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1// SPDX-License-Identifier: GPL-2.0 OR MIT2 3/*4 * Xen para-virtual sound device5 *6 * Copyright (C) 2016-2018 EPAM Systems Inc.7 *8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>9 */10 11#include <linux/platform_device.h>12 13#include <sound/core.h>14#include <sound/pcm.h>15#include <sound/pcm_params.h>16 17#include <xen/xenbus.h>18#include <xen/xen-front-pgdir-shbuf.h>19 20#include "xen_snd_front.h"21#include "xen_snd_front_alsa.h"22#include "xen_snd_front_cfg.h"23#include "xen_snd_front_evtchnl.h"24 25struct xen_snd_front_pcm_stream_info {26	struct xen_snd_front_info *front_info;27	struct xen_snd_front_evtchnl_pair *evt_pair;28 29	/* This is the shared buffer with its backing storage. */30	struct xen_front_pgdir_shbuf shbuf;31	u8 *buffer;32	size_t buffer_sz;33	int num_pages;34	struct page **pages;35 36	int index;37 38	bool is_open;39	struct snd_pcm_hardware pcm_hw;40 41	/* Number of processed frames as reported by the backend. */42	snd_pcm_uframes_t be_cur_frame;43	/* Current HW pointer to be reported via .period callback. */44	atomic_t hw_ptr;45	/* Modulo of the number of processed frames - for period detection. */46	u32 out_frames;47};48 49struct xen_snd_front_pcm_instance_info {50	struct xen_snd_front_card_info *card_info;51	struct snd_pcm *pcm;52	struct snd_pcm_hardware pcm_hw;53	int num_pcm_streams_pb;54	struct xen_snd_front_pcm_stream_info *streams_pb;55	int num_pcm_streams_cap;56	struct xen_snd_front_pcm_stream_info *streams_cap;57};58 59struct xen_snd_front_card_info {60	struct xen_snd_front_info *front_info;61	struct snd_card *card;62	struct snd_pcm_hardware pcm_hw;63	int num_pcm_instances;64	struct xen_snd_front_pcm_instance_info *pcm_instances;65};66 67struct alsa_sndif_sample_format {68	u8 sndif;69	snd_pcm_format_t alsa;70};71 72static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {73	{74		.sndif = XENSND_PCM_FORMAT_U8,75		.alsa = SNDRV_PCM_FORMAT_U876	},77	{78		.sndif = XENSND_PCM_FORMAT_S8,79		.alsa = SNDRV_PCM_FORMAT_S880	},81	{82		.sndif = XENSND_PCM_FORMAT_U16_LE,83		.alsa = SNDRV_PCM_FORMAT_U16_LE84	},85	{86		.sndif = XENSND_PCM_FORMAT_U16_BE,87		.alsa = SNDRV_PCM_FORMAT_U16_BE88	},89	{90		.sndif = XENSND_PCM_FORMAT_S16_LE,91		.alsa = SNDRV_PCM_FORMAT_S16_LE92	},93	{94		.sndif = XENSND_PCM_FORMAT_S16_BE,95		.alsa = SNDRV_PCM_FORMAT_S16_BE96	},97	{98		.sndif = XENSND_PCM_FORMAT_U24_LE,99		.alsa = SNDRV_PCM_FORMAT_U24_LE100	},101	{102		.sndif = XENSND_PCM_FORMAT_U24_BE,103		.alsa = SNDRV_PCM_FORMAT_U24_BE104	},105	{106		.sndif = XENSND_PCM_FORMAT_S24_LE,107		.alsa = SNDRV_PCM_FORMAT_S24_LE108	},109	{110		.sndif = XENSND_PCM_FORMAT_S24_BE,111		.alsa = SNDRV_PCM_FORMAT_S24_BE112	},113	{114		.sndif = XENSND_PCM_FORMAT_U32_LE,115		.alsa = SNDRV_PCM_FORMAT_U32_LE116	},117	{118		.sndif = XENSND_PCM_FORMAT_U32_BE,119		.alsa = SNDRV_PCM_FORMAT_U32_BE120	},121	{122		.sndif = XENSND_PCM_FORMAT_S32_LE,123		.alsa = SNDRV_PCM_FORMAT_S32_LE124	},125	{126		.sndif = XENSND_PCM_FORMAT_S32_BE,127		.alsa = SNDRV_PCM_FORMAT_S32_BE128	},129	{130		.sndif = XENSND_PCM_FORMAT_A_LAW,131		.alsa = SNDRV_PCM_FORMAT_A_LAW132	},133	{134		.sndif = XENSND_PCM_FORMAT_MU_LAW,135		.alsa = SNDRV_PCM_FORMAT_MU_LAW136	},137	{138		.sndif = XENSND_PCM_FORMAT_F32_LE,139		.alsa = SNDRV_PCM_FORMAT_FLOAT_LE140	},141	{142		.sndif = XENSND_PCM_FORMAT_F32_BE,143		.alsa = SNDRV_PCM_FORMAT_FLOAT_BE144	},145	{146		.sndif = XENSND_PCM_FORMAT_F64_LE,147		.alsa = SNDRV_PCM_FORMAT_FLOAT64_LE148	},149	{150		.sndif = XENSND_PCM_FORMAT_F64_BE,151		.alsa = SNDRV_PCM_FORMAT_FLOAT64_BE152	},153	{154		.sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,155		.alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE156	},157	{158		.sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,159		.alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE160	},161	{162		.sndif = XENSND_PCM_FORMAT_IMA_ADPCM,163		.alsa = SNDRV_PCM_FORMAT_IMA_ADPCM164	},165	{166		.sndif = XENSND_PCM_FORMAT_MPEG,167		.alsa = SNDRV_PCM_FORMAT_MPEG168	},169	{170		.sndif = XENSND_PCM_FORMAT_GSM,171		.alsa = SNDRV_PCM_FORMAT_GSM172	},173};174 175static int to_sndif_format(snd_pcm_format_t format)176{177	int i;178 179	for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)180		if (ALSA_SNDIF_FORMATS[i].alsa == format)181			return ALSA_SNDIF_FORMATS[i].sndif;182 183	return -EINVAL;184}185 186static u64 to_sndif_formats_mask(u64 alsa_formats)187{188	u64 mask;189	int i;190 191	mask = 0;192	for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)193		if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats)194			mask |= BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif);195 196	return mask;197}198 199static u64 to_alsa_formats_mask(u64 sndif_formats)200{201	u64 mask;202	int i;203 204	mask = 0;205	for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)206		if (BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif) & sndif_formats)207			mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);208 209	return mask;210}211 212static void stream_clear(struct xen_snd_front_pcm_stream_info *stream)213{214	stream->is_open = false;215	stream->be_cur_frame = 0;216	stream->out_frames = 0;217	atomic_set(&stream->hw_ptr, 0);218	xen_snd_front_evtchnl_pair_clear(stream->evt_pair);219	memset(&stream->shbuf, 0, sizeof(stream->shbuf));220	stream->buffer = NULL;221	stream->buffer_sz = 0;222	stream->pages = NULL;223	stream->num_pages = 0;224}225 226static void stream_free(struct xen_snd_front_pcm_stream_info *stream)227{228	xen_front_pgdir_shbuf_unmap(&stream->shbuf);229	xen_front_pgdir_shbuf_free(&stream->shbuf);230	if (stream->buffer)231		free_pages_exact(stream->buffer, stream->buffer_sz);232	kfree(stream->pages);233	stream_clear(stream);234}235 236static struct xen_snd_front_pcm_stream_info *237stream_get(struct snd_pcm_substream *substream)238{239	struct xen_snd_front_pcm_instance_info *pcm_instance =240			snd_pcm_substream_chip(substream);241	struct xen_snd_front_pcm_stream_info *stream;242 243	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)244		stream = &pcm_instance->streams_pb[substream->number];245	else246		stream = &pcm_instance->streams_cap[substream->number];247 248	return stream;249}250 251static int alsa_hw_rule(struct snd_pcm_hw_params *params,252			struct snd_pcm_hw_rule *rule)253{254	struct xen_snd_front_pcm_stream_info *stream = rule->private;255	struct device *dev = &stream->front_info->xb_dev->dev;256	struct snd_mask *formats =257			hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);258	struct snd_interval *rates =259			hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);260	struct snd_interval *channels =261			hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);262	struct snd_interval *period =263			hw_param_interval(params,264					  SNDRV_PCM_HW_PARAM_PERIOD_SIZE);265	struct snd_interval *buffer =266			hw_param_interval(params,267					  SNDRV_PCM_HW_PARAM_BUFFER_SIZE);268	struct xensnd_query_hw_param req;269	struct xensnd_query_hw_param resp;270	struct snd_interval interval;271	struct snd_mask mask;272	u64 sndif_formats;273	int changed, ret;274 275	/* Collect all the values we need for the query. */276 277	req.formats = to_sndif_formats_mask((u64)formats->bits[0] |278					    (u64)(formats->bits[1]) << 32);279 280	req.rates.min = rates->min;281	req.rates.max = rates->max;282 283	req.channels.min = channels->min;284	req.channels.max = channels->max;285 286	req.buffer.min = buffer->min;287	req.buffer.max = buffer->max;288 289	req.period.min = period->min;290	req.period.max = period->max;291 292	ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,293						  &req, &resp);294	if (ret < 0) {295		/* Check if this is due to backend communication error. */296		if (ret == -EIO || ret == -ETIMEDOUT)297			dev_err(dev, "Failed to query ALSA HW parameters\n");298		return ret;299	}300 301	/* Refine HW parameters after the query. */302	changed  = 0;303 304	sndif_formats = to_alsa_formats_mask(resp.formats);305	snd_mask_none(&mask);306	mask.bits[0] = (u32)sndif_formats;307	mask.bits[1] = (u32)(sndif_formats >> 32);308	ret = snd_mask_refine(formats, &mask);309	if (ret < 0)310		return ret;311	changed |= ret;312 313	interval.openmin = 0;314	interval.openmax = 0;315	interval.integer = 1;316 317	interval.min = resp.rates.min;318	interval.max = resp.rates.max;319	ret = snd_interval_refine(rates, &interval);320	if (ret < 0)321		return ret;322	changed |= ret;323 324	interval.min = resp.channels.min;325	interval.max = resp.channels.max;326	ret = snd_interval_refine(channels, &interval);327	if (ret < 0)328		return ret;329	changed |= ret;330 331	interval.min = resp.buffer.min;332	interval.max = resp.buffer.max;333	ret = snd_interval_refine(buffer, &interval);334	if (ret < 0)335		return ret;336	changed |= ret;337 338	interval.min = resp.period.min;339	interval.max = resp.period.max;340	ret = snd_interval_refine(period, &interval);341	if (ret < 0)342		return ret;343	changed |= ret;344 345	return changed;346}347 348static int alsa_open(struct snd_pcm_substream *substream)349{350	struct xen_snd_front_pcm_instance_info *pcm_instance =351			snd_pcm_substream_chip(substream);352	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);353	struct snd_pcm_runtime *runtime = substream->runtime;354	struct xen_snd_front_info *front_info =355			pcm_instance->card_info->front_info;356	struct device *dev = &front_info->xb_dev->dev;357	int ret;358 359	/*360	 * Return our HW properties: override defaults with those configured361	 * via XenStore.362	 */363	runtime->hw = stream->pcm_hw;364	runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |365			      SNDRV_PCM_INFO_MMAP_VALID |366			      SNDRV_PCM_INFO_DOUBLE |367			      SNDRV_PCM_INFO_BATCH |368			      SNDRV_PCM_INFO_NONINTERLEAVED |369			      SNDRV_PCM_INFO_RESUME |370			      SNDRV_PCM_INFO_PAUSE);371	runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;372 373	stream->evt_pair = &front_info->evt_pairs[stream->index];374 375	stream->front_info = front_info;376 377	stream->evt_pair->evt.u.evt.substream = substream;378 379	stream_clear(stream);380 381	xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);382 383	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,384				  alsa_hw_rule, stream,385				  SNDRV_PCM_HW_PARAM_FORMAT, -1);386	if (ret) {387		dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");388		return ret;389	}390 391	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,392				  alsa_hw_rule, stream,393				  SNDRV_PCM_HW_PARAM_RATE, -1);394	if (ret) {395		dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");396		return ret;397	}398 399	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,400				  alsa_hw_rule, stream,401				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);402	if (ret) {403		dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");404		return ret;405	}406 407	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,408				  alsa_hw_rule, stream,409				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);410	if (ret) {411		dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");412		return ret;413	}414 415	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,416				  alsa_hw_rule, stream,417				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);418	if (ret) {419		dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");420		return ret;421	}422 423	return 0;424}425 426static int alsa_close(struct snd_pcm_substream *substream)427{428	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);429 430	xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);431	return 0;432}433 434static int shbuf_setup_backstore(struct xen_snd_front_pcm_stream_info *stream,435				 size_t buffer_sz)436{437	int i;438 439	stream->buffer = alloc_pages_exact(buffer_sz, GFP_KERNEL);440	if (!stream->buffer)441		return -ENOMEM;442 443	stream->buffer_sz = buffer_sz;444	stream->num_pages = DIV_ROUND_UP(stream->buffer_sz, PAGE_SIZE);445	stream->pages = kcalloc(stream->num_pages, sizeof(struct page *),446				GFP_KERNEL);447	if (!stream->pages)448		return -ENOMEM;449 450	for (i = 0; i < stream->num_pages; i++)451		stream->pages[i] = virt_to_page(stream->buffer + i * PAGE_SIZE);452 453	return 0;454}455 456static int alsa_hw_params(struct snd_pcm_substream *substream,457			  struct snd_pcm_hw_params *params)458{459	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);460	struct xen_snd_front_info *front_info = stream->front_info;461	struct xen_front_pgdir_shbuf_cfg buf_cfg;462	int ret;463 464	/*465	 * This callback may be called multiple times,466	 * so free the previously allocated shared buffer if any.467	 */468	stream_free(stream);469	ret = shbuf_setup_backstore(stream, params_buffer_bytes(params));470	if (ret < 0)471		goto fail;472 473	memset(&buf_cfg, 0, sizeof(buf_cfg));474	buf_cfg.xb_dev = front_info->xb_dev;475	buf_cfg.pgdir = &stream->shbuf;476	buf_cfg.num_pages = stream->num_pages;477	buf_cfg.pages = stream->pages;478 479	ret = xen_front_pgdir_shbuf_alloc(&buf_cfg);480	if (ret < 0)481		goto fail;482 483	ret = xen_front_pgdir_shbuf_map(&stream->shbuf);484	if (ret < 0)485		goto fail;486 487	return 0;488 489fail:490	stream_free(stream);491	dev_err(&front_info->xb_dev->dev,492		"Failed to allocate buffers for stream with index %d\n",493		stream->index);494	return ret;495}496 497static int alsa_hw_free(struct snd_pcm_substream *substream)498{499	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);500	int ret;501 502	ret = xen_snd_front_stream_close(&stream->evt_pair->req);503	stream_free(stream);504	return ret;505}506 507static int alsa_prepare(struct snd_pcm_substream *substream)508{509	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);510 511	if (!stream->is_open) {512		struct snd_pcm_runtime *runtime = substream->runtime;513		u8 sndif_format;514		int ret;515 516		ret = to_sndif_format(runtime->format);517		if (ret < 0) {518			dev_err(&stream->front_info->xb_dev->dev,519				"Unsupported sample format: %d\n",520				runtime->format);521			return ret;522		}523		sndif_format = ret;524 525		ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,526						   &stream->shbuf,527						   sndif_format,528						   runtime->channels,529						   runtime->rate,530						   snd_pcm_lib_buffer_bytes(substream),531						   snd_pcm_lib_period_bytes(substream));532		if (ret < 0)533			return ret;534 535		stream->is_open = true;536	}537 538	return 0;539}540 541static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)542{543	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);544	int type;545 546	switch (cmd) {547	case SNDRV_PCM_TRIGGER_START:548		type = XENSND_OP_TRIGGER_START;549		break;550 551	case SNDRV_PCM_TRIGGER_RESUME:552		type = XENSND_OP_TRIGGER_RESUME;553		break;554 555	case SNDRV_PCM_TRIGGER_STOP:556		type = XENSND_OP_TRIGGER_STOP;557		break;558 559	case SNDRV_PCM_TRIGGER_SUSPEND:560		type = XENSND_OP_TRIGGER_PAUSE;561		break;562 563	default:564		return -EINVAL;565	}566 567	return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);568}569 570void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,571				       u64 pos_bytes)572{573	struct snd_pcm_substream *substream = evtchnl->u.evt.substream;574	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);575	snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;576 577	cur_frame = bytes_to_frames(substream->runtime, pos_bytes);578 579	delta = cur_frame - stream->be_cur_frame;580	stream->be_cur_frame = cur_frame;581 582	new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);583	new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;584	atomic_set(&stream->hw_ptr, (int)new_hw_ptr);585 586	stream->out_frames += delta;587	if (stream->out_frames > substream->runtime->period_size) {588		stream->out_frames %= substream->runtime->period_size;589		snd_pcm_period_elapsed(substream);590	}591}592 593static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)594{595	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);596 597	return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);598}599 600static int alsa_pb_copy(struct snd_pcm_substream *substream,601			int channel, unsigned long pos, struct iov_iter *src,602			unsigned long count)603{604	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);605 606	if (unlikely(pos + count > stream->buffer_sz))607		return -EINVAL;608 609	if (copy_from_iter(stream->buffer + pos, count, src) != count)610		return -EFAULT;611 612	return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);613}614 615static int alsa_cap_copy(struct snd_pcm_substream *substream,616			 int channel, unsigned long pos, struct iov_iter *dst,617			 unsigned long count)618{619	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);620	int ret;621 622	if (unlikely(pos + count > stream->buffer_sz))623		return -EINVAL;624 625	ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);626	if (ret < 0)627		return ret;628 629	if (copy_to_iter(stream->buffer + pos, count, dst) != count)630		return -EFAULT;631	return 0;632}633 634static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,635				int channel, unsigned long pos,636				unsigned long count)637{638	struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);639 640	if (unlikely(pos + count > stream->buffer_sz))641		return -EINVAL;642 643	memset(stream->buffer + pos, 0, count);644 645	return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);646}647 648/*649 * FIXME: The mmaped data transfer is asynchronous and there is no650 * ack signal from user-space when it is done. This is the651 * reason it is not implemented in the PV driver as we do need652 * to know when the buffer can be transferred to the backend.653 */654 655static const struct snd_pcm_ops snd_drv_alsa_playback_ops = {656	.open		= alsa_open,657	.close		= alsa_close,658	.hw_params	= alsa_hw_params,659	.hw_free	= alsa_hw_free,660	.prepare	= alsa_prepare,661	.trigger	= alsa_trigger,662	.pointer	= alsa_pointer,663	.copy		= alsa_pb_copy,664	.fill_silence	= alsa_pb_fill_silence,665};666 667static const struct snd_pcm_ops snd_drv_alsa_capture_ops = {668	.open		= alsa_open,669	.close		= alsa_close,670	.hw_params	= alsa_hw_params,671	.hw_free	= alsa_hw_free,672	.prepare	= alsa_prepare,673	.trigger	= alsa_trigger,674	.pointer	= alsa_pointer,675	.copy		= alsa_cap_copy,676};677 678static int new_pcm_instance(struct xen_snd_front_card_info *card_info,679			    struct xen_front_cfg_pcm_instance *instance_cfg,680			    struct xen_snd_front_pcm_instance_info *pcm_instance_info)681{682	struct snd_pcm *pcm;683	int ret, i;684 685	dev_dbg(&card_info->front_info->xb_dev->dev,686		"New PCM device \"%s\" with id %d playback %d capture %d",687		instance_cfg->name,688		instance_cfg->device_id,689		instance_cfg->num_streams_pb,690		instance_cfg->num_streams_cap);691 692	pcm_instance_info->card_info = card_info;693 694	pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;695 696	if (instance_cfg->num_streams_pb) {697		pcm_instance_info->streams_pb =698				devm_kcalloc(&card_info->card->card_dev,699					     instance_cfg->num_streams_pb,700					     sizeof(struct xen_snd_front_pcm_stream_info),701					     GFP_KERNEL);702		if (!pcm_instance_info->streams_pb)703			return -ENOMEM;704	}705 706	if (instance_cfg->num_streams_cap) {707		pcm_instance_info->streams_cap =708				devm_kcalloc(&card_info->card->card_dev,709					     instance_cfg->num_streams_cap,710					     sizeof(struct xen_snd_front_pcm_stream_info),711					     GFP_KERNEL);712		if (!pcm_instance_info->streams_cap)713			return -ENOMEM;714	}715 716	pcm_instance_info->num_pcm_streams_pb =717			instance_cfg->num_streams_pb;718	pcm_instance_info->num_pcm_streams_cap =719			instance_cfg->num_streams_cap;720 721	for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {722		pcm_instance_info->streams_pb[i].pcm_hw =723			instance_cfg->streams_pb[i].pcm_hw;724		pcm_instance_info->streams_pb[i].index =725			instance_cfg->streams_pb[i].index;726	}727 728	for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {729		pcm_instance_info->streams_cap[i].pcm_hw =730			instance_cfg->streams_cap[i].pcm_hw;731		pcm_instance_info->streams_cap[i].index =732			instance_cfg->streams_cap[i].index;733	}734 735	ret = snd_pcm_new(card_info->card, instance_cfg->name,736			  instance_cfg->device_id,737			  instance_cfg->num_streams_pb,738			  instance_cfg->num_streams_cap,739			  &pcm);740	if (ret < 0)741		return ret;742 743	pcm->private_data = pcm_instance_info;744	pcm->info_flags = 0;745	/* we want to handle all PCM operations in non-atomic context */746	pcm->nonatomic = true;747	strscpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));748 749	if (instance_cfg->num_streams_pb)750		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,751				&snd_drv_alsa_playback_ops);752 753	if (instance_cfg->num_streams_cap)754		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,755				&snd_drv_alsa_capture_ops);756 757	pcm_instance_info->pcm = pcm;758	return 0;759}760 761int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)762{763	struct device *dev = &front_info->xb_dev->dev;764	struct xen_front_cfg_card *cfg = &front_info->cfg;765	struct xen_snd_front_card_info *card_info;766	struct snd_card *card;767	int ret, i;768 769	dev_dbg(dev, "Creating virtual sound card\n");770 771	ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,772			   sizeof(struct xen_snd_front_card_info), &card);773	if (ret < 0)774		return ret;775 776	card_info = card->private_data;777	card_info->front_info = front_info;778	front_info->card_info = card_info;779	card_info->card = card;780	card_info->pcm_instances =781			devm_kcalloc(dev, cfg->num_pcm_instances,782				     sizeof(struct xen_snd_front_pcm_instance_info),783				     GFP_KERNEL);784	if (!card_info->pcm_instances) {785		ret = -ENOMEM;786		goto fail;787	}788 789	card_info->num_pcm_instances = cfg->num_pcm_instances;790	card_info->pcm_hw = cfg->pcm_hw;791 792	for (i = 0; i < cfg->num_pcm_instances; i++) {793		ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],794				       &card_info->pcm_instances[i]);795		if (ret < 0)796			goto fail;797	}798 799	strscpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));800	strscpy(card->shortname, cfg->name_short, sizeof(card->shortname));801	strscpy(card->longname, cfg->name_long, sizeof(card->longname));802 803	ret = snd_card_register(card);804	if (ret < 0)805		goto fail;806 807	return 0;808 809fail:810	snd_card_free(card);811	return ret;812}813 814void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)815{816	struct xen_snd_front_card_info *card_info;817	struct snd_card *card;818 819	card_info = front_info->card_info;820	if (!card_info)821		return;822 823	card = card_info->card;824	if (!card)825		return;826 827	dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",828		card->number);829	snd_card_free(card);830 831	/* Card_info will be freed when destroying front_info->xb_dev->dev. */832	card_info->card = NULL;833}834