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#include "local.h"
13#include "../pci/hda/hda_controller.h"
14
15/* clear CORB read pointer properly */
16static void azx_clear_corbrp(struct hdac_bus *bus)
17{
18	int timeout;
19
20	for (timeout = 1000; timeout > 0; timeout--) {
21		if (snd_hdac_chip_readw(bus, CORBRP) & AZX_CORBRP_RST)
22			break;
23		udelay(1);
24	}
25	if (timeout <= 0)
26		dev_err(bus->dev, "CORB reset timeout#1, CORBRP = %d\n",
27			snd_hdac_chip_readw(bus, CORBRP));
28
29	snd_hdac_chip_writew(bus, CORBRP, 0);
30	for (timeout = 1000; timeout > 0; timeout--) {
31		if (snd_hdac_chip_readw(bus, CORBRP) == 0)
32			break;
33		udelay(1);
34	}
35	if (timeout <= 0)
36		dev_err(bus->dev, "CORB reset timeout#2, CORBRP = %d\n",
37			snd_hdac_chip_readw(bus, CORBRP));
38}
39
40/**
41 * snd_hdac_bus_init_cmd_io - set up CORB/RIRB buffers
42 * @bus: HD-audio core bus
43 */
44void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus)
45{
46	struct azx *chip = bus_to_azx(bus);
47
48	WARN_ON_ONCE(!bus->rb.area);
49
50	spin_lock_irq(&bus->reg_lock);
51	/* CORB set up */
52	bus->corb.addr = bus->rb.addr;
53	bus->corb.buf = (__le32 *)bus->rb.area;
54	snd_hdac_chip_writel(bus, CORBLBASE, (u32)bus->corb.addr);
55	snd_hdac_chip_writel(bus, CORBUBASE, upper_32_bits(bus->corb.addr));
56
57	/* set the corb size to 256 entries (ULI requires explicitly) */
58	snd_hdac_chip_writeb(bus, CORBSIZE, 0x02);
59	/* set the corb write pointer to 0 */
60	snd_hdac_chip_writew(bus, CORBWP, 0);
61
62	/* reset the corb hw read pointer */
63	snd_hdac_chip_writew(bus, CORBRP, AZX_CORBRP_RST);
64	if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND)
65		snd_hdac_chip_writew(bus, CORBRP, 0);
66	else if (!bus->corbrp_self_clear)
67		azx_clear_corbrp(bus);
68
69	/* enable corb dma */
70	snd_hdac_chip_writeb(bus, CORBCTL, AZX_CORBCTL_RUN);
71	if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND)
72		snd_hdac_chip_readb(bus, CORBCTL);
73
74	/* RIRB set up */
75	bus->rirb.addr = bus->rb.addr + 2048;
76	bus->rirb.buf = (__le32 *)(bus->rb.area + 2048);
77	bus->rirb.wp = bus->rirb.rp = 0;
78	memset(bus->rirb.cmds, 0, sizeof(bus->rirb.cmds));
79	snd_hdac_chip_writel(bus, RIRBLBASE, (u32)bus->rirb.addr);
80	snd_hdac_chip_writel(bus, RIRBUBASE, upper_32_bits(bus->rirb.addr));
81
82	/* set the rirb size to 256 entries (ULI requires explicitly) */
83	snd_hdac_chip_writeb(bus, RIRBSIZE, 0x02);
84	/* reset the rirb hw write pointer */
85	snd_hdac_chip_writew(bus, RIRBWP, AZX_RIRBWP_RST);
86	/* set N=1, get RIRB response interrupt for new entry */
87	snd_hdac_chip_writew(bus, RINTCNT, 1);
88	/* enable rirb dma and response irq */
89	if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND) {
90		snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN);
91		snd_hdac_chip_readb(bus, RIRBCTL);
92	}
93	else
94		snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN | AZX_RBCTL_IRQ_EN);
95	/* Accept unsolicited responses */
96	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, AZX_GCTL_UNSOL);
97	spin_unlock_irq(&bus->reg_lock);
98}
99EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io);
100
101/* wait for cmd dmas till they are stopped */
102static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus)
103{
104	unsigned long timeout;
105
106	timeout = jiffies + msecs_to_jiffies(100);
107	while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN)
108		&& time_before(jiffies, timeout))
109		udelay(10);
110
111	timeout = jiffies + msecs_to_jiffies(100);
112	while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN)
113		&& time_before(jiffies, timeout))
114		udelay(10);
115}
116
117/**
118 * snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers
119 * @bus: HD-audio core bus
120 */
121void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus)
122{
123	spin_lock_irq(&bus->reg_lock);
124	/* disable ringbuffer DMAs */
125	snd_hdac_chip_writeb(bus, RIRBCTL, 0);
126	snd_hdac_chip_writeb(bus, CORBCTL, 0);
127	spin_unlock_irq(&bus->reg_lock);
128
129	hdac_wait_for_cmd_dmas(bus);
130
131	spin_lock_irq(&bus->reg_lock);
132	/* disable unsolicited responses */
133	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0);
134	spin_unlock_irq(&bus->reg_lock);
135}
136EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_cmd_io);
137
138static unsigned int azx_command_addr(u32 cmd)
139{
140	unsigned int addr = cmd >> 28;
141
142	if (snd_BUG_ON(addr >= HDA_MAX_CODECS))
143		addr = 0;
144	return addr;
145}
146
147static unsigned int azx_response_addr(u32 res)
148{
149	unsigned int addr = res & 0xf;
150
151	if (addr >= AZX_MAX_CODECS) {
152		snd_BUG();
153		addr = 0;
154	}
155
156	return addr;
157}
158
159/**
160 * snd_hdac_bus_send_cmd - send a command verb via CORB
161 * @bus: HD-audio core bus
162 * @val: encoded verb value to send
163 *
164 * Returns zero for success or a negative error code.
165 */
166int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val)
167{
168	unsigned int addr = azx_command_addr(val);
169	unsigned int wp, rp;
170
171	spin_lock_irq(&bus->reg_lock);
172
173	bus->last_cmd[azx_command_addr(val)] = val;
174
175	/* add command to corb */
176	wp = snd_hdac_chip_readw(bus, CORBWP);
177	if (wp == 0xffff) {
178		/* something wrong, controller likely turned to D3 */
179		spin_unlock_irq(&bus->reg_lock);
180		return -EIO;
181	}
182	wp++;
183	wp %= AZX_MAX_CORB_ENTRIES;
184
185	rp = snd_hdac_chip_readw(bus, CORBRP);
186	if (wp == rp) {
187		/* oops, it's full */
188		spin_unlock_irq(&bus->reg_lock);
189		return -EAGAIN;
190	}
191
192	bus->rirb.cmds[addr]++;
193	bus->corb.buf[wp] = cpu_to_le32(val);
194	snd_hdac_chip_writew(bus, CORBWP, wp);
195
196	spin_unlock_irq(&bus->reg_lock);
197
198	return 0;
199}
200EXPORT_SYMBOL_GPL(snd_hdac_bus_send_cmd);
201
202#define AZX_RIRB_EX_UNSOL_EV	(1<<4)
203
204/**
205 * snd_hdac_bus_update_rirb - retrieve RIRB entries
206 * @bus: HD-audio core bus
207 *
208 * Usually called from interrupt handler.
209 * The caller needs bus->reg_lock spinlock before calling this.
210 */
211void snd_hdac_bus_update_rirb(struct hdac_bus *bus)
212{
213	unsigned int rp, wp;
214	unsigned int addr;
215	u32 res, res_ex;
216
217	wp = snd_hdac_chip_readw(bus, RIRBWP);
218	if (wp == 0xffff) {
219		/* something wrong, controller likely turned to D3 */
220		return;
221	}
222
223	if (wp == bus->rirb.wp)
224		return;
225	bus->rirb.wp = wp;
226
227	while (bus->rirb.rp != wp) {
228		bus->rirb.rp++;
229		bus->rirb.rp %= AZX_MAX_RIRB_ENTRIES;
230
231		rp = bus->rirb.rp << 1; /* an RIRB entry is 8-bytes */
232		res_ex = le32_to_cpu(bus->rirb.buf[rp + 1]);
233		res = le32_to_cpu(bus->rirb.buf[rp]);
234		addr = azx_response_addr(res_ex);
235		if (res_ex & AZX_RIRB_EX_UNSOL_EV)
236			snd_hdac_bus_queue_event(bus, res, res_ex);
237		else if (bus->rirb.cmds[addr]) {
238			bus->rirb.res[addr] = res;
239			bus->rirb.cmds[addr]--;
240			if (!bus->rirb.cmds[addr] &&
241			    waitqueue_active(&bus->rirb_wq))
242				wake_up(&bus->rirb_wq);
243		} else {
244			dev_err_ratelimited(bus->dev,
245				"spurious response %#x:%#x, last cmd=%#08x\n",
246				res, res_ex, bus->last_cmd[addr]);
247		}
248	}
249}
250EXPORT_SYMBOL_GPL(snd_hdac_bus_update_rirb);
251
252/**
253 * snd_hdac_bus_get_response - receive a response via RIRB
254 * @bus: HD-audio core bus
255 * @addr: codec address
256 * @res: pointer to store the value, NULL when not needed
257 *
258 * Returns zero if a value is read, or a negative error code.
259 */
260int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
261			      unsigned int *res)
262{
263	unsigned long timeout;
264	unsigned long loopcounter;
265	wait_queue_entry_t wait;
266	bool warned = false;
267
268	init_wait_entry(&wait, 0);
269	timeout = jiffies + msecs_to_jiffies(1000);
270
271	for (loopcounter = 0;; loopcounter++) {
272		spin_lock_irq(&bus->reg_lock);
273		if (!bus->polling_mode)
274			prepare_to_wait(&bus->rirb_wq, &wait,
275					TASK_UNINTERRUPTIBLE);
276		if (bus->polling_mode)
277			snd_hdac_bus_update_rirb(bus);
278		if (!bus->rirb.cmds[addr]) {
279			if (res)
280				*res = bus->rirb.res[addr]; /* the last value */
281			if (!bus->polling_mode)
282				finish_wait(&bus->rirb_wq, &wait);
283			spin_unlock_irq(&bus->reg_lock);
284			return 0;
285		}
286		spin_unlock_irq(&bus->reg_lock);
287		if (time_after(jiffies, timeout))
288			break;
289#define LOOP_COUNT_MAX	3000
290		if (!bus->polling_mode) {
291			schedule_timeout(msecs_to_jiffies(2));
292		} else if (bus->needs_damn_long_delay ||
293			   loopcounter > LOOP_COUNT_MAX) {
294			if (loopcounter > LOOP_COUNT_MAX && !warned) {
295				dev_dbg_ratelimited(bus->dev,
296						    "too slow response, last cmd=%#08x\n",
297						    bus->last_cmd[addr]);
298				warned = true;
299			}
300			msleep(2); /* temporary workaround */
301		} else {
302			udelay(10);
303			cond_resched();
304		}
305	}
306
307	if (!bus->polling_mode)
308		finish_wait(&bus->rirb_wq, &wait);
309
310	return -EIO;
311}
312EXPORT_SYMBOL_GPL(snd_hdac_bus_get_response);
313
314#define HDAC_MAX_CAPS 10
315/**
316 * snd_hdac_bus_parse_capabilities - parse capability structure
317 * @bus: the pointer to bus object
318 *
319 * Returns 0 if successful, or a negative error code.
320 */
321int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus)
322{
323	unsigned int cur_cap;
324	unsigned int offset;
325	unsigned int counter = 0;
326
327	offset = snd_hdac_chip_readw(bus, LLCH);
328
329	/* Lets walk the linked capabilities list */
330	do {
331		cur_cap = _snd_hdac_chip_readl(bus, offset);
332
333		dev_dbg(bus->dev, "Capability version: 0x%x\n",
334			(cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF);
335
336		dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
337			(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);
338
339		if (cur_cap == -1) {
340			dev_dbg(bus->dev, "Invalid capability reg read\n");
341			break;
342		}
343
344		switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
345		case AZX_ML_CAP_ID:
346			dev_dbg(bus->dev, "Found ML capability\n");
347			bus->mlcap = bus->remap_addr + offset;
348			break;
349
350		case AZX_GTS_CAP_ID:
351			dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
352			bus->gtscap = bus->remap_addr + offset;
353			break;
354
355		case AZX_PP_CAP_ID:
356			/* PP capability found, the Audio DSP is present */
357			dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
358			bus->ppcap = bus->remap_addr + offset;
359			break;
360
361		case AZX_SPB_CAP_ID:
362			/* SPIB capability found, handler function */
363			dev_dbg(bus->dev, "Found SPB capability\n");
364			bus->spbcap = bus->remap_addr + offset;
365			break;
366
367		case AZX_DRSM_CAP_ID:
368			/* DMA resume  capability found, handler function */
369			dev_dbg(bus->dev, "Found DRSM capability\n");
370			bus->drsmcap = bus->remap_addr + offset;
371			break;
372
373		default:
374			dev_err(bus->dev, "Unknown capability %d\n", cur_cap);
375			cur_cap = 0;
376			break;
377		}
378
379		counter++;
380
381		if (counter > HDAC_MAX_CAPS) {
382			dev_err(bus->dev, "We exceeded HDAC capabilities!!!\n");
383			break;
384		}
385
386		/* read the offset of next capability */
387		offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;
388
389	} while (offset);
390
391	return 0;
392}
393EXPORT_SYMBOL_GPL(snd_hdac_bus_parse_capabilities);
394
395/*
396 * Lowlevel interface
397 */
398
399/**
400 * snd_hdac_bus_enter_link_reset - enter link reset
401 * @bus: HD-audio core bus
402 *
403 * Enter to the link reset state.
404 */
405void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus)
406{
407	unsigned long timeout;
408
409	/* reset controller */
410	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_RESET, 0);
411
412	timeout = jiffies + msecs_to_jiffies(100);
413	while ((snd_hdac_chip_readb(bus, GCTL) & AZX_GCTL_RESET) &&
414	       time_before(jiffies, timeout))
415		usleep_range(500, 1000);
416}
417EXPORT_SYMBOL_GPL(snd_hdac_bus_enter_link_reset);
418
419/**
420 * snd_hdac_bus_exit_link_reset - exit link reset
421 * @bus: HD-audio core bus
422 *
423 * Exit from the link reset state.
424 */
425void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus)
426{
427	unsigned long timeout;
428
429	snd_hdac_chip_updateb(bus, GCTL, AZX_GCTL_RESET, AZX_GCTL_RESET);
430
431	timeout = jiffies + msecs_to_jiffies(100);
432	while (!snd_hdac_chip_readb(bus, GCTL) && time_before(jiffies, timeout))
433		usleep_range(500, 1000);
434}
435EXPORT_SYMBOL_GPL(snd_hdac_bus_exit_link_reset);
436
437/* reset codec link */
438int snd_hdac_bus_reset_link(struct hdac_bus *bus, bool full_reset)
439{
440	if (!full_reset)
441		goto skip_reset;
442
443	/* clear STATESTS if not in reset */
444	if (snd_hdac_chip_readb(bus, GCTL) & AZX_GCTL_RESET)
445		snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
446
447	/* reset controller */
448	snd_hdac_bus_enter_link_reset(bus);
449
450	/* delay for >= 100us for codec PLL to settle per spec
451	 * Rev 0.9 section 5.5.1
452	 */
453	usleep_range(500, 1000);
454
455	/* Bring controller out of reset */
456	snd_hdac_bus_exit_link_reset(bus);
457
458	/* Brent Chartrand said to wait >= 540us for codecs to initialize */
459	usleep_range(1000, 1200);
460
461 skip_reset:
462	/* check to see if controller is ready */
463	if (!snd_hdac_chip_readb(bus, GCTL)) {
464		dev_dbg(bus->dev, "controller not ready!\n");
465		return -EBUSY;
466	}
467
468	/* detect codecs */
469	if (!bus->codec_mask) {
470		bus->codec_mask = snd_hdac_chip_readw(bus, STATESTS);
471		dev_dbg(bus->dev, "codec_mask = 0x%lx\n", bus->codec_mask);
472	}
473
474	return 0;
475}
476EXPORT_SYMBOL_GPL(snd_hdac_bus_reset_link);
477
478/* enable interrupts */
479static void azx_int_enable(struct hdac_bus *bus)
480{
481	/* enable controller CIE and GIE */
482	snd_hdac_chip_updatel(bus, INTCTL,
483			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN,
484			      AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN);
485}
486
487/* disable interrupts */
488static void azx_int_disable(struct hdac_bus *bus)
489{
490	struct hdac_stream *azx_dev;
491
492	/* disable interrupts in stream descriptor */
493	list_for_each_entry(azx_dev, &bus->stream_list, list)
494		snd_hdac_stream_updateb(azx_dev, SD_CTL, SD_INT_MASK, 0);
495
496	/* disable SIE for all streams */
497	snd_hdac_chip_writeb(bus, INTCTL, 0);
498
499	/* disable controller CIE and GIE */
500	snd_hdac_chip_updatel(bus, INTCTL, AZX_INT_CTRL_EN | AZX_INT_GLOBAL_EN, 0);
501}
502
503/* clear interrupts */
504static void azx_int_clear(struct hdac_bus *bus)
505{
506	struct hdac_stream *azx_dev;
507	struct azx *chip = bus_to_azx(bus);
508
509	/* clear stream status */
510	list_for_each_entry(azx_dev, &bus->stream_list, list) {
511		if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND)
512			snd_hdac_stream_updateb(azx_dev, SD_STS, 0, 0);
513		else
514			snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
515	}
516
517	/* clear STATESTS */
518	snd_hdac_chip_writew(bus, STATESTS, STATESTS_INT_MASK);
519
520	/* clear rirb status */
521	if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND)
522		snd_hdac_chip_updateb(bus, RIRBSTS, ~RIRB_INT_MASK, 0);
523	else
524		snd_hdac_chip_writeb(bus, RIRBSTS, RIRB_INT_MASK);
525
526	/* clear int status */
527	snd_hdac_chip_writel(bus, INTSTS, AZX_INT_CTRL_EN | AZX_INT_ALL_STREAM);
528}
529
530/**
531 * snd_hdac_bus_init_chip - reset and start the controller registers
532 * @bus: HD-audio core bus
533 * @full_reset: Do full reset
534 */
535bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset)
536{
537	if (bus->chip_init)
538		return false;
539
540	/* reset controller */
541	snd_hdac_bus_reset_link(bus, full_reset);
542
543	/* clear interrupts */
544	azx_int_clear(bus);
545
546	/* initialize the codec command I/O */
547	snd_hdac_bus_init_cmd_io(bus);
548
549	/* enable interrupts after CORB/RIRB buffers are initialized above */
550	azx_int_enable(bus);
551
552	/* program the position buffer */
553	if (bus->use_posbuf && bus->posbuf.addr) {
554		snd_hdac_chip_writel(bus, DPLBASE, (u32)bus->posbuf.addr);
555		snd_hdac_chip_writel(bus, DPUBASE, upper_32_bits(bus->posbuf.addr));
556	}
557
558	bus->chip_init = true;
559
560	return true;
561}
562EXPORT_SYMBOL_GPL(snd_hdac_bus_init_chip);
563
564/**
565 * snd_hdac_bus_stop_chip - disable the whole IRQ and I/Os
566 * @bus: HD-audio core bus
567 */
568void snd_hdac_bus_stop_chip(struct hdac_bus *bus)
569{
570	if (!bus->chip_init)
571		return;
572
573	/* disable interrupts */
574	azx_int_disable(bus);
575	azx_int_clear(bus);
576
577	/* disable CORB/RIRB */
578	snd_hdac_bus_stop_cmd_io(bus);
579
580	/* disable position buffer */
581	if (bus->posbuf.addr) {
582		snd_hdac_chip_writel(bus, DPLBASE, 0);
583		snd_hdac_chip_writel(bus, DPUBASE, 0);
584	}
585
586	bus->chip_init = false;
587}
588EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_chip);
589
590/**
591 * snd_hdac_bus_handle_stream_irq - interrupt handler for streams
592 * @bus: HD-audio core bus
593 * @status: INTSTS register value
594 * @ack: callback to be called for woken streams
595 *
596 * Returns the bits of handled streams, or zero if no stream is handled.
597 */
598int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
599				    void (*ack)(struct hdac_bus *,
600						struct hdac_stream *))
601{
602	struct hdac_stream *azx_dev;
603	u8 sd_status;
604	int handled = 0;
605	struct azx *chip = bus_to_azx(bus);
606
607	list_for_each_entry(azx_dev, &bus->stream_list, list) {
608		if (status & azx_dev->sd_int_sta_mask) {
609			sd_status = snd_hdac_stream_readb(azx_dev, SD_STS);
610			if (chip->driver_caps & AZX_DCAPS_LS2X_WORKAROUND) {
611				snd_hdac_stream_writeb(azx_dev, SD_STS, sd_status);
612				snd_hdac_stream_readb(azx_dev, SD_STS);
613			}
614			else
615				snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
616			handled |= 1 << azx_dev->index;
617			if (!azx_dev->substream || !azx_dev->running ||
618			    !(sd_status & SD_INT_COMPLETE))
619				continue;
620			if (ack)
621				ack(bus, azx_dev);
622		}
623	}
624	return handled;
625}
626EXPORT_SYMBOL_GPL(snd_hdac_bus_handle_stream_irq);
627
628/**
629 * snd_hdac_bus_alloc_stream_pages - allocate BDL and other buffers
630 * @bus: HD-audio core bus
631 *
632 * Call this after assigning the all streams.
633 * Returns zero for success, or a negative error code.
634 */
635int snd_hdac_bus_alloc_stream_pages(struct hdac_bus *bus)
636{
637	struct hdac_stream *s;
638	int num_streams = 0;
639	int dma_type = bus->dma_type ? bus->dma_type : SNDRV_DMA_TYPE_DEV;
640	int err;
641
642	list_for_each_entry(s, &bus->stream_list, list) {
643		/* allocate memory for the BDL for each stream */
644		err = snd_dma_alloc_pages(dma_type, bus->dev,
645					  BDL_SIZE, &s->bdl);
646		num_streams++;
647		if (err < 0)
648			return -ENOMEM;
649	}
650
651	if (WARN_ON(!num_streams))
652		return -EINVAL;
653	/* allocate memory for the position buffer */
654	err = snd_dma_alloc_pages(dma_type, bus->dev,
655				  num_streams * 8, &bus->posbuf);
656	if (err < 0)
657		return -ENOMEM;
658	list_for_each_entry(s, &bus->stream_list, list)
659		s->posbuf = (__le32 *)(bus->posbuf.area + s->index * 8);
660
661	/* single page (at least 4096 bytes) must suffice for both ringbuffes */
662	return snd_dma_alloc_pages(dma_type, bus->dev, PAGE_SIZE, &bus->rb);
663}
664EXPORT_SYMBOL_GPL(snd_hdac_bus_alloc_stream_pages);
665
666/**
667 * snd_hdac_bus_free_stream_pages - release BDL and other buffers
668 * @bus: HD-audio core bus
669 */
670void snd_hdac_bus_free_stream_pages(struct hdac_bus *bus)
671{
672	struct hdac_stream *s;
673
674	list_for_each_entry(s, &bus->stream_list, list) {
675		if (s->bdl.area)
676			snd_dma_free_pages(&s->bdl);
677	}
678
679	if (bus->rb.area)
680		snd_dma_free_pages(&bus->rb);
681	if (bus->posbuf.area)
682		snd_dma_free_pages(&bus->posbuf);
683}
684EXPORT_SYMBOL_GPL(snd_hdac_bus_free_stream_pages);
685