1 /* 2 * imx-pcm-dma-mx2.c -- ALSA Soc Audio Layer 3 * 4 * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de> 5 * 6 * This code is based on code copyrighted by Freescale, 7 * Liam Girdwood, Javier Martin and probably others. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 */ 14 #include <linux/platform_device.h> 15 #include <linux/dmaengine.h> 16 #include <linux/types.h> 17 #include <linux/module.h> 18 19 #include <sound/core.h> 20 #include <sound/pcm.h> 21 #include <sound/soc.h> 22 #include <sound/dmaengine_pcm.h> 23 24 #include "imx-pcm.h" 25 26 static bool filter(struct dma_chan *chan, void *param) 27 { 28 if (!imx_dma_is_general_purpose(chan)) 29 return false; 30 31 chan->private = param; 32 33 return true; 34 } 35 36 static const struct snd_pcm_hardware imx_pcm_hardware = { 37 .info = SNDRV_PCM_INFO_INTERLEAVED | 38 SNDRV_PCM_INFO_BLOCK_TRANSFER | 39 SNDRV_PCM_INFO_MMAP | 40 SNDRV_PCM_INFO_MMAP_VALID | 41 SNDRV_PCM_INFO_PAUSE | 42 SNDRV_PCM_INFO_RESUME, 43 .formats = SNDRV_PCM_FMTBIT_S16_LE, 44 .buffer_bytes_max = IMX_SSI_DMABUF_SIZE, 45 .period_bytes_min = 128, 46 .period_bytes_max = 65535, /* Limited by SDMA engine */ 47 .periods_min = 2, 48 .periods_max = 255, 49 .fifo_size = 0, 50 }; 51 52 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = { 53 .pcm_hardware = &imx_pcm_hardware, 54 .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config, 55 .compat_filter_fn = filter, 56 .prealloc_buffer_size = IMX_SSI_DMABUF_SIZE, 57 }; 58 59 int imx_pcm_dma_init(struct platform_device *pdev) 60 { 61 return devm_snd_dmaengine_pcm_register(&pdev->dev, 62 &imx_dmaengine_pcm_config, 63 SND_DMAENGINE_PCM_FLAG_NO_RESIDUE | 64 SND_DMAENGINE_PCM_FLAG_COMPAT); 65 } 66 EXPORT_SYMBOL_GPL(imx_pcm_dma_init); 67 68 MODULE_LICENSE("GPL"); 69