xref: /openbmc/linux/sound/hda/hdac_stream.c (revision ebd09753)
1 /*
2  * HD-audio stream operations
3  */
4 
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/export.h>
8 #include <linux/clocksource.h>
9 #include <sound/core.h>
10 #include <sound/pcm.h>
11 #include <sound/hdaudio.h>
12 #include <sound/hda_register.h>
13 #include "trace.h"
14 
15 /**
16  * snd_hdac_stream_init - initialize each stream (aka device)
17  * @bus: HD-audio core bus
18  * @azx_dev: HD-audio core stream object to initialize
19  * @idx: stream index number
20  * @direction: stream direction (SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE)
21  * @tag: the tag id to assign
22  *
23  * Assign the starting bdl address to each stream (device) and initialize.
24  */
25 void snd_hdac_stream_init(struct hdac_bus *bus, struct hdac_stream *azx_dev,
26 			  int idx, int direction, int tag)
27 {
28 	azx_dev->bus = bus;
29 	/* offset: SDI0=0x80, SDI1=0xa0, ... SDO3=0x160 */
30 	azx_dev->sd_addr = bus->remap_addr + (0x20 * idx + 0x80);
31 	/* int mask: SDI0=0x01, SDI1=0x02, ... SDO3=0x80 */
32 	azx_dev->sd_int_sta_mask = 1 << idx;
33 	azx_dev->index = idx;
34 	azx_dev->direction = direction;
35 	azx_dev->stream_tag = tag;
36 	snd_hdac_dsp_lock_init(azx_dev);
37 	list_add_tail(&azx_dev->list, &bus->stream_list);
38 }
39 EXPORT_SYMBOL_GPL(snd_hdac_stream_init);
40 
41 /**
42  * snd_hdac_stream_start - start a stream
43  * @azx_dev: HD-audio core stream to start
44  * @fresh_start: false = wallclock timestamp relative to period wallclock
45  *
46  * Start a stream, set start_wallclk and set the running flag.
47  */
48 void snd_hdac_stream_start(struct hdac_stream *azx_dev, bool fresh_start)
49 {
50 	struct hdac_bus *bus = azx_dev->bus;
51 
52 	trace_snd_hdac_stream_start(bus, azx_dev);
53 
54 	azx_dev->start_wallclk = snd_hdac_chip_readl(bus, WALLCLK);
55 	if (!fresh_start)
56 		azx_dev->start_wallclk -= azx_dev->period_wallclk;
57 
58 	/* enable SIE */
59 	snd_hdac_chip_updatel(bus, INTCTL, 0, 1 << azx_dev->index);
60 	/* set DMA start and interrupt mask */
61 	snd_hdac_stream_updateb(azx_dev, SD_CTL,
62 				0, SD_CTL_DMA_START | SD_INT_MASK);
63 	azx_dev->running = true;
64 }
65 EXPORT_SYMBOL_GPL(snd_hdac_stream_start);
66 
67 /**
68  * snd_hdac_stream_clear - stop a stream DMA
69  * @azx_dev: HD-audio core stream to stop
70  */
71 void snd_hdac_stream_clear(struct hdac_stream *azx_dev)
72 {
73 	snd_hdac_stream_updateb(azx_dev, SD_CTL,
74 				SD_CTL_DMA_START | SD_INT_MASK, 0);
75 	snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK); /* to be sure */
76 	azx_dev->running = false;
77 }
78 EXPORT_SYMBOL_GPL(snd_hdac_stream_clear);
79 
80 /**
81  * snd_hdac_stream_stop - stop a stream
82  * @azx_dev: HD-audio core stream to stop
83  *
84  * Stop a stream DMA and disable stream interrupt
85  */
86 void snd_hdac_stream_stop(struct hdac_stream *azx_dev)
87 {
88 	trace_snd_hdac_stream_stop(azx_dev->bus, azx_dev);
89 
90 	snd_hdac_stream_clear(azx_dev);
91 	/* disable SIE */
92 	snd_hdac_chip_updatel(azx_dev->bus, INTCTL, 1 << azx_dev->index, 0);
93 }
94 EXPORT_SYMBOL_GPL(snd_hdac_stream_stop);
95 
96 /**
97  * snd_hdac_stream_reset - reset a stream
98  * @azx_dev: HD-audio core stream to reset
99  */
100 void snd_hdac_stream_reset(struct hdac_stream *azx_dev)
101 {
102 	unsigned char val;
103 	int timeout;
104 
105 	snd_hdac_stream_clear(azx_dev);
106 
107 	snd_hdac_stream_updateb(azx_dev, SD_CTL, 0, SD_CTL_STREAM_RESET);
108 	udelay(3);
109 	timeout = 300;
110 	do {
111 		val = snd_hdac_stream_readb(azx_dev, SD_CTL) &
112 			SD_CTL_STREAM_RESET;
113 		if (val)
114 			break;
115 	} while (--timeout);
116 	val &= ~SD_CTL_STREAM_RESET;
117 	snd_hdac_stream_writeb(azx_dev, SD_CTL, val);
118 	udelay(3);
119 
120 	timeout = 300;
121 	/* waiting for hardware to report that the stream is out of reset */
122 	do {
123 		val = snd_hdac_stream_readb(azx_dev, SD_CTL) &
124 			SD_CTL_STREAM_RESET;
125 		if (!val)
126 			break;
127 	} while (--timeout);
128 
129 	/* reset first position - may not be synced with hw at this time */
130 	if (azx_dev->posbuf)
131 		*azx_dev->posbuf = 0;
132 }
133 EXPORT_SYMBOL_GPL(snd_hdac_stream_reset);
134 
135 /**
136  * snd_hdac_stream_setup -  set up the SD for streaming
137  * @azx_dev: HD-audio core stream to set up
138  */
139 int snd_hdac_stream_setup(struct hdac_stream *azx_dev)
140 {
141 	struct hdac_bus *bus = azx_dev->bus;
142 	struct snd_pcm_runtime *runtime;
143 	unsigned int val;
144 
145 	if (azx_dev->substream)
146 		runtime = azx_dev->substream->runtime;
147 	else
148 		runtime = NULL;
149 	/* make sure the run bit is zero for SD */
150 	snd_hdac_stream_clear(azx_dev);
151 	/* program the stream_tag */
152 	val = snd_hdac_stream_readl(azx_dev, SD_CTL);
153 	val = (val & ~SD_CTL_STREAM_TAG_MASK) |
154 		(azx_dev->stream_tag << SD_CTL_STREAM_TAG_SHIFT);
155 	if (!bus->snoop)
156 		val |= SD_CTL_TRAFFIC_PRIO;
157 	snd_hdac_stream_writel(azx_dev, SD_CTL, val);
158 
159 	/* program the length of samples in cyclic buffer */
160 	snd_hdac_stream_writel(azx_dev, SD_CBL, azx_dev->bufsize);
161 
162 	/* program the stream format */
163 	/* this value needs to be the same as the one programmed */
164 	snd_hdac_stream_writew(azx_dev, SD_FORMAT, azx_dev->format_val);
165 
166 	/* program the stream LVI (last valid index) of the BDL */
167 	snd_hdac_stream_writew(azx_dev, SD_LVI, azx_dev->frags - 1);
168 
169 	/* program the BDL address */
170 	/* lower BDL address */
171 	snd_hdac_stream_writel(azx_dev, SD_BDLPL, (u32)azx_dev->bdl.addr);
172 	/* upper BDL address */
173 	snd_hdac_stream_writel(azx_dev, SD_BDLPU,
174 			       upper_32_bits(azx_dev->bdl.addr));
175 
176 	/* enable the position buffer */
177 	if (bus->use_posbuf && bus->posbuf.addr) {
178 		if (!(snd_hdac_chip_readl(bus, DPLBASE) & AZX_DPLBASE_ENABLE))
179 			snd_hdac_chip_writel(bus, DPLBASE,
180 				(u32)bus->posbuf.addr | AZX_DPLBASE_ENABLE);
181 	}
182 
183 	/* set the interrupt enable bits in the descriptor control register */
184 	snd_hdac_stream_updatel(azx_dev, SD_CTL, 0, SD_INT_MASK);
185 
186 	if (azx_dev->direction == SNDRV_PCM_STREAM_PLAYBACK)
187 		azx_dev->fifo_size =
188 			snd_hdac_stream_readw(azx_dev, SD_FIFOSIZE) + 1;
189 	else
190 		azx_dev->fifo_size = 0;
191 
192 	/* when LPIB delay correction gives a small negative value,
193 	 * we ignore it; currently set the threshold statically to
194 	 * 64 frames
195 	 */
196 	if (runtime && runtime->period_size > 64)
197 		azx_dev->delay_negative_threshold =
198 			-frames_to_bytes(runtime, 64);
199 	else
200 		azx_dev->delay_negative_threshold = 0;
201 
202 	/* wallclk has 24Mhz clock source */
203 	if (runtime)
204 		azx_dev->period_wallclk = (((runtime->period_size * 24000) /
205 				    runtime->rate) * 1000);
206 
207 	return 0;
208 }
209 EXPORT_SYMBOL_GPL(snd_hdac_stream_setup);
210 
211 /**
212  * snd_hdac_stream_cleanup - cleanup a stream
213  * @azx_dev: HD-audio core stream to clean up
214  */
215 void snd_hdac_stream_cleanup(struct hdac_stream *azx_dev)
216 {
217 	snd_hdac_stream_writel(azx_dev, SD_BDLPL, 0);
218 	snd_hdac_stream_writel(azx_dev, SD_BDLPU, 0);
219 	snd_hdac_stream_writel(azx_dev, SD_CTL, 0);
220 	azx_dev->bufsize = 0;
221 	azx_dev->period_bytes = 0;
222 	azx_dev->format_val = 0;
223 }
224 EXPORT_SYMBOL_GPL(snd_hdac_stream_cleanup);
225 
226 /**
227  * snd_hdac_stream_assign - assign a stream for the PCM
228  * @bus: HD-audio core bus
229  * @substream: PCM substream to assign
230  *
231  * Look for an unused stream for the given PCM substream, assign it
232  * and return the stream object.  If no stream is free, returns NULL.
233  * The function tries to keep using the same stream object when it's used
234  * beforehand.  Also, when bus->reverse_assign flag is set, the last free
235  * or matching entry is returned.  This is needed for some strange codecs.
236  */
237 struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus,
238 					   struct snd_pcm_substream *substream)
239 {
240 	struct hdac_stream *azx_dev;
241 	struct hdac_stream *res = NULL;
242 
243 	/* make a non-zero unique key for the substream */
244 	int key = (substream->pcm->device << 16) | (substream->number << 2) |
245 		(substream->stream + 1);
246 
247 	list_for_each_entry(azx_dev, &bus->stream_list, list) {
248 		if (azx_dev->direction != substream->stream)
249 			continue;
250 		if (azx_dev->opened)
251 			continue;
252 		if (azx_dev->assigned_key == key) {
253 			res = azx_dev;
254 			break;
255 		}
256 		if (!res || bus->reverse_assign)
257 			res = azx_dev;
258 	}
259 	if (res) {
260 		spin_lock_irq(&bus->reg_lock);
261 		res->opened = 1;
262 		res->running = 0;
263 		res->assigned_key = key;
264 		res->substream = substream;
265 		spin_unlock_irq(&bus->reg_lock);
266 	}
267 	return res;
268 }
269 EXPORT_SYMBOL_GPL(snd_hdac_stream_assign);
270 
271 /**
272  * snd_hdac_stream_release - release the assigned stream
273  * @azx_dev: HD-audio core stream to release
274  *
275  * Release the stream that has been assigned by snd_hdac_stream_assign().
276  */
277 void snd_hdac_stream_release(struct hdac_stream *azx_dev)
278 {
279 	struct hdac_bus *bus = azx_dev->bus;
280 
281 	spin_lock_irq(&bus->reg_lock);
282 	azx_dev->opened = 0;
283 	azx_dev->running = 0;
284 	azx_dev->substream = NULL;
285 	spin_unlock_irq(&bus->reg_lock);
286 }
287 EXPORT_SYMBOL_GPL(snd_hdac_stream_release);
288 
289 /**
290  * snd_hdac_get_stream - return hdac_stream based on stream_tag and
291  * direction
292  *
293  * @bus: HD-audio core bus
294  * @dir: direction for the stream to be found
295  * @stream_tag: stream tag for stream to be found
296  */
297 struct hdac_stream *snd_hdac_get_stream(struct hdac_bus *bus,
298 					int dir, int stream_tag)
299 {
300 	struct hdac_stream *s;
301 
302 	list_for_each_entry(s, &bus->stream_list, list) {
303 		if (s->direction == dir && s->stream_tag == stream_tag)
304 			return s;
305 	}
306 
307 	return NULL;
308 }
309 EXPORT_SYMBOL_GPL(snd_hdac_get_stream);
310 
311 /*
312  * set up a BDL entry
313  */
314 static int setup_bdle(struct hdac_bus *bus,
315 		      struct snd_dma_buffer *dmab,
316 		      struct hdac_stream *azx_dev, __le32 **bdlp,
317 		      int ofs, int size, int with_ioc)
318 {
319 	__le32 *bdl = *bdlp;
320 
321 	while (size > 0) {
322 		dma_addr_t addr;
323 		int chunk;
324 
325 		if (azx_dev->frags >= AZX_MAX_BDL_ENTRIES)
326 			return -EINVAL;
327 
328 		addr = snd_sgbuf_get_addr(dmab, ofs);
329 		/* program the address field of the BDL entry */
330 		bdl[0] = cpu_to_le32((u32)addr);
331 		bdl[1] = cpu_to_le32(upper_32_bits(addr));
332 		/* program the size field of the BDL entry */
333 		chunk = snd_sgbuf_get_chunk_size(dmab, ofs, size);
334 		/* one BDLE cannot cross 4K boundary on CTHDA chips */
335 		if (bus->align_bdle_4k) {
336 			u32 remain = 0x1000 - (ofs & 0xfff);
337 
338 			if (chunk > remain)
339 				chunk = remain;
340 		}
341 		bdl[2] = cpu_to_le32(chunk);
342 		/* program the IOC to enable interrupt
343 		 * only when the whole fragment is processed
344 		 */
345 		size -= chunk;
346 		bdl[3] = (size || !with_ioc) ? 0 : cpu_to_le32(0x01);
347 		bdl += 4;
348 		azx_dev->frags++;
349 		ofs += chunk;
350 	}
351 	*bdlp = bdl;
352 	return ofs;
353 }
354 
355 /**
356  * snd_hdac_stream_setup_periods - set up BDL entries
357  * @azx_dev: HD-audio core stream to set up
358  *
359  * Set up the buffer descriptor table of the given stream based on the
360  * period and buffer sizes of the assigned PCM substream.
361  */
362 int snd_hdac_stream_setup_periods(struct hdac_stream *azx_dev)
363 {
364 	struct hdac_bus *bus = azx_dev->bus;
365 	struct snd_pcm_substream *substream = azx_dev->substream;
366 	struct snd_pcm_runtime *runtime = substream->runtime;
367 	__le32 *bdl;
368 	int i, ofs, periods, period_bytes;
369 	int pos_adj, pos_align;
370 
371 	/* reset BDL address */
372 	snd_hdac_stream_writel(azx_dev, SD_BDLPL, 0);
373 	snd_hdac_stream_writel(azx_dev, SD_BDLPU, 0);
374 
375 	period_bytes = azx_dev->period_bytes;
376 	periods = azx_dev->bufsize / period_bytes;
377 
378 	/* program the initial BDL entries */
379 	bdl = (__le32 *)azx_dev->bdl.area;
380 	ofs = 0;
381 	azx_dev->frags = 0;
382 
383 	pos_adj = bus->bdl_pos_adj;
384 	if (!azx_dev->no_period_wakeup && pos_adj > 0) {
385 		pos_align = pos_adj;
386 		pos_adj = (pos_adj * runtime->rate + 47999) / 48000;
387 		if (!pos_adj)
388 			pos_adj = pos_align;
389 		else
390 			pos_adj = ((pos_adj + pos_align - 1) / pos_align) *
391 				pos_align;
392 		pos_adj = frames_to_bytes(runtime, pos_adj);
393 		if (pos_adj >= period_bytes) {
394 			dev_warn(bus->dev, "Too big adjustment %d\n",
395 				 pos_adj);
396 			pos_adj = 0;
397 		} else {
398 			ofs = setup_bdle(bus, snd_pcm_get_dma_buf(substream),
399 					 azx_dev,
400 					 &bdl, ofs, pos_adj, true);
401 			if (ofs < 0)
402 				goto error;
403 		}
404 	} else
405 		pos_adj = 0;
406 
407 	for (i = 0; i < periods; i++) {
408 		if (i == periods - 1 && pos_adj)
409 			ofs = setup_bdle(bus, snd_pcm_get_dma_buf(substream),
410 					 azx_dev, &bdl, ofs,
411 					 period_bytes - pos_adj, 0);
412 		else
413 			ofs = setup_bdle(bus, snd_pcm_get_dma_buf(substream),
414 					 azx_dev, &bdl, ofs,
415 					 period_bytes,
416 					 !azx_dev->no_period_wakeup);
417 		if (ofs < 0)
418 			goto error;
419 	}
420 	return 0;
421 
422  error:
423 	dev_err(bus->dev, "Too many BDL entries: buffer=%d, period=%d\n",
424 		azx_dev->bufsize, period_bytes);
425 	return -EINVAL;
426 }
427 EXPORT_SYMBOL_GPL(snd_hdac_stream_setup_periods);
428 
429 /**
430  * snd_hdac_stream_set_params - set stream parameters
431  * @azx_dev: HD-audio core stream for which parameters are to be set
432  * @format_val: format value parameter
433  *
434  * Setup the HD-audio core stream parameters from substream of the stream
435  * and passed format value
436  */
437 int snd_hdac_stream_set_params(struct hdac_stream *azx_dev,
438 				 unsigned int format_val)
439 {
440 
441 	unsigned int bufsize, period_bytes;
442 	struct snd_pcm_substream *substream = azx_dev->substream;
443 	struct snd_pcm_runtime *runtime;
444 	int err;
445 
446 	if (!substream)
447 		return -EINVAL;
448 	runtime = substream->runtime;
449 	bufsize = snd_pcm_lib_buffer_bytes(substream);
450 	period_bytes = snd_pcm_lib_period_bytes(substream);
451 
452 	if (bufsize != azx_dev->bufsize ||
453 	    period_bytes != azx_dev->period_bytes ||
454 	    format_val != azx_dev->format_val ||
455 	    runtime->no_period_wakeup != azx_dev->no_period_wakeup) {
456 		azx_dev->bufsize = bufsize;
457 		azx_dev->period_bytes = period_bytes;
458 		azx_dev->format_val = format_val;
459 		azx_dev->no_period_wakeup = runtime->no_period_wakeup;
460 		err = snd_hdac_stream_setup_periods(azx_dev);
461 		if (err < 0)
462 			return err;
463 	}
464 	return 0;
465 }
466 EXPORT_SYMBOL_GPL(snd_hdac_stream_set_params);
467 
468 static u64 azx_cc_read(const struct cyclecounter *cc)
469 {
470 	struct hdac_stream *azx_dev = container_of(cc, struct hdac_stream, cc);
471 
472 	return snd_hdac_chip_readl(azx_dev->bus, WALLCLK);
473 }
474 
475 static void azx_timecounter_init(struct hdac_stream *azx_dev,
476 				 bool force, u64 last)
477 {
478 	struct timecounter *tc = &azx_dev->tc;
479 	struct cyclecounter *cc = &azx_dev->cc;
480 	u64 nsec;
481 
482 	cc->read = azx_cc_read;
483 	cc->mask = CLOCKSOURCE_MASK(32);
484 
485 	/*
486 	 * Converting from 24 MHz to ns means applying a 125/3 factor.
487 	 * To avoid any saturation issues in intermediate operations,
488 	 * the 125 factor is applied first. The division is applied
489 	 * last after reading the timecounter value.
490 	 * Applying the 1/3 factor as part of the multiplication
491 	 * requires at least 20 bits for a decent precision, however
492 	 * overflows occur after about 4 hours or less, not a option.
493 	 */
494 
495 	cc->mult = 125; /* saturation after 195 years */
496 	cc->shift = 0;
497 
498 	nsec = 0; /* audio time is elapsed time since trigger */
499 	timecounter_init(tc, cc, nsec);
500 	if (force) {
501 		/*
502 		 * force timecounter to use predefined value,
503 		 * used for synchronized starts
504 		 */
505 		tc->cycle_last = last;
506 	}
507 }
508 
509 /**
510  * snd_hdac_stream_timecounter_init - initialize time counter
511  * @azx_dev: HD-audio core stream (master stream)
512  * @streams: bit flags of streams to set up
513  *
514  * Initializes the time counter of streams marked by the bit flags (each
515  * bit corresponds to the stream index).
516  * The trigger timestamp of PCM substream assigned to the given stream is
517  * updated accordingly, too.
518  */
519 void snd_hdac_stream_timecounter_init(struct hdac_stream *azx_dev,
520 				      unsigned int streams)
521 {
522 	struct hdac_bus *bus = azx_dev->bus;
523 	struct snd_pcm_runtime *runtime = azx_dev->substream->runtime;
524 	struct hdac_stream *s;
525 	bool inited = false;
526 	u64 cycle_last = 0;
527 	int i = 0;
528 
529 	list_for_each_entry(s, &bus->stream_list, list) {
530 		if (streams & (1 << i)) {
531 			azx_timecounter_init(s, inited, cycle_last);
532 			if (!inited) {
533 				inited = true;
534 				cycle_last = s->tc.cycle_last;
535 			}
536 		}
537 		i++;
538 	}
539 
540 	snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
541 	runtime->trigger_tstamp_latched = true;
542 }
543 EXPORT_SYMBOL_GPL(snd_hdac_stream_timecounter_init);
544 
545 /**
546  * snd_hdac_stream_sync_trigger - turn on/off stream sync register
547  * @azx_dev: HD-audio core stream (master stream)
548  * @streams: bit flags of streams to sync
549  */
550 void snd_hdac_stream_sync_trigger(struct hdac_stream *azx_dev, bool set,
551 				  unsigned int streams, unsigned int reg)
552 {
553 	struct hdac_bus *bus = azx_dev->bus;
554 	unsigned int val;
555 
556 	if (!reg)
557 		reg = AZX_REG_SSYNC;
558 	val = _snd_hdac_chip_readl(bus, reg);
559 	if (set)
560 		val |= streams;
561 	else
562 		val &= ~streams;
563 	_snd_hdac_chip_writel(bus, reg, val);
564 }
565 EXPORT_SYMBOL_GPL(snd_hdac_stream_sync_trigger);
566 
567 /**
568  * snd_hdac_stream_sync - sync with start/strop trigger operation
569  * @azx_dev: HD-audio core stream (master stream)
570  * @start: true = start, false = stop
571  * @streams: bit flags of streams to sync
572  *
573  * For @start = true, wait until all FIFOs get ready.
574  * For @start = false, wait until all RUN bits are cleared.
575  */
576 void snd_hdac_stream_sync(struct hdac_stream *azx_dev, bool start,
577 			  unsigned int streams)
578 {
579 	struct hdac_bus *bus = azx_dev->bus;
580 	int i, nwait, timeout;
581 	struct hdac_stream *s;
582 
583 	for (timeout = 5000; timeout; timeout--) {
584 		nwait = 0;
585 		i = 0;
586 		list_for_each_entry(s, &bus->stream_list, list) {
587 			if (streams & (1 << i)) {
588 				if (start) {
589 					/* check FIFO gets ready */
590 					if (!(snd_hdac_stream_readb(s, SD_STS) &
591 					      SD_STS_FIFO_READY))
592 						nwait++;
593 				} else {
594 					/* check RUN bit is cleared */
595 					if (snd_hdac_stream_readb(s, SD_CTL) &
596 					    SD_CTL_DMA_START)
597 						nwait++;
598 				}
599 			}
600 			i++;
601 		}
602 		if (!nwait)
603 			break;
604 		cpu_relax();
605 	}
606 }
607 EXPORT_SYMBOL_GPL(snd_hdac_stream_sync);
608 
609 #ifdef CONFIG_SND_HDA_DSP_LOADER
610 /**
611  * snd_hdac_dsp_prepare - prepare for DSP loading
612  * @azx_dev: HD-audio core stream used for DSP loading
613  * @format: HD-audio stream format
614  * @byte_size: data chunk byte size
615  * @bufp: allocated buffer
616  *
617  * Allocate the buffer for the given size and set up the given stream for
618  * DSP loading.  Returns the stream tag (>= 0), or a negative error code.
619  */
620 int snd_hdac_dsp_prepare(struct hdac_stream *azx_dev, unsigned int format,
621 			 unsigned int byte_size, struct snd_dma_buffer *bufp)
622 {
623 	struct hdac_bus *bus = azx_dev->bus;
624 	__le32 *bdl;
625 	int err;
626 
627 	snd_hdac_dsp_lock(azx_dev);
628 	spin_lock_irq(&bus->reg_lock);
629 	if (azx_dev->running || azx_dev->locked) {
630 		spin_unlock_irq(&bus->reg_lock);
631 		err = -EBUSY;
632 		goto unlock;
633 	}
634 	azx_dev->locked = true;
635 	spin_unlock_irq(&bus->reg_lock);
636 
637 	err = bus->io_ops->dma_alloc_pages(bus, SNDRV_DMA_TYPE_DEV_SG,
638 					   byte_size, bufp);
639 	if (err < 0)
640 		goto err_alloc;
641 
642 	azx_dev->substream = NULL;
643 	azx_dev->bufsize = byte_size;
644 	azx_dev->period_bytes = byte_size;
645 	azx_dev->format_val = format;
646 
647 	snd_hdac_stream_reset(azx_dev);
648 
649 	/* reset BDL address */
650 	snd_hdac_stream_writel(azx_dev, SD_BDLPL, 0);
651 	snd_hdac_stream_writel(azx_dev, SD_BDLPU, 0);
652 
653 	azx_dev->frags = 0;
654 	bdl = (__le32 *)azx_dev->bdl.area;
655 	err = setup_bdle(bus, bufp, azx_dev, &bdl, 0, byte_size, 0);
656 	if (err < 0)
657 		goto error;
658 
659 	snd_hdac_stream_setup(azx_dev);
660 	snd_hdac_dsp_unlock(azx_dev);
661 	return azx_dev->stream_tag;
662 
663  error:
664 	bus->io_ops->dma_free_pages(bus, bufp);
665  err_alloc:
666 	spin_lock_irq(&bus->reg_lock);
667 	azx_dev->locked = false;
668 	spin_unlock_irq(&bus->reg_lock);
669  unlock:
670 	snd_hdac_dsp_unlock(azx_dev);
671 	return err;
672 }
673 EXPORT_SYMBOL_GPL(snd_hdac_dsp_prepare);
674 
675 /**
676  * snd_hdac_dsp_trigger - start / stop DSP loading
677  * @azx_dev: HD-audio core stream used for DSP loading
678  * @start: trigger start or stop
679  */
680 void snd_hdac_dsp_trigger(struct hdac_stream *azx_dev, bool start)
681 {
682 	if (start)
683 		snd_hdac_stream_start(azx_dev, true);
684 	else
685 		snd_hdac_stream_stop(azx_dev);
686 }
687 EXPORT_SYMBOL_GPL(snd_hdac_dsp_trigger);
688 
689 /**
690  * snd_hdac_dsp_cleanup - clean up the stream from DSP loading to normal
691  * @azx_dev: HD-audio core stream used for DSP loading
692  * @dmab: buffer used by DSP loading
693  */
694 void snd_hdac_dsp_cleanup(struct hdac_stream *azx_dev,
695 			  struct snd_dma_buffer *dmab)
696 {
697 	struct hdac_bus *bus = azx_dev->bus;
698 
699 	if (!dmab->area || !azx_dev->locked)
700 		return;
701 
702 	snd_hdac_dsp_lock(azx_dev);
703 	/* reset BDL address */
704 	snd_hdac_stream_writel(azx_dev, SD_BDLPL, 0);
705 	snd_hdac_stream_writel(azx_dev, SD_BDLPU, 0);
706 	snd_hdac_stream_writel(azx_dev, SD_CTL, 0);
707 	azx_dev->bufsize = 0;
708 	azx_dev->period_bytes = 0;
709 	azx_dev->format_val = 0;
710 
711 	bus->io_ops->dma_free_pages(bus, dmab);
712 	dmab->area = NULL;
713 
714 	spin_lock_irq(&bus->reg_lock);
715 	azx_dev->locked = false;
716 	spin_unlock_irq(&bus->reg_lock);
717 	snd_hdac_dsp_unlock(azx_dev);
718 }
719 EXPORT_SYMBOL_GPL(snd_hdac_dsp_cleanup);
720 #endif /* CONFIG_SND_HDA_DSP_LOADER */
721