soc/ti/sdma-pcm.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *  Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com
0004  *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
0005  */
0006
0007 #include <linux/device.h>
0008 #include <linux/module.h>
0009 #include <sound/core.h>
0010 #include <sound/pcm.h>
0011 #include <sound/pcm_params.h>
0012 #include <sound/soc.h>
0013 #include <sound/dmaengine_pcm.h>
0014
0015 #include "sdma-pcm.h"
0016
0017 static const struct snd_pcm_hardware sdma_pcm_hardware = {
0018     .info           = SNDRV_PCM_INFO_MMAP |
0019                   SNDRV_PCM_INFO_MMAP_VALID |
0020                   SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME |
0021                   SNDRV_PCM_INFO_NO_PERIOD_WAKEUP |
0022                   SNDRV_PCM_INFO_INTERLEAVED,
0023     .period_bytes_min   = 32,
0024     .period_bytes_max   = 64 * 1024,
0025     .buffer_bytes_max   = 128 * 1024,
0026     .periods_min        = 2,
0027     .periods_max        = 255,
0028 };
0029
0030 static const struct snd_dmaengine_pcm_config sdma_dmaengine_pcm_config = {
0031     .pcm_hardware = &sdma_pcm_hardware,
0032     .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
0033     .prealloc_buffer_size = 128 * 1024,
0034 };
0035
0036 int sdma_pcm_platform_register(struct device *dev,
0037                    char *txdmachan, char *rxdmachan)
0038 {
0039     struct snd_dmaengine_pcm_config *config;
0040     unsigned int flags = 0;
0041
0042     /* Standard names for the directions: 'tx' and 'rx' */
0043     if (!txdmachan && !rxdmachan)
0044         return devm_snd_dmaengine_pcm_register(dev,
0045                         &sdma_dmaengine_pcm_config, 0);
0046
0047     config = devm_kzalloc(dev, sizeof(*config), GFP_KERNEL);
0048     if (!config)
0049         return -ENOMEM;
0050
0051     *config = sdma_dmaengine_pcm_config;
0052
0053     if (!txdmachan || !rxdmachan) {
0054         /* One direction only PCM */
0055         flags |= SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX;
0056         if (!txdmachan) {
0057             txdmachan = rxdmachan;
0058             rxdmachan = NULL;
0059         }
0060     }
0061
0062     config->chan_names[0] = txdmachan;
0063     config->chan_names[1] = rxdmachan;
0064
0065     return devm_snd_dmaengine_pcm_register(dev, config, flags);
0066 }
0067 EXPORT_SYMBOL_GPL(sdma_pcm_platform_register);
0068
0069 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
0070 MODULE_DESCRIPTION("sDMA PCM ASoC platform driver");
0071 MODULE_LICENSE("GPL v2");