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 /** 102 * psc_dma_trigger: start and stop the DMA transfer. 103 * @component: triggered component 104 * @substream: triggered substream 105 * @cmd: triggered command 106 * 107 * This function is called by ALSA to start, stop, pause, and resume the DMA 108 * transfer of data. 109 */ 110 static int psc_dma_trigger(struct snd_soc_component *component, 111 struct snd_pcm_substream *substream, int cmd) 112 { 113 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 114 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 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_soc_component *component, 212 struct snd_pcm_substream *substream) 213 { 214 struct snd_pcm_runtime *runtime = substream->runtime; 215 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 216 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 217 struct psc_dma_stream *s; 218 int rc; 219 220 dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream); 221 222 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 223 s = &psc_dma->capture; 224 else 225 s = &psc_dma->playback; 226 227 snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware); 228 229 rc = snd_pcm_hw_constraint_integer(runtime, 230 SNDRV_PCM_HW_PARAM_PERIODS); 231 if (rc < 0) { 232 dev_err(substream->pcm->card->dev, "invalid buffer size\n"); 233 return rc; 234 } 235 236 s->stream = substream; 237 return 0; 238 } 239 240 static int psc_dma_close(struct snd_soc_component *component, 241 struct snd_pcm_substream *substream) 242 { 243 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 244 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 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_soc_component *component, 267 struct snd_pcm_substream *substream) 268 { 269 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream); 270 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0)); 271 struct psc_dma_stream *s; 272 dma_addr_t count; 273 274 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) 275 s = &psc_dma->capture; 276 else 277 s = &psc_dma->playback; 278 279 count = s->period_current * s->period_bytes; 280 281 return bytes_to_frames(substream->runtime, count); 282 } 283 284 static int psc_dma_new(struct snd_soc_component *component, 285 struct snd_soc_pcm_runtime *rtd) 286 { 287 struct snd_card *card = rtd->card->snd_card; 288 struct snd_soc_dai *dai = asoc_rtd_to_cpu(rtd, 0); 289 struct snd_pcm *pcm = rtd->pcm; 290 size_t size = psc_dma_hardware.buffer_bytes_max; 291 int rc; 292 293 dev_dbg(component->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n", 294 card, dai, pcm); 295 296 rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 297 if (rc) 298 return rc; 299 300 return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, card->dev, 301 size); 302 } 303 304 static const struct snd_soc_component_driver mpc5200_audio_dma_component = { 305 .name = DRV_NAME, 306 .open = psc_dma_open, 307 .close = psc_dma_close, 308 .pointer = psc_dma_pointer, 309 .trigger = psc_dma_trigger, 310 .pcm_construct = psc_dma_new, 311 }; 312 313 int mpc5200_audio_dma_create(struct platform_device *op) 314 { 315 phys_addr_t fifo; 316 struct psc_dma *psc_dma; 317 struct resource res; 318 int size, irq, rc; 319 const __be32 *prop; 320 void __iomem *regs; 321 int ret; 322 323 /* Fetch the registers and IRQ of the PSC */ 324 irq = irq_of_parse_and_map(op->dev.of_node, 0); 325 if (of_address_to_resource(op->dev.of_node, 0, &res)) { 326 dev_err(&op->dev, "Missing reg property\n"); 327 return -ENODEV; 328 } 329 regs = ioremap(res.start, resource_size(&res)); 330 if (!regs) { 331 dev_err(&op->dev, "Could not map registers\n"); 332 return -ENODEV; 333 } 334 335 /* Allocate and initialize the driver private data */ 336 psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL); 337 if (!psc_dma) { 338 ret = -ENOMEM; 339 goto out_unmap; 340 } 341 342 /* Get the PSC ID */ 343 prop = of_get_property(op->dev.of_node, "cell-index", &size); 344 if (!prop || size < sizeof *prop) { 345 ret = -ENODEV; 346 goto out_free; 347 } 348 349 spin_lock_init(&psc_dma->lock); 350 mutex_init(&psc_dma->mutex); 351 psc_dma->id = be32_to_cpu(*prop); 352 psc_dma->irq = irq; 353 psc_dma->psc_regs = regs; 354 psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs; 355 psc_dma->dev = &op->dev; 356 psc_dma->playback.psc_dma = psc_dma; 357 psc_dma->capture.psc_dma = psc_dma; 358 snprintf(psc_dma->name, sizeof(psc_dma->name), "PSC%d", psc_dma->id); 359 360 /* Find the address of the fifo data registers and setup the 361 * DMA tasks */ 362 fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32); 363 psc_dma->capture.bcom_task = 364 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512); 365 psc_dma->playback.bcom_task = 366 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo); 367 if (!psc_dma->capture.bcom_task || 368 !psc_dma->playback.bcom_task) { 369 dev_err(&op->dev, "Could not allocate bestcomm tasks\n"); 370 ret = -ENODEV; 371 goto out_free; 372 } 373 374 /* Disable all interrupts and reset the PSC */ 375 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr); 376 /* reset receiver */ 377 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX); 378 /* reset transmitter */ 379 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX); 380 /* reset error */ 381 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT); 382 /* reset mode */ 383 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1); 384 385 /* Set up mode register; 386 * First write: RxRdy (FIFO Alarm) generates rx FIFO irq 387 * Second write: register Normal mode for non loopback 388 */ 389 out_8(&psc_dma->psc_regs->mode, 0); 390 out_8(&psc_dma->psc_regs->mode, 0); 391 392 /* Set the TX and RX fifo alarm thresholds */ 393 out_be16(&psc_dma->fifo_regs->rfalarm, 0x100); 394 out_8(&psc_dma->fifo_regs->rfcntl, 0x4); 395 out_be16(&psc_dma->fifo_regs->tfalarm, 0x100); 396 out_8(&psc_dma->fifo_regs->tfcntl, 0x7); 397 398 /* Lookup the IRQ numbers */ 399 psc_dma->playback.irq = 400 bcom_get_task_irq(psc_dma->playback.bcom_task); 401 psc_dma->capture.irq = 402 bcom_get_task_irq(psc_dma->capture.bcom_task); 403 404 rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED, 405 "psc-dma-status", psc_dma); 406 rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED, 407 "psc-dma-capture", &psc_dma->capture); 408 rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED, 409 "psc-dma-playback", &psc_dma->playback); 410 if (rc) { 411 ret = -ENODEV; 412 goto out_irq; 413 } 414 415 /* Save what we've done so it can be found again later */ 416 dev_set_drvdata(&op->dev, psc_dma); 417 418 /* Tell the ASoC OF helpers about it */ 419 return devm_snd_soc_register_component(&op->dev, 420 &mpc5200_audio_dma_component, NULL, 0); 421 out_irq: 422 free_irq(psc_dma->irq, psc_dma); 423 free_irq(psc_dma->capture.irq, &psc_dma->capture); 424 free_irq(psc_dma->playback.irq, &psc_dma->playback); 425 out_free: 426 kfree(psc_dma); 427 out_unmap: 428 iounmap(regs); 429 return ret; 430 } 431 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create); 432 433 int mpc5200_audio_dma_destroy(struct platform_device *op) 434 { 435 struct psc_dma *psc_dma = dev_get_drvdata(&op->dev); 436 437 dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n"); 438 439 bcom_gen_bd_rx_release(psc_dma->capture.bcom_task); 440 bcom_gen_bd_tx_release(psc_dma->playback.bcom_task); 441 442 /* Release irqs */ 443 free_irq(psc_dma->irq, psc_dma); 444 free_irq(psc_dma->capture.irq, &psc_dma->capture); 445 free_irq(psc_dma->playback.irq, &psc_dma->playback); 446 447 iounmap(psc_dma->psc_regs); 448 kfree(psc_dma); 449 dev_set_drvdata(&op->dev, NULL); 450 451 return 0; 452 } 453 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy); 454 455 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 456 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver"); 457 MODULE_LICENSE("GPL"); 458