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b0a23b8b36
The ASoC core assumes that the PCM component of the ASoC card transparently moves data around and does not impose any restrictions on the memory layout or the transfer speed. It ignores all fields from the snd_pcm_hardware struct for the PCM driver that are related to this. Setting these fields in the PCM driver might suggest otherwise though, so rather not set them. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mark Brown <broonie@linaro.org>
69 lines
1.8 KiB
C
69 lines
1.8 KiB
C
/*
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* imx-pcm-dma-mx2.c -- ALSA Soc Audio Layer
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*
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* Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
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*
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* This code is based on code copyrighted by Freescale,
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* Liam Girdwood, Javier Martin and probably others.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*/
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#include <linux/platform_device.h>
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#include <linux/dmaengine.h>
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#include <linux/types.h>
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#include <linux/module.h>
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#include <sound/core.h>
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#include <sound/pcm.h>
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#include <sound/soc.h>
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#include <sound/dmaengine_pcm.h>
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#include "imx-pcm.h"
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static bool filter(struct dma_chan *chan, void *param)
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{
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if (!imx_dma_is_general_purpose(chan))
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return false;
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chan->private = param;
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return true;
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}
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static const struct snd_pcm_hardware imx_pcm_hardware = {
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.info = SNDRV_PCM_INFO_INTERLEAVED |
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SNDRV_PCM_INFO_BLOCK_TRANSFER |
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SNDRV_PCM_INFO_MMAP |
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SNDRV_PCM_INFO_MMAP_VALID |
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SNDRV_PCM_INFO_PAUSE |
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SNDRV_PCM_INFO_RESUME,
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.formats = SNDRV_PCM_FMTBIT_S16_LE,
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.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
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.period_bytes_min = 128,
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.period_bytes_max = 65535, /* Limited by SDMA engine */
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.periods_min = 2,
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.periods_max = 255,
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.fifo_size = 0,
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};
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static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = {
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.pcm_hardware = &imx_pcm_hardware,
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.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
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.compat_filter_fn = filter,
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.prealloc_buffer_size = IMX_SSI_DMABUF_SIZE,
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};
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int imx_pcm_dma_init(struct platform_device *pdev)
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{
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return devm_snd_dmaengine_pcm_register(&pdev->dev,
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&imx_dmaengine_pcm_config,
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SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
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SND_DMAENGINE_PCM_FLAG_COMPAT);
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}
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EXPORT_SYMBOL_GPL(imx_pcm_dma_init);
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MODULE_LICENSE("GPL");
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