xref: /openbmc/linux/sound/hda/hdac_controller.c (revision 3fc41476)
1 /*
2  * HD-audio controller helpers
3  */
4 
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/export.h>
8 #include <sound/core.h>
9 #include <sound/hdaudio.h>
10 #include <sound/hda_register.h>
11 
12 /* clear CORB read pointer properly */
13 static void azx_clear_corbrp(struct hdac_bus *bus)
14 {
15 	int timeout;
16 
17 	for (timeout = 1000; timeout > 0; timeout--) {
18 		if (snd_hdac_chip_readw(bus, CORBRP) & AZX_CORBRP_RST)
19 			break;
20 		udelay(1);
21 	}
22 	if (timeout <= 0)
23 		dev_err(bus->dev, "CORB reset timeout#1, CORBRP = %d\n",
24 			snd_hdac_chip_readw(bus, CORBRP));
25 
26 	snd_hdac_chip_writew(bus, CORBRP, 0);
27 	for (timeout = 1000; timeout > 0; timeout--) {
28 		if (snd_hdac_chip_readw(bus, CORBRP) == 0)
29 			break;
30 		udelay(1);
31 	}
32 	if (timeout <= 0)
33 		dev_err(bus->dev, "CORB reset timeout#2, CORBRP = %d\n",
34 			snd_hdac_chip_readw(bus, CORBRP));
35 }
36 
37 /**
38  * snd_hdac_bus_init_cmd_io - set up CORB/RIRB buffers
39  * @bus: HD-audio core bus
40  */
41 void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus)
42 {
43 	WARN_ON_ONCE(!bus->rb.area);
44 
45 	spin_lock_irq(&bus->reg_lock);
46 	/* CORB set up */
47 	bus->corb.addr = bus->rb.addr;
48 	bus->corb.buf = (__le32 *)bus->rb.area;
49 	snd_hdac_chip_writel(bus, CORBLBASE, (u32)bus->corb.addr);
50 	snd_hdac_chip_writel(bus, CORBUBASE, upper_32_bits(bus->corb.addr));
51 
52 	/* set the corb size to 256 entries (ULI requires explicitly) */
53 	snd_hdac_chip_writeb(bus, CORBSIZE, 0x02);
54 	/* set the corb write pointer to 0 */
55 	snd_hdac_chip_writew(bus, CORBWP, 0);
56 
57 	/* reset the corb hw read pointer */
58 	snd_hdac_chip_writew(bus, CORBRP, AZX_CORBRP_RST);
59 	if (!bus->corbrp_self_clear)
60 		azx_clear_corbrp(bus);
61 
62 	/* enable corb dma */
63 	snd_hdac_chip_writeb(bus, CORBCTL, AZX_CORBCTL_RUN);
64 
65 	/* RIRB set up */
66 	bus->rirb.addr = bus->rb.addr + 2048;
67 	bus->rirb.buf = (__le32 *)(bus->rb.area + 2048);
68 	bus->rirb.wp = bus->rirb.rp = 0;
69 	memset(bus->rirb.cmds, 0, sizeof(bus->rirb.cmds));
70 	snd_hdac_chip_writel(bus, RIRBLBASE, (u32)bus->rirb.addr);
71 	snd_hdac_chip_writel(bus, RIRBUBASE, upper_32_bits(bus->rirb.addr));
72 
73 	/* set the rirb size to 256 entries (ULI requires explicitly) */
74 	snd_hdac_chip_writeb(bus, RIRBSIZE, 0x02);
75 	/* reset the rirb hw write pointer */
76 	snd_hdac_chip_writew(bus, RIRBWP, AZX_RIRBWP_RST);
77 	/* set N=1, get RIRB response interrupt for new entry */
78 	snd_hdac_chip_writew(bus, RINTCNT, 1);
79 	/* enable rirb dma and response irq */
80 	snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN | AZX_RBCTL_IRQ_EN);
81 	spin_unlock_irq(&bus->reg_lock);
82 }
83 EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io);
84 
85 /* wait for cmd dmas till they are stopped */
86 static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus)
87 {
88 	unsigned long timeout;
89 
90 	timeout = jiffies + msecs_to_jiffies(100);
91 	while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN)
92 		&& time_before(jiffies, timeout))
93 		udelay(10);
94 
95 	timeout = jiffies + msecs_to_jiffies(100);
96 	while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN)
97 		&& time_before(jiffies, timeout))
98 		udelay(10);
99 }
100 
101 /**
102  * snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers
103  * @bus: HD-audio core bus
104  */
105 void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus)
106 {
107 	spin_lock_irq(&bus->reg_lock);
108 	/* disable ringbuffer DMAs */
109 	snd_hdac_chip_writeb(bus, RIRBCTL, 0);
110 	snd_hdac_chip_writeb(bus, CORBCTL, 0);
111 	spin_unlock_irq(&bus->reg_lock);
112 
113 	hdac_wait_for_cmd_dmas(bus);
114 
115 	spin_lock_irq(&bus->reg_lock);
116 	/* disable unsolicited responses */
117 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0);
118 	spin_unlock_irq(&bus->reg_lock);
119 }
120 EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_cmd_io);
121 
122 static unsigned int azx_command_addr(u32 cmd)
123 {
124 	unsigned int addr = cmd >> 28;
125 
126 	if (snd_BUG_ON(addr >= HDA_MAX_CODECS))
127 		addr = 0;
128 	return addr;
129 }
130 
131 /**
132  * snd_hdac_bus_send_cmd - send a command verb via CORB
133  * @bus: HD-audio core bus
134  * @val: encoded verb value to send
135  *
136  * Returns zero for success or a negative error code.
137  */
138 int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val)
139 {
140 	unsigned int addr = azx_command_addr(val);
141 	unsigned int wp, rp;
142 
143 	spin_lock_irq(&bus->reg_lock);
144 
145 	bus->last_cmd[azx_command_addr(val)] = val;
146 
147 	/* add command to corb */
148 	wp = snd_hdac_chip_readw(bus, CORBWP);
149 	if (wp == 0xffff) {
150 		/* something wrong, controller likely turned to D3 */
151 		spin_unlock_irq(&bus->reg_lock);
152 		return -EIO;
153 	}
154 	wp++;
155 	wp %= AZX_MAX_CORB_ENTRIES;
156 
157 	rp = snd_hdac_chip_readw(bus, CORBRP);
158 	if (wp == rp) {
159 		/* oops, it's full */
160 		spin_unlock_irq(&bus->reg_lock);
161 		return -EAGAIN;
162 	}
163 
164 	bus->rirb.cmds[addr]++;
165 	bus->corb.buf[wp] = cpu_to_le32(val);
166 	snd_hdac_chip_writew(bus, CORBWP, wp);
167 
168 	spin_unlock_irq(&bus->reg_lock);
169 
170 	return 0;
171 }
172 EXPORT_SYMBOL_GPL(snd_hdac_bus_send_cmd);
173 
174 #define AZX_RIRB_EX_UNSOL_EV	(1<<4)
175 
176 /**
177  * snd_hdac_bus_update_rirb - retrieve RIRB entries
178  * @bus: HD-audio core bus
179  *
180  * Usually called from interrupt handler.
181  */
182 void snd_hdac_bus_update_rirb(struct hdac_bus *bus)
183 {
184 	unsigned int rp, wp;
185 	unsigned int addr;
186 	u32 res, res_ex;
187 
188 	wp = snd_hdac_chip_readw(bus, RIRBWP);
189 	if (wp == 0xffff) {
190 		/* something wrong, controller likely turned to D3 */
191 		return;
192 	}
193 
194 	if (wp == bus->rirb.wp)
195 		return;
196 	bus->rirb.wp = wp;
197 
198 	while (bus->rirb.rp != wp) {
199 		bus->rirb.rp++;
200 		bus->rirb.rp %= AZX_MAX_RIRB_ENTRIES;
201 
202 		rp = bus->rirb.rp << 1; /* an RIRB entry is 8-bytes */
203 		res_ex = le32_to_cpu(bus->rirb.buf[rp + 1]);
204 		res = le32_to_cpu(bus->rirb.buf[rp]);
205 		addr = res_ex & 0xf;
206 		if (addr >= HDA_MAX_CODECS) {
207 			dev_err(bus->dev,
208 				"spurious response %#x:%#x, rp = %d, wp = %d",
209 				res, res_ex, bus->rirb.rp, wp);
210 			snd_BUG();
211 		} else if (res_ex & AZX_RIRB_EX_UNSOL_EV)
212 			snd_hdac_bus_queue_event(bus, res, res_ex);
213 		else if (bus->rirb.cmds[addr]) {
214 			bus->rirb.res[addr] = res;
215 			bus->rirb.cmds[addr]--;
216 		} else {
217 			dev_err_ratelimited(bus->dev,
218 				"spurious response %#x:%#x, last cmd=%#08x\n",
219 				res, res_ex, bus->last_cmd[addr]);
220 		}
221 	}
222 }
223 EXPORT_SYMBOL_GPL(snd_hdac_bus_update_rirb);
224 
225 /**
226  * snd_hdac_bus_get_response - receive a response via RIRB
227  * @bus: HD-audio core bus
228  * @addr: codec address
229  * @res: pointer to store the value, NULL when not needed
230  *
231  * Returns zero if a value is read, or a negative error code.
232  */
233 int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
234 			      unsigned int *res)
235 {
236 	unsigned long timeout;
237 	unsigned long loopcounter;
238 
239 	timeout = jiffies + msecs_to_jiffies(1000);
240 
241 	for (loopcounter = 0;; loopcounter++) {
242 		spin_lock_irq(&bus->reg_lock);
243 		if (bus->polling_mode)
244 			snd_hdac_bus_update_rirb(bus);
245 		if (!bus->rirb.cmds[addr]) {
246 			if (res)
247 				*res = bus->rirb.res[addr]; /* the last value */
248 			spin_unlock_irq(&bus->reg_lock);
249 			return 0;
250 		}
251 		spin_unlock_irq(&bus->reg_lock);
252 		if (time_after(jiffies, timeout))
253 			break;
254 		if (loopcounter > 3000)
255 			msleep(2); /* temporary workaround */
256 		else {
257 			udelay(10);
258 			cond_resched();
259 		}
260 	}
261 
262 	return -EIO;
263 }
264 EXPORT_SYMBOL_GPL(snd_hdac_bus_get_response);
265 
266 #define HDAC_MAX_CAPS 10
267 /**
268  * snd_hdac_bus_parse_capabilities - parse capability structure
269  * @bus: the pointer to bus object
270  *
271  * Returns 0 if successful, or a negative error code.
272  */
273 int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus)
274 {
275 	unsigned int cur_cap;
276 	unsigned int offset;
277 	unsigned int counter = 0;
278 
279 	offset = snd_hdac_chip_readw(bus, LLCH);
280 
281 	/* Lets walk the linked capabilities list */
282 	do {
283 		cur_cap = _snd_hdac_chip_readl(bus, offset);
284 
285 		dev_dbg(bus->dev, "Capability version: 0x%x\n",
286 			(cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF);
287 
288 		dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
289 			(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);
290 
291 		if (cur_cap == -1) {
292 			dev_dbg(bus->dev, "Invalid capability reg read\n");
293 			break;
294 		}
295 
296 		switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
297 		case AZX_ML_CAP_ID:
298 			dev_dbg(bus->dev, "Found ML capability\n");
299 			bus->mlcap = bus->remap_addr + offset;
300 			break;
301 
302 		case AZX_GTS_CAP_ID:
303 			dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
304 			bus->gtscap = bus->remap_addr + offset;
305 			break;
306 
307 		case AZX_PP_CAP_ID:
308 			/* PP capability found, the Audio DSP is present */
309 			dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
310 			bus->ppcap = bus->remap_addr + offset;
311 			break;
312 
313 		case AZX_SPB_CAP_ID:
314 			/* SPIB capability found, handler function */
315 			dev_dbg(bus->dev, "Found SPB capability\n");
316 			bus->spbcap = bus->remap_addr + offset;
317 			break;
318 
319 		case AZX_DRSM_CAP_ID:
320 			/* DMA resume  capability found, handler function */
321 			dev_dbg(bus->dev, "Found DRSM capability\n");
322 			bus->drsmcap = bus->remap_addr + offset;
323 			break;
324 
325 		default:
326 			dev_err(bus->dev, "Unknown capability %d\n", cur_cap);
327 			cur_cap = 0;
328 			break;
329 		}
330 
331 		counter++;
332 
333 		if (counter > HDAC_MAX_CAPS) {
334 			dev_err(bus->dev, "We exceeded HDAC capabilities!!!\n");
335 			break;
336 		}
337 
338 		/* read the offset of next capability */
339 		offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;
340 
341 	} while (offset);
342 
343 	return 0;
344 }
345 EXPORT_SYMBOL_GPL(snd_hdac_bus_parse_capabilities);
346 
347 /*
348  * Lowlevel interface
349  */
350 
351 /**
352  * snd_hdac_bus_enter_link_reset - enter link reset
353  * @bus: HD-audio core bus
354  *
355  * Enter to the link reset state.
356  */
357 void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus)
358 {
359 	unsigned long timeout;
360 
361 	/* reset controller */
362 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_RESET, 0);
363 
364 	timeout = jiffies + msecs_to_jiffies(100);
365 	while ((snd_hdac_chip_readb(bus, GCTL) & AZX_GCTL_RESET) &&
366 	       time_before(jiffies, timeout))
367 		usleep_range(500, 1000);
368 }
369 EXPORT_SYMBOL_GPL(snd_hdac_bus_enter_link_reset);
370 
371 /**
372  * snd_hdac_bus_exit_link_reset - exit link reset
373  * @bus: HD-audio core bus
374  *
375  * Exit from the link reset state.
376  */
377 void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus)
378 {
379 	unsigned long timeout;
380 
381 	snd_hdac_chip_updateb(bus, GCTL, AZX_GCTL_RESET, AZX_GCTL_RESET);
382 
383 	timeout = jiffies + msecs_to_jiffies(100);
384 	while (!snd_hdac_chip_readb(bus, GCTL) && time_before(jiffies, timeout))
385 		usleep_range(500, 1000);
386 }
387 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit_link_reset);
388 
389 /* reset codec link */
390 int snd_hdac_bus_reset_link(struct hdac_bus *bus, bool full_reset)
391 {
392 	if (!full_reset)
393 		goto skip_reset;
394 
395 	/* clear STATESTS */
396 	snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
397 
398 	/* reset controller */
399 	snd_hdac_bus_enter_link_reset(bus);
400 
401 	/* delay for >= 100us for codec PLL to settle per spec
402 	 * Rev 0.9 section 5.5.1
403 	 */
404 	usleep_range(500, 1000);
405 
406 	/* Bring controller out of reset */
407 	snd_hdac_bus_exit_link_reset(bus);
408 
409 	/* Brent Chartrand said to wait >= 540us for codecs to initialize */
410 	usleep_range(1000, 1200);
411 
412  skip_reset:
413 	/* check to see if controller is ready */
414 	if (!snd_hdac_chip_readb(bus, GCTL)) {
415 		dev_dbg(bus->dev, "controller not ready!\n");
416 		return -EBUSY;
417 	}
418 
419 	/* Accept unsolicited responses */
420 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, AZX_GCTL_UNSOL);
421 
422 	/* detect codecs */
423 	if (!bus->codec_mask) {
424 		bus->codec_mask = snd_hdac_chip_readw(bus, STATESTS);
425 		dev_dbg(bus->dev, "codec_mask = 0x%lx\n", bus->codec_mask);
426 	}
427 
428 	return 0;
429 }
430 EXPORT_SYMBOL_GPL(snd_hdac_bus_reset_link);
431 
432 /* enable interrupts */
433 static void azx_int_enable(struct hdac_bus *bus)
434 {
435 	/* enable controller CIE and GIE */
436 	snd_hdac_chip_updatel(bus, INTCTL,
437 			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN,
438 			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN);
439 }
440 
441 /* disable interrupts */
442 static void azx_int_disable(struct hdac_bus *bus)
443 {
444 	struct hdac_stream *azx_dev;
445 
446 	/* disable interrupts in stream descriptor */
447 	list_for_each_entry(azx_dev, &bus->stream_list, list)
448 		snd_hdac_stream_updateb(azx_dev, SD_CTL, SD_INT_MASK, 0);
449 
450 	/* disable SIE for all streams */
451 	snd_hdac_chip_writeb(bus, INTCTL, 0);
452 
453 	/* disable controller CIE and GIE */
454 	snd_hdac_chip_updatel(bus, INTCTL, AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN, 0);
455 }
456 
457 /* clear interrupts */
458 static void azx_int_clear(struct hdac_bus *bus)
459 {
460 	struct hdac_stream *azx_dev;
461 
462 	/* clear stream status */
463 	list_for_each_entry(azx_dev, &bus->stream_list, list)
464 		snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
465 
466 	/* clear STATESTS */
467 	snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
468 
469 	/* clear rirb status */
470 	snd_hdac_chip_writeb(bus, RIRBSTS, RIRB_INT_MASK);
471 
472 	/* clear int status */
473 	snd_hdac_chip_writel(bus, INTSTS, AZX_INT_CTRL_EN | AZX_INT_ALL_STREAM);
474 }
475 
476 /**
477  * snd_hdac_bus_init_chip - reset and start the controller registers
478  * @bus: HD-audio core bus
479  * @full_reset: Do full reset
480  */
481 bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset)
482 {
483 	if (bus->chip_init)
484 		return false;
485 
486 	/* reset controller */
487 	snd_hdac_bus_reset_link(bus, full_reset);
488 
489 	/* clear interrupts */
490 	azx_int_clear(bus);
491 
492 	/* initialize the codec command I/O */
493 	snd_hdac_bus_init_cmd_io(bus);
494 
495 	/* enable interrupts after CORB/RIRB buffers are initialized above */
496 	azx_int_enable(bus);
497 
498 	/* program the position buffer */
499 	if (bus->use_posbuf && bus->posbuf.addr) {
500 		snd_hdac_chip_writel(bus, DPLBASE, (u32)bus->posbuf.addr);
501 		snd_hdac_chip_writel(bus, DPUBASE, upper_32_bits(bus->posbuf.addr));
502 	}
503 
504 	bus->chip_init = true;
505 	return true;
506 }
507 EXPORT_SYMBOL_GPL(snd_hdac_bus_init_chip);
508 
509 /**
510  * snd_hdac_bus_stop_chip - disable the whole IRQ and I/Os
511  * @bus: HD-audio core bus
512  */
513 void snd_hdac_bus_stop_chip(struct hdac_bus *bus)
514 {
515 	if (!bus->chip_init)
516 		return;
517 
518 	/* disable interrupts */
519 	azx_int_disable(bus);
520 	azx_int_clear(bus);
521 
522 	/* disable CORB/RIRB */
523 	snd_hdac_bus_stop_cmd_io(bus);
524 
525 	/* disable position buffer */
526 	if (bus->posbuf.addr) {
527 		snd_hdac_chip_writel(bus, DPLBASE, 0);
528 		snd_hdac_chip_writel(bus, DPUBASE, 0);
529 	}
530 
531 	bus->chip_init = false;
532 }
533 EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_chip);
534 
535 /**
536  * snd_hdac_bus_handle_stream_irq - interrupt handler for streams
537  * @bus: HD-audio core bus
538  * @status: INTSTS register value
539  * @ask: callback to be called for woken streams
540  *
541  * Returns the bits of handled streams, or zero if no stream is handled.
542  */
543 int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
544 				    void (*ack)(struct hdac_bus *,
545 						struct hdac_stream *))
546 {
547 	struct hdac_stream *azx_dev;
548 	u8 sd_status;
549 	int handled = 0;
550 
551 	list_for_each_entry(azx_dev, &bus->stream_list, list) {
552 		if (status & azx_dev->sd_int_sta_mask) {
553 			sd_status = snd_hdac_stream_readb(azx_dev, SD_STS);
554 			snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
555 			handled |= 1 << azx_dev->index;
556 			if (!azx_dev->substream || !azx_dev->running ||
557 			    !(sd_status & SD_INT_COMPLETE))
558 				continue;
559 			if (ack)
560 				ack(bus, azx_dev);
561 		}
562 	}
563 	return handled;
564 }
565 EXPORT_SYMBOL_GPL(snd_hdac_bus_handle_stream_irq);
566 
567 /**
568  * snd_hdac_bus_alloc_stream_pages - allocate BDL and other buffers
569  * @bus: HD-audio core bus
570  *
571  * Call this after assigning the all streams.
572  * Returns zero for success, or a negative error code.
573  */
574 int snd_hdac_bus_alloc_stream_pages(struct hdac_bus *bus)
575 {
576 	struct hdac_stream *s;
577 	int num_streams = 0;
578 	int err;
579 
580 	list_for_each_entry(s, &bus->stream_list, list) {
581 		/* allocate memory for the BDL for each stream */
582 		err = bus->io_ops->dma_alloc_pages(bus, SNDRV_DMA_TYPE_DEV,
583 						   BDL_SIZE, &s->bdl);
584 		num_streams++;
585 		if (err < 0)
586 			return -ENOMEM;
587 	}
588 
589 	if (WARN_ON(!num_streams))
590 		return -EINVAL;
591 	/* allocate memory for the position buffer */
592 	err = bus->io_ops->dma_alloc_pages(bus, SNDRV_DMA_TYPE_DEV,
593 					   num_streams * 8, &bus->posbuf);
594 	if (err < 0)
595 		return -ENOMEM;
596 	list_for_each_entry(s, &bus->stream_list, list)
597 		s->posbuf = (__le32 *)(bus->posbuf.area + s->index * 8);
598 
599 	/* single page (at least 4096 bytes) must suffice for both ringbuffes */
600 	return bus->io_ops->dma_alloc_pages(bus, SNDRV_DMA_TYPE_DEV,
601 					    PAGE_SIZE, &bus->rb);
602 }
603 EXPORT_SYMBOL_GPL(snd_hdac_bus_alloc_stream_pages);
604 
605 /**
606  * snd_hdac_bus_free_stream_pages - release BDL and other buffers
607  * @bus: HD-audio core bus
608  */
609 void snd_hdac_bus_free_stream_pages(struct hdac_bus *bus)
610 {
611 	struct hdac_stream *s;
612 
613 	list_for_each_entry(s, &bus->stream_list, list) {
614 		if (s->bdl.area)
615 			bus->io_ops->dma_free_pages(bus, &s->bdl);
616 	}
617 
618 	if (bus->rb.area)
619 		bus->io_ops->dma_free_pages(bus, &bus->rb);
620 	if (bus->posbuf.area)
621 		bus->io_ops->dma_free_pages(bus, &bus->posbuf);
622 }
623 EXPORT_SYMBOL_GPL(snd_hdac_bus_free_stream_pages);
624