linux/sound/soc/soc-utils.c
Mark Brown cefcc03ffc ASoC: Provide a more complete DMA driver stub
Allow userspace applications to do more parameter setting by providing a
more complete stub DMA driver specifying a wildcard set of formats and
channels and essentially random values for the DMA parameters. This is
required for useful runtime operation of the dummy DMA driver until we
are able to figure out how to power up links and do hw_params() from DAPM.

Sending to stable as without this the dummy driver is not terribly
useful.

Reported-by: Kyung-Kwee Ryu <Kyung-Kwee.Ryu@wolfsonmicro.com>
Tested-by: Kyung-Kwee Ryu <Kyung-Kwee.Ryu@wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
2011-12-06 10:05:07 +00:00

140 lines
3.3 KiB
C

/*
* soc-util.c -- ALSA SoC Audio Layer utility functions
*
* Copyright 2009 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
* Liam Girdwood <lrg@slimlogic.co.uk>
*
*
* 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/platform_device.h>
#include <linux/export.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
{
return sample_size * channels * tdm_slots;
}
EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params)
{
int sample_size;
sample_size = snd_pcm_format_width(params_format(params));
if (sample_size < 0)
return sample_size;
return snd_soc_calc_frame_size(sample_size, params_channels(params),
1);
}
EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots)
{
return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots);
}
EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
{
int ret;
ret = snd_soc_params_to_frame_size(params);
if (ret > 0)
return ret * params_rate(params);
else
return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
static const struct snd_pcm_hardware dummy_dma_hardware = {
.formats = 0xffffffff,
.channels_min = 1,
.channels_max = UINT_MAX,
/* Random values to keep userspace happy when checking constraints */
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER,
.buffer_bytes_max = 128*1024,
.period_bytes_min = PAGE_SIZE,
.period_bytes_max = PAGE_SIZE*2,
.periods_min = 2,
.periods_max = 128,
};
static int dummy_dma_open(struct snd_pcm_substream *substream)
{
snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware);
return 0;
}
static struct snd_pcm_ops dummy_dma_ops = {
.open = dummy_dma_open,
.ioctl = snd_pcm_lib_ioctl,
};
static struct snd_soc_platform_driver dummy_platform = {
.ops = &dummy_dma_ops,
};
static __devinit int snd_soc_dummy_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &dummy_platform);
}
static __devexit int snd_soc_dummy_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver soc_dummy_driver = {
.driver = {
.name = "snd-soc-dummy",
.owner = THIS_MODULE,
},
.probe = snd_soc_dummy_probe,
.remove = __devexit_p(snd_soc_dummy_remove),
};
static struct platform_device *soc_dummy_dev;
int __init snd_soc_util_init(void)
{
int ret;
soc_dummy_dev = platform_device_alloc("snd-soc-dummy", -1);
if (!soc_dummy_dev)
return -ENOMEM;
ret = platform_device_add(soc_dummy_dev);
if (ret != 0) {
platform_device_put(soc_dummy_dev);
return ret;
}
ret = platform_driver_register(&soc_dummy_driver);
if (ret != 0)
platform_device_unregister(soc_dummy_dev);
return ret;
}
void __exit snd_soc_util_exit(void)
{
platform_device_unregister(soc_dummy_dev);
platform_driver_unregister(&soc_dummy_driver);
}