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