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1// SPDX-License-Identifier: GPL-2.02/*3 * This file is part of STM32 DFSDM ASoC DAI driver4 *5 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved6 * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>7 * Olivier Moysan <olivier.moysan@st.com>8 */9 10#include <linux/clk.h>11#include <linux/module.h>12#include <linux/mutex.h>13#include <linux/platform_device.h>14#include <linux/slab.h>15#include <linux/pm_runtime.h>16#include <linux/iio/iio.h>17#include <linux/iio/consumer.h>18#include <linux/iio/adc/stm32-dfsdm-adc.h>19 20#include <sound/pcm.h>21#include <sound/soc.h>22 23#define STM32_ADFSDM_DRV_NAME "stm32-adfsdm"24 25#define DFSDM_MAX_PERIOD_SIZE (PAGE_SIZE / 2)26#define DFSDM_MAX_PERIODS 627 28struct stm32_adfsdm_priv {29 struct snd_soc_dai_driver dai_drv;30 struct snd_pcm_substream *substream;31 struct device *dev;32 33 /* IIO */34 struct iio_channel *iio_ch;35 struct iio_cb_buffer *iio_cb;36 bool iio_active;37 38 /* PCM buffer */39 unsigned char *pcm_buff;40 unsigned int pos;41 42 struct mutex lock; /* protect against race condition on iio state */43};44 45static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = {46 .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |47 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_PAUSE,48 .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,49 50 .channels_min = 1,51 .channels_max = 1,52 53 .periods_min = 2,54 .periods_max = DFSDM_MAX_PERIODS,55 56 .period_bytes_max = DFSDM_MAX_PERIOD_SIZE,57 .buffer_bytes_max = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE58};59 60static void stm32_adfsdm_shutdown(struct snd_pcm_substream *substream,61 struct snd_soc_dai *dai)62{63 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);64 65 mutex_lock(&priv->lock);66 if (priv->iio_active) {67 iio_channel_stop_all_cb(priv->iio_cb);68 priv->iio_active = false;69 }70 mutex_unlock(&priv->lock);71}72 73static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream,74 struct snd_soc_dai *dai)75{76 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);77 int ret;78 79 mutex_lock(&priv->lock);80 if (priv->iio_active) {81 iio_channel_stop_all_cb(priv->iio_cb);82 priv->iio_active = false;83 }84 85 ret = iio_write_channel_attribute(priv->iio_ch,86 substream->runtime->rate, 0,87 IIO_CHAN_INFO_SAMP_FREQ);88 if (ret < 0) {89 dev_err(dai->dev, "%s: Failed to set %d sampling rate\n",90 __func__, substream->runtime->rate);91 goto out;92 }93 94 if (!priv->iio_active) {95 ret = iio_channel_start_all_cb(priv->iio_cb);96 if (!ret)97 priv->iio_active = true;98 else99 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n",100 __func__, ret);101 }102 103out:104 mutex_unlock(&priv->lock);105 106 return ret;107}108 109static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id,110 unsigned int freq, int dir)111{112 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);113 ssize_t size;114 char str_freq[10];115 116 dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq);117 118 /* Set IIO frequency if CODEC is master as clock comes from SPI_IN */119 120 snprintf(str_freq, sizeof(str_freq), "%u\n", freq);121 size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq",122 str_freq, sizeof(str_freq));123 if (size != sizeof(str_freq)) {124 dev_err(dai->dev, "%s: Failed to set SPI clock\n",125 __func__);126 return -EINVAL;127 }128 return 0;129}130 131static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = {132 .shutdown = stm32_adfsdm_shutdown,133 .prepare = stm32_adfsdm_dai_prepare,134 .set_sysclk = stm32_adfsdm_set_sysclk,135};136 137static const struct snd_soc_dai_driver stm32_adfsdm_dai = {138 .capture = {139 .channels_min = 1,140 .channels_max = 1,141 .formats = SNDRV_PCM_FMTBIT_S16_LE |142 SNDRV_PCM_FMTBIT_S32_LE,143 .rates = SNDRV_PCM_RATE_CONTINUOUS,144 .rate_min = 8000,145 .rate_max = 48000,146 },147 .ops = &stm32_adfsdm_dai_ops,148};149 150static const struct snd_soc_component_driver stm32_adfsdm_dai_component = {151 .name = "stm32_dfsdm_audio",152 .legacy_dai_naming = 1,153};154 155static void stm32_memcpy_32to16(void *dest, const void *src, size_t n)156{157 unsigned int i = 0;158 u16 *d = (u16 *)dest, *s = (u16 *)src;159 160 s++;161 for (i = n >> 1; i > 0; i--) {162 *d++ = *s++;163 s++;164 }165}166 167static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private)168{169 struct stm32_adfsdm_priv *priv = private;170 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(priv->substream);171 u8 *pcm_buff = priv->pcm_buff;172 u8 *src_buff = (u8 *)data;173 unsigned int old_pos = priv->pos;174 size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream);175 size_t period_size = snd_pcm_lib_period_bytes(priv->substream);176 size_t cur_size, src_size = size;177 snd_pcm_format_t format = priv->substream->runtime->format;178 179 if (format == SNDRV_PCM_FORMAT_S16_LE)180 src_size >>= 1;181 cur_size = src_size;182 183 dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n",184 __func__, &pcm_buff[priv->pos], priv->pos, src_size);185 186 if ((priv->pos + src_size) > buff_size) {187 if (format == SNDRV_PCM_FORMAT_S16_LE)188 stm32_memcpy_32to16(&pcm_buff[priv->pos], src_buff,189 buff_size - priv->pos);190 else191 memcpy(&pcm_buff[priv->pos], src_buff,192 buff_size - priv->pos);193 cur_size -= buff_size - priv->pos;194 priv->pos = 0;195 }196 197 if (format == SNDRV_PCM_FORMAT_S16_LE)198 stm32_memcpy_32to16(&pcm_buff[priv->pos],199 &src_buff[src_size - cur_size], cur_size);200 else201 memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size],202 cur_size);203 204 priv->pos = (priv->pos + cur_size) % buff_size;205 206 if (cur_size != src_size || (old_pos && (old_pos % period_size < size)))207 snd_pcm_period_elapsed(priv->substream);208 209 return 0;210}211 212static int stm32_adfsdm_trigger(struct snd_soc_component *component,213 struct snd_pcm_substream *substream, int cmd)214{215 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);216 struct stm32_adfsdm_priv *priv =217 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));218 219 switch (cmd) {220 case SNDRV_PCM_TRIGGER_START:221 case SNDRV_PCM_TRIGGER_RESUME:222 priv->pos = 0;223 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev,224 stm32_afsdm_pcm_cb, priv);225 case SNDRV_PCM_TRIGGER_SUSPEND:226 case SNDRV_PCM_TRIGGER_STOP:227 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev);228 }229 230 return -EINVAL;231}232 233static int stm32_adfsdm_pcm_open(struct snd_soc_component *component,234 struct snd_pcm_substream *substream)235{236 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);237 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));238 int ret;239 240 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw);241 if (!ret)242 priv->substream = substream;243 244 return ret;245}246 247static int stm32_adfsdm_pcm_close(struct snd_soc_component *component,248 struct snd_pcm_substream *substream)249{250 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);251 struct stm32_adfsdm_priv *priv =252 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));253 254 priv->substream = NULL;255 256 return 0;257}258 259static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer(260 struct snd_soc_component *component,261 struct snd_pcm_substream *substream)262{263 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);264 struct stm32_adfsdm_priv *priv =265 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));266 267 return bytes_to_frames(substream->runtime, priv->pos);268}269 270static int stm32_adfsdm_pcm_hw_params(struct snd_soc_component *component,271 struct snd_pcm_substream *substream,272 struct snd_pcm_hw_params *params)273{274 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);275 struct stm32_adfsdm_priv *priv =276 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));277 278 priv->pcm_buff = substream->runtime->dma_area;279 280 return iio_channel_cb_set_buffer_watermark(priv->iio_cb,281 params_period_size(params));282}283 284static int stm32_adfsdm_pcm_new(struct snd_soc_component *component,285 struct snd_soc_pcm_runtime *rtd)286{287 struct snd_pcm *pcm = rtd->pcm;288 struct stm32_adfsdm_priv *priv =289 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));290 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE;291 292 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,293 priv->dev, size, size);294 return 0;295}296 297static int stm32_adfsdm_dummy_cb(const void *data, void *private)298{299 /*300 * This dummy callback is requested by iio_channel_get_all_cb() API,301 * but the stm32_dfsdm_get_buff_cb() API is used instead, to optimize302 * DMA transfers.303 */304 return 0;305}306 307static void stm32_adfsdm_cleanup(void *data)308{309 iio_channel_release_all_cb(data);310}311 312static struct snd_soc_component_driver stm32_adfsdm_soc_platform = {313 .open = stm32_adfsdm_pcm_open,314 .close = stm32_adfsdm_pcm_close,315 .hw_params = stm32_adfsdm_pcm_hw_params,316 .trigger = stm32_adfsdm_trigger,317 .pointer = stm32_adfsdm_pcm_pointer,318 .pcm_construct = stm32_adfsdm_pcm_new,319};320 321static const struct of_device_id stm32_adfsdm_of_match[] = {322 {.compatible = "st,stm32h7-dfsdm-dai"},323 {}324};325MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match);326 327static int stm32_adfsdm_probe(struct platform_device *pdev)328{329 struct stm32_adfsdm_priv *priv;330 struct snd_soc_component *component;331 int ret;332 333 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);334 if (!priv)335 return -ENOMEM;336 337 priv->dev = &pdev->dev;338 priv->dai_drv = stm32_adfsdm_dai;339 mutex_init(&priv->lock);340 341 dev_set_drvdata(&pdev->dev, priv);342 343 ret = devm_snd_soc_register_component(&pdev->dev,344 &stm32_adfsdm_dai_component,345 &priv->dai_drv, 1);346 if (ret < 0)347 return ret;348 349 /* Associate iio channel */350 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev);351 if (IS_ERR(priv->iio_ch))352 return PTR_ERR(priv->iio_ch);353 354 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL);355 if (IS_ERR(priv->iio_cb))356 return PTR_ERR(priv->iio_cb);357 358 ret = devm_add_action_or_reset(&pdev->dev, stm32_adfsdm_cleanup, priv->iio_cb);359 if (ret < 0) {360 dev_err(&pdev->dev, "Unable to add action\n");361 return ret;362 }363 364 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL);365 if (!component)366 return -ENOMEM;367 368 ret = snd_soc_component_initialize(component,369 &stm32_adfsdm_soc_platform,370 &pdev->dev);371 if (ret < 0)372 return ret;373#ifdef CONFIG_DEBUG_FS374 component->debugfs_prefix = "pcm";375#endif376 377 ret = snd_soc_add_component(component, NULL, 0);378 if (ret < 0) {379 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n",380 __func__);381 return ret;382 }383 384 pm_runtime_enable(&pdev->dev);385 386 return ret;387}388 389static void stm32_adfsdm_remove(struct platform_device *pdev)390{391 snd_soc_unregister_component(&pdev->dev);392 pm_runtime_disable(&pdev->dev);393}394 395static struct platform_driver stm32_adfsdm_driver = {396 .driver = {397 .name = STM32_ADFSDM_DRV_NAME,398 .of_match_table = stm32_adfsdm_of_match,399 },400 .probe = stm32_adfsdm_probe,401 .remove = stm32_adfsdm_remove,402};403 404module_platform_driver(stm32_adfsdm_driver);405 406MODULE_DESCRIPTION("stm32 DFSDM DAI driver");407MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");408MODULE_LICENSE("GPL v2");409MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME);410