1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2012, Analog Devices Inc. 4 * Author: Lars-Peter Clausen <lars@metafoo.de> 5 * 6 * Based on: 7 * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de> 8 * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc. 9 * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> 10 * Copyright (C) 2006 Applied Data Systems 11 */ 12 #include <linux/module.h> 13 #include <linux/init.h> 14 #include <linux/dmaengine.h> 15 #include <linux/slab.h> 16 #include <sound/pcm.h> 17 #include <sound/pcm_params.h> 18 #include <sound/soc.h> 19 20 #include <sound/dmaengine_pcm.h> 21 22 struct dmaengine_pcm_runtime_data { 23 struct dma_chan *dma_chan; 24 dma_cookie_t cookie; 25 26 unsigned int pos; 27 }; 28 29 static inline struct dmaengine_pcm_runtime_data *substream_to_prtd( 30 const struct snd_pcm_substream *substream) 31 { 32 return substream->runtime->private_data; 33 } 34 35 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream) 36 { 37 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 38 39 return prtd->dma_chan; 40 } 41 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan); 42 43 /** 44 * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config 45 * @substream: PCM substream 46 * @params: hw_params 47 * @slave_config: DMA slave config 48 * 49 * This function can be used to initialize a dma_slave_config from a substream 50 * and hw_params in a dmaengine based PCM driver implementation. 51 * 52 * Return: zero if successful, or a negative error code 53 */ 54 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream, 55 const struct snd_pcm_hw_params *params, 56 struct dma_slave_config *slave_config) 57 { 58 enum dma_slave_buswidth buswidth; 59 int bits; 60 61 bits = params_physical_width(params); 62 if (bits < 8 || bits > 64) 63 return -EINVAL; 64 else if (bits == 8) 65 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; 66 else if (bits == 16) 67 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; 68 else if (bits == 24) 69 buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES; 70 else if (bits <= 32) 71 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; 72 else 73 buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES; 74 75 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 76 slave_config->direction = DMA_MEM_TO_DEV; 77 slave_config->dst_addr_width = buswidth; 78 } else { 79 slave_config->direction = DMA_DEV_TO_MEM; 80 slave_config->src_addr_width = buswidth; 81 } 82 83 slave_config->device_fc = false; 84 85 return 0; 86 } 87 EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config); 88 89 /** 90 * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config 91 * using DAI DMA data. 92 * @substream: PCM substream 93 * @dma_data: DAI DMA data 94 * @slave_config: DMA slave configuration 95 * 96 * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width 97 * fields of the DMA slave config from the same fields of the DAI DMA 98 * data struct. The src and dst fields will be initialized depending on the 99 * direction of the substream. If the substream is a playback stream the dst 100 * fields will be initialized, if it is a capture stream the src fields will be 101 * initialized. The {dst,src}_addr_width field will only be initialized if the 102 * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of 103 * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If 104 * both conditions are met the latter takes priority. 105 */ 106 void snd_dmaengine_pcm_set_config_from_dai_data( 107 const struct snd_pcm_substream *substream, 108 const struct snd_dmaengine_dai_dma_data *dma_data, 109 struct dma_slave_config *slave_config) 110 { 111 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 112 slave_config->dst_addr = dma_data->addr; 113 slave_config->dst_maxburst = dma_data->maxburst; 114 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK) 115 slave_config->dst_addr_width = 116 DMA_SLAVE_BUSWIDTH_UNDEFINED; 117 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED) 118 slave_config->dst_addr_width = dma_data->addr_width; 119 } else { 120 slave_config->src_addr = dma_data->addr; 121 slave_config->src_maxburst = dma_data->maxburst; 122 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK) 123 slave_config->src_addr_width = 124 DMA_SLAVE_BUSWIDTH_UNDEFINED; 125 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED) 126 slave_config->src_addr_width = dma_data->addr_width; 127 } 128 129 slave_config->peripheral_config = dma_data->peripheral_config; 130 slave_config->peripheral_size = dma_data->peripheral_size; 131 } 132 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data); 133 134 static void dmaengine_pcm_dma_complete(void *arg) 135 { 136 struct snd_pcm_substream *substream = arg; 137 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 138 139 prtd->pos += snd_pcm_lib_period_bytes(substream); 140 if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream)) 141 prtd->pos = 0; 142 143 snd_pcm_period_elapsed(substream); 144 } 145 146 static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream) 147 { 148 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 149 struct dma_chan *chan = prtd->dma_chan; 150 struct dma_async_tx_descriptor *desc; 151 enum dma_transfer_direction direction; 152 unsigned long flags = DMA_CTRL_ACK; 153 154 direction = snd_pcm_substream_to_dma_direction(substream); 155 156 if (!substream->runtime->no_period_wakeup) 157 flags |= DMA_PREP_INTERRUPT; 158 159 prtd->pos = 0; 160 desc = dmaengine_prep_dma_cyclic(chan, 161 substream->runtime->dma_addr, 162 snd_pcm_lib_buffer_bytes(substream), 163 snd_pcm_lib_period_bytes(substream), direction, flags); 164 165 if (!desc) 166 return -ENOMEM; 167 168 desc->callback = dmaengine_pcm_dma_complete; 169 desc->callback_param = substream; 170 prtd->cookie = dmaengine_submit(desc); 171 172 return 0; 173 } 174 175 /** 176 * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation 177 * @substream: PCM substream 178 * @cmd: Trigger command 179 * 180 * This function can be used as the PCM trigger callback for dmaengine based PCM 181 * driver implementations. 182 * 183 * Return: 0 on success, a negative error code otherwise 184 */ 185 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 186 { 187 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 188 struct snd_pcm_runtime *runtime = substream->runtime; 189 int ret; 190 191 switch (cmd) { 192 case SNDRV_PCM_TRIGGER_START: 193 ret = dmaengine_pcm_prepare_and_submit(substream); 194 if (ret) 195 return ret; 196 dma_async_issue_pending(prtd->dma_chan); 197 break; 198 case SNDRV_PCM_TRIGGER_RESUME: 199 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 200 dmaengine_resume(prtd->dma_chan); 201 break; 202 case SNDRV_PCM_TRIGGER_SUSPEND: 203 if (runtime->info & SNDRV_PCM_INFO_PAUSE) 204 dmaengine_pause(prtd->dma_chan); 205 else 206 dmaengine_terminate_async(prtd->dma_chan); 207 break; 208 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 209 dmaengine_pause(prtd->dma_chan); 210 break; 211 case SNDRV_PCM_TRIGGER_STOP: 212 dmaengine_terminate_async(prtd->dma_chan); 213 break; 214 default: 215 return -EINVAL; 216 } 217 218 return 0; 219 } 220 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger); 221 222 /** 223 * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation 224 * @substream: PCM substream 225 * 226 * This function is deprecated and should not be used by new drivers, as its 227 * results may be unreliable. 228 * 229 * Return: PCM position in frames 230 */ 231 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream) 232 { 233 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 234 return bytes_to_frames(substream->runtime, prtd->pos); 235 } 236 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue); 237 238 /** 239 * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation 240 * @substream: PCM substream 241 * 242 * This function can be used as the PCM pointer callback for dmaengine based PCM 243 * driver implementations. 244 * 245 * Return: PCM position in frames 246 */ 247 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream) 248 { 249 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 250 struct snd_pcm_runtime *runtime = substream->runtime; 251 struct dma_tx_state state; 252 enum dma_status status; 253 unsigned int buf_size; 254 unsigned int pos = 0; 255 256 status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state); 257 if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) { 258 buf_size = snd_pcm_lib_buffer_bytes(substream); 259 if (state.residue > 0 && state.residue <= buf_size) 260 pos = buf_size - state.residue; 261 262 runtime->delay = bytes_to_frames(runtime, 263 state.in_flight_bytes); 264 } 265 266 return bytes_to_frames(runtime, pos); 267 } 268 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer); 269 270 /** 271 * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM 272 * @filter_fn: Filter function used to request the DMA channel 273 * @filter_data: Data passed to the DMA filter function 274 * 275 * This function request a DMA channel for usage with dmaengine PCM. 276 * 277 * Return: NULL or the requested DMA channel 278 */ 279 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn, 280 void *filter_data) 281 { 282 dma_cap_mask_t mask; 283 284 dma_cap_zero(mask); 285 dma_cap_set(DMA_SLAVE, mask); 286 dma_cap_set(DMA_CYCLIC, mask); 287 288 return dma_request_channel(mask, filter_fn, filter_data); 289 } 290 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel); 291 292 /** 293 * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream 294 * @substream: PCM substream 295 * @chan: DMA channel to use for data transfers 296 * 297 * The function should usually be called from the pcm open callback. Note that 298 * this function will use private_data field of the substream's runtime. So it 299 * is not available to your pcm driver implementation. 300 * 301 * Return: 0 on success, a negative error code otherwise 302 */ 303 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, 304 struct dma_chan *chan) 305 { 306 struct dmaengine_pcm_runtime_data *prtd; 307 int ret; 308 309 if (!chan) 310 return -ENXIO; 311 312 ret = snd_pcm_hw_constraint_integer(substream->runtime, 313 SNDRV_PCM_HW_PARAM_PERIODS); 314 if (ret < 0) 315 return ret; 316 317 prtd = kzalloc(sizeof(*prtd), GFP_KERNEL); 318 if (!prtd) 319 return -ENOMEM; 320 321 prtd->dma_chan = chan; 322 323 substream->runtime->private_data = prtd; 324 325 return 0; 326 } 327 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open); 328 329 /** 330 * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel 331 * @substream: PCM substream 332 * @filter_fn: Filter function used to request the DMA channel 333 * @filter_data: Data passed to the DMA filter function 334 * 335 * This function will request a DMA channel using the passed filter function and 336 * data. The function should usually be called from the pcm open callback. Note 337 * that this function will use private_data field of the substream's runtime. So 338 * it is not available to your pcm driver implementation. 339 * 340 * Return: 0 on success, a negative error code otherwise 341 */ 342 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream, 343 dma_filter_fn filter_fn, void *filter_data) 344 { 345 return snd_dmaengine_pcm_open(substream, 346 snd_dmaengine_pcm_request_channel(filter_fn, filter_data)); 347 } 348 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan); 349 350 /** 351 * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream 352 * @substream: PCM substream 353 * 354 * Return: 0 on success, a negative error code otherwise 355 */ 356 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream) 357 { 358 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 359 360 dmaengine_synchronize(prtd->dma_chan); 361 kfree(prtd); 362 363 return 0; 364 } 365 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close); 366 367 /** 368 * snd_dmaengine_pcm_close_release_chan - Close a dmaengine based PCM 369 * substream and release channel 370 * @substream: PCM substream 371 * 372 * Releases the DMA channel associated with the PCM substream. 373 * 374 * Return: zero if successful, or a negative error code 375 */ 376 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream) 377 { 378 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); 379 380 dmaengine_synchronize(prtd->dma_chan); 381 dma_release_channel(prtd->dma_chan); 382 kfree(prtd); 383 384 return 0; 385 } 386 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan); 387 388 /** 389 * snd_dmaengine_pcm_refine_runtime_hwparams - Refine runtime hw params 390 * @substream: PCM substream 391 * @dma_data: DAI DMA data 392 * @hw: PCM hw params 393 * @chan: DMA channel to use for data transfers 394 * 395 * This function will query DMA capability, then refine the pcm hardware 396 * parameters. 397 * 398 * Return: 0 on success, a negative error code otherwise 399 */ 400 int snd_dmaengine_pcm_refine_runtime_hwparams( 401 struct snd_pcm_substream *substream, 402 struct snd_dmaengine_dai_dma_data *dma_data, 403 struct snd_pcm_hardware *hw, 404 struct dma_chan *chan) 405 { 406 struct dma_slave_caps dma_caps; 407 u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | 408 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | 409 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); 410 snd_pcm_format_t i; 411 int ret = 0; 412 413 if (!hw || !chan || !dma_data) 414 return -EINVAL; 415 416 ret = dma_get_slave_caps(chan, &dma_caps); 417 if (ret == 0) { 418 if (dma_caps.cmd_pause && dma_caps.cmd_resume) 419 hw->info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME; 420 if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT) 421 hw->info |= SNDRV_PCM_INFO_BATCH; 422 423 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 424 addr_widths = dma_caps.dst_addr_widths; 425 else 426 addr_widths = dma_caps.src_addr_widths; 427 } 428 429 /* 430 * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep 431 * hw.formats set to 0, meaning no restrictions are in place. 432 * In this case it's the responsibility of the DAI driver to 433 * provide the supported format information. 434 */ 435 if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)) 436 /* 437 * Prepare formats mask for valid/allowed sample types. If the 438 * dma does not have support for the given physical word size, 439 * it needs to be masked out so user space can not use the 440 * format which produces corrupted audio. 441 * In case the dma driver does not implement the slave_caps the 442 * default assumption is that it supports 1, 2 and 4 bytes 443 * widths. 444 */ 445 pcm_for_each_format(i) { 446 int bits = snd_pcm_format_physical_width(i); 447 448 /* 449 * Enable only samples with DMA supported physical 450 * widths 451 */ 452 switch (bits) { 453 case 8: 454 case 16: 455 case 24: 456 case 32: 457 case 64: 458 if (addr_widths & (1 << (bits / 8))) 459 hw->formats |= pcm_format_to_bits(i); 460 break; 461 default: 462 /* Unsupported types */ 463 break; 464 } 465 } 466 467 return ret; 468 } 469 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_refine_runtime_hwparams); 470 471 MODULE_LICENSE("GPL"); 472