1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com 4 * 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 17 static 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 30 static 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 36 int 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 } 67 EXPORT_SYMBOL_GPL(sdma_pcm_platform_register); 68 69 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); 70 MODULE_DESCRIPTION("sDMA PCM ASoC platform driver"); 71 MODULE_LICENSE("GPL v2"); 72