1 /* 2 * Freescale MPC5200 PSC DMA 3 * ALSA SoC Platform driver 4 * 5 * Copyright (C) 2008 Secret Lab Technologies Ltd. 6 * Copyright (C) 2009 Jon Smirl, Digispeaker 7 */ 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 /* 26 * Interrupt handlers 27 */ 28 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma) 29 { 30 struct psc_dma *psc_dma = _psc_dma; 31 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs; 32 u16 isr; 33 34 isr = in_be16(®s->mpc52xx_psc_isr); 35 36 /* Playback underrun error */ 37 if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP)) 38 psc_dma->stats.underrun_count++; 39 40 /* Capture overrun error */ 41 if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR)) 42 psc_dma->stats.overrun_count++; 43 44 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT); 45 46 return IRQ_HANDLED; 47 } 48 49 /** 50 * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer 51 * @s: pointer to stream private data structure 52 * 53 * Enqueues another audio period buffer into the bestcomm queue. 54 * 55 * Note: The routine must only be called when there is space available in 56 * the queue. Otherwise the enqueue will fail and the audio ring buffer 57 * will get out of sync 58 */ 59 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s) 60 { 61 struct bcom_bd *bd; 62 63 /* Prepare and enqueue the next buffer descriptor */ 64 bd = bcom_prepare_next_buffer(s->bcom_task); 65 bd->status = s->period_bytes; 66 bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes); 67 bcom_submit_next_buffer(s->bcom_task, NULL); 68 69 /* Update for next period */ 70 s->period_next = (s->period_next + 1) % s->runtime->periods; 71 } 72 73 /* Bestcomm DMA irq handler */ 74 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream) 75 { 76 struct psc_dma_stream *s = _psc_dma_stream; 77 78 spin_lock(&s->psc_dma->lock); 79 /* For each finished period, dequeue the completed period buffer 80 * and enqueue a new one in it's place. */ 81 while (bcom_buffer_done(s->bcom_task)) { 82 bcom_retrieve_buffer(s->bcom_task, NULL, NULL); 83 84 s->period_current = (s->period_current+1) % s->runtime->periods; 85 s->period_count++; 86 87 psc_dma_bcom_enqueue_next_buffer(s); 88 } 89 spin_unlock(&s->psc_dma->lock); 90 91 /* If the stream is active, then also inform the PCM middle layer 92 * of the period finished event. */ 93 if (s->active) 94 snd_pcm_period_elapsed(s->stream); 95 96 return IRQ_HANDLED; 97 } 98 99 static int psc_dma_hw_free(struct snd_pcm_substream *substream) 100 { 101 snd_pcm_set_runtime_buffer(substream, NULL); 102 return 0; 103 } 104 105 /** 106 * psc_dma_trigger: start and stop the DMA transfer. 107 * 108 * This function is called by ALSA to start, stop, pause, and resume the DMA 109 * transfer of data. 110 */ 111 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd) 112 { 113 struct snd_soc_pcm_runtime *rtd = substream->private_data; 114 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 115 struct snd_pcm_runtime *runtime = substream->runtime; 116 struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma); 117 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs; 118 u16 imr; 119 unsigned long flags; 120 int i; 121 122 switch (cmd) { 123 case SNDRV_PCM_TRIGGER_START: 124 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n", 125 substream->pstr->stream, runtime->frame_bits, 126 (int)runtime->period_size, runtime->periods); 127 s->period_bytes = frames_to_bytes(runtime, 128 runtime->period_size); 129 s->period_next = 0; 130 s->period_current = 0; 131 s->active = 1; 132 s->period_count = 0; 133 s->runtime = runtime; 134 135 /* Fill up the bestcomm bd queue and enable DMA. 136 * This will begin filling the PSC's fifo. 137 */ 138 spin_lock_irqsave(&psc_dma->lock, flags); 139 140 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 141 bcom_gen_bd_rx_reset(s->bcom_task); 142 else 143 bcom_gen_bd_tx_reset(s->bcom_task); 144 145 for (i = 0; i < runtime->periods; i++) 146 if (!bcom_queue_full(s->bcom_task)) 147 psc_dma_bcom_enqueue_next_buffer(s); 148 149 bcom_enable(s->bcom_task); 150 spin_unlock_irqrestore(&psc_dma->lock, flags); 151 152 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT); 153 154 break; 155 156 case SNDRV_PCM_TRIGGER_STOP: 157 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n", 158 substream->pstr->stream, s->period_count); 159 s->active = 0; 160 161 spin_lock_irqsave(&psc_dma->lock, flags); 162 bcom_disable(s->bcom_task); 163 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 164 bcom_gen_bd_rx_reset(s->bcom_task); 165 else 166 bcom_gen_bd_tx_reset(s->bcom_task); 167 spin_unlock_irqrestore(&psc_dma->lock, flags); 168 169 break; 170 171 default: 172 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n", 173 substream->pstr->stream, cmd); 174 return -EINVAL; 175 } 176 177 /* Update interrupt enable settings */ 178 imr = 0; 179 if (psc_dma->playback.active) 180 imr |= MPC52xx_PSC_IMR_TXEMP; 181 if (psc_dma->capture.active) 182 imr |= MPC52xx_PSC_IMR_ORERR; 183 out_be16(®s->isr_imr.imr, psc_dma->imr | imr); 184 185 return 0; 186 } 187 188 189 /* --------------------------------------------------------------------- 190 * The PSC DMA 'ASoC platform' driver 191 * 192 * Can be referenced by an 'ASoC machine' driver 193 * This driver only deals with the audio bus; it doesn't have any 194 * interaction with the attached codec 195 */ 196 197 static const struct snd_pcm_hardware psc_dma_hardware = { 198 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 199 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | 200 SNDRV_PCM_INFO_BATCH, 201 .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | 202 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE, 203 .period_bytes_max = 1024 * 1024, 204 .period_bytes_min = 32, 205 .periods_min = 2, 206 .periods_max = 256, 207 .buffer_bytes_max = 2 * 1024 * 1024, 208 .fifo_size = 512, 209 }; 210 211 static int psc_dma_open(struct snd_pcm_substream *substream) 212 { 213 struct snd_pcm_runtime *runtime = substream->runtime; 214 struct snd_soc_pcm_runtime *rtd = substream->private_data; 215 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 216 struct psc_dma_stream *s; 217 int rc; 218 219 dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream); 220 221 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 222 s = &psc_dma->capture; 223 else 224 s = &psc_dma->playback; 225 226 snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware); 227 228 rc = snd_pcm_hw_constraint_integer(runtime, 229 SNDRV_PCM_HW_PARAM_PERIODS); 230 if (rc < 0) { 231 dev_err(substream->pcm->card->dev, "invalid buffer size\n"); 232 return rc; 233 } 234 235 s->stream = substream; 236 return 0; 237 } 238 239 static int psc_dma_close(struct snd_pcm_substream *substream) 240 { 241 struct snd_soc_pcm_runtime *rtd = substream->private_data; 242 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 243 struct psc_dma_stream *s; 244 245 dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream); 246 247 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 248 s = &psc_dma->capture; 249 else 250 s = &psc_dma->playback; 251 252 if (!psc_dma->playback.active && 253 !psc_dma->capture.active) { 254 255 /* Disable all interrupts and reset the PSC */ 256 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 257 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */ 258 } 259 s->stream = NULL; 260 return 0; 261 } 262 263 static snd_pcm_uframes_t 264 psc_dma_pointer(struct snd_pcm_substream *substream) 265 { 266 struct snd_soc_pcm_runtime *rtd = substream->private_data; 267 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 268 struct psc_dma_stream *s; 269 dma_addr_t count; 270 271 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 272 s = &psc_dma->capture; 273 else 274 s = &psc_dma->playback; 275 276 count = s->period_current * s->period_bytes; 277 278 return bytes_to_frames(substream->runtime, count); 279 } 280 281 static int 282 psc_dma_hw_params(struct snd_pcm_substream *substream, 283 struct snd_pcm_hw_params *params) 284 { 285 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 286 287 return 0; 288 } 289 290 static struct snd_pcm_ops psc_dma_ops = { 291 .open = psc_dma_open, 292 .close = psc_dma_close, 293 .hw_free = psc_dma_hw_free, 294 .ioctl = snd_pcm_lib_ioctl, 295 .pointer = psc_dma_pointer, 296 .trigger = psc_dma_trigger, 297 .hw_params = psc_dma_hw_params, 298 }; 299 300 static int psc_dma_new(struct snd_soc_pcm_runtime *rtd) 301 { 302 struct snd_card *card = rtd->card->snd_card; 303 struct snd_soc_dai *dai = rtd->cpu_dai; 304 struct snd_pcm *pcm = rtd->pcm; 305 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai); 306 size_t size = psc_dma_hardware.buffer_bytes_max; 307 int rc; 308 309 dev_dbg(rtd->platform->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n", 310 card, dai, pcm); 311 312 rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 313 if (rc) 314 return rc; 315 316 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 317 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 318 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 319 if (rc) 320 goto playback_alloc_err; 321 } 322 323 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 324 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev, 325 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer); 326 if (rc) 327 goto capture_alloc_err; 328 } 329 330 return 0; 331 332 capture_alloc_err: 333 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) 334 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer); 335 336 playback_alloc_err: 337 dev_err(card->dev, "Cannot allocate buffer(s)\n"); 338 339 return -ENOMEM; 340 } 341 342 static void psc_dma_free(struct snd_pcm *pcm) 343 { 344 struct snd_soc_pcm_runtime *rtd = pcm->private_data; 345 struct snd_pcm_substream *substream; 346 int stream; 347 348 dev_dbg(rtd->platform->dev, "psc_dma_free(pcm=%p)\n", pcm); 349 350 for (stream = 0; stream < 2; stream++) { 351 substream = pcm->streams[stream].substream; 352 if (substream) { 353 snd_dma_free_pages(&substream->dma_buffer); 354 substream->dma_buffer.area = NULL; 355 substream->dma_buffer.addr = 0; 356 } 357 } 358 } 359 360 static struct snd_soc_platform_driver mpc5200_audio_dma_platform = { 361 .ops = &psc_dma_ops, 362 .pcm_new = &psc_dma_new, 363 .pcm_free = &psc_dma_free, 364 }; 365 366 int mpc5200_audio_dma_create(struct platform_device *op) 367 { 368 phys_addr_t fifo; 369 struct psc_dma *psc_dma; 370 struct resource res; 371 int size, irq, rc; 372 const __be32 *prop; 373 void __iomem *regs; 374 int ret; 375 376 /* Fetch the registers and IRQ of the PSC */ 377 irq = irq_of_parse_and_map(op->dev.of_node, 0); 378 if (of_address_to_resource(op->dev.of_node, 0, &res)) { 379 dev_err(&op->dev, "Missing reg property\n"); 380 return -ENODEV; 381 } 382 regs = ioremap(res.start, resource_size(&res)); 383 if (!regs) { 384 dev_err(&op->dev, "Could not map registers\n"); 385 return -ENODEV; 386 } 387 388 /* Allocate and initialize the driver private data */ 389 psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL); 390 if (!psc_dma) { 391 ret = -ENOMEM; 392 goto out_unmap; 393 } 394 395 /* Get the PSC ID */ 396 prop = of_get_property(op->dev.of_node, "cell-index", &size); 397 if (!prop || size < sizeof *prop) { 398 ret = -ENODEV; 399 goto out_free; 400 } 401 402 spin_lock_init(&psc_dma->lock); 403 mutex_init(&psc_dma->mutex); 404 psc_dma->id = be32_to_cpu(*prop); 405 psc_dma->irq = irq; 406 psc_dma->psc_regs = regs; 407 psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs; 408 psc_dma->dev = &op->dev; 409 psc_dma->playback.psc_dma = psc_dma; 410 psc_dma->capture.psc_dma = psc_dma; 411 snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id); 412 413 /* Find the address of the fifo data registers and setup the 414 * DMA tasks */ 415 fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32); 416 psc_dma->capture.bcom_task = 417 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512); 418 psc_dma->playback.bcom_task = 419 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo); 420 if (!psc_dma->capture.bcom_task || 421 !psc_dma->playback.bcom_task) { 422 dev_err(&op->dev, "Could not allocate bestcomm tasks\n"); 423 ret = -ENODEV; 424 goto out_free; 425 } 426 427 /* Disable all interrupts and reset the PSC */ 428 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 429 /* reset receiver */ 430 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX); 431 /* reset transmitter */ 432 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX); 433 /* reset error */ 434 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT); 435 /* reset mode */ 436 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1); 437 438 /* Set up mode register; 439 * First write: RxRdy (FIFO Alarm) generates rx FIFO irq 440 * Second write: register Normal mode for non loopback 441 */ 442 out_8(&psc_dma->psc_regs->mode, 0); 443 out_8(&psc_dma->psc_regs->mode, 0); 444 445 /* Set the TX and RX fifo alarm thresholds */ 446 out_be16(&psc_dma->fifo_regs->rfalarm, 0x100); 447 out_8(&psc_dma->fifo_regs->rfcntl, 0x4); 448 out_be16(&psc_dma->fifo_regs->tfalarm, 0x100); 449 out_8(&psc_dma->fifo_regs->tfcntl, 0x7); 450 451 /* Lookup the IRQ numbers */ 452 psc_dma->playback.irq = 453 bcom_get_task_irq(psc_dma->playback.bcom_task); 454 psc_dma->capture.irq = 455 bcom_get_task_irq(psc_dma->capture.bcom_task); 456 457 rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED, 458 "psc-dma-status", psc_dma); 459 rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED, 460 "psc-dma-capture", &psc_dma->capture); 461 rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED, 462 "psc-dma-playback", &psc_dma->playback); 463 if (rc) { 464 ret = -ENODEV; 465 goto out_irq; 466 } 467 468 /* Save what we've done so it can be found again later */ 469 dev_set_drvdata(&op->dev, psc_dma); 470 471 /* Tell the ASoC OF helpers about it */ 472 return snd_soc_register_platform(&op->dev, &mpc5200_audio_dma_platform); 473 out_irq: 474 free_irq(psc_dma->irq, psc_dma); 475 free_irq(psc_dma->capture.irq, &psc_dma->capture); 476 free_irq(psc_dma->playback.irq, &psc_dma->playback); 477 out_free: 478 kfree(psc_dma); 479 out_unmap: 480 iounmap(regs); 481 return ret; 482 } 483 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create); 484 485 int mpc5200_audio_dma_destroy(struct platform_device *op) 486 { 487 struct psc_dma *psc_dma = dev_get_drvdata(&op->dev); 488 489 dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n"); 490 491 snd_soc_unregister_platform(&op->dev); 492 493 bcom_gen_bd_rx_release(psc_dma->capture.bcom_task); 494 bcom_gen_bd_tx_release(psc_dma->playback.bcom_task); 495 496 /* Release irqs */ 497 free_irq(psc_dma->irq, psc_dma); 498 free_irq(psc_dma->capture.irq, &psc_dma->capture); 499 free_irq(psc_dma->playback.irq, &psc_dma->playback); 500 501 iounmap(psc_dma->psc_regs); 502 kfree(psc_dma); 503 dev_set_drvdata(&op->dev, NULL); 504 505 return 0; 506 } 507 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy); 508 509 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 510 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver"); 511 MODULE_LICENSE("GPL"); 512