORMAT_S24_LE:
  259. case SNDRV_PCM_FORMAT_S32_LE:
  260. word_len = 0;
  261. break;
  262. }
  263. reg = snd_soc_read(codec, AD1938_DAC_CTRL2);
  264. reg = (reg & (~AD1938_DAC_WORD_LEN_MASK)) | word_len;
  265. snd_soc_write(codec, AD1938_DAC_CTRL2, reg);
  266. reg = snd_soc_read(codec, AD1938_ADC_CTRL1);
  267. reg = (reg & (~AD1938_ADC_WORD_LEN_MASK)) | word_len;
  268. snd_soc_write(codec, AD1938_ADC_CTRL1, reg);
  269. return 0;
  270. }
  271. static int __devinit ad1938_spi_probe(struct spi_device *spi)
  272. {
  273. struct snd_soc_codec *codec;
  274. struct ad1938_priv *ad1938;
  275. ad1938 = kzalloc(sizeof(struct ad1938_priv), GFP_KERNEL);
  276. if (ad1938 == NULL)
  277. return -ENOMEM;
  278. codec = &ad1938->codec;
  279. codec->control_data = spi;
  280. codec->dev = &spi->dev;
  281. dev_set_drvdata(&spi->dev, ad1938);
  282. return ad1938_register(ad1938);
  283. }
  284. static int __devexit ad1938_spi_remove(struct spi_device *spi)
  285. {
  286. struct ad1938_priv *ad1938 = dev_get_drvdata(&spi->dev);
  287. ad1938_unregister(ad1938);
  288. return 0;
  289. }
  290. static struct spi_driver ad1938_spi_driver = {
  291. .driver = {
  292. .name = "ad1938",
  293. .owner = THIS_MODULE,
  294. },
  295. .probe = ad1938_spi_probe,
  296. .remove = __devexit_p(ad1938_spi_remove),
  297. };
  298. static struct snd_soc_dai_ops ad1938_dai_ops = {
  299. .hw_params = ad1938_hw_params,
  300. .digital_mute = ad1938_mute,
  301. .set_tdm_slot = ad1938_set_tdm_slot,
  302. .set_fmt = ad1938_set_dai_fmt,
  303. };
  304. /* codec DAI instance */
  305. struct snd_soc_dai ad1938_dai = {
  306. .name = "AD1938",
  307. .playback = {
  308. .stream_name = "Playback",
  309. .channels_min = 2,
  310. .channels_max = 8,
  311. .rates = SNDRV_PCM_RATE_48000,
  312. .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE |
  313. SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE,
  314. },
  315. .capture = {
  316. .stream_name = "Capture",
  317. .channels_min = 2,
  318. .channels_max = 4,
  319. .rates = SNDRV_PCM_RATE_48000,
  320. .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE |
  321. SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE,
  322. },
  323. .ops = &ad1938_dai_ops,
  324. };
  325. EXPORT_SYMBOL_GPL(ad1938_dai);
  326. static int ad1938_register(struct ad1938_priv *ad1938)
  327. {
  328. int ret;
  329. struct snd_soc_codec *codec = &ad1938->codec;
  330. if (ad1938_codec) {
  331. dev_err(codec->dev, "Another ad1938 is registered\n");
  332. return -EINVAL;
  333. }
  334. mutex_init(&codec->mutex);
  335. INIT_LIST_HEAD(&codec->dapm_widgets);
  336. INIT_LIST_HEAD(&codec->dapm_paths);
  337. codec->private_data = ad1938;
  338. codec->reg_cache = ad1938->reg_cache;
  339. codec->reg_cache_size = AD1938_NUM_REGS;
  340. codec->name = "AD1938";
  341. codec->owner = THIS_MODULE;
  342. codec->dai = &ad1938_dai;
  343. codec->num_dai = 1;
  344. INIT_LIST_HEAD(&codec->dapm_widgets);
  345. INIT_LIST_HEAD(&codec->dapm_paths);
  346. ad1938_dai.dev = codec->dev;
  347. ad1938_codec = codec;
  348. memcpy(codec->reg_cache, ad1938_reg, AD1938_NUM_REGS);
  349. ret = snd_soc_codec_set_cache_io(codec, 16, 8, SND_SOC_SPI);
  350. if (ret < 0) {
  351. dev_err(codec->dev, "failed to set cache I/O: %d\n",
  352. ret);
  353. kfree(ad1938);
  354. return ret;
  355. }
  356. /* default setting for ad1938 */
  357. /* unmute dac channels */
  358. snd_soc_write(codec, AD1938_DAC_CHNL_MUTE, 0x0);
  359. /* de-emphasis: 48kHz, powedown dac */
  360. snd_soc_write(codec, AD1938_DAC_CTRL2, 0x1A);
  361. /* powerdown dac, dac in tdm mode */
  362. snd_soc_write(codec, AD1938_DAC_CTRL0, 0x41);
  363. /* high-pass filter enable */
  364. snd_soc_write(codec, AD1938_ADC_CTRL0, 0x3);
  365. /* sata delay=1, adc aux mode */
  366. snd_soc_write(codec, AD1938_ADC_CTRL1, 0x43);
  367. /* pll input: mclki/xi */
  368. snd_soc_write(codec, AD1938_PLL_CLK_CTRL0, 0x9D);
  369. snd_soc_write(codec, AD1938_PLL_CLK_CTRL1, 0x04);
  370. ret = snd_soc_register_codec(codec);
  371. if (ret != 0) {
  372. dev_err(codec->dev, "Failed to register codec: %d\n", ret);
  373. kfree(ad1938);
  374. return ret;
  375. }
  376. ret = snd_soc_register_dai(&ad1938_dai);
  377. if (ret != 0) {
  378. dev_err(codec->dev, "Failed to register DAI: %d\n", ret);
  379. snd_soc_unregister_codec(codec);
  380. kfree(ad1938);
  381. return ret;
  382. }
  383. return 0;
  384. }
  385. static void ad1938_unregister(struct ad1938_priv *ad1938)
  386. {
  387. snd_soc_unregister_dai(&ad1938_dai);
  388. snd_soc_unregister_codec(&ad1938->codec);
  389. kfree(ad1938);
  390. ad1938_codec = NULL;
  391. }
  392. static int ad1938_probe(struct platform_device *pdev)
  393. {
  394. struct snd_soc_device *socdev = platform_get_drvdata(pdev);
  395. struct snd_soc_codec *codec;
  396. int ret = 0;
  397. if (ad1938_codec == NULL) {
  398. dev_err(&pdev->dev, "Codec device not registered\n");
  399. return -ENODEV;
  400. }
  401. socdev->card->codec = ad1938_codec;
  402. codec = ad1938_codec;
  403. /* register pcms */
  404. ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
  405. if (ret < 0) {
  406. dev_err(codec->dev, "failed to create pcms: %d\n", ret);
  407. goto pcm_err;
  408. }
  409. snd_soc_add_controls(codec, ad1938_snd_controls,
  410. ARRAY_SIZE(ad1938_snd_controls));
  411. snd_soc_dapm_new_controls(codec, ad1938_dapm_widgets,
  412. ARRAY_SIZE(ad1938_dapm_widgets));
  413. snd_soc_dapm_add_routes(codec, audio_paths, ARRAY_SIZE(audio_paths));
  414. pcm_err:
  415. return ret;
  416. }
  417. /* power down chip */
  418. static int ad1938_remove(struct platform_device *pdev)
  419. {
  420. struct snd_soc_device *socdev = platform_get_drvdata(pdev);
  421. snd_soc_free_pcms(socdev);
  422. snd_soc_dapm_free(socdev);
  423. return 0;
  424. }
  425. struct snd_soc_codec_device soc_codec_dev_ad1938 = {
  426. .probe = ad1938_probe,
  427. .remove = ad1938_remove,
  428. };
  429. EXPORT_SYMBOL_GPL(soc_codec_dev_ad1938);
  430. static int __init ad1938_init(void)
  431. {
  432. int ret;
  433. ret = spi_register_driver(&ad1938_spi_driver);
  434. if (ret != 0) {
  435. printk(KERN_ERR "Failed to register ad1938 SPI driver: %d\n",
  436. ret);
  437. }
  438. return ret;
  439. }
  440. module_init(ad1938_init);
  441. static void __exit ad1938_exit(void)
  442. {
  443. spi_unregister_driver(&ad1938_spi_driver);
  444. }
  445. module_exit(ad1938_exit);
  446. MODULE_DESCRIPTION("ASoC ad1938 driver");
  447. MODULE_AUTHOR("Barry Song ");
  448. MODULE_LICENSE("GPL");