497 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*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 Systems11 */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_config45 * @substream: PCM substream46 * @params: hw_params47 * @slave_config: DMA slave config48 *49 * This function can be used to initialize a dma_slave_config from a substream50 * and hw_params in a dmaengine based PCM driver implementation.51 *52 * Return: zero if successful, or a negative error code53 */54int 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 else73 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}87EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);88 89/**90 * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config91 * using DAI DMA data.92 * @substream: PCM substream93 * @dma_data: DAI DMA data94 * @slave_config: DMA slave configuration95 *96 * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width97 * fields of the DMA slave config from the same fields of the DAI DMA98 * data struct. The src and dst fields will be initialized depending on the99 * direction of the substream. If the substream is a playback stream the dst100 * fields will be initialized, if it is a capture stream the src fields will be101 * initialized. The {dst,src}_addr_width field will only be initialized if the102 * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of103 * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If104 * both conditions are met the latter takes priority.105 */106void 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}132EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);133 134static void dmaengine_pcm_dma_complete(void *arg)135{136 unsigned int new_pos;137 struct snd_pcm_substream *substream = arg;138 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);139 140 new_pos = prtd->pos + snd_pcm_lib_period_bytes(substream);141 if (new_pos >= snd_pcm_lib_buffer_bytes(substream))142 new_pos = 0;143 prtd->pos = new_pos;144 145 snd_pcm_period_elapsed(substream);146}147 148static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)149{150 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);151 struct dma_chan *chan = prtd->dma_chan;152 struct dma_async_tx_descriptor *desc;153 enum dma_transfer_direction direction;154 unsigned long flags = DMA_CTRL_ACK;155 156 direction = snd_pcm_substream_to_dma_direction(substream);157 158 if (!substream->runtime->no_period_wakeup)159 flags |= DMA_PREP_INTERRUPT;160 161 prtd->pos = 0;162 desc = dmaengine_prep_dma_cyclic(chan,163 substream->runtime->dma_addr,164 snd_pcm_lib_buffer_bytes(substream),165 snd_pcm_lib_period_bytes(substream), direction, flags);166 167 if (!desc)168 return -ENOMEM;169 170 desc->callback = dmaengine_pcm_dma_complete;171 desc->callback_param = substream;172 prtd->cookie = dmaengine_submit(desc);173 174 return 0;175}176 177/**178 * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation179 * @substream: PCM substream180 * @cmd: Trigger command181 *182 * This function can be used as the PCM trigger callback for dmaengine based PCM183 * driver implementations.184 *185 * Return: 0 on success, a negative error code otherwise186 */187int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)188{189 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);190 struct snd_pcm_runtime *runtime = substream->runtime;191 int ret;192 193 switch (cmd) {194 case SNDRV_PCM_TRIGGER_START:195 ret = dmaengine_pcm_prepare_and_submit(substream);196 if (ret)197 return ret;198 dma_async_issue_pending(prtd->dma_chan);199 break;200 case SNDRV_PCM_TRIGGER_RESUME:201 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:202 dmaengine_resume(prtd->dma_chan);203 break;204 case SNDRV_PCM_TRIGGER_SUSPEND:205 if (runtime->info & SNDRV_PCM_INFO_PAUSE)206 dmaengine_pause(prtd->dma_chan);207 else208 dmaengine_terminate_async(prtd->dma_chan);209 break;210 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:211 dmaengine_pause(prtd->dma_chan);212 break;213 case SNDRV_PCM_TRIGGER_STOP:214 dmaengine_terminate_async(prtd->dma_chan);215 break;216 default:217 return -EINVAL;218 }219 220 return 0;221}222EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);223 224/**225 * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation226 * @substream: PCM substream227 *228 * This function is deprecated and should not be used by new drivers, as its229 * results may be unreliable.230 *231 * Return: PCM position in frames232 */233snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)234{235 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);236 return bytes_to_frames(substream->runtime, prtd->pos);237}238EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);239 240/**241 * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation242 * @substream: PCM substream243 *244 * This function can be used as the PCM pointer callback for dmaengine based PCM245 * driver implementations.246 *247 * Return: PCM position in frames248 */249snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)250{251 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);252 struct snd_pcm_runtime *runtime = substream->runtime;253 struct dma_tx_state state;254 enum dma_status status;255 unsigned int buf_size;256 unsigned int pos = 0;257 258 status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);259 if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {260 buf_size = snd_pcm_lib_buffer_bytes(substream);261 if (state.residue > 0 && state.residue <= buf_size)262 pos = buf_size - state.residue;263 264 runtime->delay = bytes_to_frames(runtime,265 state.in_flight_bytes);266 }267 268 return bytes_to_frames(runtime, pos);269}270EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);271 272/**273 * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM274 * @filter_fn: Filter function used to request the DMA channel275 * @filter_data: Data passed to the DMA filter function276 *277 * This function request a DMA channel for usage with dmaengine PCM.278 *279 * Return: NULL or the requested DMA channel280 */281struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,282 void *filter_data)283{284 dma_cap_mask_t mask;285 286 dma_cap_zero(mask);287 dma_cap_set(DMA_SLAVE, mask);288 dma_cap_set(DMA_CYCLIC, mask);289 290 return dma_request_channel(mask, filter_fn, filter_data);291}292EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);293 294/**295 * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream296 * @substream: PCM substream297 * @chan: DMA channel to use for data transfers298 *299 * The function should usually be called from the pcm open callback. Note that300 * this function will use private_data field of the substream's runtime. So it301 * is not available to your pcm driver implementation.302 *303 * Return: 0 on success, a negative error code otherwise304 */305int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,306 struct dma_chan *chan)307{308 struct dmaengine_pcm_runtime_data *prtd;309 int ret;310 311 if (!chan)312 return -ENXIO;313 314 ret = snd_pcm_hw_constraint_integer(substream->runtime,315 SNDRV_PCM_HW_PARAM_PERIODS);316 if (ret < 0)317 return ret;318 319 prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);320 if (!prtd)321 return -ENOMEM;322 323 prtd->dma_chan = chan;324 325 substream->runtime->private_data = prtd;326 327 return 0;328}329EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);330 331/**332 * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel333 * @substream: PCM substream334 * @filter_fn: Filter function used to request the DMA channel335 * @filter_data: Data passed to the DMA filter function336 *337 * This function will request a DMA channel using the passed filter function and338 * data. The function should usually be called from the pcm open callback. Note339 * that this function will use private_data field of the substream's runtime. So340 * it is not available to your pcm driver implementation.341 *342 * Return: 0 on success, a negative error code otherwise343 */344int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,345 dma_filter_fn filter_fn, void *filter_data)346{347 return snd_dmaengine_pcm_open(substream,348 snd_dmaengine_pcm_request_channel(filter_fn, filter_data));349}350EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);351 352int snd_dmaengine_pcm_sync_stop(struct snd_pcm_substream *substream)353{354 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);355 struct dma_tx_state state;356 enum dma_status status;357 358 status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);359 if (status != DMA_PAUSED)360 dmaengine_synchronize(prtd->dma_chan);361 362 return 0;363}364EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_sync_stop);365 366static void __snd_dmaengine_pcm_close(struct snd_pcm_substream *substream,367 bool release_channel)368{369 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);370 struct dma_tx_state state;371 enum dma_status status;372 373 status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);374 if (status == DMA_PAUSED)375 dmaengine_terminate_async(prtd->dma_chan);376 377 dmaengine_synchronize(prtd->dma_chan);378 if (release_channel)379 dma_release_channel(prtd->dma_chan);380 kfree(prtd);381}382 383/**384 * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream385 * @substream: PCM substream386 *387 * Return: 0 on success, a negative error code otherwise388 */389int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)390{391 __snd_dmaengine_pcm_close(substream, false);392 return 0;393}394EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);395 396/**397 * snd_dmaengine_pcm_close_release_chan - Close a dmaengine based PCM398 * substream and release channel399 * @substream: PCM substream400 *401 * Releases the DMA channel associated with the PCM substream.402 *403 * Return: zero if successful, or a negative error code404 */405int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)406{407 __snd_dmaengine_pcm_close(substream, true);408 return 0;409}410EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);411 412/**413 * snd_dmaengine_pcm_refine_runtime_hwparams - Refine runtime hw params414 * @substream: PCM substream415 * @dma_data: DAI DMA data416 * @hw: PCM hw params417 * @chan: DMA channel to use for data transfers418 *419 * This function will query DMA capability, then refine the pcm hardware420 * parameters.421 *422 * Return: 0 on success, a negative error code otherwise423 */424int snd_dmaengine_pcm_refine_runtime_hwparams(425 struct snd_pcm_substream *substream,426 struct snd_dmaengine_dai_dma_data *dma_data,427 struct snd_pcm_hardware *hw,428 struct dma_chan *chan)429{430 struct dma_slave_caps dma_caps;431 u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |432 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |433 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);434 snd_pcm_format_t i;435 int ret = 0;436 437 if (!hw || !chan || !dma_data)438 return -EINVAL;439 440 ret = dma_get_slave_caps(chan, &dma_caps);441 if (ret == 0) {442 if (dma_caps.cmd_pause && dma_caps.cmd_resume)443 hw->info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;444 if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)445 hw->info |= SNDRV_PCM_INFO_BATCH;446 447 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)448 addr_widths = dma_caps.dst_addr_widths;449 else450 addr_widths = dma_caps.src_addr_widths;451 }452 453 /*454 * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep455 * hw.formats set to 0, meaning no restrictions are in place.456 * In this case it's the responsibility of the DAI driver to457 * provide the supported format information.458 */459 if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))460 /*461 * Prepare formats mask for valid/allowed sample types. If the462 * dma does not have support for the given physical word size,463 * it needs to be masked out so user space can not use the464 * format which produces corrupted audio.465 * In case the dma driver does not implement the slave_caps the466 * default assumption is that it supports 1, 2 and 4 bytes467 * widths.468 */469 pcm_for_each_format(i) {470 int bits = snd_pcm_format_physical_width(i);471 472 /*473 * Enable only samples with DMA supported physical474 * widths475 */476 switch (bits) {477 case 8:478 case 16:479 case 24:480 case 32:481 case 64:482 if (addr_widths & (1 << (bits / 8)))483 hw->formats |= pcm_format_to_bits(i);484 break;485 default:486 /* Unsupported types */487 break;488 }489 }490 491 return ret;492}493EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_refine_runtime_hwparams);494 495MODULE_DESCRIPTION("PCM dmaengine helper APIs");496MODULE_LICENSE("GPL");497