omap-mcpdm.c 14 KB

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  1. /*
  2. * omap-mcpdm.c -- OMAP ALSA SoC DAI driver using McPDM port
  3. *
  4. * Copyright (C) 2009 - 2011 Texas Instruments
  5. *
  6. * Author: Misael Lopez Cruz <misael.lopez@ti.com>
  7. * Contact: Jorge Eduardo Candelaria <x0107209@ti.com>
  8. * Margarita Olaya <magi.olaya@ti.com>
  9. * Peter Ujfalusi <peter.ujfalusi@ti.com>
  10. *
  11. * This program is free software; you can redistribute it and/or
  12. * modify it under the terms of the GNU General Public License
  13. * version 2 as published by the Free Software Foundation.
  14. *
  15. * This program is distributed in the hope that it will be useful, but
  16. * WITHOUT ANY WARRANTY; without even the implied warranty of
  17. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18. * General Public License for more details.
  19. *
  20. * You should have received a copy of the GNU General Public License
  21. * along with this program; if not, write to the Free Software
  22. * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  23. * 02110-1301 USA
  24. *
  25. */
  26. #include <linux/init.h>
  27. #include <linux/module.h>
  28. #include <linux/platform_device.h>
  29. #include <linux/interrupt.h>
  30. #include <linux/err.h>
  31. #include <linux/io.h>
  32. #include <linux/irq.h>
  33. #include <linux/slab.h>
  34. #include <linux/pm_runtime.h>
  35. #include <linux/of_device.h>
  36. #include <sound/core.h>
  37. #include <sound/pcm.h>
  38. #include <sound/pcm_params.h>
  39. #include <sound/soc.h>
  40. #include <sound/dmaengine_pcm.h>
  41. #include "omap-mcpdm.h"
  42. struct mcpdm_link_config {
  43. u32 link_mask; /* channel mask for the direction */
  44. u32 threshold; /* FIFO threshold */
  45. };
  46. struct omap_mcpdm {
  47. struct device *dev;
  48. unsigned long phys_base;
  49. void __iomem *io_base;
  50. int irq;
  51. struct mutex mutex;
  52. /* Playback/Capture configuration */
  53. struct mcpdm_link_config config[2];
  54. /* McPDM dn offsets for rx1, and 2 channels */
  55. u32 dn_rx_offset;
  56. /* McPDM needs to be restarted due to runtime reconfiguration */
  57. bool restart;
  58. struct snd_dmaengine_dai_dma_data dma_data[2];
  59. };
  60. /*
  61. * Stream DMA parameters
  62. */
  63. static inline void omap_mcpdm_write(struct omap_mcpdm *mcpdm, u16 reg, u32 val)
  64. {
  65. __raw_writel(val, mcpdm->io_base + reg);
  66. }
  67. static inline int omap_mcpdm_read(struct omap_mcpdm *mcpdm, u16 reg)
  68. {
  69. return __raw_readl(mcpdm->io_base + reg);
  70. }
  71. #ifdef DEBUG
  72. static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm)
  73. {
  74. dev_dbg(mcpdm->dev, "***********************\n");
  75. dev_dbg(mcpdm->dev, "IRQSTATUS_RAW: 0x%04x\n",
  76. omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS_RAW));
  77. dev_dbg(mcpdm->dev, "IRQSTATUS: 0x%04x\n",
  78. omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS));
  79. dev_dbg(mcpdm->dev, "IRQENABLE_SET: 0x%04x\n",
  80. omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_SET));
  81. dev_dbg(mcpdm->dev, "IRQENABLE_CLR: 0x%04x\n",
  82. omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_CLR));
  83. dev_dbg(mcpdm->dev, "IRQWAKE_EN: 0x%04x\n",
  84. omap_mcpdm_read(mcpdm, MCPDM_REG_IRQWAKE_EN));
  85. dev_dbg(mcpdm->dev, "DMAENABLE_SET: 0x%04x\n",
  86. omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_SET));
  87. dev_dbg(mcpdm->dev, "DMAENABLE_CLR: 0x%04x\n",
  88. omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_CLR));
  89. dev_dbg(mcpdm->dev, "DMAWAKEEN: 0x%04x\n",
  90. omap_mcpdm_read(mcpdm, MCPDM_REG_DMAWAKEEN));
  91. dev_dbg(mcpdm->dev, "CTRL: 0x%04x\n",
  92. omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL));
  93. dev_dbg(mcpdm->dev, "DN_DATA: 0x%04x\n",
  94. omap_mcpdm_read(mcpdm, MCPDM_REG_DN_DATA));
  95. dev_dbg(mcpdm->dev, "UP_DATA: 0x%04x\n",
  96. omap_mcpdm_read(mcpdm, MCPDM_REG_UP_DATA));
  97. dev_dbg(mcpdm->dev, "FIFO_CTRL_DN: 0x%04x\n",
  98. omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_DN));
  99. dev_dbg(mcpdm->dev, "FIFO_CTRL_UP: 0x%04x\n",
  100. omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_UP));
  101. dev_dbg(mcpdm->dev, "***********************\n");
  102. }
  103. #else
  104. static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm) {}
  105. #endif
  106. /*
  107. * Enables the transfer through the PDM interface to/from the Phoenix
  108. * codec by enabling the corresponding UP or DN channels.
  109. */
  110. static void omap_mcpdm_start(struct omap_mcpdm *mcpdm)
  111. {
  112. u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
  113. u32 link_mask = mcpdm->config[0].link_mask | mcpdm->config[1].link_mask;
  114. ctrl |= (MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
  115. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  116. ctrl |= link_mask;
  117. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  118. ctrl &= ~(MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
  119. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  120. }
  121. /*
  122. * Disables the transfer through the PDM interface to/from the Phoenix
  123. * codec by disabling the corresponding UP or DN channels.
  124. */
  125. static void omap_mcpdm_stop(struct omap_mcpdm *mcpdm)
  126. {
  127. u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
  128. u32 link_mask = MCPDM_PDM_DN_MASK | MCPDM_PDM_UP_MASK;
  129. ctrl |= (MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
  130. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  131. ctrl &= ~(link_mask);
  132. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  133. ctrl &= ~(MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
  134. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
  135. }
  136. /*
  137. * Is the physical McPDM interface active.
  138. */
  139. static inline int omap_mcpdm_active(struct omap_mcpdm *mcpdm)
  140. {
  141. return omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL) &
  142. (MCPDM_PDM_DN_MASK | MCPDM_PDM_UP_MASK);
  143. }
  144. /*
  145. * Configures McPDM uplink, and downlink for audio.
  146. * This function should be called before omap_mcpdm_start.
  147. */
  148. static void omap_mcpdm_open_streams(struct omap_mcpdm *mcpdm)
  149. {
  150. omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_SET,
  151. MCPDM_DN_IRQ_EMPTY | MCPDM_DN_IRQ_FULL |
  152. MCPDM_UP_IRQ_EMPTY | MCPDM_UP_IRQ_FULL);
  153. /* Enable DN RX1/2 offset cancellation feature, if configured */
  154. if (mcpdm->dn_rx_offset) {
  155. u32 dn_offset = mcpdm->dn_rx_offset;
  156. omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
  157. dn_offset |= (MCPDM_DN_OFST_RX1_EN | MCPDM_DN_OFST_RX2_EN);
  158. omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
  159. }
  160. omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_DN,
  161. mcpdm->config[SNDRV_PCM_STREAM_PLAYBACK].threshold);
  162. omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_UP,
  163. mcpdm->config[SNDRV_PCM_STREAM_CAPTURE].threshold);
  164. omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_SET,
  165. MCPDM_DMA_DN_ENABLE | MCPDM_DMA_UP_ENABLE);
  166. }
  167. /*
  168. * Cleans McPDM uplink, and downlink configuration.
  169. * This function should be called when the stream is closed.
  170. */
  171. static void omap_mcpdm_close_streams(struct omap_mcpdm *mcpdm)
  172. {
  173. /* Disable irq request generation for downlink */
  174. omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_CLR,
  175. MCPDM_DN_IRQ_EMPTY | MCPDM_DN_IRQ_FULL);
  176. /* Disable DMA request generation for downlink */
  177. omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_CLR, MCPDM_DMA_DN_ENABLE);
  178. /* Disable irq request generation for uplink */
  179. omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_CLR,
  180. MCPDM_UP_IRQ_EMPTY | MCPDM_UP_IRQ_FULL);
  181. /* Disable DMA request generation for uplink */
  182. omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_CLR, MCPDM_DMA_UP_ENABLE);
  183. /* Disable RX1/2 offset cancellation */
  184. if (mcpdm->dn_rx_offset)
  185. omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, 0);
  186. }
  187. static irqreturn_t omap_mcpdm_irq_handler(int irq, void *dev_id)
  188. {
  189. struct omap_mcpdm *mcpdm = dev_id;
  190. int irq_status;
  191. irq_status = omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS);
  192. /* Acknowledge irq event */
  193. omap_mcpdm_write(mcpdm, MCPDM_REG_IRQSTATUS, irq_status);
  194. if (irq_status & MCPDM_DN_IRQ_FULL)
  195. dev_dbg(mcpdm->dev, "DN (playback) FIFO Full\n");
  196. if (irq_status & MCPDM_DN_IRQ_EMPTY)
  197. dev_dbg(mcpdm->dev, "DN (playback) FIFO Empty\n");
  198. if (irq_status & MCPDM_DN_IRQ)
  199. dev_dbg(mcpdm->dev, "DN (playback) write request\n");
  200. if (irq_status & MCPDM_UP_IRQ_FULL)
  201. dev_dbg(mcpdm->dev, "UP (capture) FIFO Full\n");
  202. if (irq_status & MCPDM_UP_IRQ_EMPTY)
  203. dev_dbg(mcpdm->dev, "UP (capture) FIFO Empty\n");
  204. if (irq_status & MCPDM_UP_IRQ)
  205. dev_dbg(mcpdm->dev, "UP (capture) write request\n");
  206. return IRQ_HANDLED;
  207. }
  208. static int omap_mcpdm_dai_startup(struct snd_pcm_substream *substream,
  209. struct snd_soc_dai *dai)
  210. {
  211. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  212. mutex_lock(&mcpdm->mutex);
  213. if (!dai->active) {
  214. u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
  215. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl | MCPDM_WD_EN);
  216. omap_mcpdm_open_streams(mcpdm);
  217. }
  218. mutex_unlock(&mcpdm->mutex);
  219. snd_soc_dai_set_dma_data(dai, substream,
  220. &mcpdm->dma_data[substream->stream]);
  221. return 0;
  222. }
  223. static void omap_mcpdm_dai_shutdown(struct snd_pcm_substream *substream,
  224. struct snd_soc_dai *dai)
  225. {
  226. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  227. mutex_lock(&mcpdm->mutex);
  228. if (!dai->active) {
  229. if (omap_mcpdm_active(mcpdm)) {
  230. omap_mcpdm_stop(mcpdm);
  231. omap_mcpdm_close_streams(mcpdm);
  232. mcpdm->config[0].link_mask = 0;
  233. mcpdm->config[1].link_mask = 0;
  234. }
  235. }
  236. mutex_unlock(&mcpdm->mutex);
  237. }
  238. static int omap_mcpdm_dai_hw_params(struct snd_pcm_substream *substream,
  239. struct snd_pcm_hw_params *params,
  240. struct snd_soc_dai *dai)
  241. {
  242. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  243. int stream = substream->stream;
  244. struct snd_dmaengine_dai_dma_data *dma_data;
  245. u32 threshold;
  246. int channels;
  247. int link_mask = 0;
  248. channels = params_channels(params);
  249. switch (channels) {
  250. case 5:
  251. if (stream == SNDRV_PCM_STREAM_CAPTURE)
  252. /* up to 3 channels for capture */
  253. return -EINVAL;
  254. link_mask |= 1 << 4;
  255. case 4:
  256. if (stream == SNDRV_PCM_STREAM_CAPTURE)
  257. /* up to 3 channels for capture */
  258. return -EINVAL;
  259. link_mask |= 1 << 3;
  260. case 3:
  261. link_mask |= 1 << 2;
  262. case 2:
  263. link_mask |= 1 << 1;
  264. case 1:
  265. link_mask |= 1 << 0;
  266. break;
  267. default:
  268. /* unsupported number of channels */
  269. return -EINVAL;
  270. }
  271. dma_data = snd_soc_dai_get_dma_data(dai, substream);
  272. threshold = mcpdm->config[stream].threshold;
  273. /* Configure McPDM channels, and DMA packet size */
  274. if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
  275. link_mask <<= 3;
  276. /* If capture is not running assume a stereo stream to come */
  277. if (!mcpdm->config[!stream].link_mask)
  278. mcpdm->config[!stream].link_mask = 0x3;
  279. dma_data->maxburst =
  280. (MCPDM_DN_THRES_MAX - threshold) * channels;
  281. } else {
  282. /* If playback is not running assume a stereo stream to come */
  283. if (!mcpdm->config[!stream].link_mask)
  284. mcpdm->config[!stream].link_mask = (0x3 << 3);
  285. dma_data->maxburst = threshold * channels;
  286. }
  287. /* Check if we need to restart McPDM with this stream */
  288. if (mcpdm->config[stream].link_mask &&
  289. mcpdm->config[stream].link_mask != link_mask)
  290. mcpdm->restart = true;
  291. mcpdm->config[stream].link_mask = link_mask;
  292. return 0;
  293. }
  294. static int omap_mcpdm_prepare(struct snd_pcm_substream *substream,
  295. struct snd_soc_dai *dai)
  296. {
  297. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  298. if (!omap_mcpdm_active(mcpdm)) {
  299. omap_mcpdm_start(mcpdm);
  300. omap_mcpdm_reg_dump(mcpdm);
  301. } else if (mcpdm->restart) {
  302. omap_mcpdm_stop(mcpdm);
  303. omap_mcpdm_start(mcpdm);
  304. mcpdm->restart = false;
  305. omap_mcpdm_reg_dump(mcpdm);
  306. }
  307. return 0;
  308. }
  309. static const struct snd_soc_dai_ops omap_mcpdm_dai_ops = {
  310. .startup = omap_mcpdm_dai_startup,
  311. .shutdown = omap_mcpdm_dai_shutdown,
  312. .hw_params = omap_mcpdm_dai_hw_params,
  313. .prepare = omap_mcpdm_prepare,
  314. };
  315. static int omap_mcpdm_probe(struct snd_soc_dai *dai)
  316. {
  317. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  318. int ret;
  319. pm_runtime_enable(mcpdm->dev);
  320. /* Disable lines while request is ongoing */
  321. pm_runtime_get_sync(mcpdm->dev);
  322. omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, 0x00);
  323. ret = devm_request_irq(mcpdm->dev, mcpdm->irq, omap_mcpdm_irq_handler,
  324. 0, "McPDM", (void *)mcpdm);
  325. pm_runtime_put_sync(mcpdm->dev);
  326. if (ret) {
  327. dev_err(mcpdm->dev, "Request for IRQ failed\n");
  328. pm_runtime_disable(mcpdm->dev);
  329. }
  330. /* Configure McPDM threshold values */
  331. mcpdm->config[SNDRV_PCM_STREAM_PLAYBACK].threshold = 2;
  332. mcpdm->config[SNDRV_PCM_STREAM_CAPTURE].threshold =
  333. MCPDM_UP_THRES_MAX - 3;
  334. return ret;
  335. }
  336. static int omap_mcpdm_remove(struct snd_soc_dai *dai)
  337. {
  338. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
  339. pm_runtime_disable(mcpdm->dev);
  340. return 0;
  341. }
  342. #define OMAP_MCPDM_RATES (SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000)
  343. #define OMAP_MCPDM_FORMATS SNDRV_PCM_FMTBIT_S32_LE
  344. static struct snd_soc_dai_driver omap_mcpdm_dai = {
  345. .probe = omap_mcpdm_probe,
  346. .remove = omap_mcpdm_remove,
  347. .probe_order = SND_SOC_COMP_ORDER_LATE,
  348. .remove_order = SND_SOC_COMP_ORDER_EARLY,
  349. .playback = {
  350. .channels_min = 1,
  351. .channels_max = 5,
  352. .rates = OMAP_MCPDM_RATES,
  353. .formats = OMAP_MCPDM_FORMATS,
  354. .sig_bits = 24,
  355. },
  356. .capture = {
  357. .channels_min = 1,
  358. .channels_max = 3,
  359. .rates = OMAP_MCPDM_RATES,
  360. .formats = OMAP_MCPDM_FORMATS,
  361. .sig_bits = 24,
  362. },
  363. .ops = &omap_mcpdm_dai_ops,
  364. };
  365. static const struct snd_soc_component_driver omap_mcpdm_component = {
  366. .name = "omap-mcpdm",
  367. };
  368. void omap_mcpdm_configure_dn_offsets(struct snd_soc_pcm_runtime *rtd,
  369. u8 rx1, u8 rx2)
  370. {
  371. struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(rtd->cpu_dai);
  372. mcpdm->dn_rx_offset = MCPDM_DNOFST_RX1(rx1) | MCPDM_DNOFST_RX2(rx2);
  373. }
  374. EXPORT_SYMBOL_GPL(omap_mcpdm_configure_dn_offsets);
  375. static int asoc_mcpdm_probe(struct platform_device *pdev)
  376. {
  377. struct omap_mcpdm *mcpdm;
  378. struct resource *res;
  379. mcpdm = devm_kzalloc(&pdev->dev, sizeof(struct omap_mcpdm), GFP_KERNEL);
  380. if (!mcpdm)
  381. return -ENOMEM;
  382. platform_set_drvdata(pdev, mcpdm);
  383. mutex_init(&mcpdm->mutex);
  384. res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma");
  385. if (res == NULL)
  386. return -ENOMEM;
  387. mcpdm->dma_data[0].addr = res->start + MCPDM_REG_DN_DATA;
  388. mcpdm->dma_data[1].addr = res->start + MCPDM_REG_UP_DATA;
  389. mcpdm->dma_data[0].filter_data = "dn_link";
  390. mcpdm->dma_data[1].filter_data = "up_link";
  391. res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mpu");
  392. mcpdm->io_base = devm_ioremap_resource(&pdev->dev, res);
  393. if (IS_ERR(mcpdm->io_base))
  394. return PTR_ERR(mcpdm->io_base);
  395. mcpdm->irq = platform_get_irq(pdev, 0);
  396. if (mcpdm->irq < 0)
  397. return mcpdm->irq;
  398. mcpdm->dev = &pdev->dev;
  399. return snd_soc_register_component(&pdev->dev, &omap_mcpdm_component,
  400. &omap_mcpdm_dai, 1);
  401. }
  402. static int asoc_mcpdm_remove(struct platform_device *pdev)
  403. {
  404. snd_soc_unregister_component(&pdev->dev);
  405. return 0;
  406. }
  407. static const struct of_device_id omap_mcpdm_of_match[] = {
  408. { .compatible = "ti,omap4-mcpdm", },
  409. { }
  410. };
  411. MODULE_DEVICE_TABLE(of, omap_mcpdm_of_match);
  412. static struct platform_driver asoc_mcpdm_driver = {
  413. .driver = {
  414. .name = "omap-mcpdm",
  415. .owner = THIS_MODULE,
  416. .of_match_table = omap_mcpdm_of_match,
  417. },
  418. .probe = asoc_mcpdm_probe,
  419. .remove = asoc_mcpdm_remove,
  420. };
  421. module_platform_driver(asoc_mcpdm_driver);
  422. MODULE_ALIAS("platform:omap-mcpdm");
  423. MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@ti.com>");
  424. MODULE_DESCRIPTION("OMAP PDM SoC Interface");
  425. MODULE_LICENSE("GPL");