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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com4 * Author: Peter Ujfalusi <peter.ujfalusi@ti.com>5 */6 7#include <linux/device.h>8#include <linux/module.h>9#include <sound/core.h>10#include <sound/pcm.h>11#include <sound/pcm_params.h>12#include <sound/soc.h>13#include <sound/dmaengine_pcm.h>14 15#include "sdma-pcm.h"16 17static const struct snd_pcm_hardware sdma_pcm_hardware = {18 .info = SNDRV_PCM_INFO_MMAP |19 SNDRV_PCM_INFO_MMAP_VALID |20 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME |21 SNDRV_PCM_INFO_NO_PERIOD_WAKEUP |22 SNDRV_PCM_INFO_INTERLEAVED,23 .period_bytes_min = 32,24 .period_bytes_max = 64 * 1024,25 .buffer_bytes_max = 128 * 1024,26 .periods_min = 2,27 .periods_max = 255,28};29 30static const struct snd_dmaengine_pcm_config sdma_dmaengine_pcm_config = {31 .pcm_hardware = &sdma_pcm_hardware,32 .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,33 .prealloc_buffer_size = 128 * 1024,34};35 36int sdma_pcm_platform_register(struct device *dev,37 char *txdmachan, char *rxdmachan)38{39 struct snd_dmaengine_pcm_config *config;40 unsigned int flags = 0;41 42 /* Standard names for the directions: 'tx' and 'rx' */43 if (!txdmachan && !rxdmachan)44 return devm_snd_dmaengine_pcm_register(dev,45 &sdma_dmaengine_pcm_config, 0);46 47 config = devm_kzalloc(dev, sizeof(*config), GFP_KERNEL);48 if (!config)49 return -ENOMEM;50 51 *config = sdma_dmaengine_pcm_config;52 53 if (!txdmachan || !rxdmachan) {54 /* One direction only PCM */55 flags |= SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX;56 if (!txdmachan) {57 txdmachan = rxdmachan;58 rxdmachan = NULL;59 }60 }61 62 config->chan_names[0] = txdmachan;63 config->chan_names[1] = rxdmachan;64 65 return devm_snd_dmaengine_pcm_register(dev, config, flags);66}67EXPORT_SYMBOL_GPL(sdma_pcm_platform_register);68 69MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");70MODULE_DESCRIPTION("sDMA PCM ASoC platform driver");71MODULE_LICENSE("GPL v2");72