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