1 /* 2 * Copyright (C) 2013, Analog Devices Inc. 3 * Author: Lars-Peter Clausen <lars@metafoo.de> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License as published by the 7 * Free Software Foundation; either version 2 of the License, or (at your 8 * option) any later version. 9 * 10 * You should have received a copy of the GNU General Public License along 11 * with this program; if not, write to the Free Software Foundation, Inc., 12 * 675 Mass Ave, Cambridge, MA 02139, USA. 13 * 14 */ 15 #include <linux/module.h> 16 #include <linux/init.h> 17 #include <linux/dmaengine.h> 18 #include <linux/slab.h> 19 #include <sound/pcm.h> 20 #include <sound/pcm_params.h> 21 #include <sound/soc.h> 22 #include <linux/dma-mapping.h> 23 #include <linux/of.h> 24 25 #include <sound/dmaengine_pcm.h> 26 27 struct dmaengine_pcm { 28 struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1]; 29 const struct snd_dmaengine_pcm_config *config; 30 struct snd_soc_platform platform; 31 unsigned int flags; 32 }; 33 34 static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p) 35 { 36 return container_of(p, struct dmaengine_pcm, platform); 37 } 38 39 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm, 40 struct snd_pcm_substream *substream) 41 { 42 if (!pcm->chan[substream->stream]) 43 return NULL; 44 45 return pcm->chan[substream->stream]->device->dev; 46 } 47 48 /** 49 * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback 50 * @substream: PCM substream 51 * @params: hw_params 52 * @slave_config: DMA slave config to prepare 53 * 54 * This function can be used as a generic prepare_slave_config callback for 55 * platforms which make use of the snd_dmaengine_dai_dma_data struct for their 56 * DAI DMA data. Internally the function will first call 57 * snd_hwparams_to_dma_slave_config to fill in the slave config based on the 58 * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the 59 * remaining fields based on the DAI DMA data. 60 */ 61 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream, 62 struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config) 63 { 64 struct snd_soc_pcm_runtime *rtd = substream->private_data; 65 struct snd_dmaengine_dai_dma_data *dma_data; 66 int ret; 67 68 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 69 70 ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config); 71 if (ret) 72 return ret; 73 74 snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data, 75 slave_config); 76 77 return 0; 78 } 79 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config); 80 81 static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream, 82 struct snd_pcm_hw_params *params) 83 { 84 struct snd_soc_pcm_runtime *rtd = substream->private_data; 85 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); 86 struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream); 87 int (*prepare_slave_config)(struct snd_pcm_substream *substream, 88 struct snd_pcm_hw_params *params, 89 struct dma_slave_config *slave_config); 90 struct dma_slave_config slave_config; 91 int ret; 92 93 memset(&slave_config, 0, sizeof(slave_config)); 94 95 if (!pcm->config) 96 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; 97 else 98 prepare_slave_config = pcm->config->prepare_slave_config; 99 100 if (prepare_slave_config) { 101 ret = prepare_slave_config(substream, params, &slave_config); 102 if (ret) 103 return ret; 104 105 ret = dmaengine_slave_config(chan, &slave_config); 106 if (ret) 107 return ret; 108 } 109 110 return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 111 } 112 113 static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream) 114 { 115 struct snd_soc_pcm_runtime *rtd = substream->private_data; 116 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); 117 struct device *dma_dev = dmaengine_dma_dev(pcm, substream); 118 struct dma_chan *chan = pcm->chan[substream->stream]; 119 struct snd_dmaengine_dai_dma_data *dma_data; 120 struct dma_slave_caps dma_caps; 121 struct snd_pcm_hardware hw; 122 int ret; 123 124 if (pcm->config && pcm->config->pcm_hardware) 125 return snd_soc_set_runtime_hwparams(substream, 126 pcm->config->pcm_hardware); 127 128 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 129 130 memset(&hw, 0, sizeof(hw)); 131 hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 132 SNDRV_PCM_INFO_INTERLEAVED; 133 hw.periods_min = 2; 134 hw.periods_max = UINT_MAX; 135 hw.period_bytes_min = 256; 136 hw.period_bytes_max = dma_get_max_seg_size(dma_dev); 137 hw.buffer_bytes_max = SIZE_MAX; 138 hw.fifo_size = dma_data->fifo_size; 139 140 ret = dma_get_slave_caps(chan, &dma_caps); 141 if (ret == 0) { 142 if (dma_caps.cmd_pause) 143 hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME; 144 } 145 146 return snd_soc_set_runtime_hwparams(substream, &hw); 147 } 148 149 static int dmaengine_pcm_open(struct snd_pcm_substream *substream) 150 { 151 struct snd_soc_pcm_runtime *rtd = substream->private_data; 152 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); 153 struct dma_chan *chan = pcm->chan[substream->stream]; 154 int ret; 155 156 ret = dmaengine_pcm_set_runtime_hwparams(substream); 157 if (ret) 158 return ret; 159 160 return snd_dmaengine_pcm_open(substream, chan); 161 } 162 163 static void dmaengine_pcm_free(struct snd_pcm *pcm) 164 { 165 snd_pcm_lib_preallocate_free_for_all(pcm); 166 } 167 168 static struct dma_chan *dmaengine_pcm_compat_request_channel( 169 struct snd_soc_pcm_runtime *rtd, 170 struct snd_pcm_substream *substream) 171 { 172 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); 173 struct snd_dmaengine_dai_dma_data *dma_data; 174 175 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 176 177 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0]) 178 return pcm->chan[0]; 179 180 if (pcm->config->compat_request_channel) 181 return pcm->config->compat_request_channel(rtd, substream); 182 183 return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_fn, 184 dma_data->filter_data); 185 } 186 187 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd) 188 { 189 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); 190 const struct snd_dmaengine_pcm_config *config = pcm->config; 191 struct device *dev = rtd->platform->dev; 192 struct snd_dmaengine_dai_dma_data *dma_data; 193 struct snd_pcm_substream *substream; 194 size_t prealloc_buffer_size; 195 size_t max_buffer_size; 196 unsigned int i; 197 int ret; 198 199 if (config && config->prealloc_buffer_size) { 200 prealloc_buffer_size = config->prealloc_buffer_size; 201 max_buffer_size = config->pcm_hardware->buffer_bytes_max; 202 } else { 203 prealloc_buffer_size = 512 * 1024; 204 max_buffer_size = SIZE_MAX; 205 } 206 207 208 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) { 209 substream = rtd->pcm->streams[i].substream; 210 if (!substream) 211 continue; 212 213 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 214 215 if (!pcm->chan[i] && 216 (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) 217 pcm->chan[i] = dma_request_slave_channel(dev, 218 dma_data->chan_name); 219 220 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) { 221 pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd, 222 substream); 223 } 224 225 if (!pcm->chan[i]) { 226 dev_err(rtd->platform->dev, 227 "Missing dma channel for stream: %d\n", i); 228 ret = -EINVAL; 229 goto err_free; 230 } 231 232 ret = snd_pcm_lib_preallocate_pages(substream, 233 SNDRV_DMA_TYPE_DEV_IRAM, 234 dmaengine_dma_dev(pcm, substream), 235 prealloc_buffer_size, 236 max_buffer_size); 237 if (ret) 238 goto err_free; 239 } 240 241 return 0; 242 243 err_free: 244 dmaengine_pcm_free(rtd->pcm); 245 return ret; 246 } 247 248 static const struct snd_pcm_ops dmaengine_pcm_ops = { 249 .open = dmaengine_pcm_open, 250 .close = snd_dmaengine_pcm_close, 251 .ioctl = snd_pcm_lib_ioctl, 252 .hw_params = dmaengine_pcm_hw_params, 253 .hw_free = snd_pcm_lib_free_pages, 254 .trigger = snd_dmaengine_pcm_trigger, 255 .pointer = snd_dmaengine_pcm_pointer, 256 }; 257 258 static const struct snd_soc_platform_driver dmaengine_pcm_platform = { 259 .ops = &dmaengine_pcm_ops, 260 .pcm_new = dmaengine_pcm_new, 261 .pcm_free = dmaengine_pcm_free, 262 .probe_order = SND_SOC_COMP_ORDER_LATE, 263 }; 264 265 static const struct snd_pcm_ops dmaengine_no_residue_pcm_ops = { 266 .open = dmaengine_pcm_open, 267 .close = snd_dmaengine_pcm_close, 268 .ioctl = snd_pcm_lib_ioctl, 269 .hw_params = dmaengine_pcm_hw_params, 270 .hw_free = snd_pcm_lib_free_pages, 271 .trigger = snd_dmaengine_pcm_trigger, 272 .pointer = snd_dmaengine_pcm_pointer_no_residue, 273 }; 274 275 static const struct snd_soc_platform_driver dmaengine_no_residue_pcm_platform = { 276 .ops = &dmaengine_no_residue_pcm_ops, 277 .pcm_new = dmaengine_pcm_new, 278 .pcm_free = dmaengine_pcm_free, 279 .probe_order = SND_SOC_COMP_ORDER_LATE, 280 }; 281 282 static const char * const dmaengine_pcm_dma_channel_names[] = { 283 [SNDRV_PCM_STREAM_PLAYBACK] = "tx", 284 [SNDRV_PCM_STREAM_CAPTURE] = "rx", 285 }; 286 287 static void dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm, 288 struct device *dev) 289 { 290 unsigned int i; 291 292 if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT | 293 SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) || 294 !dev->of_node) 295 return; 296 297 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) { 298 pcm->chan[0] = dma_request_slave_channel(dev, "rx-tx"); 299 pcm->chan[1] = pcm->chan[0]; 300 } else { 301 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) { 302 pcm->chan[i] = dma_request_slave_channel(dev, 303 dmaengine_pcm_dma_channel_names[i]); 304 } 305 } 306 } 307 308 static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm) 309 { 310 unsigned int i; 311 312 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; 313 i++) { 314 if (!pcm->chan[i]) 315 continue; 316 dma_release_channel(pcm->chan[i]); 317 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) 318 break; 319 } 320 } 321 322 /** 323 * snd_dmaengine_pcm_register - Register a dmaengine based PCM device 324 * @dev: The parent device for the PCM device 325 * @config: Platform specific PCM configuration 326 * @flags: Platform specific quirks 327 */ 328 int snd_dmaengine_pcm_register(struct device *dev, 329 const struct snd_dmaengine_pcm_config *config, unsigned int flags) 330 { 331 struct dmaengine_pcm *pcm; 332 int ret; 333 334 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL); 335 if (!pcm) 336 return -ENOMEM; 337 338 pcm->config = config; 339 pcm->flags = flags; 340 341 dmaengine_pcm_request_chan_of(pcm, dev); 342 343 if (flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE) 344 ret = snd_soc_add_platform(dev, &pcm->platform, 345 &dmaengine_no_residue_pcm_platform); 346 else 347 ret = snd_soc_add_platform(dev, &pcm->platform, 348 &dmaengine_pcm_platform); 349 if (ret) 350 goto err_free_dma; 351 352 return 0; 353 354 err_free_dma: 355 dmaengine_pcm_release_chan(pcm); 356 kfree(pcm); 357 return ret; 358 } 359 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register); 360 361 /** 362 * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device 363 * @dev: Parent device the PCM was register with 364 * 365 * Removes a dmaengine based PCM device previously registered with 366 * snd_dmaengine_pcm_register. 367 */ 368 void snd_dmaengine_pcm_unregister(struct device *dev) 369 { 370 struct snd_soc_platform *platform; 371 struct dmaengine_pcm *pcm; 372 373 platform = snd_soc_lookup_platform(dev); 374 if (!platform) 375 return; 376 377 pcm = soc_platform_to_pcm(platform); 378 379 snd_soc_remove_platform(platform); 380 dmaengine_pcm_release_chan(pcm); 381 kfree(pcm); 382 } 383 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister); 384 385 MODULE_LICENSE("GPL"); 386