linux_dsm_epyc7002/sound/soc/fsl/imx-pcm-dma.c
Lars-Peter Clausen 9883ab229d ASoC: dmaengine-pcm: Rename and deprecate snd_dmaengine_pcm_pointer
Currently the sound dmaengine pcm helper functions implement the pcm_pointer
callback by trying to count the number of elapsed periods. This is done by
advancing the stream position in the dmaengine callback by one period.
Unfortunately there is no guarantee that the callback will be called for each
elapsed period. It may be possible that under high system load it is only called
once for multiple elapsed periods. This patch renames the current implementation
and documents its shortcomings and that it should not be used anymore in new
drivers.

The next patch will introduce a new snd_dmaengine_pcm_pointer which will be
implemented based on querying the current stream position from the dma device.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by Vinod Koul <vinod.koul@linux.intel.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-20 15:38:32 +01:00

177 lines
4.5 KiB
C

/*
* imx-pcm-dma-mx2.c -- ALSA Soc Audio Layer
*
* Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
*
* This code is based on code copyrighted by Freescale,
* Liam Girdwood, Javier Martin and probably others.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>
#include <linux/types.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/dmaengine_pcm.h>
#include <mach/dma.h>
#include "imx-pcm.h"
static bool filter(struct dma_chan *chan, void *param)
{
if (!imx_dma_is_general_purpose(chan))
return false;
chan->private = param;
return true;
}
static int snd_imx_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
struct imx_pcm_dma_params *dma_params;
struct dma_slave_config slave_config;
int ret;
dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
ret = snd_hwparams_to_dma_slave_config(substream, params, &slave_config);
if (ret)
return ret;
slave_config.device_fc = false;
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
slave_config.dst_addr = dma_params->dma_addr;
slave_config.dst_maxburst = dma_params->burstsize;
} else {
slave_config.src_addr = dma_params->dma_addr;
slave_config.src_maxburst = dma_params->burstsize;
}
ret = dmaengine_slave_config(chan, &slave_config);
if (ret)
return ret;
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
return 0;
}
static struct snd_pcm_hardware snd_imx_hardware = {
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_PAUSE |
SNDRV_PCM_INFO_RESUME,
.formats = SNDRV_PCM_FMTBIT_S16_LE,
.rate_min = 8000,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
.period_bytes_min = 128,
.period_bytes_max = 65535, /* Limited by SDMA engine */
.periods_min = 2,
.periods_max = 255,
.fifo_size = 0,
};
static int snd_imx_open(struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct imx_pcm_dma_params *dma_params;
struct imx_dma_data *dma_data;
int ret;
snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
dma_data = kzalloc(sizeof(*dma_data), GFP_KERNEL);
dma_data->peripheral_type = dma_params->shared_peripheral ?
IMX_DMATYPE_SSI_SP : IMX_DMATYPE_SSI;
dma_data->priority = DMA_PRIO_HIGH;
dma_data->dma_request = dma_params->dma;
ret = snd_dmaengine_pcm_open(substream, filter, dma_data);
if (ret) {
kfree(dma_data);
return 0;
}
snd_dmaengine_pcm_set_data(substream, dma_data);
return 0;
}
static int snd_imx_close(struct snd_pcm_substream *substream)
{
struct imx_dma_data *dma_data = snd_dmaengine_pcm_get_data(substream);
snd_dmaengine_pcm_close(substream);
kfree(dma_data);
return 0;
}
static struct snd_pcm_ops imx_pcm_ops = {
.open = snd_imx_open,
.close = snd_imx_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_imx_pcm_hw_params,
.trigger = snd_dmaengine_pcm_trigger,
.pointer = snd_dmaengine_pcm_pointer_no_residue,
.mmap = snd_imx_pcm_mmap,
};
static struct snd_soc_platform_driver imx_soc_platform_mx2 = {
.ops = &imx_pcm_ops,
.pcm_new = imx_pcm_new,
.pcm_free = imx_pcm_free,
};
static int __devinit imx_soc_platform_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &imx_soc_platform_mx2);
}
static int __devexit imx_soc_platform_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver imx_pcm_driver = {
.driver = {
.name = "imx-pcm-audio",
.owner = THIS_MODULE,
},
.probe = imx_soc_platform_probe,
.remove = __devexit_p(imx_soc_platform_remove),
};
module_platform_driver(imx_pcm_driver);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:imx-pcm-audio");