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@st.com --- sound/soc/stm/Kconfig | 11 ++ sound/soc/stm/Makefile | 3 + sound/soc/stm/stm32_adfsdm.c | 347 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 361 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..af50891 --- /dev/null +++ b/sound/soc/stm/stm32_adfsdm.c @@ -0,0 +1,347 @@ +// 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 arnaud.pouliquen@st.com + * Olivier Moysan olivier.moysan@st.com + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.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; +}; + +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; + 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), "%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 = %zu\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); + } + + return -EINVAL; +} + +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; + + return snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, + priv->dev, size, size); +} + +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); + } +} + +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@st.com"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME);