1 // SPDX-License-Identifier: GPL-2.0-only 2 // 3 // Freescale MPC5200 PSC DMA 4 // ALSA SoC Platform driver 5 // 6 // Copyright (C) 2008 Secret Lab Technologies Ltd. 7 // Copyright (C) 2009 Jon Smirl, Digispeaker 8 9 #include <linux/module.h> 10 #include <linux/of_device.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/slab.h> 13 #include <linux/of_address.h> 14 #include <linux/of_irq.h> 15 #include <linux/of_platform.h> 16 17 #include <sound/soc.h> 18 19 #include <linux/fsl/bestcomm/bestcomm.h> 20 #include <linux/fsl/bestcomm/gen_bd.h> 21 #include <asm/mpc52xx_psc.h> 22 23 #include "mpc5200_dma.h" 24 25 #define DRV_NAME "mpc5200_dma" 26 27 /* 28 * Interrupt handlers 29 */ 30 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma) 31 { 32 struct psc_dma *psc_dma = _psc_dma; 33 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs; 34 u16 isr; 35 36 isr = in_be16(®s->mpc52xx_psc_isr); 37 38 /* Playback underrun error */ 39 if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP)) 40 psc_dma->stats.underrun_count++; 41 42 /* Capture overrun error */ 43 if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR)) 44 psc_dma->stats.overrun_count++; 45 46 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT); 47 48 return IRQ_HANDLED; 49 } 50 51 /** 52 * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer 53 * @s: pointer to stream private data structure 54 * 55 * Enqueues another audio period buffer into the bestcomm queue. 56 * 57 * Note: The routine must only be called when there is space available in 58 * the queue. Otherwise the enqueue will fail and the audio ring buffer 59 * will get out of sync 60 */ 61 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s) 62 { 63 struct bcom_bd *bd; 64 65 /* Prepare and enqueue the next buffer descriptor */ 66 bd = bcom_prepare_next_buffer(s->bcom_task); 67 bd->status = s->period_bytes; 68 bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes); 69 bcom_submit_next_buffer(s->bcom_task, NULL); 70 71 /* Update for next period */ 72 s->period_next = (s->period_next + 1) % s->runtime->periods; 73 } 74 75 /* Bestcomm DMA irq handler */ 76 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream) 77 { 78 struct psc_dma_stream *s = _psc_dma_stream; 79 80 spin_lock(&s->psc_dma->lock); 81 /* For each finished period, dequeue the completed period buffer 82 * and enqueue a new one in it's place. */ 83 while (bcom_buffer_done(s->bcom_task)) { 84 bcom_retrieve_buffer(s->bcom_task, NULL, NULL); 85 86 s->period_current = (s->period_current+1) % s->runtime->periods; 87 s->period_count++; 88 89 psc_dma_bcom_enqueue_next_buffer(s); 90 } 91 spin_unlock(&s->psc_dma->lock); 92 93 /* If the stream is active, then also inform the PCM middle layer 94 * of the period finished event. */ 95 if (s->active) 96 snd_pcm_period_elapsed(s->stream); 97 98 return IRQ_HANDLED; 99 } 100 101 static int psc_dma_hw_free(struct snd_soc_component *component, 102 struct snd_pcm_substream *substream) 103 { 104 snd_pcm_set_runtime_buffer(substream, NULL); 105 return 0; 106 } 107 108 /** 109 * psc_dma_trigger: start and stop the DMA transfer. 110 * 111 * This function is called by ALSA to start, stop, pause, and resume the DMA 112 * transfer of data. 113 */ 114 static int psc_dma_trigger(struct snd_soc_component *component, 115 struct snd_pcm_substream *substream, int cmd) 116 { 117 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 118 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 119 struct snd_pcm_runtime *runtime = substream->runtime; 120 struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma); 121 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs; 122 u16 imr; 123 unsigned long flags; 124 int i; 125 126 switch (cmd) { 127 case SNDRV_PCM_TRIGGER_START: 128 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n", 129 substream->pstr->stream, runtime->frame_bits, 130 (int)runtime->period_size, runtime->periods); 131 s->period_bytes = frames_to_bytes(runtime, 132 runtime->period_size); 133 s->period_next = 0; 134 s->period_current = 0; 135 s->active = 1; 136 s->period_count = 0; 137 s->runtime = runtime; 138 139 /* Fill up the bestcomm bd queue and enable DMA. 140 * This will begin filling the PSC's fifo. 141 */ 142 spin_lock_irqsave(&psc_dma->lock, flags); 143 144 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 145 bcom_gen_bd_rx_reset(s->bcom_task); 146 else 147 bcom_gen_bd_tx_reset(s->bcom_task); 148 149 for (i = 0; i < runtime->periods; i++) 150 if (!bcom_queue_full(s->bcom_task)) 151 psc_dma_bcom_enqueue_next_buffer(s); 152 153 bcom_enable(s->bcom_task); 154 spin_unlock_irqrestore(&psc_dma->lock, flags); 155 156 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT); 157 158 break; 159 160 case SNDRV_PCM_TRIGGER_STOP: 161 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n", 162 substream->pstr->stream, s->period_count); 163 s->active = 0; 164 165 spin_lock_irqsave(&psc_dma->lock, flags); 166 bcom_disable(s->bcom_task); 167 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 168 bcom_gen_bd_rx_reset(s->bcom_task); 169 else 170 bcom_gen_bd_tx_reset(s->bcom_task); 171 spin_unlock_irqrestore(&psc_dma->lock, flags); 172 173 break; 174 175 default: 176 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n", 177 substream->pstr->stream, cmd); 178 return -EINVAL; 179 } 180 181 /* Update interrupt enable settings */ 182 imr = 0; 183 if (psc_dma->playback.active) 184 imr |= MPC52xx_PSC_IMR_TXEMP; 185 if (psc_dma->capture.active) 186 imr |= MPC52xx_PSC_IMR_ORERR; 187 out_be16(®s->isr_imr.imr, psc_dma->imr | imr); 188 189 return 0; 190 } 191 192 193 /* --------------------------------------------------------------------- 194 * The PSC DMA 'ASoC platform' driver 195 * 196 * Can be referenced by an 'ASoC machine' driver 197 * This driver only deals with the audio bus; it doesn't have any 198 * interaction with the attached codec 199 */ 200 201 static const struct snd_pcm_hardware psc_dma_hardware = { 202 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 203 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | 204 SNDRV_PCM_INFO_BATCH, 205 .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | 206 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE, 207 .period_bytes_max = 1024 * 1024, 208 .period_bytes_min = 32, 209 .periods_min = 2, 210 .periods_max = 256, 211 .buffer_bytes_max = 2 * 1024 * 1024, 212 .fifo_size = 512, 213 }; 214 215 static int psc_dma_open(struct snd_soc_component *component, 216 struct snd_pcm_substream *substream) 217 { 218 struct snd_pcm_runtime *runtime = substream->runtime; 219 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 220 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 221 struct psc_dma_stream *s; 222 int rc; 223 224 dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream); 225 226 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 227 s = &psc_dma->capture; 228 else 229 s = &psc_dma->playback; 230 231 snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware); 232 233 rc = snd_pcm_hw_constraint_integer(runtime, 234 SNDRV_PCM_HW_PARAM_PERIODS); 235 if (rc < 0) { 236 dev_err(substream->pcm->card->dev, "invalid buffer size\n"); 237 return rc; 238 } 239 240 s->stream = substream; 241 return 0; 242 } 243 244 static int psc_dma_close(struct snd_soc_component *component, 245 struct snd_pcm_substream *substream) 246 { 247 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 248 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 249 struct psc_dma_stream *s; 250 251 dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream); 252 253 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 254 s = &psc_dma->capture; 255 else 256 s = &psc_dma->playback; 257 258 if (!psc_dma->playback.active && 259 !psc_dma->capture.active) { 260 261 /* Disable all interrupts and reset the PSC */ 262 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 263 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */ 264 } 265 s->stream = NULL; 266 return 0; 267 } 268 269 static snd_pcm_uframes_t 270 psc_dma_pointer(struct snd_soc_component *component, 271 struct snd_pcm_substream *substream) 272 { 273 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 274 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 275 struct psc_dma_stream *s; 276 dma_addr_t count; 277 278 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 279 s = &psc_dma->capture; 280 else 281 s = &psc_dma->playback; 282 283 count = s->period_current * s->period_bytes; 284 285 return bytes_to_frames(substream->runtime, count); 286 } 287 288 static int psc_dma_hw_params(struct snd_soc_component *component, 289 struct snd_pcm_substream *substream, 290 struct snd_pcm_hw_params *params) 291 { 292 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 293 294 return 0; 295 } 296 297 static int psc_dma_new(struct snd_soc_component *component, 298 struct snd_soc_pcm_runtime *rtd) 299 { 300 struct snd_card *card = rtd->card->snd_card; 301 struct snd_soc_dai *dai = asoc_rtd_to_cpu(rtd, 0); 302 struct snd_pcm *pcm = rtd->pcm; 303 size_t size = psc_dma_hardware.buffer_bytes_max; 304 int rc; 305 306 dev_dbg(component->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n", 307 card, dai, pcm); 308 309 rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 310 if (rc) 311 return rc; 312 313 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 314 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 315 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 316 if (rc) 317 goto playback_alloc_err; 318 } 319 320 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 321 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 322 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer); 323 if (rc) 324 goto capture_alloc_err; 325 } 326 327 return 0; 328 329 capture_alloc_err: 330 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) 331 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 332 333 playback_alloc_err: 334 dev_err(card->dev, "Cannot allocate buffer(s)\n"); 335 336 return -ENOMEM; 337 } 338 339 static void psc_dma_free(struct snd_soc_component *component, 340 struct snd_pcm *pcm) 341 { 342 struct snd_pcm_substream *substream; 343 int stream; 344 345 dev_dbg(component->dev, "psc_dma_free(pcm=%p)\n", pcm); 346 347 for (stream = 0; stream < 2; stream++) { 348 substream = pcm->streams[stream].substream; 349 if (substream) { 350 snd_dma_free_pages(&substream->dma_buffer); 351 substream->dma_buffer.area = NULL; 352 substream->dma_buffer.addr = 0; 353 } 354 } 355 } 356 357 static const struct snd_soc_component_driver mpc5200_audio_dma_component = { 358 .name = DRV_NAME, 359 .open = psc_dma_open, 360 .close = psc_dma_close, 361 .hw_free = psc_dma_hw_free, 362 .pointer = psc_dma_pointer, 363 .trigger = psc_dma_trigger, 364 .hw_params = psc_dma_hw_params, 365 .pcm_construct = psc_dma_new, 366 .pcm_destruct = psc_dma_free, 367 }; 368 369 int mpc5200_audio_dma_create(struct platform_device *op) 370 { 371 phys_addr_t fifo; 372 struct psc_dma *psc_dma; 373 struct resource res; 374 int size, irq, rc; 375 const __be32 *prop; 376 void __iomem *regs; 377 int ret; 378 379 /* Fetch the registers and IRQ of the PSC */ 380 irq = irq_of_parse_and_map(op->dev.of_node, 0); 381 if (of_address_to_resource(op->dev.of_node, 0, &res)) { 382 dev_err(&op->dev, "Missing reg property\n"); 383 return -ENODEV; 384 } 385 regs = ioremap(res.start, resource_size(&res)); 386 if (!regs) { 387 dev_err(&op->dev, "Could not map registers\n"); 388 return -ENODEV; 389 } 390 391 /* Allocate and initialize the driver private data */ 392 psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL); 393 if (!psc_dma) { 394 ret = -ENOMEM; 395 goto out_unmap; 396 } 397 398 /* Get the PSC ID */ 399 prop = of_get_property(op->dev.of_node, "cell-index", &size); 400 if (!prop || size < sizeof *prop) { 401 ret = -ENODEV; 402 goto out_free; 403 } 404 405 spin_lock_init(&psc_dma->lock); 406 mutex_init(&psc_dma->mutex); 407 psc_dma->id = be32_to_cpu(*prop); 408 psc_dma->irq = irq; 409 psc_dma->psc_regs = regs; 410 psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs; 411 psc_dma->dev = &op->dev; 412 psc_dma->playback.psc_dma = psc_dma; 413 psc_dma->capture.psc_dma = psc_dma; 414 snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id); 415 416 /* Find the address of the fifo data registers and setup the 417 * DMA tasks */ 418 fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32); 419 psc_dma->capture.bcom_task = 420 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512); 421 psc_dma->playback.bcom_task = 422 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo); 423 if (!psc_dma->capture.bcom_task || 424 !psc_dma->playback.bcom_task) { 425 dev_err(&op->dev, "Could not allocate bestcomm tasks\n"); 426 ret = -ENODEV; 427 goto out_free; 428 } 429 430 /* Disable all interrupts and reset the PSC */ 431 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 432 /* reset receiver */ 433 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX); 434 /* reset transmitter */ 435 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX); 436 /* reset error */ 437 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT); 438 /* reset mode */ 439 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1); 440 441 /* Set up mode register; 442 * First write: RxRdy (FIFO Alarm) generates rx FIFO irq 443 * Second write: register Normal mode for non loopback 444 */ 445 out_8(&psc_dma->psc_regs->mode, 0); 446 out_8(&psc_dma->psc_regs->mode, 0); 447 448 /* Set the TX and RX fifo alarm thresholds */ 449 out_be16(&psc_dma->fifo_regs->rfalarm, 0x100); 450 out_8(&psc_dma->fifo_regs->rfcntl, 0x4); 451 out_be16(&psc_dma->fifo_regs->tfalarm, 0x100); 452 out_8(&psc_dma->fifo_regs->tfcntl, 0x7); 453 454 /* Lookup the IRQ numbers */ 455 psc_dma->playback.irq = 456 bcom_get_task_irq(psc_dma->playback.bcom_task); 457 psc_dma->capture.irq = 458 bcom_get_task_irq(psc_dma->capture.bcom_task); 459 460 rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED, 461 "psc-dma-status", psc_dma); 462 rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED, 463 "psc-dma-capture", &psc_dma->capture); 464 rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED, 465 "psc-dma-playback", &psc_dma->playback); 466 if (rc) { 467 ret = -ENODEV; 468 goto out_irq; 469 } 470 471 /* Save what we've done so it can be found again later */ 472 dev_set_drvdata(&op->dev, psc_dma); 473 474 /* Tell the ASoC OF helpers about it */ 475 return devm_snd_soc_register_component(&op->dev, 476 &mpc5200_audio_dma_component, NULL, 0); 477 out_irq: 478 free_irq(psc_dma->irq, psc_dma); 479 free_irq(psc_dma->capture.irq, &psc_dma->capture); 480 free_irq(psc_dma->playback.irq, &psc_dma->playback); 481 out_free: 482 kfree(psc_dma); 483 out_unmap: 484 iounmap(regs); 485 return ret; 486 } 487 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create); 488 489 int mpc5200_audio_dma_destroy(struct platform_device *op) 490 { 491 struct psc_dma *psc_dma = dev_get_drvdata(&op->dev); 492 493 dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n"); 494 495 bcom_gen_bd_rx_release(psc_dma->capture.bcom_task); 496 bcom_gen_bd_tx_release(psc_dma->playback.bcom_task); 497 498 /* Release irqs */ 499 free_irq(psc_dma->irq, psc_dma); 500 free_irq(psc_dma->capture.irq, &psc_dma->capture); 501 free_irq(psc_dma->playback.irq, &psc_dma->playback); 502 503 iounmap(psc_dma->psc_regs); 504 kfree(psc_dma); 505 dev_set_drvdata(&op->dev, NULL); 506 507 return 0; 508 } 509 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy); 510 511 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 512 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver"); 513 MODULE_LICENSE("GPL"); 514