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_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_S32_LE, 145 .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 | 146 SNDRV_PCM_RATE_32000), 147 }, 148 .ops = &stm32_adfsdm_dai_ops, 149 }; 150 151 static const struct snd_soc_component_driver stm32_adfsdm_dai_component = { 152 .name = "stm32_dfsdm_audio", 153 }; 154 155 static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private) 156 { 157 struct stm32_adfsdm_priv *priv = private; 158 struct snd_soc_pcm_runtime *rtd = priv->substream->private_data; 159 u8 *pcm_buff = priv->pcm_buff; 160 u8 *src_buff = (u8 *)data; 161 unsigned int buff_size = snd_pcm_lib_buffer_bytes(priv->substream); 162 unsigned int period_size = snd_pcm_lib_period_bytes(priv->substream); 163 unsigned int old_pos = priv->pos; 164 unsigned int cur_size = size; 165 166 dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n", 167 __func__, &pcm_buff[priv->pos], priv->pos, size); 168 169 if ((priv->pos + size) > buff_size) { 170 memcpy(&pcm_buff[priv->pos], src_buff, buff_size - priv->pos); 171 cur_size -= buff_size - priv->pos; 172 priv->pos = 0; 173 } 174 175 memcpy(&pcm_buff[priv->pos], &src_buff[size - cur_size], cur_size); 176 priv->pos = (priv->pos + cur_size) % buff_size; 177 178 if (cur_size != size || (old_pos && (old_pos % period_size < size))) 179 snd_pcm_period_elapsed(priv->substream); 180 181 return 0; 182 } 183 184 static int stm32_adfsdm_trigger(struct snd_pcm_substream *substream, int cmd) 185 { 186 struct snd_soc_pcm_runtime *rtd = substream->private_data; 187 struct stm32_adfsdm_priv *priv = 188 snd_soc_dai_get_drvdata(rtd->cpu_dai); 189 190 switch (cmd) { 191 case SNDRV_PCM_TRIGGER_START: 192 case SNDRV_PCM_TRIGGER_RESUME: 193 priv->pos = 0; 194 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev, 195 stm32_afsdm_pcm_cb, priv); 196 case SNDRV_PCM_TRIGGER_SUSPEND: 197 case SNDRV_PCM_TRIGGER_STOP: 198 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev); 199 } 200 201 return -EINVAL; 202 } 203 204 static int stm32_adfsdm_pcm_open(struct snd_pcm_substream *substream) 205 { 206 struct snd_soc_pcm_runtime *rtd = substream->private_data; 207 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); 208 int ret; 209 210 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw); 211 if (!ret) 212 priv->substream = substream; 213 214 return ret; 215 } 216 217 static int stm32_adfsdm_pcm_close(struct snd_pcm_substream *substream) 218 { 219 struct snd_soc_pcm_runtime *rtd = substream->private_data; 220 struct stm32_adfsdm_priv *priv = 221 snd_soc_dai_get_drvdata(rtd->cpu_dai); 222 223 snd_pcm_lib_free_pages(substream); 224 priv->substream = NULL; 225 226 return 0; 227 } 228 229 static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer( 230 struct snd_pcm_substream *substream) 231 { 232 struct snd_soc_pcm_runtime *rtd = substream->private_data; 233 struct stm32_adfsdm_priv *priv = 234 snd_soc_dai_get_drvdata(rtd->cpu_dai); 235 236 return bytes_to_frames(substream->runtime, priv->pos); 237 } 238 239 static int stm32_adfsdm_pcm_hw_params(struct snd_pcm_substream *substream, 240 struct snd_pcm_hw_params *params) 241 { 242 struct snd_soc_pcm_runtime *rtd = substream->private_data; 243 struct stm32_adfsdm_priv *priv = 244 snd_soc_dai_get_drvdata(rtd->cpu_dai); 245 int ret; 246 247 ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 248 if (ret < 0) 249 return ret; 250 priv->pcm_buff = substream->runtime->dma_area; 251 252 return iio_channel_cb_set_buffer_watermark(priv->iio_cb, 253 params_period_size(params)); 254 } 255 256 static int stm32_adfsdm_pcm_hw_free(struct snd_pcm_substream *substream) 257 { 258 snd_pcm_lib_free_pages(substream); 259 260 return 0; 261 } 262 263 static struct snd_pcm_ops stm32_adfsdm_pcm_ops = { 264 .open = stm32_adfsdm_pcm_open, 265 .close = stm32_adfsdm_pcm_close, 266 .hw_params = stm32_adfsdm_pcm_hw_params, 267 .hw_free = stm32_adfsdm_pcm_hw_free, 268 .trigger = stm32_adfsdm_trigger, 269 .pointer = stm32_adfsdm_pcm_pointer, 270 }; 271 272 static int stm32_adfsdm_pcm_new(struct snd_soc_pcm_runtime *rtd) 273 { 274 struct snd_pcm *pcm = rtd->pcm; 275 struct stm32_adfsdm_priv *priv = 276 snd_soc_dai_get_drvdata(rtd->cpu_dai); 277 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE; 278 279 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, 280 priv->dev, size, size); 281 return 0; 282 } 283 284 static void stm32_adfsdm_pcm_free(struct snd_pcm *pcm) 285 { 286 struct snd_pcm_substream *substream; 287 288 substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; 289 if (substream) 290 snd_pcm_lib_preallocate_free_for_all(pcm); 291 } 292 293 static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 294 .ops = &stm32_adfsdm_pcm_ops, 295 .pcm_new = stm32_adfsdm_pcm_new, 296 .pcm_free = stm32_adfsdm_pcm_free, 297 }; 298 299 static const struct of_device_id stm32_adfsdm_of_match[] = { 300 {.compatible = "st,stm32h7-dfsdm-dai"}, 301 {} 302 }; 303 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 304 305 static int stm32_adfsdm_probe(struct platform_device *pdev) 306 { 307 struct stm32_adfsdm_priv *priv; 308 struct snd_soc_component *component; 309 int ret; 310 311 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 312 if (!priv) 313 return -ENOMEM; 314 315 priv->dev = &pdev->dev; 316 priv->dai_drv = stm32_adfsdm_dai; 317 mutex_init(&priv->lock); 318 319 dev_set_drvdata(&pdev->dev, priv); 320 321 ret = devm_snd_soc_register_component(&pdev->dev, 322 &stm32_adfsdm_dai_component, 323 &priv->dai_drv, 1); 324 if (ret < 0) 325 return ret; 326 327 /* Associate iio channel */ 328 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 329 if (IS_ERR(priv->iio_ch)) 330 return PTR_ERR(priv->iio_ch); 331 332 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, NULL, NULL); 333 if (IS_ERR(priv->iio_cb)) 334 return PTR_ERR(priv->iio_cb); 335 336 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL); 337 if (!component) 338 return -ENOMEM; 339 #ifdef CONFIG_DEBUG_FS 340 component->debugfs_prefix = "pcm"; 341 #endif 342 343 ret = snd_soc_add_component(&pdev->dev, component, 344 &stm32_adfsdm_soc_platform, NULL, 0); 345 if (ret < 0) 346 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n", 347 __func__); 348 349 return ret; 350 } 351 352 static int stm32_adfsdm_remove(struct platform_device *pdev) 353 { 354 snd_soc_unregister_component(&pdev->dev); 355 356 return 0; 357 } 358 359 static struct platform_driver stm32_adfsdm_driver = { 360 .driver = { 361 .name = STM32_ADFSDM_DRV_NAME, 362 .of_match_table = stm32_adfsdm_of_match, 363 }, 364 .probe = stm32_adfsdm_probe, 365 .remove = stm32_adfsdm_remove, 366 }; 367 368 module_platform_driver(stm32_adfsdm_driver); 369 370 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 371 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 372 MODULE_LICENSE("GPL v2"); 373 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 374