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1/* SPDX-License-Identifier: MIT */2/******************************************************************************3 * sndif.h4 *5 * Unified sound-device I/O interface for Xen guest OSes.6 *7 * Copyright (C) 2013-2015 GlobalLogic Inc.8 * Copyright (C) 2016-2017 EPAM Systems Inc.9 *10 * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>11 * Oleksandr Grytsov <oleksandr_grytsov@epam.com>12 * Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>13 * Iurii Konovalenko <iurii.konovalenko@globallogic.com>14 */15 16#ifndef __XEN_PUBLIC_IO_SNDIF_H__17#define __XEN_PUBLIC_IO_SNDIF_H__18 19#include "ring.h"20#include "../grant_table.h"21 22/*23 ******************************************************************************24 * Protocol version25 ******************************************************************************26 */27#define XENSND_PROTOCOL_VERSION 228 29/*30 ******************************************************************************31 * Feature and Parameter Negotiation32 ******************************************************************************33 *34 * Front->back notifications: when enqueuing a new request, sending a35 * notification can be made conditional on xensnd_req (i.e., the generic36 * hold-off mechanism provided by the ring macros). Backends must set37 * xensnd_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()).38 *39 * Back->front notifications: when enqueuing a new response, sending a40 * notification can be made conditional on xensnd_resp (i.e., the generic41 * hold-off mechanism provided by the ring macros). Frontends must set42 * xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).43 *44 * The two halves of a para-virtual sound card driver utilize nodes within45 * XenStore to communicate capabilities and to negotiate operating parameters.46 * This section enumerates these nodes which reside in the respective front and47 * backend portions of XenStore, following the XenBus convention.48 *49 * All data in XenStore is stored as strings. Nodes specifying numeric50 * values are encoded in decimal. Integer value ranges listed below are51 * expressed as fixed sized integer types capable of storing the conversion52 * of a properly formated node string, without loss of information.53 *54 ******************************************************************************55 * Example configuration56 ******************************************************************************57 *58 * Note: depending on the use-case backend can expose more sound cards and59 * PCM devices/streams than the underlying HW physically has by employing60 * SW mixers, configuring virtual sound streams, channels etc.61 *62 * This is an example of backend and frontend configuration:63 *64 *--------------------------------- Backend -----------------------------------65 *66 * /local/domain/0/backend/vsnd/1/0/frontend-id = "1"67 * /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0"68 * /local/domain/0/backend/vsnd/1/0/state = "4"69 * /local/domain/0/backend/vsnd/1/0/versions = "1,2"70 *71 *--------------------------------- Frontend ----------------------------------72 *73 * /local/domain/1/device/vsnd/0/backend-id = "0"74 * /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0"75 * /local/domain/1/device/vsnd/0/state = "4"76 * /local/domain/1/device/vsnd/0/version = "1"77 *78 *----------------------------- Card configuration ----------------------------79 *80 * /local/domain/1/device/vsnd/0/short-name = "Card short name"81 * /local/domain/1/device/vsnd/0/long-name = "Card long name"82 * /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000"83 * /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be"84 * /local/domain/1/device/vsnd/0/buffer-size = "262144"85 *86 *------------------------------- PCM device 0 --------------------------------87 *88 * /local/domain/1/device/vsnd/0/0/name = "General analog"89 * /local/domain/1/device/vsnd/0/0/channels-max = "5"90 *91 *----------------------------- Stream 0, playback ----------------------------92 *93 * /local/domain/1/device/vsnd/0/0/0/type = "p"94 * /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8"95 * /local/domain/1/device/vsnd/0/0/0/unique-id = "0"96 *97 * /local/domain/1/device/vsnd/0/0/0/ring-ref = "386"98 * /local/domain/1/device/vsnd/0/0/0/event-channel = "15"99 * /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386"100 * /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215"101 *102 *------------------------------ Stream 1, capture ----------------------------103 *104 * /local/domain/1/device/vsnd/0/0/1/type = "c"105 * /local/domain/1/device/vsnd/0/0/1/channels-max = "2"106 * /local/domain/1/device/vsnd/0/0/1/unique-id = "1"107 *108 * /local/domain/1/device/vsnd/0/0/1/ring-ref = "384"109 * /local/domain/1/device/vsnd/0/0/1/event-channel = "13"110 * /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384"111 * /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213"112 *113 *------------------------------- PCM device 1 --------------------------------114 *115 * /local/domain/1/device/vsnd/0/1/name = "HDMI-0"116 * /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100"117 *118 *------------------------------ Stream 0, capture ----------------------------119 *120 * /local/domain/1/device/vsnd/0/1/0/type = "c"121 * /local/domain/1/device/vsnd/0/1/0/unique-id = "2"122 *123 * /local/domain/1/device/vsnd/0/1/0/ring-ref = "387"124 * /local/domain/1/device/vsnd/0/1/0/event-channel = "151"125 * /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387"126 * /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351"127 *128 *------------------------------- PCM device 2 --------------------------------129 *130 * /local/domain/1/device/vsnd/0/2/name = "SPDIF"131 *132 *----------------------------- Stream 0, playback ----------------------------133 *134 * /local/domain/1/device/vsnd/0/2/0/type = "p"135 * /local/domain/1/device/vsnd/0/2/0/unique-id = "3"136 *137 * /local/domain/1/device/vsnd/0/2/0/ring-ref = "389"138 * /local/domain/1/device/vsnd/0/2/0/event-channel = "152"139 * /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389"140 * /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452"141 *142 ******************************************************************************143 * Backend XenBus Nodes144 ******************************************************************************145 *146 *----------------------------- Protocol version ------------------------------147 *148 * versions149 * Values: <string>150 *151 * List of XENSND_LIST_SEPARATOR separated protocol versions supported152 * by the backend. For example "1,2,3".153 *154 ******************************************************************************155 * Frontend XenBus Nodes156 ******************************************************************************157 *158 *-------------------------------- Addressing ---------------------------------159 *160 * dom-id161 * Values: <uint16_t>162 *163 * Domain identifier.164 *165 * dev-id166 * Values: <uint16_t>167 *168 * Device identifier.169 *170 * pcm-dev-idx171 * Values: <uint8_t>172 *173 * Zero based contigous index of the PCM device.174 *175 * stream-idx176 * Values: <uint8_t>177 *178 * Zero based contigous index of the stream of the PCM device.179 *180 * The following pattern is used for addressing:181 * /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/...182 *183 *----------------------------- Protocol version ------------------------------184 *185 * version186 * Values: <string>187 *188 * Protocol version, chosen among the ones supported by the backend.189 *190 *------------------------------- PCM settings --------------------------------191 *192 * Every virtualized sound frontend has a set of PCM devices and streams, each193 * could be individually configured. Part of the PCM configuration can be194 * defined at higher level of the hierarchy and be fully or partially re-used195 * by the underlying layers. These configuration values are:196 * o number of channels (min/max)197 * o supported sample rates198 * o supported sample formats.199 * E.g. one can define these values for the whole card, device or stream.200 * Every underlying layer in turn can re-define some or all of them to better201 * fit its needs. For example, card may define number of channels to be202 * in [1; 8] range, and some particular stream may be limited to [1; 2] only.203 * The rule is that the underlying layer must be a subset of the upper layer204 * range.205 *206 * channels-min207 * Values: <uint8_t>208 *209 * The minimum amount of channels that is supported, [1; channels-max].210 * Optional, if not set or omitted a value of 1 is used.211 *212 * channels-max213 * Values: <uint8_t>214 *215 * The maximum amount of channels that is supported.216 * Must be at least <channels-min>.217 *218 * sample-rates219 * Values: <list of uint32_t>220 *221 * List of supported sample rates separated by XENSND_LIST_SEPARATOR.222 * Sample rates are expressed as a list of decimal values w/o any223 * ordering requirement.224 *225 * sample-formats226 * Values: <list of XENSND_PCM_FORMAT_XXX_STR>227 *228 * List of supported sample formats separated by XENSND_LIST_SEPARATOR.229 * Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length.230 *231 * buffer-size232 * Values: <uint32_t>233 *234 * The maximum size in octets of the buffer to allocate per stream.235 *236 *----------------------- Virtual sound card settings -------------------------237 * short-name238 * Values: <char[32]>239 *240 * Short name of the virtual sound card. Optional.241 *242 * long-name243 * Values: <char[80]>244 *245 * Long name of the virtual sound card. Optional.246 *247 *----------------------------- Device settings -------------------------------248 * name249 * Values: <char[80]>250 *251 * Name of the sound device within the virtual sound card. Optional.252 *253 *----------------------------- Stream settings -------------------------------254 *255 * type256 * Values: "p", "c"257 *258 * Stream type: "p" - playback stream, "c" - capture stream259 *260 * If both capture and playback are needed then two streams need to be261 * defined under the same device.262 *263 * unique-id264 * Values: <string>265 *266 * After stream initialization it is assigned a unique ID, so every267 * stream of the frontend can be identified by the backend by this ID.268 * This can be UUID or such.269 *270 *-------------------- Stream Request Transport Parameters --------------------271 *272 * event-channel273 * Values: <uint32_t>274 *275 * The identifier of the Xen event channel used to signal activity276 * in the ring buffer.277 *278 * ring-ref279 * Values: <uint32_t>280 *281 * The Xen grant reference granting permission for the backend to map282 * a sole page in a single page sized ring buffer.283 *284 *--------------------- Stream Event Transport Parameters ---------------------285 *286 * This communication path is used to deliver asynchronous events from backend287 * to frontend, set up per stream.288 *289 * evt-event-channel290 * Values: <uint32_t>291 *292 * The identifier of the Xen event channel used to signal activity293 * in the ring buffer.294 *295 * evt-ring-ref296 * Values: <uint32_t>297 *298 * The Xen grant reference granting permission for the backend to map299 * a sole page in a single page sized ring buffer.300 *301 ******************************************************************************302 * STATE DIAGRAMS303 ******************************************************************************304 *305 * Tool stack creates front and back state nodes with initial state306 * XenbusStateInitialising.307 * Tool stack creates and sets up frontend sound configuration nodes per domain.308 *309 * Front Back310 * ================================= =====================================311 * XenbusStateInitialising XenbusStateInitialising312 * o Query backend device identification313 * data.314 * o Open and validate backend device.315 * |316 * |317 * V318 * XenbusStateInitWait319 *320 * o Query frontend configuration321 * o Allocate and initialize322 * event channels per configured323 * playback/capture stream.324 * o Publish transport parameters325 * that will be in effect during326 * this connection.327 * |328 * |329 * V330 * XenbusStateInitialised331 *332 * o Query frontend transport parameters.333 * o Connect to the event channels.334 * |335 * |336 * V337 * XenbusStateConnected338 *339 * o Create and initialize OS340 * virtual sound device instances341 * as per configuration.342 * |343 * |344 * V345 * XenbusStateConnected346 *347 * XenbusStateUnknown348 * XenbusStateClosed349 * XenbusStateClosing350 * o Remove virtual sound device351 * o Remove event channels352 * |353 * |354 * V355 * XenbusStateClosed356 *357 *------------------------------- Recovery flow -------------------------------358 *359 * In case of frontend unrecoverable errors backend handles that as360 * if frontend goes into the XenbusStateClosed state.361 *362 * In case of backend unrecoverable errors frontend tries removing363 * the virtualized device. If this is possible at the moment of error,364 * then frontend goes into the XenbusStateInitialising state and is ready for365 * new connection with backend. If the virtualized device is still in use and366 * cannot be removed, then frontend goes into the XenbusStateReconfiguring state367 * until either the virtualized device removed or backend initiates a new368 * connection. On the virtualized device removal frontend goes into the369 * XenbusStateInitialising state.370 *371 * Note on XenbusStateReconfiguring state of the frontend: if backend has372 * unrecoverable errors then frontend cannot send requests to the backend373 * and thus cannot provide functionality of the virtualized device anymore.374 * After backend is back to normal the virtualized device may still hold some375 * state: configuration in use, allocated buffers, client application state etc.376 * So, in most cases, this will require frontend to implement complex recovery377 * reconnect logic. Instead, by going into XenbusStateReconfiguring state,378 * frontend will make sure no new clients of the virtualized device are379 * accepted, allow existing client(s) to exit gracefully by signaling error380 * state etc.381 * Once all the clients are gone frontend can reinitialize the virtualized382 * device and get into XenbusStateInitialising state again signaling the383 * backend that a new connection can be made.384 *385 * There are multiple conditions possible under which frontend will go from386 * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS387 * specific. For example:388 * 1. The underlying OS framework may provide callbacks to signal that the last389 * client of the virtualized device has gone and the device can be removed390 * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue)391 * to periodically check if this is the right time to re-try removal of392 * the virtualized device.393 * 3. By any other means.394 *395 ******************************************************************************396 * PCM FORMATS397 ******************************************************************************398 *399 * XENSND_PCM_FORMAT_<format>[_<endian>]400 *401 * format: <S/U/F><bits> or <name>402 * S - signed, U - unsigned, F - float403 * bits - 8, 16, 24, 32404 * name - MU_LAW, GSM, etc.405 *406 * endian: <LE/BE>, may be absent407 * LE - Little endian, BE - Big endian408 */409#define XENSND_PCM_FORMAT_S8 0410#define XENSND_PCM_FORMAT_U8 1411#define XENSND_PCM_FORMAT_S16_LE 2412#define XENSND_PCM_FORMAT_S16_BE 3413#define XENSND_PCM_FORMAT_U16_LE 4414#define XENSND_PCM_FORMAT_U16_BE 5415#define XENSND_PCM_FORMAT_S24_LE 6416#define XENSND_PCM_FORMAT_S24_BE 7417#define XENSND_PCM_FORMAT_U24_LE 8418#define XENSND_PCM_FORMAT_U24_BE 9419#define XENSND_PCM_FORMAT_S32_LE 10420#define XENSND_PCM_FORMAT_S32_BE 11421#define XENSND_PCM_FORMAT_U32_LE 12422#define XENSND_PCM_FORMAT_U32_BE 13423#define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */424#define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */425#define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */426#define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */427#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18428#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19429#define XENSND_PCM_FORMAT_MU_LAW 20430#define XENSND_PCM_FORMAT_A_LAW 21431#define XENSND_PCM_FORMAT_IMA_ADPCM 22432#define XENSND_PCM_FORMAT_MPEG 23433#define XENSND_PCM_FORMAT_GSM 24434 435/*436 ******************************************************************************437 * REQUEST CODES438 ******************************************************************************439 */440#define XENSND_OP_OPEN 0441#define XENSND_OP_CLOSE 1442#define XENSND_OP_READ 2443#define XENSND_OP_WRITE 3444#define XENSND_OP_SET_VOLUME 4445#define XENSND_OP_GET_VOLUME 5446#define XENSND_OP_MUTE 6447#define XENSND_OP_UNMUTE 7448#define XENSND_OP_TRIGGER 8449#define XENSND_OP_HW_PARAM_QUERY 9450 451#define XENSND_OP_TRIGGER_START 0452#define XENSND_OP_TRIGGER_PAUSE 1453#define XENSND_OP_TRIGGER_STOP 2454#define XENSND_OP_TRIGGER_RESUME 3455 456/*457 ******************************************************************************458 * EVENT CODES459 ******************************************************************************460 */461#define XENSND_EVT_CUR_POS 0462 463/*464 ******************************************************************************465 * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS466 ******************************************************************************467 */468#define XENSND_DRIVER_NAME "vsnd"469 470#define XENSND_LIST_SEPARATOR ","471/* Field names */472#define XENSND_FIELD_BE_VERSIONS "versions"473#define XENSND_FIELD_FE_VERSION "version"474#define XENSND_FIELD_VCARD_SHORT_NAME "short-name"475#define XENSND_FIELD_VCARD_LONG_NAME "long-name"476#define XENSND_FIELD_RING_REF "ring-ref"477#define XENSND_FIELD_EVT_CHNL "event-channel"478#define XENSND_FIELD_EVT_RING_REF "evt-ring-ref"479#define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel"480#define XENSND_FIELD_DEVICE_NAME "name"481#define XENSND_FIELD_TYPE "type"482#define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id"483#define XENSND_FIELD_CHANNELS_MIN "channels-min"484#define XENSND_FIELD_CHANNELS_MAX "channels-max"485#define XENSND_FIELD_SAMPLE_RATES "sample-rates"486#define XENSND_FIELD_SAMPLE_FORMATS "sample-formats"487#define XENSND_FIELD_BUFFER_SIZE "buffer-size"488 489/* Stream type field values. */490#define XENSND_STREAM_TYPE_PLAYBACK "p"491#define XENSND_STREAM_TYPE_CAPTURE "c"492/* Sample rate max string length */493#define XENSND_SAMPLE_RATE_MAX_LEN 11494/* Sample format field values */495#define XENSND_SAMPLE_FORMAT_MAX_LEN 24496 497#define XENSND_PCM_FORMAT_S8_STR "s8"498#define XENSND_PCM_FORMAT_U8_STR "u8"499#define XENSND_PCM_FORMAT_S16_LE_STR "s16_le"500#define XENSND_PCM_FORMAT_S16_BE_STR "s16_be"501#define XENSND_PCM_FORMAT_U16_LE_STR "u16_le"502#define XENSND_PCM_FORMAT_U16_BE_STR "u16_be"503#define XENSND_PCM_FORMAT_S24_LE_STR "s24_le"504#define XENSND_PCM_FORMAT_S24_BE_STR "s24_be"505#define XENSND_PCM_FORMAT_U24_LE_STR "u24_le"506#define XENSND_PCM_FORMAT_U24_BE_STR "u24_be"507#define XENSND_PCM_FORMAT_S32_LE_STR "s32_le"508#define XENSND_PCM_FORMAT_S32_BE_STR "s32_be"509#define XENSND_PCM_FORMAT_U32_LE_STR "u32_le"510#define XENSND_PCM_FORMAT_U32_BE_STR "u32_be"511#define XENSND_PCM_FORMAT_F32_LE_STR "float_le"512#define XENSND_PCM_FORMAT_F32_BE_STR "float_be"513#define XENSND_PCM_FORMAT_F64_LE_STR "float64_le"514#define XENSND_PCM_FORMAT_F64_BE_STR "float64_be"515#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR "iec958_subframe_le"516#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR "iec958_subframe_be"517#define XENSND_PCM_FORMAT_MU_LAW_STR "mu_law"518#define XENSND_PCM_FORMAT_A_LAW_STR "a_law"519#define XENSND_PCM_FORMAT_IMA_ADPCM_STR "ima_adpcm"520#define XENSND_PCM_FORMAT_MPEG_STR "mpeg"521#define XENSND_PCM_FORMAT_GSM_STR "gsm"522 523 524/*525 ******************************************************************************526 * STATUS RETURN CODES527 ******************************************************************************528 *529 * Status return code is zero on success and -XEN_EXX on failure.530 *531 ******************************************************************************532 * Assumptions533 ******************************************************************************534 * o usage of grant reference 0 as invalid grant reference:535 * grant reference 0 is valid, but never exposed to a PV driver,536 * because of the fact it is already in use/reserved by the PV console.537 * o all references in this document to page sizes must be treated538 * as pages of size XEN_PAGE_SIZE unless otherwise noted.539 *540 ******************************************************************************541 * Description of the protocol between frontend and backend driver542 ******************************************************************************543 *544 * The two halves of a Para-virtual sound driver communicate with545 * each other using shared pages and event channels.546 * Shared page contains a ring with request/response packets.547 *548 * Packets, used for input/output operations, e.g. read/write, set/get volume,549 * etc., provide offset/length fields in order to allow asynchronous protocol550 * operation with buffer space sharing: part of the buffer allocated at551 * XENSND_OP_OPEN can be used for audio samples and part, for example,552 * for volume control.553 *554 * All reserved fields in the structures below must be 0.555 *556 *---------------------------------- Requests ---------------------------------557 *558 * All request packets have the same length (64 octets)559 * All request packets have common header:560 * 0 1 2 3 octet561 * +----------------+----------------+----------------+----------------+562 * | id | operation | reserved | 4563 * +----------------+----------------+----------------+----------------+564 * | reserved | 8565 * +----------------+----------------+----------------+----------------+566 * id - uint16_t, private guest value, echoed in response567 * operation - uint8_t, operation code, XENSND_OP_???568 *569 * For all packets which use offset and length:570 * offset - uint32_t, read or write data offset within the shared buffer,571 * passed with XENSND_OP_OPEN request, octets,572 * [0; XENSND_OP_OPEN.buffer_sz - 1].573 * length - uint32_t, read or write data length, octets574 *575 * Request open - open a PCM stream for playback or capture:576 *577 * 0 1 2 3 octet578 * +----------------+----------------+----------------+----------------+579 * | id | XENSND_OP_OPEN | reserved | 4580 * +----------------+----------------+----------------+----------------+581 * | reserved | 8582 * +----------------+----------------+----------------+----------------+583 * | pcm_rate | 12584 * +----------------+----------------+----------------+----------------+585 * | pcm_format | pcm_channels | reserved | 16586 * +----------------+----------------+----------------+----------------+587 * | buffer_sz | 20588 * +----------------+----------------+----------------+----------------+589 * | gref_directory | 24590 * +----------------+----------------+----------------+----------------+591 * | period_sz | 28592 * +----------------+----------------+----------------+----------------+593 * | reserved | 32594 * +----------------+----------------+----------------+----------------+595 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|596 * +----------------+----------------+----------------+----------------+597 * | reserved | 64598 * +----------------+----------------+----------------+----------------+599 *600 * pcm_rate - uint32_t, stream data rate, Hz601 * pcm_format - uint8_t, XENSND_PCM_FORMAT_XXX value602 * pcm_channels - uint8_t, number of channels of this stream,603 * [channels-min; channels-max]604 * buffer_sz - uint32_t, buffer size to be allocated, octets605 * period_sz - uint32_t, event period size, octets606 * This is the requested value of the period at which frontend would607 * like to receive XENSND_EVT_CUR_POS notifications from the backend when608 * stream position advances during playback/capture.609 * It shows how many octets are expected to be played/captured before610 * sending such an event.611 * If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend.612 *613 * gref_directory - grant_ref_t, a reference to the first shared page614 * describing shared buffer references. At least one page exists. If shared615 * buffer size (buffer_sz) exceeds what can be addressed by this single page,616 * then reference to the next page must be supplied (see gref_dir_next_page617 * below)618 */619 620struct xensnd_open_req {621 uint32_t pcm_rate;622 uint8_t pcm_format;623 uint8_t pcm_channels;624 uint16_t reserved;625 uint32_t buffer_sz;626 grant_ref_t gref_directory;627 uint32_t period_sz;628};629 630/*631 * Shared page for XENSND_OP_OPEN buffer descriptor (gref_directory in the632 * request) employs a list of pages, describing all pages of the shared data633 * buffer:634 * 0 1 2 3 octet635 * +----------------+----------------+----------------+----------------+636 * | gref_dir_next_page | 4637 * +----------------+----------------+----------------+----------------+638 * | gref[0] | 8639 * +----------------+----------------+----------------+----------------+640 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|641 * +----------------+----------------+----------------+----------------+642 * | gref[i] | i*4+8643 * +----------------+----------------+----------------+----------------+644 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|645 * +----------------+----------------+----------------+----------------+646 * | gref[N - 1] | N*4+8647 * +----------------+----------------+----------------+----------------+648 *649 * gref_dir_next_page - grant_ref_t, reference to the next page describing650 * page directory. Must be 0 if there are no more pages in the list.651 * gref[i] - grant_ref_t, reference to a shared page of the buffer652 * allocated at XENSND_OP_OPEN653 *654 * Number of grant_ref_t entries in the whole page directory is not655 * passed, but instead can be calculated as:656 * num_grefs_total = (XENSND_OP_OPEN.buffer_sz + XEN_PAGE_SIZE - 1) /657 * XEN_PAGE_SIZE658 */659 660struct xensnd_page_directory {661 grant_ref_t gref_dir_next_page;662 grant_ref_t gref[];663};664 665/*666 * Request close - close an opened pcm stream:667 * 0 1 2 3 octet668 * +----------------+----------------+----------------+----------------+669 * | id | XENSND_OP_CLOSE| reserved | 4670 * +----------------+----------------+----------------+----------------+671 * | reserved | 8672 * +----------------+----------------+----------------+----------------+673 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|674 * +----------------+----------------+----------------+----------------+675 * | reserved | 64676 * +----------------+----------------+----------------+----------------+677 *678 * Request read/write - used for read (for capture) or write (for playback):679 * 0 1 2 3 octet680 * +----------------+----------------+----------------+----------------+681 * | id | operation | reserved | 4682 * +----------------+----------------+----------------+----------------+683 * | reserved | 8684 * +----------------+----------------+----------------+----------------+685 * | offset | 12686 * +----------------+----------------+----------------+----------------+687 * | length | 16688 * +----------------+----------------+----------------+----------------+689 * | reserved | 20690 * +----------------+----------------+----------------+----------------+691 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|692 * +----------------+----------------+----------------+----------------+693 * | reserved | 64694 * +----------------+----------------+----------------+----------------+695 *696 * operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write697 */698 699struct xensnd_rw_req {700 uint32_t offset;701 uint32_t length;702};703 704/*705 * Request set/get volume - set/get channels' volume of the stream given:706 * 0 1 2 3 octet707 * +----------------+----------------+----------------+----------------+708 * | id | operation | reserved | 4709 * +----------------+----------------+----------------+----------------+710 * | reserved | 8711 * +----------------+----------------+----------------+----------------+712 * | offset | 12713 * +----------------+----------------+----------------+----------------+714 * | length | 16715 * +----------------+----------------+----------------+----------------+716 * | reserved | 20717 * +----------------+----------------+----------------+----------------+718 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|719 * +----------------+----------------+----------------+----------------+720 * | reserved | 64721 * +----------------+----------------+----------------+----------------+722 *723 * operation - XENSND_OP_SET_VOLUME for volume set724 * or XENSND_OP_GET_VOLUME for volume get725 * Buffer passed with XENSND_OP_OPEN is used to exchange volume726 * values:727 *728 * 0 1 2 3 octet729 * +----------------+----------------+----------------+----------------+730 * | channel[0] | 4731 * +----------------+----------------+----------------+----------------+732 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|733 * +----------------+----------------+----------------+----------------+734 * | channel[i] | i*4735 * +----------------+----------------+----------------+----------------+736 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|737 * +----------------+----------------+----------------+----------------+738 * | channel[N - 1] | (N-1)*4739 * +----------------+----------------+----------------+----------------+740 *741 * N = XENSND_OP_OPEN.pcm_channels742 * i - uint8_t, index of a channel743 * channel[i] - sint32_t, volume of i-th channel744 * Volume is expressed as a signed value in steps of 0.001 dB,745 * while 0 being 0 dB.746 *747 * Request mute/unmute - mute/unmute stream:748 * 0 1 2 3 octet749 * +----------------+----------------+----------------+----------------+750 * | id | operation | reserved | 4751 * +----------------+----------------+----------------+----------------+752 * | reserved | 8753 * +----------------+----------------+----------------+----------------+754 * | offset | 12755 * +----------------+----------------+----------------+----------------+756 * | length | 16757 * +----------------+----------------+----------------+----------------+758 * | reserved | 20759 * +----------------+----------------+----------------+----------------+760 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|761 * +----------------+----------------+----------------+----------------+762 * | reserved | 64763 * +----------------+----------------+----------------+----------------+764 *765 * operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute766 * Buffer passed with XENSND_OP_OPEN is used to exchange mute/unmute767 * values:768 *769 * 0 octet770 * +----------------+----------------+----------------+----------------+771 * | channel[0] | 4772 * +----------------+----------------+----------------+----------------+773 * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|774 * +----------------+----------------+----------------+----------------+775 * | channel[i] | i*4776 * +----------------+----------------+----------------+----------------+777 * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|778 * +----------------+----------------+----------------+----------------+779 * | channel[N - 1] | (N-1)*4780 * +----------------+----------------+----------------+----------------+781 *782 * N = XENSND_OP_OPEN.pcm_channels783 * i - uint8_t, index of a channel784 * channel[i] - uint8_t, non-zero if i-th channel needs to be muted/unmuted785 *786 *------------------------------------ N.B. -----------------------------------787 *788 * The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME,789 * XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE.790 *791 * Request stream running state change - trigger PCM stream running state792 * to start, stop, pause or resume:793 *794 * 0 1 2 3 octet795 * +----------------+----------------+----------------+----------------+796 * | id | _OP_TRIGGER | reserved | 4797 * +----------------+----------------+----------------+----------------+798 * | reserved | 8799 * +----------------+----------------+----------------+----------------+800 * | type | reserved | 12801 * +----------------+----------------+----------------+----------------+802 * | reserved | 16803 * +----------------+----------------+----------------+----------------+804 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|805 * +----------------+----------------+----------------+----------------+806 * | reserved | 64807 * +----------------+----------------+----------------+----------------+808 *809 * type - uint8_t, XENSND_OP_TRIGGER_XXX value810 */811 812struct xensnd_trigger_req {813 uint8_t type;814};815 816/*817 * Request stream parameter ranges: request intervals and818 * masks of supported ranges for stream configuration values.819 *820 * Sound device configuration for a particular stream is a limited subset821 * of the multidimensional configuration available on XenStore, e.g.822 * once the frame rate has been selected there is a limited supported range823 * for sample rates becomes available (which might be the same set configured824 * on XenStore or less). For example, selecting 96kHz sample rate may limit825 * number of channels available for such configuration from 4 to 2, etc.826 * Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration827 * space making it possible to iteratively get the final stream configuration,828 * used in XENSND_OP_OPEN request.829 *830 * See response format for this request.831 *832 * 0 1 2 3 octet833 * +----------------+----------------+----------------+----------------+834 * | id | _HW_PARAM_QUERY| reserved | 4835 * +----------------+----------------+----------------+----------------+836 * | reserved | 8837 * +----------------+----------------+----------------+----------------+838 * | formats mask low 32-bit | 12839 * +----------------+----------------+----------------+----------------+840 * | formats mask high 32-bit | 16841 * +----------------+----------------+----------------+----------------+842 * | min rate | 20843 * +----------------+----------------+----------------+----------------+844 * | max rate | 24845 * +----------------+----------------+----------------+----------------+846 * | min channels | 28847 * +----------------+----------------+----------------+----------------+848 * | max channels | 32849 * +----------------+----------------+----------------+----------------+850 * | min buffer frames | 36851 * +----------------+----------------+----------------+----------------+852 * | max buffer frames | 40853 * +----------------+----------------+----------------+----------------+854 * | min period frames | 44855 * +----------------+----------------+----------------+----------------+856 * | max period frames | 48857 * +----------------+----------------+----------------+----------------+858 * | reserved | 52859 * +----------------+----------------+----------------+----------------+860 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|861 * +----------------+----------------+----------------+----------------+862 * | reserved | 64863 * +----------------+----------------+----------------+----------------+864 *865 * formats - uint64_t, bit mask representing values of the parameter866 * made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values867 *868 * For interval parameters:869 * min - uint32_t, minimum value of the parameter870 * max - uint32_t, maximum value of the parameter871 *872 * Frame is defined as a product of the number of channels by the873 * number of octets per one sample.874 */875 876struct xensnd_query_hw_param {877 uint64_t formats;878 struct {879 uint32_t min;880 uint32_t max;881 } rates;882 struct {883 uint32_t min;884 uint32_t max;885 } channels;886 struct {887 uint32_t min;888 uint32_t max;889 } buffer;890 struct {891 uint32_t min;892 uint32_t max;893 } period;894};895 896/*897 *---------------------------------- Responses --------------------------------898 *899 * All response packets have the same length (64 octets)900 *901 * All response packets have common header:902 * 0 1 2 3 octet903 * +----------------+----------------+----------------+----------------+904 * | id | operation | reserved | 4905 * +----------------+----------------+----------------+----------------+906 * | status | 8907 * +----------------+----------------+----------------+----------------+908 *909 * id - uint16_t, copied from the request910 * operation - uint8_t, XENSND_OP_* - copied from request911 * status - int32_t, response status, zero on success and -XEN_EXX on failure912 *913 *914 * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:915 * 0 1 2 3 octet916 * +----------------+----------------+----------------+----------------+917 * | id | operation | reserved | 4918 * +----------------+----------------+----------------+----------------+919 * | status | 8920 * +----------------+----------------+----------------+----------------+921 * | formats mask low 32-bit | 12922 * +----------------+----------------+----------------+----------------+923 * | formats mask high 32-bit | 16924 * +----------------+----------------+----------------+----------------+925 * | min rate | 20926 * +----------------+----------------+----------------+----------------+927 * | max rate | 24928 * +----------------+----------------+----------------+----------------+929 * | min channels | 28930 * +----------------+----------------+----------------+----------------+931 * | max channels | 32932 * +----------------+----------------+----------------+----------------+933 * | min buffer frames | 36934 * +----------------+----------------+----------------+----------------+935 * | max buffer frames | 40936 * +----------------+----------------+----------------+----------------+937 * | min period frames | 44938 * +----------------+----------------+----------------+----------------+939 * | max period frames | 48940 * +----------------+----------------+----------------+----------------+941 * | reserved | 52942 * +----------------+----------------+----------------+----------------+943 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|944 * +----------------+----------------+----------------+----------------+945 * | reserved | 64946 * +----------------+----------------+----------------+----------------+947 *948 * Meaning of the values in this response is the same as for949 * XENSND_OP_HW_PARAM_QUERY request.950 */951 952/*953 *----------------------------------- Events ----------------------------------954 *955 * Events are sent via shared page allocated by the front and propagated by956 * evt-event-channel/evt-ring-ref XenStore entries957 * All event packets have the same length (64 octets)958 * All event packets have common header:959 * 0 1 2 3 octet960 * +----------------+----------------+----------------+----------------+961 * | id | type | reserved | 4962 * +----------------+----------------+----------------+----------------+963 * | reserved | 8964 * +----------------+----------------+----------------+----------------+965 *966 * id - uint16_t, event id, may be used by front967 * type - uint8_t, type of the event968 *969 *970 * Current stream position - event from back to front when stream's971 * playback/capture position has advanced:972 * 0 1 2 3 octet973 * +----------------+----------------+----------------+----------------+974 * | id | _EVT_CUR_POS | reserved | 4975 * +----------------+----------------+----------------+----------------+976 * | reserved | 8977 * +----------------+----------------+----------------+----------------+978 * | position low 32-bit | 12979 * +----------------+----------------+----------------+----------------+980 * | position high 32-bit | 16981 * +----------------+----------------+----------------+----------------+982 * | reserved | 20983 * +----------------+----------------+----------------+----------------+984 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|985 * +----------------+----------------+----------------+----------------+986 * | reserved | 64987 * +----------------+----------------+----------------+----------------+988 *989 * position - current value of stream's playback/capture position, octets990 *991 */992 993struct xensnd_cur_pos_evt {994 uint64_t position;995};996 997struct xensnd_req {998 uint16_t id;999 uint8_t operation;1000 uint8_t reserved[5];1001 union {1002 struct xensnd_open_req open;1003 struct xensnd_rw_req rw;1004 struct xensnd_trigger_req trigger;1005 struct xensnd_query_hw_param hw_param;1006 uint8_t reserved[56];1007 } op;1008};1009 1010struct xensnd_resp {1011 uint16_t id;1012 uint8_t operation;1013 uint8_t reserved;1014 int32_t status;1015 union {1016 struct xensnd_query_hw_param hw_param;1017 uint8_t reserved1[56];1018 } resp;1019};1020 1021struct xensnd_evt {1022 uint16_t id;1023 uint8_t type;1024 uint8_t reserved[5];1025 union {1026 struct xensnd_cur_pos_evt cur_pos;1027 uint8_t reserved[56];1028 } op;1029};1030 1031DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp);1032 1033/*1034 ******************************************************************************1035 * Back to front events delivery1036 ******************************************************************************1037 * In order to deliver asynchronous events from back to front a shared page is1038 * allocated by front and its granted reference propagated to back via1039 * XenStore entries (evt-ring-ref/evt-event-channel).1040 * This page has a common header used by both front and back to synchronize1041 * access and control event's ring buffer, while back being a producer of the1042 * events and front being a consumer. The rest of the page after the header1043 * is used for event packets.1044 *1045 * Upon reception of an event(s) front may confirm its reception1046 * for either each event, group of events or none.1047 */1048 1049struct xensnd_event_page {1050 uint32_t in_cons;1051 uint32_t in_prod;1052 uint8_t reserved[56];1053};1054 1055#define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE1056#define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page))1057#define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS)1058#define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt))1059#define XENSND_IN_RING(page) \1060 ((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS))1061#define XENSND_IN_RING_REF(page, idx) \1062 (XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN])1063 1064#endif /* __XEN_PUBLIC_IO_SNDIF_H__ */1065