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