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 18 #include <sound/core.h> 19 #include <sound/pcm.h> 20 #include <sound/soc.h> 21 #include <sound/dmaengine_pcm.h> 22 23 #include "imx-pcm.h" 24 25 static bool filter(struct dma_chan *chan, void *param) 26 { 27 struct snd_dmaengine_dai_dma_data *dma_data = param; 28 29 if (!imx_dma_is_general_purpose(chan)) 30 return false; 31 32 chan->private = dma_data->filter_data; 33 34 return true; 35 } 36 37 static const struct snd_pcm_hardware imx_pcm_hardware = { 38 .info = SNDRV_PCM_INFO_INTERLEAVED | 39 SNDRV_PCM_INFO_BLOCK_TRANSFER | 40 SNDRV_PCM_INFO_MMAP | 41 SNDRV_PCM_INFO_MMAP_VALID | 42 SNDRV_PCM_INFO_PAUSE | 43 SNDRV_PCM_INFO_RESUME, 44 .formats = SNDRV_PCM_FMTBIT_S16_LE, 45 .rate_min = 8000, 46 .channels_min = 2, 47 .channels_max = 2, 48 .buffer_bytes_max = IMX_SSI_DMABUF_SIZE, 49 .period_bytes_min = 128, 50 .period_bytes_max = 65535, /* Limited by SDMA engine */ 51 .periods_min = 2, 52 .periods_max = 255, 53 .fifo_size = 0, 54 }; 55 56 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = { 57 .pcm_hardware = &imx_pcm_hardware, 58 .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config, 59 .compat_filter_fn = filter, 60 .prealloc_buffer_size = IMX_SSI_DMABUF_SIZE, 61 }; 62 63 int imx_pcm_dma_init(struct platform_device *pdev) 64 { 65 return snd_dmaengine_pcm_register(&pdev->dev, &imx_dmaengine_pcm_config, 66 SND_DMAENGINE_PCM_FLAG_NO_RESIDUE | 67 SND_DMAENGINE_PCM_FLAG_NO_DT | 68 SND_DMAENGINE_PCM_FLAG_COMPAT); 69 } 70 EXPORT_SYMBOL_GPL(imx_pcm_dma_init); 71 72 void imx_pcm_dma_exit(struct platform_device *pdev) 73 { 74 snd_dmaengine_pcm_unregister(&pdev->dev); 75 } 76 EXPORT_SYMBOL_GPL(imx_pcm_dma_exit); 77