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