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/platform_device.h> 13 #include <linux/slab.h> 14 15 #include <linux/iio/iio.h> 16 #include <linux/iio/consumer.h> 17 #include <linux/iio/adc/stm32-dfsdm-adc.h> 18 19 #include <sound/pcm.h> 20 #include <sound/soc.h> 21 22 #define STM32_ADFSDM_DRV_NAME "stm32-adfsdm" 23 24 #define DFSDM_MAX_PERIOD_SIZE (PAGE_SIZE / 2) 25 #define DFSDM_MAX_PERIODS 6 26 27 struct stm32_adfsdm_priv { 28 struct snd_soc_dai_driver dai_drv; 29 struct snd_pcm_substream *substream; 30 struct device *dev; 31 32 /* IIO */ 33 struct iio_channel *iio_ch; 34 struct iio_cb_buffer *iio_cb; 35 bool iio_active; 36 37 /* PCM buffer */ 38 unsigned char *pcm_buff; 39 unsigned int pos; 40 }; 41 42 static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = { 43 .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | 44 SNDRV_PCM_INFO_PAUSE, 45 .formats = SNDRV_PCM_FMTBIT_S32_LE, 46 47 .rate_min = 8000, 48 .rate_max = 32000, 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 if (priv->iio_active) { 66 iio_channel_stop_all_cb(priv->iio_cb); 67 priv->iio_active = false; 68 } 69 } 70 71 static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream, 72 struct snd_soc_dai *dai) 73 { 74 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 75 int ret; 76 77 ret = iio_write_channel_attribute(priv->iio_ch, 78 substream->runtime->rate, 0, 79 IIO_CHAN_INFO_SAMP_FREQ); 80 if (ret < 0) { 81 dev_err(dai->dev, "%s: Failed to set %d sampling rate\n", 82 __func__, substream->runtime->rate); 83 return ret; 84 } 85 86 if (!priv->iio_active) { 87 ret = iio_channel_start_all_cb(priv->iio_cb); 88 if (!ret) 89 priv->iio_active = true; 90 else 91 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n", 92 __func__, ret); 93 } 94 95 return ret; 96 } 97 98 static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id, 99 unsigned int freq, int dir) 100 { 101 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); 102 ssize_t size; 103 char str_freq[10]; 104 105 dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq); 106 107 /* Set IIO frequency if CODEC is master as clock comes from SPI_IN */ 108 109 snprintf(str_freq, sizeof(str_freq), "%d\n", freq); 110 size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq", 111 str_freq, sizeof(str_freq)); 112 if (size != sizeof(str_freq)) { 113 dev_err(dai->dev, "%s: Failed to set SPI clock\n", 114 __func__); 115 return -EINVAL; 116 } 117 return 0; 118 } 119 120 static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = { 121 .shutdown = stm32_adfsdm_shutdown, 122 .prepare = stm32_adfsdm_dai_prepare, 123 .set_sysclk = stm32_adfsdm_set_sysclk, 124 }; 125 126 static const struct snd_soc_dai_driver stm32_adfsdm_dai = { 127 .capture = { 128 .channels_min = 1, 129 .channels_max = 1, 130 .formats = SNDRV_PCM_FMTBIT_S32_LE, 131 .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 | 132 SNDRV_PCM_RATE_32000), 133 }, 134 .ops = &stm32_adfsdm_dai_ops, 135 }; 136 137 static const struct snd_soc_component_driver stm32_adfsdm_dai_component = { 138 .name = "stm32_dfsdm_audio", 139 }; 140 141 static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private) 142 { 143 struct stm32_adfsdm_priv *priv = private; 144 struct snd_soc_pcm_runtime *rtd = priv->substream->private_data; 145 u8 *pcm_buff = priv->pcm_buff; 146 u8 *src_buff = (u8 *)data; 147 unsigned int buff_size = snd_pcm_lib_buffer_bytes(priv->substream); 148 unsigned int period_size = snd_pcm_lib_period_bytes(priv->substream); 149 unsigned int old_pos = priv->pos; 150 unsigned int cur_size = size; 151 152 dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n", 153 __func__, &pcm_buff[priv->pos], priv->pos, size); 154 155 if ((priv->pos + size) > buff_size) { 156 memcpy(&pcm_buff[priv->pos], src_buff, buff_size - priv->pos); 157 cur_size -= buff_size - priv->pos; 158 priv->pos = 0; 159 } 160 161 memcpy(&pcm_buff[priv->pos], &src_buff[size - cur_size], cur_size); 162 priv->pos = (priv->pos + cur_size) % buff_size; 163 164 if (cur_size != size || (old_pos && (old_pos % period_size < size))) 165 snd_pcm_period_elapsed(priv->substream); 166 167 return 0; 168 } 169 170 static int stm32_adfsdm_trigger(struct snd_pcm_substream *substream, int cmd) 171 { 172 struct snd_soc_pcm_runtime *rtd = substream->private_data; 173 struct stm32_adfsdm_priv *priv = 174 snd_soc_dai_get_drvdata(rtd->cpu_dai); 175 176 switch (cmd) { 177 case SNDRV_PCM_TRIGGER_START: 178 case SNDRV_PCM_TRIGGER_RESUME: 179 priv->pos = 0; 180 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev, 181 stm32_afsdm_pcm_cb, priv); 182 case SNDRV_PCM_TRIGGER_SUSPEND: 183 case SNDRV_PCM_TRIGGER_STOP: 184 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev); 185 } 186 187 return -EINVAL; 188 } 189 190 static int stm32_adfsdm_pcm_open(struct snd_pcm_substream *substream) 191 { 192 struct snd_soc_pcm_runtime *rtd = substream->private_data; 193 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); 194 int ret; 195 196 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw); 197 if (!ret) 198 priv->substream = substream; 199 200 return ret; 201 } 202 203 static int stm32_adfsdm_pcm_close(struct snd_pcm_substream *substream) 204 { 205 struct snd_soc_pcm_runtime *rtd = substream->private_data; 206 struct stm32_adfsdm_priv *priv = 207 snd_soc_dai_get_drvdata(rtd->cpu_dai); 208 209 snd_pcm_lib_free_pages(substream); 210 priv->substream = NULL; 211 212 return 0; 213 } 214 215 static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer( 216 struct snd_pcm_substream *substream) 217 { 218 struct snd_soc_pcm_runtime *rtd = substream->private_data; 219 struct stm32_adfsdm_priv *priv = 220 snd_soc_dai_get_drvdata(rtd->cpu_dai); 221 222 return bytes_to_frames(substream->runtime, priv->pos); 223 } 224 225 static int stm32_adfsdm_pcm_hw_params(struct snd_pcm_substream *substream, 226 struct snd_pcm_hw_params *params) 227 { 228 struct snd_soc_pcm_runtime *rtd = substream->private_data; 229 struct stm32_adfsdm_priv *priv = 230 snd_soc_dai_get_drvdata(rtd->cpu_dai); 231 int ret; 232 233 ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 234 if (ret < 0) 235 return ret; 236 priv->pcm_buff = substream->runtime->dma_area; 237 238 return iio_channel_cb_set_buffer_watermark(priv->iio_cb, 239 params_period_size(params)); 240 } 241 242 static int stm32_adfsdm_pcm_hw_free(struct snd_pcm_substream *substream) 243 { 244 snd_pcm_lib_free_pages(substream); 245 246 return 0; 247 } 248 249 static struct snd_pcm_ops stm32_adfsdm_pcm_ops = { 250 .open = stm32_adfsdm_pcm_open, 251 .close = stm32_adfsdm_pcm_close, 252 .hw_params = stm32_adfsdm_pcm_hw_params, 253 .hw_free = stm32_adfsdm_pcm_hw_free, 254 .trigger = stm32_adfsdm_trigger, 255 .pointer = stm32_adfsdm_pcm_pointer, 256 }; 257 258 static int stm32_adfsdm_pcm_new(struct snd_soc_pcm_runtime *rtd) 259 { 260 struct snd_pcm *pcm = rtd->pcm; 261 struct stm32_adfsdm_priv *priv = 262 snd_soc_dai_get_drvdata(rtd->cpu_dai); 263 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE; 264 265 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, 266 priv->dev, size, size); 267 return 0; 268 } 269 270 static void stm32_adfsdm_pcm_free(struct snd_pcm *pcm) 271 { 272 struct snd_pcm_substream *substream; 273 274 substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; 275 if (substream) 276 snd_pcm_lib_preallocate_free_for_all(pcm); 277 } 278 279 static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { 280 .ops = &stm32_adfsdm_pcm_ops, 281 .pcm_new = stm32_adfsdm_pcm_new, 282 .pcm_free = stm32_adfsdm_pcm_free, 283 }; 284 285 static const struct of_device_id stm32_adfsdm_of_match[] = { 286 {.compatible = "st,stm32h7-dfsdm-dai"}, 287 {} 288 }; 289 MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match); 290 291 static int stm32_adfsdm_probe(struct platform_device *pdev) 292 { 293 struct stm32_adfsdm_priv *priv; 294 int ret; 295 296 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 297 if (!priv) 298 return -ENOMEM; 299 300 priv->dev = &pdev->dev; 301 priv->dai_drv = stm32_adfsdm_dai; 302 303 dev_set_drvdata(&pdev->dev, priv); 304 305 ret = devm_snd_soc_register_component(&pdev->dev, 306 &stm32_adfsdm_dai_component, 307 &priv->dai_drv, 1); 308 if (ret < 0) 309 return ret; 310 311 /* Associate iio channel */ 312 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev); 313 if (IS_ERR(priv->iio_ch)) 314 return PTR_ERR(priv->iio_ch); 315 316 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, NULL, NULL); 317 if (IS_ERR(priv->iio_cb)) 318 return PTR_ERR(priv->iio_cb); 319 320 ret = devm_snd_soc_register_component(&pdev->dev, 321 &stm32_adfsdm_soc_platform, 322 NULL, 0); 323 if (ret < 0) 324 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n", 325 __func__); 326 327 return ret; 328 } 329 330 static struct platform_driver stm32_adfsdm_driver = { 331 .driver = { 332 .name = STM32_ADFSDM_DRV_NAME, 333 .of_match_table = stm32_adfsdm_of_match, 334 }, 335 .probe = stm32_adfsdm_probe, 336 }; 337 338 module_platform_driver(stm32_adfsdm_driver); 339 340 MODULE_DESCRIPTION("stm32 DFSDM DAI driver"); 341 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 342 MODULE_LICENSE("GPL v2"); 343 MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME); 344