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 stm32_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 >> 1; 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 stm32_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 stm32_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_soc_component *component, 214 struct snd_pcm_substream *substream, int cmd) 215 { 216 struct snd_soc_pcm_runtime *rtd = substream->private_data; 217 struct stm32_adfsdm_priv *priv = 218 snd_soc_dai_get_drvdata(rtd->cpu_dai); 219 220 switch (cmd) { 221 case SNDRV_PCM_TRIGGER_START: 222 case SNDRV_PCM_TRIGGER_RESUME: 223 priv->pos = 0; 224 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev, 225 stm32_afsdm_pcm_cb, priv); 226 case SNDRV_PCM_TRIGGER_SUSPEND: 227 case SNDRV_PCM_TRIGGER_STOP: 228 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev); 229 } 230 231 return -EINVAL; 232 } 233 234 static int stm32_adfsdm_pcm_open(struct snd_soc_component *component, 235 struct snd_pcm_substream *substream) 236 { 237 struct snd_soc_pcm_runtime *rtd = substream->private_data; 238 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); 239 int ret; 240 241 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw); 242 if (!ret) 243 priv->substream = substream; 244 245 return ret; 246 } 247 248 static int stm32_adfsdm_pcm_close(struct snd_soc_component *component, 249 struct snd_pcm_substream *substream) 250 { 251 struct snd_soc_pcm_runtime *rtd = substream->private_data; 252 struct stm32_adfsdm_priv *priv = 253 snd_soc_dai_get_drvdata(rtd->cpu_dai); 254 255 priv->substream = NULL; 256 257 return 0; 258 } 259 260 static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer( 261 struct snd_soc_component *component, 262 struct snd_pcm_substream *substream) 263 { 264 struct snd_soc_pcm_runtime *rtd = substream->private_data; 265 struct stm32_adfsdm_priv *priv = 266 snd_soc_dai_get_drvdata(rtd->cpu_dai); 267 268 return bytes_to_frames(substream->runtime, priv->pos); 269 } 270 271 static int stm32_adfsdm_pcm_hw_params(struct snd_soc_component *component, 272 struct snd_pcm_substream *substream, 273 struct snd_pcm_hw_params *params) 274 { 275 struct snd_soc_pcm_runtime *rtd = substream->private_data; 276 struct stm32_adfsdm_priv *priv = 277 snd_soc_dai_get_drvdata(rtd->cpu_dai); 278 279 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_new(struct snd_soc_component *component, 286 struct snd_soc_pcm_runtime *rtd) 287 { 288 struct snd_pcm *pcm = rtd->pcm; 289 struct stm32_adfsdm_priv *priv = 290 snd_soc_dai_get_drvdata(rtd->cpu_dai); 291 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE; 292 293 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, 294 priv->dev, size, size); 295 return 0; 296 } 297 298 static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 299 .open = stm32_adfsdm_pcm_open, 300 .close = stm32_adfsdm_pcm_close, 301 .hw_params = stm32_adfsdm_pcm_hw_params, 302 .trigger = stm32_adfsdm_trigger, 303 .pointer = stm32_adfsdm_pcm_pointer, 304 .pcm_construct = stm32_adfsdm_pcm_new, 305 }; 306 307 static const struct of_device_id stm32_adfsdm_of_match[] = { 308 {.compatible = "st,stm32h7-dfsdm-dai"}, 309 {} 310 }; 311 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 312 313 static int stm32_adfsdm_probe(struct platform_device *pdev) 314 { 315 struct stm32_adfsdm_priv *priv; 316 struct snd_soc_component *component; 317 int ret; 318 319 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 320 if (!priv) 321 return -ENOMEM; 322 323 priv->dev = &pdev->dev; 324 priv->dai_drv = stm32_adfsdm_dai; 325 mutex_init(&priv->lock); 326 327 dev_set_drvdata(&pdev->dev, priv); 328 329 ret = devm_snd_soc_register_component(&pdev->dev, 330 &stm32_adfsdm_dai_component, 331 &priv->dai_drv, 1); 332 if (ret < 0) 333 return ret; 334 335 /* Associate iio channel */ 336 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 337 if (IS_ERR(priv->iio_ch)) 338 return PTR_ERR(priv->iio_ch); 339 340 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, NULL, NULL); 341 if (IS_ERR(priv->iio_cb)) 342 return PTR_ERR(priv->iio_cb); 343 344 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL); 345 if (!component) 346 return -ENOMEM; 347 #ifdef CONFIG_DEBUG_FS 348 component->debugfs_prefix = "pcm"; 349 #endif 350 351 ret = snd_soc_add_component(&pdev->dev, component, 352 &stm32_adfsdm_soc_platform, NULL, 0); 353 if (ret < 0) 354 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n", 355 __func__); 356 357 return ret; 358 } 359 360 static int stm32_adfsdm_remove(struct platform_device *pdev) 361 { 362 snd_soc_unregister_component(&pdev->dev); 363 364 return 0; 365 } 366 367 static struct platform_driver stm32_adfsdm_driver = { 368 .driver = { 369 .name = STM32_ADFSDM_DRV_NAME, 370 .of_match_table = stm32_adfsdm_of_match, 371 }, 372 .probe = stm32_adfsdm_probe, 373 .remove = stm32_adfsdm_remove, 374 }; 375 376 module_platform_driver(stm32_adfsdm_driver); 377 378 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 379 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 380 MODULE_LICENSE("GPL v2"); 381 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 382