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 guard(mutex)(&priv->lock); 66 if (priv->iio_active) { 67 iio_channel_stop_all_cb(priv->iio_cb); 68 priv->iio_active = false; 69 } 70 } 71 72 static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream, 73 struct snd_soc_dai *dai) 74 { 75 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 76 int ret; 77 78 guard(mutex)(&priv->lock); 79 if (priv->iio_active) { 80 iio_channel_stop_all_cb(priv->iio_cb); 81 priv->iio_active = false; 82 } 83 84 ret = iio_write_channel_attribute(priv->iio_ch, 85 substream->runtime->rate, 0, 86 IIO_CHAN_INFO_SAMP_FREQ); 87 if (ret < 0) { 88 dev_err(dai->dev, "%s: Failed to set %d sampling rate\n", 89 __func__, substream->runtime->rate); 90 return ret; 91 } 92 93 if (!priv->iio_active) { 94 ret = iio_channel_start_all_cb(priv->iio_cb); 95 if (!ret) 96 priv->iio_active = true; 97 else 98 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n", 99 __func__, ret); 100 } 101 102 return ret; 103 } 104 105 static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id, 106 unsigned int freq, int dir) 107 { 108 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 109 ssize_t size; 110 char str_freq[10]; 111 112 dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq); 113 114 /* Set IIO frequency if CODEC is master as clock comes from SPI_IN */ 115 116 snprintf(str_freq, sizeof(str_freq), "%u\n", freq); 117 size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq", 118 str_freq, sizeof(str_freq)); 119 if (size != sizeof(str_freq)) { 120 dev_err(dai->dev, "%s: Failed to set SPI clock\n", 121 __func__); 122 return -EINVAL; 123 } 124 return 0; 125 } 126 127 static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = { 128 .shutdown = stm32_adfsdm_shutdown, 129 .prepare = stm32_adfsdm_dai_prepare, 130 .set_sysclk = stm32_adfsdm_set_sysclk, 131 }; 132 133 static const struct snd_soc_dai_driver stm32_adfsdm_dai = { 134 .capture = { 135 .channels_min = 1, 136 .channels_max = 1, 137 .formats = SNDRV_PCM_FMTBIT_S16_LE | 138 SNDRV_PCM_FMTBIT_S32_LE, 139 .rates = SNDRV_PCM_RATE_CONTINUOUS, 140 .rate_min = 8000, 141 .rate_max = 192000, 142 }, 143 .ops = &stm32_adfsdm_dai_ops, 144 }; 145 146 static const struct snd_soc_component_driver stm32_adfsdm_dai_component = { 147 .name = "stm32_dfsdm_audio", 148 .legacy_dai_naming = 1, 149 }; 150 151 static void stm32_memcpy_32to16(void *dest, const void *src, size_t n) 152 { 153 unsigned int i = 0; 154 u16 *d = (u16 *)dest, *s = (u16 *)src; 155 156 s++; 157 for (i = n >> 1; i > 0; i--) { 158 *d++ = *s++; 159 s++; 160 } 161 } 162 163 static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private) 164 { 165 struct stm32_adfsdm_priv *priv = private; 166 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(priv->substream); 167 u8 *pcm_buff = priv->pcm_buff; 168 u8 *src_buff = (u8 *)data; 169 unsigned int old_pos = priv->pos; 170 size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream); 171 size_t period_size = snd_pcm_lib_period_bytes(priv->substream); 172 size_t cur_size, src_size = size; 173 snd_pcm_format_t format = priv->substream->runtime->format; 174 175 if (format == SNDRV_PCM_FORMAT_S16_LE) 176 src_size >>= 1; 177 cur_size = src_size; 178 179 dev_dbg(rtd->dev, "%s: buff_add :%p, pos = %d, size = %zu\n", 180 __func__, &pcm_buff[priv->pos], priv->pos, src_size); 181 182 if ((priv->pos + src_size) > buff_size) { 183 if (format == SNDRV_PCM_FORMAT_S16_LE) 184 stm32_memcpy_32to16(&pcm_buff[priv->pos], src_buff, 185 buff_size - priv->pos); 186 else 187 memcpy(&pcm_buff[priv->pos], src_buff, 188 buff_size - priv->pos); 189 cur_size -= buff_size - priv->pos; 190 priv->pos = 0; 191 } 192 193 if (format == SNDRV_PCM_FORMAT_S16_LE) 194 stm32_memcpy_32to16(&pcm_buff[priv->pos], 195 &src_buff[src_size - cur_size], cur_size); 196 else 197 memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size], 198 cur_size); 199 200 priv->pos = (priv->pos + cur_size) % buff_size; 201 202 if (cur_size != src_size || (old_pos && (old_pos % period_size < size))) 203 snd_pcm_period_elapsed(priv->substream); 204 205 return 0; 206 } 207 208 static int stm32_adfsdm_trigger(struct snd_soc_component *component, 209 struct snd_pcm_substream *substream, int cmd) 210 { 211 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); 212 struct stm32_adfsdm_priv *priv = 213 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 214 215 switch (cmd) { 216 case SNDRV_PCM_TRIGGER_START: 217 case SNDRV_PCM_TRIGGER_RESUME: 218 priv->pos = 0; 219 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev, 220 stm32_afsdm_pcm_cb, priv); 221 case SNDRV_PCM_TRIGGER_SUSPEND: 222 case SNDRV_PCM_TRIGGER_STOP: 223 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev); 224 } 225 226 return -EINVAL; 227 } 228 229 static int stm32_adfsdm_pcm_open(struct snd_soc_component *component, 230 struct snd_pcm_substream *substream) 231 { 232 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); 233 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 234 int ret; 235 236 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw); 237 if (!ret) 238 priv->substream = substream; 239 240 return ret; 241 } 242 243 static int stm32_adfsdm_pcm_close(struct snd_soc_component *component, 244 struct snd_pcm_substream *substream) 245 { 246 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); 247 struct stm32_adfsdm_priv *priv = 248 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 249 250 priv->substream = NULL; 251 252 return 0; 253 } 254 255 static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer( 256 struct snd_soc_component *component, 257 struct snd_pcm_substream *substream) 258 { 259 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); 260 struct stm32_adfsdm_priv *priv = 261 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 262 263 return bytes_to_frames(substream->runtime, priv->pos); 264 } 265 266 static int stm32_adfsdm_pcm_hw_params(struct snd_soc_component *component, 267 struct snd_pcm_substream *substream, 268 struct snd_pcm_hw_params *params) 269 { 270 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); 271 struct stm32_adfsdm_priv *priv = 272 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 273 274 priv->pcm_buff = substream->runtime->dma_area; 275 276 return iio_channel_cb_set_buffer_watermark(priv->iio_cb, 277 params_period_size(params)); 278 } 279 280 static int stm32_adfsdm_pcm_new(struct snd_soc_component *component, 281 struct snd_soc_pcm_runtime *rtd) 282 { 283 struct snd_pcm *pcm = rtd->pcm; 284 struct stm32_adfsdm_priv *priv = 285 snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0)); 286 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE; 287 288 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, 289 priv->dev, size, size); 290 return 0; 291 } 292 293 static int stm32_adfsdm_dummy_cb(const void *data, void *private) 294 { 295 /* 296 * This dummy callback is requested by iio_channel_get_all_cb() API, 297 * but the stm32_dfsdm_get_buff_cb() API is used instead, to optimize 298 * DMA transfers. 299 */ 300 return 0; 301 } 302 303 static void stm32_adfsdm_cleanup(void *data) 304 { 305 iio_channel_release_all_cb(data); 306 } 307 308 static const struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 309 .open = stm32_adfsdm_pcm_open, 310 .close = stm32_adfsdm_pcm_close, 311 .hw_params = stm32_adfsdm_pcm_hw_params, 312 .trigger = stm32_adfsdm_trigger, 313 .pointer = stm32_adfsdm_pcm_pointer, 314 .pcm_new = stm32_adfsdm_pcm_new, 315 .debugfs_prefix = "pcm", 316 }; 317 318 static const struct of_device_id stm32_adfsdm_of_match[] = { 319 {.compatible = "st,stm32h7-dfsdm-dai"}, 320 {} 321 }; 322 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 323 324 static int stm32_adfsdm_probe(struct platform_device *pdev) 325 { 326 struct stm32_adfsdm_priv *priv; 327 int ret; 328 329 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 330 if (!priv) 331 return -ENOMEM; 332 333 priv->dev = &pdev->dev; 334 priv->dai_drv = stm32_adfsdm_dai; 335 mutex_init(&priv->lock); 336 337 dev_set_drvdata(&pdev->dev, priv); 338 339 ret = devm_snd_soc_register_component(&pdev->dev, 340 &stm32_adfsdm_dai_component, 341 &priv->dai_drv, 1); 342 if (ret < 0) 343 return ret; 344 345 /* Associate iio channel */ 346 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 347 if (IS_ERR(priv->iio_ch)) 348 return PTR_ERR(priv->iio_ch); 349 350 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL); 351 if (IS_ERR(priv->iio_cb)) 352 return PTR_ERR(priv->iio_cb); 353 354 ret = devm_add_action_or_reset(&pdev->dev, stm32_adfsdm_cleanup, priv->iio_cb); 355 if (ret < 0) { 356 dev_err(&pdev->dev, "Unable to add action\n"); 357 return ret; 358 } 359 360 ret = devm_snd_soc_register_component(&pdev->dev, 361 &stm32_adfsdm_soc_platform, 362 NULL, 0); 363 if (ret < 0) 364 return ret; 365 366 pm_runtime_enable(&pdev->dev); 367 368 return ret; 369 } 370 371 static void stm32_adfsdm_remove(struct platform_device *pdev) 372 { 373 snd_soc_unregister_component(&pdev->dev); 374 pm_runtime_disable(&pdev->dev); 375 } 376 377 static struct platform_driver stm32_adfsdm_driver = { 378 .driver = { 379 .name = STM32_ADFSDM_DRV_NAME, 380 .of_match_table = stm32_adfsdm_of_match, 381 }, 382 .probe = stm32_adfsdm_probe, 383 .remove = stm32_adfsdm_remove, 384 }; 385 386 module_platform_driver(stm32_adfsdm_driver); 387 388 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 389 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 390 MODULE_LICENSE("GPL v2"); 391 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 392 MODULE_IMPORT_NS("IIO_CONSUMER"); 393