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_platform.h>
14
15 #include <sound/soc.h>
16
17 #include <sysdev/bestcomm/bestcomm.h>
18 #include <sysdev/bestcomm/gen_bd.h>
19 #include <asm/mpc52xx_psc.h>
20
21 #include "mpc5200_dma.h"
22
23 /*
24 * Interrupt handlers
25 */
psc_dma_status_irq(int irq,void * _psc_dma)26 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma)
27 {
28 struct psc_dma *psc_dma = _psc_dma;
29 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
30 u16 isr;
31
32 isr = in_be16(®s->mpc52xx_psc_isr);
33
34 /* Playback underrun error */
35 if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
36 psc_dma->stats.underrun_count++;
37
38 /* Capture overrun error */
39 if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
40 psc_dma->stats.overrun_count++;
41
42 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT);
43
44 return IRQ_HANDLED;
45 }
46
47 /**
48 * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer
49 * @s: pointer to stream private data structure
50 *
51 * Enqueues another audio period buffer into the bestcomm queue.
52 *
53 * Note: The routine must only be called when there is space available in
54 * the queue. Otherwise the enqueue will fail and the audio ring buffer
55 * will get out of sync
56 */
psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream * s)57 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s)
58 {
59 struct bcom_bd *bd;
60
61 /* Prepare and enqueue the next buffer descriptor */
62 bd = bcom_prepare_next_buffer(s->bcom_task);
63 bd->status = s->period_bytes;
64 bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes);
65 bcom_submit_next_buffer(s->bcom_task, NULL);
66
67 /* Update for next period */
68 s->period_next = (s->period_next + 1) % s->runtime->periods;
69 }
70
71 /* Bestcomm DMA irq handler */
psc_dma_bcom_irq(int irq,void * _psc_dma_stream)72 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream)
73 {
74 struct psc_dma_stream *s = _psc_dma_stream;
75
76 spin_lock(&s->psc_dma->lock);
77 /* For each finished period, dequeue the completed period buffer
78 * and enqueue a new one in it's place. */
79 while (bcom_buffer_done(s->bcom_task)) {
80 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
81
82 s->period_current = (s->period_current+1) % s->runtime->periods;
83 s->period_count++;
84
85 psc_dma_bcom_enqueue_next_buffer(s);
86 }
87 spin_unlock(&s->psc_dma->lock);
88
89 /* If the stream is active, then also inform the PCM middle layer
90 * of the period finished event. */
91 if (s->active)
92 snd_pcm_period_elapsed(s->stream);
93
94 return IRQ_HANDLED;
95 }
96
psc_dma_hw_free(struct snd_pcm_substream * substream)97 static int psc_dma_hw_free(struct snd_pcm_substream *substream)
98 {
99 snd_pcm_set_runtime_buffer(substream, NULL);
100 return 0;
101 }
102
103 /**
104 * psc_dma_trigger: start and stop the DMA transfer.
105 *
106 * This function is called by ALSA to start, stop, pause, and resume the DMA
107 * transfer of data.
108 */
psc_dma_trigger(struct snd_pcm_substream * substream,int cmd)109 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
110 {
111 struct snd_soc_pcm_runtime *rtd = substream->private_data;
112 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
113 struct snd_pcm_runtime *runtime = substream->runtime;
114 struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
115 struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
116 u16 imr;
117 unsigned long flags;
118 int i;
119
120 switch (cmd) {
121 case SNDRV_PCM_TRIGGER_START:
122 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
123 substream->pstr->stream, runtime->frame_bits,
124 (int)runtime->period_size, runtime->periods);
125 s->period_bytes = frames_to_bytes(runtime,
126 runtime->period_size);
127 s->period_next = 0;
128 s->period_current = 0;
129 s->active = 1;
130 s->period_count = 0;
131 s->runtime = runtime;
132
133 /* Fill up the bestcomm bd queue and enable DMA.
134 * This will begin filling the PSC's fifo.
135 */
136 spin_lock_irqsave(&psc_dma->lock, flags);
137
138 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
139 bcom_gen_bd_rx_reset(s->bcom_task);
140 else
141 bcom_gen_bd_tx_reset(s->bcom_task);
142
143 for (i = 0; i < runtime->periods; i++)
144 if (!bcom_queue_full(s->bcom_task))
145 psc_dma_bcom_enqueue_next_buffer(s);
146
147 bcom_enable(s->bcom_task);
148 spin_unlock_irqrestore(&psc_dma->lock, flags);
149
150 out_8(®s->command, MPC52xx_PSC_RST_ERR_STAT);
151
152 break;
153
154 case SNDRV_PCM_TRIGGER_STOP:
155 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
156 substream->pstr->stream, s->period_count);
157 s->active = 0;
158
159 spin_lock_irqsave(&psc_dma->lock, flags);
160 bcom_disable(s->bcom_task);
161 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
162 bcom_gen_bd_rx_reset(s->bcom_task);
163 else
164 bcom_gen_bd_tx_reset(s->bcom_task);
165 spin_unlock_irqrestore(&psc_dma->lock, flags);
166
167 break;
168
169 default:
170 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
171 substream->pstr->stream, cmd);
172 return -EINVAL;
173 }
174
175 /* Update interrupt enable settings */
176 imr = 0;
177 if (psc_dma->playback.active)
178 imr |= MPC52xx_PSC_IMR_TXEMP;
179 if (psc_dma->capture.active)
180 imr |= MPC52xx_PSC_IMR_ORERR;
181 out_be16(®s->isr_imr.imr, psc_dma->imr | imr);
182
183 return 0;
184 }
185
186
187 /* ---------------------------------------------------------------------
188 * The PSC DMA 'ASoC platform' driver
189 *
190 * Can be referenced by an 'ASoC machine' driver
191 * This driver only deals with the audio bus; it doesn't have any
192 * interaction with the attached codec
193 */
194
195 static const struct snd_pcm_hardware psc_dma_hardware = {
196 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
197 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
198 SNDRV_PCM_INFO_BATCH,
199 .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
200 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
201 .rate_min = 8000,
202 .rate_max = 48000,
203 .channels_min = 1,
204 .channels_max = 2,
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
psc_dma_open(struct snd_pcm_substream * substream)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
psc_dma_close(struct snd_pcm_substream * substream)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
psc_dma_pointer(struct snd_pcm_substream * substream)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
psc_dma_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)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 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 u64 psc_dma_dmamask = DMA_BIT_MASK(32);
psc_dma_new(struct snd_soc_pcm_runtime * rtd)303 static int psc_dma_new(struct snd_soc_pcm_runtime *rtd)
304 {
305 struct snd_card *card = rtd->card->snd_card;
306 struct snd_soc_dai *dai = rtd->cpu_dai;
307 struct snd_pcm *pcm = rtd->pcm;
308 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
309 size_t size = psc_dma_hardware.buffer_bytes_max;
310 int rc = 0;
311
312 dev_dbg(rtd->platform->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
313 card, dai, pcm);
314
315 if (!card->dev->dma_mask)
316 card->dev->dma_mask = &psc_dma_dmamask;
317 if (!card->dev->coherent_dma_mask)
318 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
319
320 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
321 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
322 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
323 if (rc)
324 goto playback_alloc_err;
325 }
326
327 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
328 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
329 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer);
330 if (rc)
331 goto capture_alloc_err;
332 }
333
334 if (rtd->codec->ac97)
335 rtd->codec->ac97->private_data = psc_dma;
336
337 return 0;
338
339 capture_alloc_err:
340 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
341 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
342
343 playback_alloc_err:
344 dev_err(card->dev, "Cannot allocate buffer(s)\n");
345
346 return -ENOMEM;
347 }
348
psc_dma_free(struct snd_pcm * pcm)349 static void psc_dma_free(struct snd_pcm *pcm)
350 {
351 struct snd_soc_pcm_runtime *rtd = pcm->private_data;
352 struct snd_pcm_substream *substream;
353 int stream;
354
355 dev_dbg(rtd->platform->dev, "psc_dma_free(pcm=%p)\n", pcm);
356
357 for (stream = 0; stream < 2; stream++) {
358 substream = pcm->streams[stream].substream;
359 if (substream) {
360 snd_dma_free_pages(&substream->dma_buffer);
361 substream->dma_buffer.area = NULL;
362 substream->dma_buffer.addr = 0;
363 }
364 }
365 }
366
367 static struct snd_soc_platform_driver mpc5200_audio_dma_platform = {
368 .ops = &psc_dma_ops,
369 .pcm_new = &psc_dma_new,
370 .pcm_free = &psc_dma_free,
371 };
372
mpc5200_hpcd_probe(struct platform_device * op)373 static int mpc5200_hpcd_probe(struct platform_device *op)
374 {
375 phys_addr_t fifo;
376 struct psc_dma *psc_dma;
377 struct resource res;
378 int size, irq, rc;
379 const __be32 *prop;
380 void __iomem *regs;
381 int ret;
382
383 /* Fetch the registers and IRQ of the PSC */
384 irq = irq_of_parse_and_map(op->dev.of_node, 0);
385 if (of_address_to_resource(op->dev.of_node, 0, &res)) {
386 dev_err(&op->dev, "Missing reg property\n");
387 return -ENODEV;
388 }
389 regs = ioremap(res.start, resource_size(&res));
390 if (!regs) {
391 dev_err(&op->dev, "Could not map registers\n");
392 return -ENODEV;
393 }
394
395 /* Allocate and initialize the driver private data */
396 psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL);
397 if (!psc_dma) {
398 ret = -ENOMEM;
399 goto out_unmap;
400 }
401
402 /* Get the PSC ID */
403 prop = of_get_property(op->dev.of_node, "cell-index", &size);
404 if (!prop || size < sizeof *prop) {
405 ret = -ENODEV;
406 goto out_free;
407 }
408
409 spin_lock_init(&psc_dma->lock);
410 mutex_init(&psc_dma->mutex);
411 psc_dma->id = be32_to_cpu(*prop);
412 psc_dma->irq = irq;
413 psc_dma->psc_regs = regs;
414 psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs;
415 psc_dma->dev = &op->dev;
416 psc_dma->playback.psc_dma = psc_dma;
417 psc_dma->capture.psc_dma = psc_dma;
418 snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id);
419
420 /* Find the address of the fifo data registers and setup the
421 * DMA tasks */
422 fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
423 psc_dma->capture.bcom_task =
424 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512);
425 psc_dma->playback.bcom_task =
426 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo);
427 if (!psc_dma->capture.bcom_task ||
428 !psc_dma->playback.bcom_task) {
429 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
430 ret = -ENODEV;
431 goto out_free;
432 }
433
434 /* Disable all interrupts and reset the PSC */
435 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
436 /* reset receiver */
437 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX);
438 /* reset transmitter */
439 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX);
440 /* reset error */
441 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT);
442 /* reset mode */
443 out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1);
444
445 /* Set up mode register;
446 * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
447 * Second write: register Normal mode for non loopback
448 */
449 out_8(&psc_dma->psc_regs->mode, 0);
450 out_8(&psc_dma->psc_regs->mode, 0);
451
452 /* Set the TX and RX fifo alarm thresholds */
453 out_be16(&psc_dma->fifo_regs->rfalarm, 0x100);
454 out_8(&psc_dma->fifo_regs->rfcntl, 0x4);
455 out_be16(&psc_dma->fifo_regs->tfalarm, 0x100);
456 out_8(&psc_dma->fifo_regs->tfcntl, 0x7);
457
458 /* Lookup the IRQ numbers */
459 psc_dma->playback.irq =
460 bcom_get_task_irq(psc_dma->playback.bcom_task);
461 psc_dma->capture.irq =
462 bcom_get_task_irq(psc_dma->capture.bcom_task);
463
464 rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED,
465 "psc-dma-status", psc_dma);
466 rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED,
467 "psc-dma-capture", &psc_dma->capture);
468 rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED,
469 "psc-dma-playback", &psc_dma->playback);
470 if (rc) {
471 ret = -ENODEV;
472 goto out_irq;
473 }
474
475 /* Save what we've done so it can be found again later */
476 dev_set_drvdata(&op->dev, psc_dma);
477
478 /* Tell the ASoC OF helpers about it */
479 return snd_soc_register_platform(&op->dev, &mpc5200_audio_dma_platform);
480 out_irq:
481 free_irq(psc_dma->irq, psc_dma);
482 free_irq(psc_dma->capture.irq, &psc_dma->capture);
483 free_irq(psc_dma->playback.irq, &psc_dma->playback);
484 out_free:
485 kfree(psc_dma);
486 out_unmap:
487 iounmap(regs);
488 return ret;
489 }
490
mpc5200_hpcd_remove(struct platform_device * op)491 static int mpc5200_hpcd_remove(struct platform_device *op)
492 {
493 struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
494
495 dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
496
497 snd_soc_unregister_platform(&op->dev);
498
499 bcom_gen_bd_rx_release(psc_dma->capture.bcom_task);
500 bcom_gen_bd_tx_release(psc_dma->playback.bcom_task);
501
502 /* Release irqs */
503 free_irq(psc_dma->irq, psc_dma);
504 free_irq(psc_dma->capture.irq, &psc_dma->capture);
505 free_irq(psc_dma->playback.irq, &psc_dma->playback);
506
507 iounmap(psc_dma->psc_regs);
508 kfree(psc_dma);
509 dev_set_drvdata(&op->dev, NULL);
510
511 return 0;
512 }
513
514 static struct of_device_id mpc5200_hpcd_match[] = {
515 { .compatible = "fsl,mpc5200-pcm", },
516 {}
517 };
518 MODULE_DEVICE_TABLE(of, mpc5200_hpcd_match);
519
520 static struct platform_driver mpc5200_hpcd_of_driver = {
521 .probe = mpc5200_hpcd_probe,
522 .remove = mpc5200_hpcd_remove,
523 .driver = {
524 .owner = THIS_MODULE,
525 .name = "mpc5200-pcm-audio",
526 .of_match_table = mpc5200_hpcd_match,
527 }
528 };
529
530 module_platform_driver(mpc5200_hpcd_of_driver);
531
532 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
533 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
534 MODULE_LICENSE("GPL");
535