xref: /openbmc/linux/sound/hda/hdac_controller.c (revision cc6c6912)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HD-audio controller helpers
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/delay.h>
8 #include <linux/export.h>
9 #include <sound/core.h>
10 #include <sound/hdaudio.h>
11 #include <sound/hda_register.h>
12 
13 /* clear CORB read pointer properly */
14 static void azx_clear_corbrp(struct hdac_bus *bus)
15 {
16 	int timeout;
17 
18 	for (timeout = 1000; timeout > 0; timeout--) {
19 		if (snd_hdac_chip_readw(bus, CORBRP) & AZX_CORBRP_RST)
20 			break;
21 		udelay(1);
22 	}
23 	if (timeout <= 0)
24 		dev_err(bus->dev, "CORB reset timeout#1, CORBRP = %d\n",
25 			snd_hdac_chip_readw(bus, CORBRP));
26 
27 	snd_hdac_chip_writew(bus, CORBRP, 0);
28 	for (timeout = 1000; timeout > 0; timeout--) {
29 		if (snd_hdac_chip_readw(bus, CORBRP) == 0)
30 			break;
31 		udelay(1);
32 	}
33 	if (timeout <= 0)
34 		dev_err(bus->dev, "CORB reset timeout#2, CORBRP = %d\n",
35 			snd_hdac_chip_readw(bus, CORBRP));
36 }
37 
38 /**
39  * snd_hdac_bus_init_cmd_io - set up CORB/RIRB buffers
40  * @bus: HD-audio core bus
41  */
42 void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus)
43 {
44 	WARN_ON_ONCE(!bus->rb.area);
45 
46 	spin_lock_irq(&bus->reg_lock);
47 	/* CORB set up */
48 	bus->corb.addr = bus->rb.addr;
49 	bus->corb.buf = (__le32 *)bus->rb.area;
50 	snd_hdac_chip_writel(bus, CORBLBASE, (u32)bus->corb.addr);
51 	snd_hdac_chip_writel(bus, CORBUBASE, upper_32_bits(bus->corb.addr));
52 
53 	/* set the corb size to 256 entries (ULI requires explicitly) */
54 	snd_hdac_chip_writeb(bus, CORBSIZE, 0x02);
55 	/* set the corb write pointer to 0 */
56 	snd_hdac_chip_writew(bus, CORBWP, 0);
57 
58 	/* reset the corb hw read pointer */
59 	snd_hdac_chip_writew(bus, CORBRP, AZX_CORBRP_RST);
60 	if (!bus->corbrp_self_clear)
61 		azx_clear_corbrp(bus);
62 
63 	/* enable corb dma */
64 	snd_hdac_chip_writeb(bus, CORBCTL, AZX_CORBCTL_RUN);
65 
66 	/* RIRB set up */
67 	bus->rirb.addr = bus->rb.addr + 2048;
68 	bus->rirb.buf = (__le32 *)(bus->rb.area + 2048);
69 	bus->rirb.wp = bus->rirb.rp = 0;
70 	memset(bus->rirb.cmds, 0, sizeof(bus->rirb.cmds));
71 	snd_hdac_chip_writel(bus, RIRBLBASE, (u32)bus->rirb.addr);
72 	snd_hdac_chip_writel(bus, RIRBUBASE, upper_32_bits(bus->rirb.addr));
73 
74 	/* set the rirb size to 256 entries (ULI requires explicitly) */
75 	snd_hdac_chip_writeb(bus, RIRBSIZE, 0x02);
76 	/* reset the rirb hw write pointer */
77 	snd_hdac_chip_writew(bus, RIRBWP, AZX_RIRBWP_RST);
78 	/* set N=1, get RIRB response interrupt for new entry */
79 	snd_hdac_chip_writew(bus, RINTCNT, 1);
80 	/* enable rirb dma and response irq */
81 	snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN | AZX_RBCTL_IRQ_EN);
82 	/* Accept unsolicited responses */
83 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, AZX_GCTL_UNSOL);
84 	spin_unlock_irq(&bus->reg_lock);
85 }
86 EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io);
87 
88 /* wait for cmd dmas till they are stopped */
89 static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus)
90 {
91 	unsigned long timeout;
92 
93 	timeout = jiffies + msecs_to_jiffies(100);
94 	while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN)
95 		&& time_before(jiffies, timeout))
96 		udelay(10);
97 
98 	timeout = jiffies + msecs_to_jiffies(100);
99 	while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN)
100 		&& time_before(jiffies, timeout))
101 		udelay(10);
102 }
103 
104 /**
105  * snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers
106  * @bus: HD-audio core bus
107  */
108 void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus)
109 {
110 	spin_lock_irq(&bus->reg_lock);
111 	/* disable ringbuffer DMAs */
112 	snd_hdac_chip_writeb(bus, RIRBCTL, 0);
113 	snd_hdac_chip_writeb(bus, CORBCTL, 0);
114 	spin_unlock_irq(&bus->reg_lock);
115 
116 	hdac_wait_for_cmd_dmas(bus);
117 
118 	spin_lock_irq(&bus->reg_lock);
119 	/* disable unsolicited responses */
120 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0);
121 	spin_unlock_irq(&bus->reg_lock);
122 }
123 EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_cmd_io);
124 
125 static unsigned int azx_command_addr(u32 cmd)
126 {
127 	unsigned int addr = cmd >> 28;
128 
129 	if (snd_BUG_ON(addr >= HDA_MAX_CODECS))
130 		addr = 0;
131 	return addr;
132 }
133 
134 /**
135  * snd_hdac_bus_send_cmd - send a command verb via CORB
136  * @bus: HD-audio core bus
137  * @val: encoded verb value to send
138  *
139  * Returns zero for success or a negative error code.
140  */
141 int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val)
142 {
143 	unsigned int addr = azx_command_addr(val);
144 	unsigned int wp, rp;
145 
146 	spin_lock_irq(&bus->reg_lock);
147 
148 	bus->last_cmd[azx_command_addr(val)] = val;
149 
150 	/* add command to corb */
151 	wp = snd_hdac_chip_readw(bus, CORBWP);
152 	if (wp == 0xffff) {
153 		/* something wrong, controller likely turned to D3 */
154 		spin_unlock_irq(&bus->reg_lock);
155 		return -EIO;
156 	}
157 	wp++;
158 	wp %= AZX_MAX_CORB_ENTRIES;
159 
160 	rp = snd_hdac_chip_readw(bus, CORBRP);
161 	if (wp == rp) {
162 		/* oops, it's full */
163 		spin_unlock_irq(&bus->reg_lock);
164 		return -EAGAIN;
165 	}
166 
167 	bus->rirb.cmds[addr]++;
168 	bus->corb.buf[wp] = cpu_to_le32(val);
169 	snd_hdac_chip_writew(bus, CORBWP, wp);
170 
171 	spin_unlock_irq(&bus->reg_lock);
172 
173 	return 0;
174 }
175 EXPORT_SYMBOL_GPL(snd_hdac_bus_send_cmd);
176 
177 #define AZX_RIRB_EX_UNSOL_EV	(1<<4)
178 
179 /**
180  * snd_hdac_bus_update_rirb - retrieve RIRB entries
181  * @bus: HD-audio core bus
182  *
183  * Usually called from interrupt handler.
184  */
185 void snd_hdac_bus_update_rirb(struct hdac_bus *bus)
186 {
187 	unsigned int rp, wp;
188 	unsigned int addr;
189 	u32 res, res_ex;
190 
191 	wp = snd_hdac_chip_readw(bus, RIRBWP);
192 	if (wp == 0xffff) {
193 		/* something wrong, controller likely turned to D3 */
194 		return;
195 	}
196 
197 	if (wp == bus->rirb.wp)
198 		return;
199 	bus->rirb.wp = wp;
200 
201 	while (bus->rirb.rp != wp) {
202 		bus->rirb.rp++;
203 		bus->rirb.rp %= AZX_MAX_RIRB_ENTRIES;
204 
205 		rp = bus->rirb.rp << 1; /* an RIRB entry is 8-bytes */
206 		res_ex = le32_to_cpu(bus->rirb.buf[rp + 1]);
207 		res = le32_to_cpu(bus->rirb.buf[rp]);
208 		addr = res_ex & 0xf;
209 		if (addr >= HDA_MAX_CODECS) {
210 			dev_err(bus->dev,
211 				"spurious response %#x:%#x, rp = %d, wp = %d",
212 				res, res_ex, bus->rirb.rp, wp);
213 			snd_BUG();
214 		} else if (res_ex & AZX_RIRB_EX_UNSOL_EV)
215 			snd_hdac_bus_queue_event(bus, res, res_ex);
216 		else if (bus->rirb.cmds[addr]) {
217 			bus->rirb.res[addr] = res;
218 			bus->rirb.cmds[addr]--;
219 			if (!bus->rirb.cmds[addr] &&
220 			    waitqueue_active(&bus->rirb_wq))
221 				wake_up(&bus->rirb_wq);
222 		} else {
223 			dev_err_ratelimited(bus->dev,
224 				"spurious response %#x:%#x, last cmd=%#08x\n",
225 				res, res_ex, bus->last_cmd[addr]);
226 		}
227 	}
228 }
229 EXPORT_SYMBOL_GPL(snd_hdac_bus_update_rirb);
230 
231 /**
232  * snd_hdac_bus_get_response - receive a response via RIRB
233  * @bus: HD-audio core bus
234  * @addr: codec address
235  * @res: pointer to store the value, NULL when not needed
236  *
237  * Returns zero if a value is read, or a negative error code.
238  */
239 int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
240 			      unsigned int *res)
241 {
242 	unsigned long timeout;
243 	unsigned long loopcounter;
244 
245 	timeout = jiffies + msecs_to_jiffies(1000);
246 
247 	for (loopcounter = 0;; loopcounter++) {
248 		spin_lock_irq(&bus->reg_lock);
249 		if (bus->polling_mode)
250 			snd_hdac_bus_update_rirb(bus);
251 		if (!bus->rirb.cmds[addr]) {
252 			if (res)
253 				*res = bus->rirb.res[addr]; /* the last value */
254 			spin_unlock_irq(&bus->reg_lock);
255 			return 0;
256 		}
257 		spin_unlock_irq(&bus->reg_lock);
258 		if (time_after(jiffies, timeout))
259 			break;
260 		if (loopcounter > 3000)
261 			msleep(2); /* temporary workaround */
262 		else {
263 			udelay(10);
264 			cond_resched();
265 		}
266 	}
267 
268 	return -EIO;
269 }
270 EXPORT_SYMBOL_GPL(snd_hdac_bus_get_response);
271 
272 #define HDAC_MAX_CAPS 10
273 /**
274  * snd_hdac_bus_parse_capabilities - parse capability structure
275  * @bus: the pointer to bus object
276  *
277  * Returns 0 if successful, or a negative error code.
278  */
279 int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus)
280 {
281 	unsigned int cur_cap;
282 	unsigned int offset;
283 	unsigned int counter = 0;
284 
285 	offset = snd_hdac_chip_readw(bus, LLCH);
286 
287 	/* Lets walk the linked capabilities list */
288 	do {
289 		cur_cap = _snd_hdac_chip_readl(bus, offset);
290 
291 		dev_dbg(bus->dev, "Capability version: 0x%x\n",
292 			(cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF);
293 
294 		dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
295 			(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);
296 
297 		if (cur_cap == -1) {
298 			dev_dbg(bus->dev, "Invalid capability reg read\n");
299 			break;
300 		}
301 
302 		switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
303 		case AZX_ML_CAP_ID:
304 			dev_dbg(bus->dev, "Found ML capability\n");
305 			bus->mlcap = bus->remap_addr + offset;
306 			break;
307 
308 		case AZX_GTS_CAP_ID:
309 			dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
310 			bus->gtscap = bus->remap_addr + offset;
311 			break;
312 
313 		case AZX_PP_CAP_ID:
314 			/* PP capability found, the Audio DSP is present */
315 			dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
316 			bus->ppcap = bus->remap_addr + offset;
317 			break;
318 
319 		case AZX_SPB_CAP_ID:
320 			/* SPIB capability found, handler function */
321 			dev_dbg(bus->dev, "Found SPB capability\n");
322 			bus->spbcap = bus->remap_addr + offset;
323 			break;
324 
325 		case AZX_DRSM_CAP_ID:
326 			/* DMA resume  capability found, handler function */
327 			dev_dbg(bus->dev, "Found DRSM capability\n");
328 			bus->drsmcap = bus->remap_addr + offset;
329 			break;
330 
331 		default:
332 			dev_err(bus->dev, "Unknown capability %d\n", cur_cap);
333 			cur_cap = 0;
334 			break;
335 		}
336 
337 		counter++;
338 
339 		if (counter > HDAC_MAX_CAPS) {
340 			dev_err(bus->dev, "We exceeded HDAC capabilities!!!\n");
341 			break;
342 		}
343 
344 		/* read the offset of next capability */
345 		offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;
346 
347 	} while (offset);
348 
349 	return 0;
350 }
351 EXPORT_SYMBOL_GPL(snd_hdac_bus_parse_capabilities);
352 
353 /*
354  * Lowlevel interface
355  */
356 
357 /**
358  * snd_hdac_bus_enter_link_reset - enter link reset
359  * @bus: HD-audio core bus
360  *
361  * Enter to the link reset state.
362  */
363 void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus)
364 {
365 	unsigned long timeout;
366 
367 	/* reset controller */
368 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_RESET, 0);
369 
370 	timeout = jiffies + msecs_to_jiffies(100);
371 	while ((snd_hdac_chip_readb(bus, GCTL) & AZX_GCTL_RESET) &&
372 	       time_before(jiffies, timeout))
373 		usleep_range(500, 1000);
374 }
375 EXPORT_SYMBOL_GPL(snd_hdac_bus_enter_link_reset);
376 
377 /**
378  * snd_hdac_bus_exit_link_reset - exit link reset
379  * @bus: HD-audio core bus
380  *
381  * Exit from the link reset state.
382  */
383 void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus)
384 {
385 	unsigned long timeout;
386 
387 	snd_hdac_chip_updateb(bus, GCTL, AZX_GCTL_RESET, AZX_GCTL_RESET);
388 
389 	timeout = jiffies + msecs_to_jiffies(100);
390 	while (!snd_hdac_chip_readb(bus, GCTL) && time_before(jiffies, timeout))
391 		usleep_range(500, 1000);
392 }
393 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit_link_reset);
394 
395 /* reset codec link */
396 int snd_hdac_bus_reset_link(struct hdac_bus *bus, bool full_reset)
397 {
398 	if (!full_reset)
399 		goto skip_reset;
400 
401 	/* clear STATESTS */
402 	snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
403 
404 	/* reset controller */
405 	snd_hdac_bus_enter_link_reset(bus);
406 
407 	/* delay for >= 100us for codec PLL to settle per spec
408 	 * Rev 0.9 section 5.5.1
409 	 */
410 	usleep_range(500, 1000);
411 
412 	/* Bring controller out of reset */
413 	snd_hdac_bus_exit_link_reset(bus);
414 
415 	/* Brent Chartrand said to wait >= 540us for codecs to initialize */
416 	usleep_range(1000, 1200);
417 
418  skip_reset:
419 	/* check to see if controller is ready */
420 	if (!snd_hdac_chip_readb(bus, GCTL)) {
421 		dev_dbg(bus->dev, "controller not ready!\n");
422 		return -EBUSY;
423 	}
424 
425 	/* detect codecs */
426 	if (!bus->codec_mask) {
427 		bus->codec_mask = snd_hdac_chip_readw(bus, STATESTS);
428 		dev_dbg(bus->dev, "codec_mask = 0x%lx\n", bus->codec_mask);
429 	}
430 
431 	return 0;
432 }
433 EXPORT_SYMBOL_GPL(snd_hdac_bus_reset_link);
434 
435 /* enable interrupts */
436 static void azx_int_enable(struct hdac_bus *bus)
437 {
438 	/* enable controller CIE and GIE */
439 	snd_hdac_chip_updatel(bus, INTCTL,
440 			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN,
441 			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN);
442 }
443 
444 /* disable interrupts */
445 static void azx_int_disable(struct hdac_bus *bus)
446 {
447 	struct hdac_stream *azx_dev;
448 
449 	/* disable interrupts in stream descriptor */
450 	list_for_each_entry(azx_dev, &bus->stream_list, list)
451 		snd_hdac_stream_updateb(azx_dev, SD_CTL, SD_INT_MASK, 0);
452 
453 	/* disable SIE for all streams */
454 	snd_hdac_chip_writeb(bus, INTCTL, 0);
455 
456 	/* disable controller CIE and GIE */
457 	snd_hdac_chip_updatel(bus, INTCTL, AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN, 0);
458 }
459 
460 /* clear interrupts */
461 static void azx_int_clear(struct hdac_bus *bus)
462 {
463 	struct hdac_stream *azx_dev;
464 
465 	/* clear stream status */
466 	list_for_each_entry(azx_dev, &bus->stream_list, list)
467 		snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
468 
469 	/* clear STATESTS */
470 	snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
471 
472 	/* clear rirb status */
473 	snd_hdac_chip_writeb(bus, RIRBSTS, RIRB_INT_MASK);
474 
475 	/* clear int status */
476 	snd_hdac_chip_writel(bus, INTSTS, AZX_INT_CTRL_EN | AZX_INT_ALL_STREAM);
477 }
478 
479 /**
480  * snd_hdac_bus_init_chip - reset and start the controller registers
481  * @bus: HD-audio core bus
482  * @full_reset: Do full reset
483  */
484 bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset)
485 {
486 	if (bus->chip_init)
487 		return false;
488 
489 	/* reset controller */
490 	snd_hdac_bus_reset_link(bus, full_reset);
491 
492 	/* clear interrupts */
493 	azx_int_clear(bus);
494 
495 	/* initialize the codec command I/O */
496 	snd_hdac_bus_init_cmd_io(bus);
497 
498 	/* enable interrupts after CORB/RIRB buffers are initialized above */
499 	azx_int_enable(bus);
500 
501 	/* program the position buffer */
502 	if (bus->use_posbuf && bus->posbuf.addr) {
503 		snd_hdac_chip_writel(bus, DPLBASE, (u32)bus->posbuf.addr);
504 		snd_hdac_chip_writel(bus, DPUBASE, upper_32_bits(bus->posbuf.addr));
505 	}
506 
507 	bus->chip_init = true;
508 	return true;
509 }
510 EXPORT_SYMBOL_GPL(snd_hdac_bus_init_chip);
511 
512 /**
513  * snd_hdac_bus_stop_chip - disable the whole IRQ and I/Os
514  * @bus: HD-audio core bus
515  */
516 void snd_hdac_bus_stop_chip(struct hdac_bus *bus)
517 {
518 	if (!bus->chip_init)
519 		return;
520 
521 	/* disable interrupts */
522 	azx_int_disable(bus);
523 	azx_int_clear(bus);
524 
525 	/* disable CORB/RIRB */
526 	snd_hdac_bus_stop_cmd_io(bus);
527 
528 	/* disable position buffer */
529 	if (bus->posbuf.addr) {
530 		snd_hdac_chip_writel(bus, DPLBASE, 0);
531 		snd_hdac_chip_writel(bus, DPUBASE, 0);
532 	}
533 
534 	bus->chip_init = false;
535 }
536 EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_chip);
537 
538 /**
539  * snd_hdac_bus_handle_stream_irq - interrupt handler for streams
540  * @bus: HD-audio core bus
541  * @status: INTSTS register value
542  * @ask: callback to be called for woken streams
543  *
544  * Returns the bits of handled streams, or zero if no stream is handled.
545  */
546 int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
547 				    void (*ack)(struct hdac_bus *,
548 						struct hdac_stream *))
549 {
550 	struct hdac_stream *azx_dev;
551 	u8 sd_status;
552 	int handled = 0;
553 
554 	list_for_each_entry(azx_dev, &bus->stream_list, list) {
555 		if (status & azx_dev->sd_int_sta_mask) {
556 			sd_status = snd_hdac_stream_readb(azx_dev, SD_STS);
557 			snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
558 			handled |= 1 << azx_dev->index;
559 			if (!azx_dev->substream || !azx_dev->running ||
560 			    !(sd_status & SD_INT_COMPLETE))
561 				continue;
562 			if (ack)
563 				ack(bus, azx_dev);
564 		}
565 	}
566 	return handled;
567 }
568 EXPORT_SYMBOL_GPL(snd_hdac_bus_handle_stream_irq);
569 
570 /**
571  * snd_hdac_bus_alloc_stream_pages - allocate BDL and other buffers
572  * @bus: HD-audio core bus
573  *
574  * Call this after assigning the all streams.
575  * Returns zero for success, or a negative error code.
576  */
577 int snd_hdac_bus_alloc_stream_pages(struct hdac_bus *bus)
578 {
579 	struct hdac_stream *s;
580 	int num_streams = 0;
581 	int dma_type = bus->dma_type ? bus->dma_type : SNDRV_DMA_TYPE_DEV;
582 	int err;
583 
584 	list_for_each_entry(s, &bus->stream_list, list) {
585 		/* allocate memory for the BDL for each stream */
586 		err = snd_dma_alloc_pages(dma_type, bus->dev,
587 					  BDL_SIZE, &s->bdl);
588 		num_streams++;
589 		if (err < 0)
590 			return -ENOMEM;
591 	}
592 
593 	if (WARN_ON(!num_streams))
594 		return -EINVAL;
595 	/* allocate memory for the position buffer */
596 	err = snd_dma_alloc_pages(dma_type, bus->dev,
597 				  num_streams * 8, &bus->posbuf);
598 	if (err < 0)
599 		return -ENOMEM;
600 	list_for_each_entry(s, &bus->stream_list, list)
601 		s->posbuf = (__le32 *)(bus->posbuf.area + s->index * 8);
602 
603 	/* single page (at least 4096 bytes) must suffice for both ringbuffes */
604 	return snd_dma_alloc_pages(dma_type, bus->dev, PAGE_SIZE, &bus->rb);
605 }
606 EXPORT_SYMBOL_GPL(snd_hdac_bus_alloc_stream_pages);
607 
608 /**
609  * snd_hdac_bus_free_stream_pages - release BDL and other buffers
610  * @bus: HD-audio core bus
611  */
612 void snd_hdac_bus_free_stream_pages(struct hdac_bus *bus)
613 {
614 	struct hdac_stream *s;
615 
616 	list_for_each_entry(s, &bus->stream_list, list) {
617 		if (s->bdl.area)
618 			snd_dma_free_pages(&s->bdl);
619 	}
620 
621 	if (bus->rb.area)
622 		snd_dma_free_pages(&bus->rb);
623 	if (bus->posbuf.area)
624 		snd_dma_free_pages(&bus->posbuf);
625 }
626 EXPORT_SYMBOL_GPL(snd_hdac_bus_free_stream_pages);
627