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_pcm_substream *substream) 102 { 103 snd_pcm_set_runtime_buffer(substream, NULL); 104 return 0; 105 } 106 107 /** 108 * psc_dma_trigger: start and stop the DMA transfer. 109 * 110 * This function is called by ALSA to start, stop, pause, and resume the DMA 111 * transfer of data. 112 */ 113 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd) 114 { 115 struct snd_soc_pcm_runtime *rtd = substream->private_data; 116 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 117 struct snd_pcm_runtime *runtime = substream->runtime; 118 struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma); 119 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs; 120 u16 imr; 121 unsigned long flags; 122 int i; 123 124 switch (cmd) { 125 case SNDRV_PCM_TRIGGER_START: 126 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n", 127 substream->pstr->stream, runtime->frame_bits, 128 (int)runtime->period_size, runtime->periods); 129 s->period_bytes = frames_to_bytes(runtime, 130 runtime->period_size); 131 s->period_next = 0; 132 s->period_current = 0; 133 s->active = 1; 134 s->period_count = 0; 135 s->runtime = runtime; 136 137 /* Fill up the bestcomm bd queue and enable DMA. 138 * This will begin filling the PSC's fifo. 139 */ 140 spin_lock_irqsave(&psc_dma->lock, flags); 141 142 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 143 bcom_gen_bd_rx_reset(s->bcom_task); 144 else 145 bcom_gen_bd_tx_reset(s->bcom_task); 146 147 for (i = 0; i < runtime->periods; i++) 148 if (!bcom_queue_full(s->bcom_task)) 149 psc_dma_bcom_enqueue_next_buffer(s); 150 151 bcom_enable(s->bcom_task); 152 spin_unlock_irqrestore(&psc_dma->lock, flags); 153 154 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT); 155 156 break; 157 158 case SNDRV_PCM_TRIGGER_STOP: 159 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n", 160 substream->pstr->stream, s->period_count); 161 s->active = 0; 162 163 spin_lock_irqsave(&psc_dma->lock, flags); 164 bcom_disable(s->bcom_task); 165 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 166 bcom_gen_bd_rx_reset(s->bcom_task); 167 else 168 bcom_gen_bd_tx_reset(s->bcom_task); 169 spin_unlock_irqrestore(&psc_dma->lock, flags); 170 171 break; 172 173 default: 174 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n", 175 substream->pstr->stream, cmd); 176 return -EINVAL; 177 } 178 179 /* Update interrupt enable settings */ 180 imr = 0; 181 if (psc_dma->playback.active) 182 imr |= MPC52xx_PSC_IMR_TXEMP; 183 if (psc_dma->capture.active) 184 imr |= MPC52xx_PSC_IMR_ORERR; 185 out_be16(®s->isr_imr.imr, psc_dma->imr | imr); 186 187 return 0; 188 } 189 190 191 /* --------------------------------------------------------------------- 192 * The PSC DMA 'ASoC platform' driver 193 * 194 * Can be referenced by an 'ASoC machine' driver 195 * This driver only deals with the audio bus; it doesn't have any 196 * interaction with the attached codec 197 */ 198 199 static const struct snd_pcm_hardware psc_dma_hardware = { 200 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 201 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | 202 SNDRV_PCM_INFO_BATCH, 203 .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | 204 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE, 205 .period_bytes_max = 1024 * 1024, 206 .period_bytes_min = 32, 207 .periods_min = 2, 208 .periods_max = 256, 209 .buffer_bytes_max = 2 * 1024 * 1024, 210 .fifo_size = 512, 211 }; 212 213 static int psc_dma_open(struct snd_pcm_substream *substream) 214 { 215 struct snd_pcm_runtime *runtime = substream->runtime; 216 struct snd_soc_pcm_runtime *rtd = substream->private_data; 217 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 218 struct psc_dma_stream *s; 219 int rc; 220 221 dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream); 222 223 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 224 s = &psc_dma->capture; 225 else 226 s = &psc_dma->playback; 227 228 snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware); 229 230 rc = snd_pcm_hw_constraint_integer(runtime, 231 SNDRV_PCM_HW_PARAM_PERIODS); 232 if (rc < 0) { 233 dev_err(substream->pcm->card->dev, "invalid buffer size\n"); 234 return rc; 235 } 236 237 s->stream = substream; 238 return 0; 239 } 240 241 static int psc_dma_close(struct snd_pcm_substream *substream) 242 { 243 struct snd_soc_pcm_runtime *rtd = substream->private_data; 244 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 245 struct psc_dma_stream *s; 246 247 dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream); 248 249 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 250 s = &psc_dma->capture; 251 else 252 s = &psc_dma->playback; 253 254 if (!psc_dma->playback.active && 255 !psc_dma->capture.active) { 256 257 /* Disable all interrupts and reset the PSC */ 258 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 259 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */ 260 } 261 s->stream = NULL; 262 return 0; 263 } 264 265 static snd_pcm_uframes_t 266 psc_dma_pointer(struct snd_pcm_substream *substream) 267 { 268 struct snd_soc_pcm_runtime *rtd = substream->private_data; 269 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 270 struct psc_dma_stream *s; 271 dma_addr_t count; 272 273 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 274 s = &psc_dma->capture; 275 else 276 s = &psc_dma->playback; 277 278 count = s->period_current * s->period_bytes; 279 280 return bytes_to_frames(substream->runtime, count); 281 } 282 283 static int 284 psc_dma_hw_params(struct snd_pcm_substream *substream, 285 struct snd_pcm_hw_params *params) 286 { 287 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 288 289 return 0; 290 } 291 292 static const struct snd_pcm_ops psc_dma_ops = { 293 .open = psc_dma_open, 294 .close = psc_dma_close, 295 .hw_free = psc_dma_hw_free, 296 .ioctl = snd_pcm_lib_ioctl, 297 .pointer = psc_dma_pointer, 298 .trigger = psc_dma_trigger, 299 .hw_params = psc_dma_hw_params, 300 }; 301 302 static int psc_dma_new(struct snd_soc_pcm_runtime *rtd) 303 { 304 struct snd_card *card = rtd->card->snd_card; 305 struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME); 306 struct snd_soc_dai *dai = rtd->cpu_dai; 307 struct snd_pcm *pcm = rtd->pcm; 308 size_t size = psc_dma_hardware.buffer_bytes_max; 309 int rc; 310 311 dev_dbg(component->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n", 312 card, dai, pcm); 313 314 rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 315 if (rc) 316 return rc; 317 318 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 319 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 320 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 321 if (rc) 322 goto playback_alloc_err; 323 } 324 325 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 326 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 327 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer); 328 if (rc) 329 goto capture_alloc_err; 330 } 331 332 return 0; 333 334 capture_alloc_err: 335 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) 336 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 337 338 playback_alloc_err: 339 dev_err(card->dev, "Cannot allocate buffer(s)\n"); 340 341 return -ENOMEM; 342 } 343 344 static void psc_dma_free(struct snd_pcm *pcm) 345 { 346 struct snd_soc_pcm_runtime *rtd = pcm->private_data; 347 struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME); 348 struct snd_pcm_substream *substream; 349 int stream; 350 351 dev_dbg(component->dev, "psc_dma_free(pcm=%p)\n", pcm); 352 353 for (stream = 0; stream < 2; stream++) { 354 substream = pcm->streams[stream].substream; 355 if (substream) { 356 snd_dma_free_pages(&substream->dma_buffer); 357 substream->dma_buffer.area = NULL; 358 substream->dma_buffer.addr = 0; 359 } 360 } 361 } 362 363 static const struct snd_soc_component_driver mpc5200_audio_dma_component = { 364 .name = DRV_NAME, 365 .ops = &psc_dma_ops, 366 .pcm_new = &psc_dma_new, 367 .pcm_free = &psc_dma_free, 368 }; 369 370 int mpc5200_audio_dma_create(struct platform_device *op) 371 { 372 phys_addr_t fifo; 373 struct psc_dma *psc_dma; 374 struct resource res; 375 int size, irq, rc; 376 const __be32 *prop; 377 void __iomem *regs; 378 int ret; 379 380 /* Fetch the registers and IRQ of the PSC */ 381 irq = irq_of_parse_and_map(op->dev.of_node, 0); 382 if (of_address_to_resource(op->dev.of_node, 0, &res)) { 383 dev_err(&op->dev, "Missing reg property\n"); 384 return -ENODEV; 385 } 386 regs = ioremap(res.start, resource_size(&res)); 387 if (!regs) { 388 dev_err(&op->dev, "Could not map registers\n"); 389 return -ENODEV; 390 } 391 392 /* Allocate and initialize the driver private data */ 393 psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL); 394 if (!psc_dma) { 395 ret = -ENOMEM; 396 goto out_unmap; 397 } 398 399 /* Get the PSC ID */ 400 prop = of_get_property(op->dev.of_node, "cell-index", &size); 401 if (!prop || size < sizeof *prop) { 402 ret = -ENODEV; 403 goto out_free; 404 } 405 406 spin_lock_init(&psc_dma->lock); 407 mutex_init(&psc_dma->mutex); 408 psc_dma->id = be32_to_cpu(*prop); 409 psc_dma->irq = irq; 410 psc_dma->psc_regs = regs; 411 psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs; 412 psc_dma->dev = &op->dev; 413 psc_dma->playback.psc_dma = psc_dma; 414 psc_dma->capture.psc_dma = psc_dma; 415 snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id); 416 417 /* Find the address of the fifo data registers and setup the 418 * DMA tasks */ 419 fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32); 420 psc_dma->capture.bcom_task = 421 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512); 422 psc_dma->playback.bcom_task = 423 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo); 424 if (!psc_dma->capture.bcom_task || 425 !psc_dma->playback.bcom_task) { 426 dev_err(&op->dev, "Could not allocate bestcomm tasks\n"); 427 ret = -ENODEV; 428 goto out_free; 429 } 430 431 /* Disable all interrupts and reset the PSC */ 432 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 433 /* reset receiver */ 434 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX); 435 /* reset transmitter */ 436 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX); 437 /* reset error */ 438 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT); 439 /* reset mode */ 440 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1); 441 442 /* Set up mode register; 443 * First write: RxRdy (FIFO Alarm) generates rx FIFO irq 444 * Second write: register Normal mode for non loopback 445 */ 446 out_8(&psc_dma->psc_regs->mode, 0); 447 out_8(&psc_dma->psc_regs->mode, 0); 448 449 /* Set the TX and RX fifo alarm thresholds */ 450 out_be16(&psc_dma->fifo_regs->rfalarm, 0x100); 451 out_8(&psc_dma->fifo_regs->rfcntl, 0x4); 452 out_be16(&psc_dma->fifo_regs->tfalarm, 0x100); 453 out_8(&psc_dma->fifo_regs->tfcntl, 0x7); 454 455 /* Lookup the IRQ numbers */ 456 psc_dma->playback.irq = 457 bcom_get_task_irq(psc_dma->playback.bcom_task); 458 psc_dma->capture.irq = 459 bcom_get_task_irq(psc_dma->capture.bcom_task); 460 461 rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED, 462 "psc-dma-status", psc_dma); 463 rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED, 464 "psc-dma-capture", &psc_dma->capture); 465 rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED, 466 "psc-dma-playback", &psc_dma->playback); 467 if (rc) { 468 ret = -ENODEV; 469 goto out_irq; 470 } 471 472 /* Save what we've done so it can be found again later */ 473 dev_set_drvdata(&op->dev, psc_dma); 474 475 /* Tell the ASoC OF helpers about it */ 476 return devm_snd_soc_register_component(&op->dev, 477 &mpc5200_audio_dma_component, NULL, 0); 478 out_irq: 479 free_irq(psc_dma->irq, psc_dma); 480 free_irq(psc_dma->capture.irq, &psc_dma->capture); 481 free_irq(psc_dma->playback.irq, &psc_dma->playback); 482 out_free: 483 kfree(psc_dma); 484 out_unmap: 485 iounmap(regs); 486 return ret; 487 } 488 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create); 489 490 int mpc5200_audio_dma_destroy(struct platform_device *op) 491 { 492 struct psc_dma *psc_dma = dev_get_drvdata(&op->dev); 493 494 dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n"); 495 496 bcom_gen_bd_rx_release(psc_dma->capture.bcom_task); 497 bcom_gen_bd_tx_release(psc_dma->playback.bcom_task); 498 499 /* Release irqs */ 500 free_irq(psc_dma->irq, psc_dma); 501 free_irq(psc_dma->capture.irq, &psc_dma->capture); 502 free_irq(psc_dma->playback.irq, &psc_dma->playback); 503 504 iounmap(psc_dma->psc_regs); 505 kfree(psc_dma); 506 dev_set_drvdata(&op->dev, NULL); 507 508 return 0; 509 } 510 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy); 511 512 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 513 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver"); 514 MODULE_LICENSE("GPL"); 515