// SPDX-License-Identifier: GPL-2.0
/*
* This file is part of STM32 DFSDM ASoC DAI driver
*
* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
* Authors: Arnaud Pouliquen <[email protected]>
* Olivier Moysan <[email protected]>
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/consumer.h>
#include <linux/iio/adc/stm32-dfsdm-adc.h>
#include <sound/pcm.h>
#include <sound/soc.h>
#define STM32_ADFSDM_DRV_NAME "stm32-adfsdm"
#define DFSDM_MAX_PERIOD_SIZE (PAGE_SIZE / 2)
#define DFSDM_MAX_PERIODS 6
struct stm32_adfsdm_priv {
struct snd_soc_dai_driver dai_drv;
struct snd_pcm_substream *substream;
struct device *dev;
/* IIO */
struct iio_channel *iio_ch;
struct iio_cb_buffer *iio_cb;
bool iio_active;
/* PCM buffer */
unsigned char *pcm_buff;
unsigned int pos;
struct mutex lock; /* protect against race condition on iio state */
};
static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = {
.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_PAUSE,
.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,
.channels_min = 1,
.channels_max = 1,
.periods_min = 2,
.periods_max = DFSDM_MAX_PERIODS,
.period_bytes_max = DFSDM_MAX_PERIOD_SIZE,
.buffer_bytes_max = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE
};
static void stm32_adfsdm_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
mutex_lock(&priv->lock);
if (priv->iio_active) {
iio_channel_stop_all_cb(priv->iio_cb);
priv->iio_active = false;
}
mutex_unlock(&priv->lock);
}
static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
int ret;
mutex_lock(&priv->lock);
if (priv->iio_active) {
iio_channel_stop_all_cb(priv->iio_cb);
priv->iio_active = false;
}
ret = iio_write_channel_attribute(priv->iio_ch,
substream->runtime->rate, 0,
IIO_CHAN_INFO_SAMP_FREQ);
if (ret < 0) {
dev_err(dai->dev, "%s: Failed to set %d sampling rate\n",
__func__, substream->runtime->rate);
goto out;
}
if (!priv->iio_active) {
ret = iio_channel_start_all_cb(priv->iio_cb);
if (!ret)
priv->iio_active = true;
else
dev_err(dai->dev, "%s: IIO channel start failed (%d)\n",
__func__, ret);
}
out:
mutex_unlock(&priv->lock);
return ret;
}
static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id,
unsigned int freq, int dir)
{
struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
ssize_t size;
char str_freq[10];
dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq);
/* Set IIO frequency if CODEC is master as clock comes from SPI_IN */
snprintf(str_freq, sizeof(str_freq), "%u\n", freq);
size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq",
str_freq, sizeof(str_freq));
if (size != sizeof(str_freq)) {
dev_err(dai->dev, "%s: Failed to set SPI clock\n",
__func__);
return -EINVAL;
}
return 0;
}
static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = {
.shutdown = stm32_adfsdm_shutdown,
.prepare = stm32_adfsdm_dai_prepare,
.set_sysclk = stm32_adfsdm_set_sysclk,
};
static const struct snd_soc_dai_driver stm32_adfsdm_dai = {
.capture = {
.channels_min = 1,
.channels_max = 1,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S32_LE,
.rates = SNDRV_PCM_RATE_CONTINUOUS,
.rate_min = 8000,
.rate_max = 48000,
},
.ops = &stm32_adfsdm_dai_ops,
};
static const struct snd_soc_component_driver stm32_adfsdm_dai_component = {
.name = "stm32_dfsdm_audio",
.legacy_dai_naming = 1,
};
static void stm32_memcpy_32to16(void *dest, const void *src, size_t n)
{
unsigned int i = 0;
u16 *d = (u16 *)dest, *s = (u16 *)src;
s++;
for (i = n >> 1; i > 0; i--) {
*d++ = *s++;
s++;
}
}
static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private)
{
struct stm32_adfsdm_priv *priv = private;
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(priv->substream);
u8 *pcm_buff = priv->pcm_buff;
u8 *src_buff = (u8 *)data;
unsigned int old_pos = priv->pos;
size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream);
size_t period_size = snd_pcm_lib_period_bytes(priv->substream);
size_t cur_size, src_size = size;
snd_pcm_format_t format = priv->substream->runtime->format;
if (format == SNDRV_PCM_FORMAT_S16_LE)
src_size >>= 1;
cur_size = src_size;
dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n",
__func__, &pcm_buff[priv->pos], priv->pos, src_size);
if ((priv->pos + src_size) > buff_size) {
if (format == SNDRV_PCM_FORMAT_S16_LE)
stm32_memcpy_32to16(&pcm_buff[priv->pos], src_buff,
buff_size - priv->pos);
else
memcpy(&pcm_buff[priv->pos], src_buff,
buff_size - priv->pos);
cur_size -= buff_size - priv->pos;
priv->pos = 0;
}
if (format == SNDRV_PCM_FORMAT_S16_LE)
stm32_memcpy_32to16(&pcm_buff[priv->pos],
&src_buff[src_size - cur_size], cur_size);
else
memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size],
cur_size);
priv->pos = (priv->pos + cur_size) % buff_size;
if (cur_size != src_size || (old_pos && (old_pos % period_size < size)))
snd_pcm_period_elapsed(priv->substream);
return 0;
}
static int stm32_adfsdm_trigger(struct snd_soc_component *component,
struct snd_pcm_substream *substream, int cmd)
{
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
struct stm32_adfsdm_priv *priv =
snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
priv->pos = 0;
return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev,
stm32_afsdm_pcm_cb, priv);
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_STOP:
return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev);
}
return -EINVAL;
}
static int stm32_adfsdm_pcm_open(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
int ret;
ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw);
if (!ret)
priv->substream = substream;
return ret;
}
static int stm32_adfsdm_pcm_close(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
struct stm32_adfsdm_priv *priv =
snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
priv->substream = NULL;
return 0;
}
static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer(
struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
struct stm32_adfsdm_priv *priv =
snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
return bytes_to_frames(substream->runtime, priv->pos);
}
static int stm32_adfsdm_pcm_hw_params(struct snd_soc_component *component,
struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
struct stm32_adfsdm_priv *priv =
snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
priv->pcm_buff = substream->runtime->dma_area;
return iio_channel_cb_set_buffer_watermark(priv->iio_cb,
params_period_size(params));
}
static int stm32_adfsdm_pcm_new(struct snd_soc_component *component,
struct snd_soc_pcm_runtime *rtd)
{
struct snd_pcm *pcm = rtd->pcm;
struct stm32_adfsdm_priv *priv =
snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE;
snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
priv->dev, size, size);
return 0;
}
static int stm32_adfsdm_dummy_cb(const void *data, void *private)
{
/*
* This dummy callback is requested by iio_channel_get_all_cb() API,
* but the stm32_dfsdm_get_buff_cb() API is used instead, to optimize
* DMA transfers.
*/
return 0;
}
static void stm32_adfsdm_cleanup(void *data)
{
iio_channel_release_all_cb(data);
}
static struct snd_soc_component_driver stm32_adfsdm_soc_platform = {
.open = stm32_adfsdm_pcm_open,
.close = stm32_adfsdm_pcm_close,
.hw_params = stm32_adfsdm_pcm_hw_params,
.trigger = stm32_adfsdm_trigger,
.pointer = stm32_adfsdm_pcm_pointer,
.pcm_construct = stm32_adfsdm_pcm_new,
};
static const struct of_device_id stm32_adfsdm_of_match[] = {
{.compatible = "st,stm32h7-dfsdm-dai"},
{}
};
MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match);
static int stm32_adfsdm_probe(struct platform_device *pdev)
{
struct stm32_adfsdm_priv *priv;
struct snd_soc_component *component;
int ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->dev = &pdev->dev;
priv->dai_drv = stm32_adfsdm_dai;
mutex_init(&priv->lock);
dev_set_drvdata(&pdev->dev, priv);
ret = devm_snd_soc_register_component(&pdev->dev,
&stm32_adfsdm_dai_component,
&priv->dai_drv, 1);
if (ret < 0)
return ret;
/* Associate iio channel */
priv->iio_ch = devm_iio_channel_get_all(&pdev->dev);
if (IS_ERR(priv->iio_ch))
return PTR_ERR(priv->iio_ch);
priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL);
if (IS_ERR(priv->iio_cb))
return PTR_ERR(priv->iio_cb);
ret = devm_add_action_or_reset(&pdev->dev, stm32_adfsdm_cleanup, priv->iio_cb);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to add action\n");
return ret;
}
component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL);
if (!component)
return -ENOMEM;
ret = snd_soc_component_initialize(component,
&stm32_adfsdm_soc_platform,
&pdev->dev);
if (ret < 0)
return ret;
#ifdef CONFIG_DEBUG_FS
component->debugfs_prefix = "pcm";
#endif
ret = snd_soc_add_component(component, NULL, 0);
if (ret < 0) {
dev_err(&pdev->dev, "%s: Failed to register PCM platform\n",
__func__);
return ret;
}
pm_runtime_enable(&pdev->dev);
return ret;
}
static void stm32_adfsdm_remove(struct platform_device *pdev)
{
snd_soc_unregister_component(&pdev->dev);
pm_runtime_disable(&pdev->dev);
}
static struct platform_driver stm32_adfsdm_driver = {
.driver = {
.name = STM32_ADFSDM_DRV_NAME,
.of_match_table = stm32_adfsdm_of_match,
},
.probe = stm32_adfsdm_probe,
.remove = stm32_adfsdm_remove,
};
module_platform_driver(stm32_adfsdm_driver);
MODULE_DESCRIPTION("stm32 DFSDM DAI driver");
MODULE_AUTHOR("Arnaud Pouliquen <[email protected]>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME);
Codebase Browser
linux