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 #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 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 .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_SIZE 58 }; 59 60 static 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 73 static 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 else 99 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n", 100 __func__, ret); 101 } 102 103 out: 104 mutex_unlock(&priv->lock); 105 106 return ret; 107 } 108 109 static 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 } 130 131 static 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 }; 136 137 static 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 }; 149 150 static const struct snd_soc_component_driver stm32_adfsdm_dai_component = { 151 .name = "stm32_dfsdm_audio", 152 .legacy_dai_naming = 1, 153 }; 154 155 static 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 } 166 167 static 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 = asoc_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 else 191 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 else 201 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 } 211 212 static 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 = asoc_substream_to_rtd(substream); 216 struct stm32_adfsdm_priv *priv = 217 snd_soc_dai_get_drvdata(asoc_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 } 232 233 static int stm32_adfsdm_pcm_open(struct snd_soc_component *component, 234 struct snd_pcm_substream *substream) 235 { 236 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 237 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(asoc_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 } 246 247 static int stm32_adfsdm_pcm_close(struct snd_soc_component *component, 248 struct snd_pcm_substream *substream) 249 { 250 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 251 struct stm32_adfsdm_priv *priv = 252 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 253 254 priv->substream = NULL; 255 256 return 0; 257 } 258 259 static 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 = asoc_substream_to_rtd(substream); 264 struct stm32_adfsdm_priv *priv = 265 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 266 267 return bytes_to_frames(substream->runtime, priv->pos); 268 } 269 270 static 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 = asoc_substream_to_rtd(substream); 275 struct stm32_adfsdm_priv *priv = 276 snd_soc_dai_get_drvdata(asoc_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 } 283 284 static 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(asoc_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 } 296 297 static 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 optimize 302 * DMA transfers. 303 */ 304 return 0; 305 } 306 307 static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 308 .open = stm32_adfsdm_pcm_open, 309 .close = stm32_adfsdm_pcm_close, 310 .hw_params = stm32_adfsdm_pcm_hw_params, 311 .trigger = stm32_adfsdm_trigger, 312 .pointer = stm32_adfsdm_pcm_pointer, 313 .pcm_construct = stm32_adfsdm_pcm_new, 314 }; 315 316 static const struct of_device_id stm32_adfsdm_of_match[] = { 317 {.compatible = "st,stm32h7-dfsdm-dai"}, 318 {} 319 }; 320 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 321 322 static int stm32_adfsdm_probe(struct platform_device *pdev) 323 { 324 struct stm32_adfsdm_priv *priv; 325 struct snd_soc_component *component; 326 int ret; 327 328 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 329 if (!priv) 330 return -ENOMEM; 331 332 priv->dev = &pdev->dev; 333 priv->dai_drv = stm32_adfsdm_dai; 334 mutex_init(&priv->lock); 335 336 dev_set_drvdata(&pdev->dev, priv); 337 338 pm_runtime_enable(&pdev->dev); 339 340 ret = devm_snd_soc_register_component(&pdev->dev, 341 &stm32_adfsdm_dai_component, 342 &priv->dai_drv, 1); 343 if (ret < 0) 344 return ret; 345 346 /* Associate iio channel */ 347 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 348 if (IS_ERR(priv->iio_ch)) 349 return PTR_ERR(priv->iio_ch); 350 351 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL); 352 if (IS_ERR(priv->iio_cb)) 353 return PTR_ERR(priv->iio_cb); 354 355 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL); 356 if (!component) 357 return -ENOMEM; 358 359 ret = snd_soc_component_initialize(component, 360 &stm32_adfsdm_soc_platform, 361 &pdev->dev); 362 if (ret < 0) 363 return ret; 364 #ifdef CONFIG_DEBUG_FS 365 component->debugfs_prefix = "pcm"; 366 #endif 367 368 ret = snd_soc_add_component(component, NULL, 0); 369 if (ret < 0) 370 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n", 371 __func__); 372 373 return ret; 374 } 375 376 static int stm32_adfsdm_remove(struct platform_device *pdev) 377 { 378 snd_soc_unregister_component(&pdev->dev); 379 pm_runtime_disable(&pdev->dev); 380 381 return 0; 382 } 383 384 static struct platform_driver stm32_adfsdm_driver = { 385 .driver = { 386 .name = STM32_ADFSDM_DRV_NAME, 387 .of_match_table = stm32_adfsdm_of_match, 388 }, 389 .probe = stm32_adfsdm_probe, 390 .remove = stm32_adfsdm_remove, 391 }; 392 393 module_platform_driver(stm32_adfsdm_driver); 394 395 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 396 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 397 MODULE_LICENSE("GPL v2"); 398 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 399