1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * This file is part of STM32 DFSDM ASoC DAI driver 4 * 5 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 6 * 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 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 6 27 28 struct 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 45 static 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 .rate_min = 8000, 51 .rate_max = 32000, 52 53 .channels_min = 1, 54 .channels_max = 1, 55 56 .periods_min = 2, 57 .periods_max = DFSDM_MAX_PERIODS, 58 59 .period_bytes_max = DFSDM_MAX_PERIOD_SIZE, 60 .buffer_bytes_max = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE 61 }; 62 63 static void stm32_adfsdm_shutdown(struct snd_pcm_substream *substream, 64 struct snd_soc_dai *dai) 65 { 66 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 67 68 mutex_lock(&priv->lock); 69 if (priv->iio_active) { 70 iio_channel_stop_all_cb(priv->iio_cb); 71 priv->iio_active = false; 72 } 73 mutex_unlock(&priv->lock); 74 } 75 76 static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream, 77 struct snd_soc_dai *dai) 78 { 79 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 80 int ret; 81 82 mutex_lock(&priv->lock); 83 if (priv->iio_active) { 84 iio_channel_stop_all_cb(priv->iio_cb); 85 priv->iio_active = false; 86 } 87 88 ret = iio_write_channel_attribute(priv->iio_ch, 89 substream->runtime->rate, 0, 90 IIO_CHAN_INFO_SAMP_FREQ); 91 if (ret < 0) { 92 dev_err(dai->dev, "%s: Failed to set %d sampling rate\n", 93 __func__, substream->runtime->rate); 94 goto out; 95 } 96 97 if (!priv->iio_active) { 98 ret = iio_channel_start_all_cb(priv->iio_cb); 99 if (!ret) 100 priv->iio_active = true; 101 else 102 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n", 103 __func__, ret); 104 } 105 106 out: 107 mutex_unlock(&priv->lock); 108 109 return ret; 110 } 111 112 static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id, 113 unsigned int freq, int dir) 114 { 115 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 116 ssize_t size; 117 char str_freq[10]; 118 119 dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq); 120 121 /* Set IIO frequency if CODEC is master as clock comes from SPI_IN */ 122 123 snprintf(str_freq, sizeof(str_freq), "%d\n", freq); 124 size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq", 125 str_freq, sizeof(str_freq)); 126 if (size != sizeof(str_freq)) { 127 dev_err(dai->dev, "%s: Failed to set SPI clock\n", 128 __func__); 129 return -EINVAL; 130 } 131 return 0; 132 } 133 134 static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = { 135 .shutdown = stm32_adfsdm_shutdown, 136 .prepare = stm32_adfsdm_dai_prepare, 137 .set_sysclk = stm32_adfsdm_set_sysclk, 138 }; 139 140 static const struct snd_soc_dai_driver stm32_adfsdm_dai = { 141 .capture = { 142 .channels_min = 1, 143 .channels_max = 1, 144 .formats = SNDRV_PCM_FMTBIT_S16_LE | 145 SNDRV_PCM_FMTBIT_S32_LE, 146 .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 | 147 SNDRV_PCM_RATE_32000), 148 }, 149 .ops = &stm32_adfsdm_dai_ops, 150 }; 151 152 static const struct snd_soc_component_driver stm32_adfsdm_dai_component = { 153 .name = "stm32_dfsdm_audio", 154 }; 155 156 static void memcpy_32to16(void *dest, const void *src, size_t n) 157 { 158 unsigned int i = 0; 159 u16 *d = (u16 *)dest, *s = (u16 *)src; 160 161 s++; 162 for (i = n; i > 0; i--) { 163 *d++ = *s++; 164 s++; 165 } 166 } 167 168 static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private) 169 { 170 struct stm32_adfsdm_priv *priv = private; 171 struct snd_soc_pcm_runtime *rtd = priv->substream->private_data; 172 u8 *pcm_buff = priv->pcm_buff; 173 u8 *src_buff = (u8 *)data; 174 unsigned int old_pos = priv->pos; 175 size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream); 176 size_t period_size = snd_pcm_lib_period_bytes(priv->substream); 177 size_t cur_size, src_size = size; 178 snd_pcm_format_t format = priv->substream->runtime->format; 179 180 if (format == SNDRV_PCM_FORMAT_S16_LE) 181 src_size >>= 1; 182 cur_size = src_size; 183 184 dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n", 185 __func__, &pcm_buff[priv->pos], priv->pos, src_size); 186 187 if ((priv->pos + src_size) > buff_size) { 188 if (format == SNDRV_PCM_FORMAT_S16_LE) 189 memcpy_32to16(&pcm_buff[priv->pos], src_buff, 190 buff_size - priv->pos); 191 else 192 memcpy(&pcm_buff[priv->pos], src_buff, 193 buff_size - priv->pos); 194 cur_size -= buff_size - priv->pos; 195 priv->pos = 0; 196 } 197 198 if (format == SNDRV_PCM_FORMAT_S16_LE) 199 memcpy_32to16(&pcm_buff[priv->pos], 200 &src_buff[src_size - cur_size], cur_size); 201 else 202 memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size], 203 cur_size); 204 205 priv->pos = (priv->pos + cur_size) % buff_size; 206 207 if (cur_size != src_size || (old_pos && (old_pos % period_size < size))) 208 snd_pcm_period_elapsed(priv->substream); 209 210 return 0; 211 } 212 213 static int stm32_adfsdm_trigger(struct snd_pcm_substream *substream, int cmd) 214 { 215 struct snd_soc_pcm_runtime *rtd = substream->private_data; 216 struct stm32_adfsdm_priv *priv = 217 snd_soc_dai_get_drvdata(rtd->cpu_dai); 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 } 232 233 static int stm32_adfsdm_pcm_open(struct snd_pcm_substream *substream) 234 { 235 struct snd_soc_pcm_runtime *rtd = substream->private_data; 236 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); 237 int ret; 238 239 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw); 240 if (!ret) 241 priv->substream = substream; 242 243 return ret; 244 } 245 246 static int stm32_adfsdm_pcm_close(struct snd_pcm_substream *substream) 247 { 248 struct snd_soc_pcm_runtime *rtd = substream->private_data; 249 struct stm32_adfsdm_priv *priv = 250 snd_soc_dai_get_drvdata(rtd->cpu_dai); 251 252 snd_pcm_lib_free_pages(substream); 253 priv->substream = NULL; 254 255 return 0; 256 } 257 258 static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer( 259 struct snd_pcm_substream *substream) 260 { 261 struct snd_soc_pcm_runtime *rtd = substream->private_data; 262 struct stm32_adfsdm_priv *priv = 263 snd_soc_dai_get_drvdata(rtd->cpu_dai); 264 265 return bytes_to_frames(substream->runtime, priv->pos); 266 } 267 268 static int stm32_adfsdm_pcm_hw_params(struct snd_pcm_substream *substream, 269 struct snd_pcm_hw_params *params) 270 { 271 struct snd_soc_pcm_runtime *rtd = substream->private_data; 272 struct stm32_adfsdm_priv *priv = 273 snd_soc_dai_get_drvdata(rtd->cpu_dai); 274 int ret; 275 276 ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 277 if (ret < 0) 278 return ret; 279 priv->pcm_buff = substream->runtime->dma_area; 280 281 return iio_channel_cb_set_buffer_watermark(priv->iio_cb, 282 params_period_size(params)); 283 } 284 285 static int stm32_adfsdm_pcm_hw_free(struct snd_pcm_substream *substream) 286 { 287 snd_pcm_lib_free_pages(substream); 288 289 return 0; 290 } 291 292 static struct snd_pcm_ops stm32_adfsdm_pcm_ops = { 293 .open = stm32_adfsdm_pcm_open, 294 .close = stm32_adfsdm_pcm_close, 295 .hw_params = stm32_adfsdm_pcm_hw_params, 296 .hw_free = stm32_adfsdm_pcm_hw_free, 297 .trigger = stm32_adfsdm_trigger, 298 .pointer = stm32_adfsdm_pcm_pointer, 299 }; 300 301 static int stm32_adfsdm_pcm_new(struct snd_soc_pcm_runtime *rtd) 302 { 303 struct snd_pcm *pcm = rtd->pcm; 304 struct stm32_adfsdm_priv *priv = 305 snd_soc_dai_get_drvdata(rtd->cpu_dai); 306 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE; 307 308 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, 309 priv->dev, size, size); 310 return 0; 311 } 312 313 static void stm32_adfsdm_pcm_free(struct snd_pcm *pcm) 314 { 315 struct snd_pcm_substream *substream; 316 317 substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; 318 if (substream) 319 snd_pcm_lib_preallocate_free_for_all(pcm); 320 } 321 322 static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 323 .ops = &stm32_adfsdm_pcm_ops, 324 .pcm_new = stm32_adfsdm_pcm_new, 325 .pcm_free = stm32_adfsdm_pcm_free, 326 }; 327 328 static const struct of_device_id stm32_adfsdm_of_match[] = { 329 {.compatible = "st,stm32h7-dfsdm-dai"}, 330 {} 331 }; 332 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 333 334 static int stm32_adfsdm_probe(struct platform_device *pdev) 335 { 336 struct stm32_adfsdm_priv *priv; 337 struct snd_soc_component *component; 338 int ret; 339 340 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 341 if (!priv) 342 return -ENOMEM; 343 344 priv->dev = &pdev->dev; 345 priv->dai_drv = stm32_adfsdm_dai; 346 mutex_init(&priv->lock); 347 348 dev_set_drvdata(&pdev->dev, priv); 349 350 ret = devm_snd_soc_register_component(&pdev->dev, 351 &stm32_adfsdm_dai_component, 352 &priv->dai_drv, 1); 353 if (ret < 0) 354 return ret; 355 356 /* Associate iio channel */ 357 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 358 if (IS_ERR(priv->iio_ch)) 359 return PTR_ERR(priv->iio_ch); 360 361 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, NULL, NULL); 362 if (IS_ERR(priv->iio_cb)) 363 return PTR_ERR(priv->iio_cb); 364 365 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL); 366 if (!component) 367 return -ENOMEM; 368 #ifdef CONFIG_DEBUG_FS 369 component->debugfs_prefix = "pcm"; 370 #endif 371 372 ret = snd_soc_add_component(&pdev->dev, component, 373 &stm32_adfsdm_soc_platform, NULL, 0); 374 if (ret < 0) 375 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n", 376 __func__); 377 378 return ret; 379 } 380 381 static int stm32_adfsdm_remove(struct platform_device *pdev) 382 { 383 snd_soc_unregister_component(&pdev->dev); 384 385 return 0; 386 } 387 388 static struct platform_driver stm32_adfsdm_driver = { 389 .driver = { 390 .name = STM32_ADFSDM_DRV_NAME, 391 .of_match_table = stm32_adfsdm_of_match, 392 }, 393 .probe = stm32_adfsdm_probe, 394 .remove = stm32_adfsdm_remove, 395 }; 396 397 module_platform_driver(stm32_adfsdm_driver); 398 399 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 400 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 401 MODULE_LICENSE("GPL v2"); 402 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 403