[PATCH v6 13/13] ASoC: stm32: add DFSDM DAI support

Arnaud Pouliquen arnaud.pouliquen at st.com
Mon Dec 4 00:58:42 PST 2017



On 12/02/2017 04:09 PM, Jonathan Cameron wrote:
> On Fri, 1 Dec 2017 18:40:20 +0100
> Arnaud Pouliquen <arnaud.pouliquen at st.com> wrote:
> 
>> Add driver to handle DAI interface for PDM microphones connected
>> to Digital Filter for Sigma Delta Modulators IP.
>> 
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
> 
> include tied up with the move of that enum in the earlier patch.
> Other than that the IIO stuff looks fine to me.
> 
> Mark, given this set is moderately invasive on the IIO side and
> should just drop in cleanly on the sound side of things, either
> I could take it via IIO or one of us can do an immutable branch
> and we take it through both trees.

Don't know if you saw the reply from Mark on V5:
"This is basically fine, if someone could send me a pull request and the
relevant patches when the IIO stuff is sorted out I'll give it a final
check and apply then."

> 
> Don't mind which but if I'm either taking the series or doing
> an immutable branch I'll obviously be waiting on your review!
> 
> Also need time for Rob to check the updating bindings.
> 
> Anyhow, it's coming together reasonably nicely in the end.
> Good work Arnaud!

Thanks! it will be a good achievement for me, not trivial this
peripheral to integrate :)
I'm waiting Rob's ack or remarks on patch 12/13 to send the next version.

Thanks and Regards
Arnaud

> 
> Jonathan
>> ---
>> V5 to V6 update:
>>  fix build warning
>>  
>>  sound/soc/stm/Kconfig        |  11 ++
>>  sound/soc/stm/Makefile       |   3 +
>>  sound/soc/stm/stm32_adfsdm.c | 386 +++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 400 insertions(+)
>>  create mode 100644 sound/soc/stm/stm32_adfsdm.c
>> 
>> diff --git a/sound/soc/stm/Kconfig b/sound/soc/stm/Kconfig
>> index 3398e6c..a78f770 100644
>> --- a/sound/soc/stm/Kconfig
>> +++ b/sound/soc/stm/Kconfig
>> @@ -28,4 +28,15 @@ config SND_SOC_STM32_SPDIFRX
>>        help
>>          Say Y if you want to enable S/PDIF capture for STM32
>>  
>> +config SND_SOC_STM32_DFSDM
>> +     tristate "SoC Audio support for STM32 DFSDM"
>> +     depends on (ARCH_STM32 && OF && STM32_DFSDM_ADC) || COMPILE_TEST
>> +     depends on SND_SOC
>> +     select SND_SOC_GENERIC_DMAENGINE_PCM
>> +     select SND_SOC_DMIC
>> +     select IIO_BUFFER_CB
>> +     help
>> +       Select this option to enable the STM32 Digital Filter
>> +       for Sigma Delta Modulators (DFSDM) driver used
>> +       in various STM32 series for digital microphone capture.
>>  endmenu
>> diff --git a/sound/soc/stm/Makefile b/sound/soc/stm/Makefile
>> index 4ed22e6..53e90e6 100644
>> --- a/sound/soc/stm/Makefile
>> +++ b/sound/soc/stm/Makefile
>> @@ -12,3 +12,6 @@ obj-$(CONFIG_SND_SOC_STM32_I2S) += snd-soc-stm32-i2s.o
>>  # SPDIFRX
>>  snd-soc-stm32-spdifrx-objs := stm32_spdifrx.o
>>  obj-$(CONFIG_SND_SOC_STM32_SPDIFRX) += snd-soc-stm32-spdifrx.o
>> +
>> +#DFSDM
>> +obj-$(CONFIG_SND_SOC_STM32_DFSDM) += stm32_adfsdm.o
>> diff --git a/sound/soc/stm/stm32_adfsdm.c b/sound/soc/stm/stm32_adfsdm.c
>> new file mode 100644
>> index 0000000..890ec24
>> --- /dev/null
>> +++ b/sound/soc/stm/stm32_adfsdm.c
>> @@ -0,0 +1,386 @@
>> +/*
>> + * This file is part of STM32 DFSDM ASoC DAI driver
>> + *
>> + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
>> + * Authors: Arnaud Pouliquen <arnaud.pouliquen at st.com>
>> + *          Olivier Moysan <olivier.moysan at st.com>
>> + *
>> + * License terms: GPL V2.0.
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms of the GNU General Public License version 2 as published by
>> + * the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope that it will be useful, but
>> + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
>> + * or FITNESS FOR A PARTICULAR PURPOSE.
>> + * See the GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along with
>> + * this program. If not, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +
>> +#include <linux/iio/iio.h>
> 
> I missed this before but a consumer should not need to include iio.h.
> I would guess it was about that enum that I want you to move to types.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;
>> +     bool allocated;
>> +};
>> +
>> +struct stm32_adfsdm_data {
>> +     unsigned int rate;      /* SNDRV_PCM_RATE value */
>> +     unsigned int freq;      /* frequency in Hz */
>> +};
>> +
>> +static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = {
>> +     .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
>> +         SNDRV_PCM_INFO_PAUSE,
>> +     .formats = SNDRV_PCM_FMTBIT_S32_LE,
>> +
>> +     .rate_min = 8000,
>> +     .rate_max = 32000,
>> +
>> +     .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);
>> +
>> +     if (priv->iio_active) {
>> +             iio_channel_stop_all_cb(priv->iio_cb);
>> +             priv->iio_active = false;
>> +     }
>> +}
>> +
>> +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;
>> +
>> +     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);
>> +             return ret;
>> +     }
>> +
>> +     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);
>> +     }
>> +
>> +     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;
>> +
>> +     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*/
>> +     if (dir == SND_SOC_CLOCK_IN) {
>> +             char str_freq[10];
>> +
>> +             snprintf(str_freq, sizeof(str_freq), "%d\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_S32_LE,
>> +                 .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 |
>> +                           SNDRV_PCM_RATE_32000),
>> +                 },
>> +     .ops = &stm32_adfsdm_dai_ops,
>> +};
>> +
>> +static const struct snd_soc_component_driver stm32_adfsdm_dai_component = {
>> +     .name = "stm32_dfsdm_audio",
>> +};
>> +
>> +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 = priv->substream->private_data;
>> +     u8 *pcm_buff = priv->pcm_buff;
>> +     u8 *src_buff = (u8 *)data;
>> +     unsigned int buff_size = snd_pcm_lib_buffer_bytes(priv->substream);
>> +     unsigned int period_size = snd_pcm_lib_period_bytes(priv->substream);
>> +     unsigned int old_pos = priv->pos;
>> +     unsigned int cur_size = size;
>> +
>> +     dev_dbg(rtd->dev, "%s: buff_add :%p, pos = %d, size = %lu\n",
>> +             __func__, &pcm_buff[priv->pos], priv->pos, size);
>> +
>> +     if ((priv->pos + size) > buff_size) {
>> +             memcpy(&pcm_buff[priv->pos], src_buff, buff_size - priv->pos);
>> +             cur_size -= buff_size - priv->pos;
>> +             priv->pos = 0;
>> +     }
>> +
>> +     memcpy(&pcm_buff[priv->pos], &src_buff[size - cur_size], cur_size);
>> +     priv->pos = (priv->pos + cur_size) % buff_size;
>> +
>> +     if (cur_size != size || (old_pos && (old_pos % period_size < size)))
>> +             snd_pcm_period_elapsed(priv->substream);
>> +
>> +     return 0;
>> +}
>> +
>> +static int stm32_adfsdm_trigger(struct snd_pcm_substream *substream, int cmd)
>> +{
>> +     struct snd_soc_pcm_runtime *rtd = substream->private_data;
>> +     struct stm32_adfsdm_priv *priv =
>> +             snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +
>> +     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);
>> +     default:
>> +             return -EINVAL;
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static int stm32_adfsdm_pcm_open(struct snd_pcm_substream *substream)
>> +{
>> +     struct snd_soc_pcm_runtime *rtd = substream->private_data;
>> +     struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +     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_pcm_substream *substream)
>> +{
>> +     struct snd_soc_pcm_runtime *rtd = substream->private_data;
>> +     struct stm32_adfsdm_priv *priv =
>> +             snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +
>> +     snd_pcm_lib_free_pages(substream);
>> +     priv->substream = NULL;
>> +
>> +     return 0;
>> +}
>> +
>> +static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer(
>> +                                         struct snd_pcm_substream *substream)
>> +{
>> +     struct snd_soc_pcm_runtime *rtd = substream->private_data;
>> +     struct stm32_adfsdm_priv *priv =
>> +             snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +
>> +     return bytes_to_frames(substream->runtime, priv->pos);
>> +}
>> +
>> +static int stm32_adfsdm_pcm_hw_params(struct snd_pcm_substream *substream,
>> +                                   struct snd_pcm_hw_params *params)
>> +{
>> +     struct snd_soc_pcm_runtime *rtd = substream->private_data;
>> +     struct stm32_adfsdm_priv *priv =
>> +             snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +     int ret;
>> +
>> +     ret =  snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
>> +     if (ret < 0)
>> +             return ret;
>> +     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_hw_free(struct snd_pcm_substream *substream)
>> +{
>> +     snd_pcm_lib_free_pages(substream);
>> +
>> +     return 0;
>> +}
>> +
>> +static struct snd_pcm_ops stm32_adfsdm_pcm_ops = {
>> +     .open           = stm32_adfsdm_pcm_open,
>> +     .close          = stm32_adfsdm_pcm_close,
>> +     .hw_params      = stm32_adfsdm_pcm_hw_params,
>> +     .hw_free        = stm32_adfsdm_pcm_hw_free,
>> +     .trigger        = stm32_adfsdm_trigger,
>> +     .pointer        = stm32_adfsdm_pcm_pointer,
>> +};
>> +
>> +static int stm32_adfsdm_pcm_new(struct snd_soc_pcm_runtime *rtd)
>> +{
>> +     struct snd_pcm *pcm = rtd->pcm;
>> +     struct stm32_adfsdm_priv *priv =
>> +             snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +     unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE;
>> +     int ret;
>> +
>> +     /*
>> +      * FIXME :
>> +      * A platform as been registered per DAI.
>> +      * In soc_new_pcm function, pcm_new callback is called for each
>> +      * component of the sound card. So if n dai links are created this
>> +      * function is called n times.
>> +      */
>> +     if (priv->allocated)
>> +             return 0;
>> +
>> +     ret = snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
>> +                                                 priv->dev, size, size);
>> +     if (!ret)
>> +             priv->allocated = true;
>> +
>> +     return ret;
>> +}
>> +
>> +static void stm32_adfsdm_pcm_free(struct snd_pcm *pcm)
>> +{
>> +     struct snd_pcm_substream *substream;
>> +     struct snd_soc_pcm_runtime *rtd;
>> +     struct stm32_adfsdm_priv *priv;
>> +
>> +     substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
>> +     if (substream) {
>> +             rtd = substream->private_data;
>> +             priv = snd_soc_dai_get_drvdata(rtd->cpu_dai);
>> +
>> +             snd_pcm_lib_preallocate_free_for_all(pcm);
>> +             priv->allocated = false;
>> +     }
>> +}
>> +
>> +static struct snd_soc_platform_driver stm32_adfsdm_soc_platform = {
>> +     .ops            = &stm32_adfsdm_pcm_ops,
>> +     .pcm_new        = stm32_adfsdm_pcm_new,
>> +     .pcm_free       = stm32_adfsdm_pcm_free,
>> +};
>> +
>> +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;
>> +     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;
>> +
>> +     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, NULL, NULL);
>> +     if (IS_ERR(priv->iio_cb))
>> +             return PTR_ERR(priv->iio_ch);
>> +
>> +     ret = devm_snd_soc_register_platform(&pdev->dev,
>> +                                          &stm32_adfsdm_soc_platform);
>> +     if (ret < 0)
>> +             dev_err(&pdev->dev, "%s: Failed to register PCM platform\n",
>> +                     __func__);
>> +
>> +     return ret;
>> +}
>> +
>> +static struct platform_driver stm32_adfsdm_driver = {
>> +     .driver = {
>> +                .name = STM32_ADFSDM_DRV_NAME,
>> +                .of_match_table = stm32_adfsdm_of_match,
>> +                },
>> +     .probe = stm32_adfsdm_probe,
>> +};
>> +
>> +module_platform_driver(stm32_adfsdm_driver);
>> +
>> +MODULE_DESCRIPTION("stm32 DFSDM DAI driver");
>> +MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen at st.com>");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME);
> 



More information about the linux-arm-kernel mailing list