| /****************************************************************************** | |
| * sndif.h | |
| * | |
| * Unified sound-device I/O interface for Xen guest OSes. | |
| * | |
| * Permission is hereby granted, free of charge, to any person obtaining a copy | |
| * of this software and associated documentation files (the "Software"), to | |
| * deal in the Software without restriction, including without limitation the | |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or | |
| * sell copies of the Software, and to permit persons to whom the Software is | |
| * furnished to do so, subject to the following conditions: | |
| * | |
| * The above copyright notice and this permission notice shall be included in | |
| * all copies or substantial portions of the Software. | |
| * | |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | |
| * DEALINGS IN THE SOFTWARE. | |
| * | |
| * Copyright (C) 2013-2015 GlobalLogic Inc. | |
| * Copyright (C) 2016-2017 EPAM Systems Inc. | |
| * | |
| * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> | |
| * Oleksandr Grytsov <oleksandr_grytsov@epam.com> | |
| * Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com> | |
| * Iurii Konovalenko <iurii.konovalenko@globallogic.com> | |
| */ | |
| #ifndef __XEN_PUBLIC_IO_SNDIF_H__ | |
| #define __XEN_PUBLIC_IO_SNDIF_H__ | |
| #include "ring.h" | |
| #include "../grant_table.h" | |
| /* | |
| ****************************************************************************** | |
| * Feature and Parameter Negotiation | |
| ****************************************************************************** | |
| * | |
| * Front->back notifications: when enqueuing a new request, sending a | |
| * notification can be made conditional on xensnd_req (i.e., the generic | |
| * hold-off mechanism provided by the ring macros). Backends must set | |
| * xensnd_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()). | |
| * | |
| * Back->front notifications: when enqueuing a new response, sending a | |
| * notification can be made conditional on xensnd_resp (i.e., the generic | |
| * hold-off mechanism provided by the ring macros). Frontends must set | |
| * xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()). | |
| * | |
| * The two halves of a para-virtual sound card driver utilize nodes within | |
| * XenStore to communicate capabilities and to negotiate operating parameters. | |
| * This section enumerates these nodes which reside in the respective front and | |
| * backend portions of XenStore, following the XenBus convention. | |
| * | |
| * All data in XenStore is stored as strings. Nodes specifying numeric | |
| * values are encoded in decimal. Integer value ranges listed below are | |
| * expressed as fixed sized integer types capable of storing the conversion | |
| * of a properly formated node string, without loss of information. | |
| * | |
| ****************************************************************************** | |
| * Example configuration | |
| ****************************************************************************** | |
| * | |
| * Note: depending on the use-case backend can expose more sound cards and | |
| * PCM devices/streams than the underlying HW physically has by employing | |
| * SW mixers, configuring virtual sound streams, channels etc. | |
| * | |
| * This is an example of backend and frontend configuration: | |
| * | |
| *--------------------------------- Backend ----------------------------------- | |
| * | |
| * /local/domain/0/backend/vsnd/1/0/frontend-id = "1" | |
| * /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0" | |
| * /local/domain/0/backend/vsnd/1/0/state = "4" | |
| * /local/domain/0/backend/vsnd/1/0/versions = "1,2" | |
| * | |
| *--------------------------------- Frontend ---------------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/backend-id = "0" | |
| * /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0" | |
| * /local/domain/1/device/vsnd/0/state = "4" | |
| * /local/domain/1/device/vsnd/0/version = "1" | |
| * | |
| *----------------------------- Card configuration ---------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/short-name = "Card short name" | |
| * /local/domain/1/device/vsnd/0/long-name = "Card long name" | |
| * /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000" | |
| * /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be" | |
| * /local/domain/1/device/vsnd/0/buffer-size = "262144" | |
| * | |
| *------------------------------- PCM device 0 -------------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/0/name = "General analog" | |
| * /local/domain/1/device/vsnd/0/0/channels-max = "5" | |
| * | |
| *----------------------------- Stream 0, playback ---------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/0/0/type = "p" | |
| * /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8" | |
| * /local/domain/1/device/vsnd/0/0/0/unique-id = "0" | |
| * | |
| * /local/domain/1/device/vsnd/0/0/0/ring-ref = "386" | |
| * /local/domain/1/device/vsnd/0/0/0/event-channel = "15" | |
| * | |
| *------------------------------ Stream 1, capture ---------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/0/1/type = "c" | |
| * /local/domain/1/device/vsnd/0/0/1/channels-max = "2" | |
| * /local/domain/1/device/vsnd/0/0/1/unique-id = "1" | |
| * | |
| * /local/domain/1/device/vsnd/0/0/1/ring-ref = "384" | |
| * /local/domain/1/device/vsnd/0/0/1/event-channel = "13" | |
| * | |
| *------------------------------- PCM device 1 -------------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/1/name = "HDMI-0" | |
| * /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100" | |
| * | |
| *------------------------------ Stream 0, capture ---------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/1/0/type = "c" | |
| * /local/domain/1/device/vsnd/0/1/0/unique-id = "2" | |
| * | |
| * /local/domain/1/device/vsnd/0/1/0/ring-ref = "387" | |
| * /local/domain/1/device/vsnd/0/1/0/event-channel = "151" | |
| * | |
| *------------------------------- PCM device 2 -------------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/2/name = "SPDIF" | |
| * | |
| *----------------------------- Stream 0, playback ---------------------------- | |
| * | |
| * /local/domain/1/device/vsnd/0/2/0/type = "p" | |
| * /local/domain/1/device/vsnd/0/2/0/unique-id = "3" | |
| * | |
| * /local/domain/1/device/vsnd/0/2/0/ring-ref = "389" | |
| * /local/domain/1/device/vsnd/0/2/0/event-channel = "152" | |
| * | |
| ****************************************************************************** | |
| * Backend XenBus Nodes | |
| ****************************************************************************** | |
| * | |
| *----------------------------- Protocol version ------------------------------ | |
| * | |
| * versions | |
| * Values: <string> | |
| * | |
| * List of XENSND_LIST_SEPARATOR separated protocol versions supported | |
| * by the backend. For example "1,2,3". | |
| * | |
| ****************************************************************************** | |
| * Frontend XenBus Nodes | |
| ****************************************************************************** | |
| * | |
| *-------------------------------- Addressing --------------------------------- | |
| * | |
| * dom-id | |
| * Values: <uint16_t> | |
| * | |
| * Domain identifier. | |
| * | |
| * dev-id | |
| * Values: <uint16_t> | |
| * | |
| * Device identifier. | |
| * | |
| * pcm-dev-idx | |
| * Values: <uint8_t> | |
| * | |
| * Zero based contigous index of the PCM device. | |
| * | |
| * stream-idx | |
| * Values: <uint8_t> | |
| * | |
| * Zero based contigous index of the stream of the PCM device. | |
| * | |
| * The following pattern is used for addressing: | |
| * /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/... | |
| * | |
| *----------------------------- Protocol version ------------------------------ | |
| * | |
| * version | |
| * Values: <string> | |
| * | |
| * Protocol version, chosen among the ones supported by the backend. | |
| * | |
| *------------------------------- PCM settings -------------------------------- | |
| * | |
| * Every virtualized sound frontend has a set of PCM devices and streams, each | |
| * could be individually configured. Part of the PCM configuration can be | |
| * defined at higher level of the hierarchy and be fully or partially re-used | |
| * by the underlying layers. These configuration values are: | |
| * o number of channels (min/max) | |
| * o supported sample rates | |
| * o supported sample formats. | |
| * E.g. one can define these values for the whole card, device or stream. | |
| * Every underlying layer in turn can re-define some or all of them to better | |
| * fit its needs. For example, card may define number of channels to be | |
| * in [1; 8] range, and some particular stream may be limited to [1; 2] only. | |
| * The rule is that the underlying layer must be a subset of the upper layer | |
| * range. | |
| * | |
| * channels-min | |
| * Values: <uint8_t> | |
| * | |
| * The minimum amount of channels that is supported, [1; channels-max]. | |
| * Optional, if not set or omitted a value of 1 is used. | |
| * | |
| * channels-max | |
| * Values: <uint8_t> | |
| * | |
| * The maximum amount of channels that is supported. | |
| * Must be at least <channels-min>. | |
| * | |
| * sample-rates | |
| * Values: <list of uint32_t> | |
| * | |
| * List of supported sample rates separated by XENSND_LIST_SEPARATOR. | |
| * Sample rates are expressed as a list of decimal values w/o any | |
| * ordering requirement. | |
| * | |
| * sample-formats | |
| * Values: <list of XENSND_PCM_FORMAT_XXX_STR> | |
| * | |
| * List of supported sample formats separated by XENSND_LIST_SEPARATOR. | |
| * Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length. | |
| * | |
| * buffer-size | |
| * Values: <uint32_t> | |
| * | |
| * The maximum size in octets of the buffer to allocate per stream. | |
| * | |
| *----------------------- Virtual sound card settings ------------------------- | |
| * short-name | |
| * Values: <char[32]> | |
| * | |
| * Short name of the virtual sound card. Optional. | |
| * | |
| * long-name | |
| * Values: <char[80]> | |
| * | |
| * Long name of the virtual sound card. Optional. | |
| * | |
| *----------------------------- Device settings ------------------------------- | |
| * name | |
| * Values: <char[80]> | |
| * | |
| * Name of the sound device within the virtual sound card. Optional. | |
| * | |
| *----------------------------- Stream settings ------------------------------- | |
| * | |
| * type | |
| * Values: "p", "c" | |
| * | |
| * Stream type: "p" - playback stream, "c" - capture stream | |
| * | |
| * If both capture and playback are needed then two streams need to be | |
| * defined under the same device. | |
| * | |
| * unique-id | |
| * Values: <uint32_t> | |
| * | |
| * After stream initialization it is assigned a unique ID (within the front | |
| * driver), so every stream of the frontend can be identified by the | |
| * backend by this ID. This is not equal to stream-idx as the later is | |
| * zero based within the device, but this index is contigous within the | |
| * driver. | |
| * | |
| *-------------------- Stream Request Transport Parameters -------------------- | |
| * | |
| * event-channel | |
| * Values: <uint32_t> | |
| * | |
| * The identifier of the Xen event channel used to signal activity | |
| * in the ring buffer. | |
| * | |
| * ring-ref | |
| * Values: <uint32_t> | |
| * | |
| * The Xen grant reference granting permission for the backend to map | |
| * a sole page in a single page sized ring buffer. | |
| * | |
| ****************************************************************************** | |
| * STATE DIAGRAMS | |
| ****************************************************************************** | |
| * | |
| * Tool stack creates front and back state nodes with initial state | |
| * XenbusStateInitialising. | |
| * Tool stack creates and sets up frontend sound configuration nodes per domain. | |
| * | |
| * Front Back | |
| * ================================= ===================================== | |
| * XenbusStateInitialising XenbusStateInitialising | |
| * o Query backend device identification | |
| * data. | |
| * o Open and validate backend device. | |
| * | | |
| * | | |
| * V | |
| * XenbusStateInitWait | |
| * | |
| * o Query frontend configuration | |
| * o Allocate and initialize | |
| * event channels per configured | |
| * playback/capture stream. | |
| * o Publish transport parameters | |
| * that will be in effect during | |
| * this connection. | |
| * | | |
| * | | |
| * V | |
| * XenbusStateInitialised | |
| * | |
| * o Query frontend transport parameters. | |
| * o Connect to the event channels. | |
| * | | |
| * | | |
| * V | |
| * XenbusStateConnected | |
| * | |
| * o Create and initialize OS | |
| * virtual sound device instances | |
| * as per configuration. | |
| * | | |
| * | | |
| * V | |
| * XenbusStateConnected | |
| * | |
| * XenbusStateUnknown | |
| * XenbusStateClosed | |
| * XenbusStateClosing | |
| * o Remove virtual sound device | |
| * o Remove event channels | |
| * | | |
| * | | |
| * V | |
| * XenbusStateClosed | |
| * | |
| *------------------------------- Recovery flow ------------------------------- | |
| * | |
| * In case of frontend unrecoverable errors backend handles that as | |
| * if frontend goes into the XenbusStateClosed state. | |
| * | |
| * In case of backend unrecoverable errors frontend tries removing | |
| * the virtualized device. If this is possible at the moment of error, | |
| * then frontend goes into the XenbusStateInitialising state and is ready for | |
| * new connection with backend. If the virtualized device is still in use and | |
| * cannot be removed, then frontend goes into the XenbusStateReconfiguring state | |
| * until either the virtualized device removed or backend initiates a new | |
| * connection. On the virtualized device removal frontend goes into the | |
| * XenbusStateInitialising state. | |
| * | |
| * Note on XenbusStateReconfiguring state of the frontend: if backend has | |
| * unrecoverable errors then frontend cannot send requests to the backend | |
| * and thus cannot provide functionality of the virtualized device anymore. | |
| * After backend is back to normal the virtualized device may still hold some | |
| * state: configuration in use, allocated buffers, client application state etc. | |
| * So, in most cases, this will require frontend to implement complex recovery | |
| * reconnect logic. Instead, by going into XenbusStateReconfiguring state, | |
| * frontend will make sure no new clients of the virtualized device are | |
| * accepted, allow existing client(s) to exit gracefully by signaling error | |
| * state etc. | |
| * Once all the clients are gone frontend can reinitialize the virtualized | |
| * device and get into XenbusStateInitialising state again signaling the | |
| * backend that a new connection can be made. | |
| * | |
| * There are multiple conditions possible under which frontend will go from | |
| * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS | |
| * specific. For example: | |
| * 1. The underlying OS framework may provide callbacks to signal that the last | |
| * client of the virtualized device has gone and the device can be removed | |
| * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue) | |
| * to periodically check if this is the right time to re-try removal of | |
| * the virtualized device. | |
| * 3. By any other means. | |
| * | |
| ****************************************************************************** | |
| * PCM FORMATS | |
| ****************************************************************************** | |
| * | |
| * XENSND_PCM_FORMAT_<format>[_<endian>] | |
| * | |
| * format: <S/U/F><bits> or <name> | |
| * S - signed, U - unsigned, F - float | |
| * bits - 8, 16, 24, 32 | |
| * name - MU_LAW, GSM, etc. | |
| * | |
| * endian: <LE/BE>, may be absent | |
| * LE - Little endian, BE - Big endian | |
| */ | |
| #define XENSND_PCM_FORMAT_S8 0 | |
| #define XENSND_PCM_FORMAT_U8 1 | |
| #define XENSND_PCM_FORMAT_S16_LE 2 | |
| #define XENSND_PCM_FORMAT_S16_BE 3 | |
| #define XENSND_PCM_FORMAT_U16_LE 4 | |
| #define XENSND_PCM_FORMAT_U16_BE 5 | |
| #define XENSND_PCM_FORMAT_S24_LE 6 | |
| #define XENSND_PCM_FORMAT_S24_BE 7 | |
| #define XENSND_PCM_FORMAT_U24_LE 8 | |
| #define XENSND_PCM_FORMAT_U24_BE 9 | |
| #define XENSND_PCM_FORMAT_S32_LE 10 | |
| #define XENSND_PCM_FORMAT_S32_BE 11 | |
| #define XENSND_PCM_FORMAT_U32_LE 12 | |
| #define XENSND_PCM_FORMAT_U32_BE 13 | |
| #define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */ | |
| #define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */ | |
| #define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */ | |
| #define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */ | |
| #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18 | |
| #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19 | |
| #define XENSND_PCM_FORMAT_MU_LAW 20 | |
| #define XENSND_PCM_FORMAT_A_LAW 21 | |
| #define XENSND_PCM_FORMAT_IMA_ADPCM 22 | |
| #define XENSND_PCM_FORMAT_MPEG 23 | |
| #define XENSND_PCM_FORMAT_GSM 24 | |
| /* | |
| ****************************************************************************** | |
| * REQUEST CODES | |
| ****************************************************************************** | |
| */ | |
| #define XENSND_OP_OPEN 0 | |
| #define XENSND_OP_CLOSE 1 | |
| #define XENSND_OP_READ 2 | |
| #define XENSND_OP_WRITE 3 | |
| #define XENSND_OP_SET_VOLUME 4 | |
| #define XENSND_OP_GET_VOLUME 5 | |
| #define XENSND_OP_MUTE 6 | |
| #define XENSND_OP_UNMUTE 7 | |
| /* | |
| ****************************************************************************** | |
| * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS | |
| ****************************************************************************** | |
| */ | |
| #define XENSND_DRIVER_NAME "vsnd" | |
| #define XENSND_LIST_SEPARATOR "," | |
| /* Field names */ | |
| #define XENSND_FIELD_BE_VERSIONS "versions" | |
| #define XENSND_FIELD_FE_VERSION "version" | |
| #define XENSND_FIELD_VCARD_SHORT_NAME "short-name" | |
| #define XENSND_FIELD_VCARD_LONG_NAME "long-name" | |
| #define XENSND_FIELD_RING_REF "ring-ref" | |
| #define XENSND_FIELD_EVT_CHNL "event-channel" | |
| #define XENSND_FIELD_DEVICE_NAME "name" | |
| #define XENSND_FIELD_TYPE "type" | |
| #define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id" | |
| #define XENSND_FIELD_CHANNELS_MIN "channels-min" | |
| #define XENSND_FIELD_CHANNELS_MAX "channels-max" | |
| #define XENSND_FIELD_SAMPLE_RATES "sample-rates" | |
| #define XENSND_FIELD_SAMPLE_FORMATS "sample-formats" | |
| #define XENSND_FIELD_BUFFER_SIZE "buffer-size" | |
| /* Stream type field values. */ | |
| #define XENSND_STREAM_TYPE_PLAYBACK "p" | |
| #define XENSND_STREAM_TYPE_CAPTURE "c" | |
| /* Sample rate max string length */ | |
| #define XENSND_SAMPLE_RATE_MAX_LEN 11 | |
| /* Sample format field values */ | |
| #define XENSND_SAMPLE_FORMAT_MAX_LEN 24 | |
| #define XENSND_PCM_FORMAT_S8_STR "s8" | |
| #define XENSND_PCM_FORMAT_U8_STR "u8" | |
| #define XENSND_PCM_FORMAT_S16_LE_STR "s16_le" | |
| #define XENSND_PCM_FORMAT_S16_BE_STR "s16_be" | |
| #define XENSND_PCM_FORMAT_U16_LE_STR "u16_le" | |
| #define XENSND_PCM_FORMAT_U16_BE_STR "u16_be" | |
| #define XENSND_PCM_FORMAT_S24_LE_STR "s24_le" | |
| #define XENSND_PCM_FORMAT_S24_BE_STR "s24_be" | |
| #define XENSND_PCM_FORMAT_U24_LE_STR "u24_le" | |
| #define XENSND_PCM_FORMAT_U24_BE_STR "u24_be" | |
| #define XENSND_PCM_FORMAT_S32_LE_STR "s32_le" | |
| #define XENSND_PCM_FORMAT_S32_BE_STR "s32_be" | |
| #define XENSND_PCM_FORMAT_U32_LE_STR "u32_le" | |
| #define XENSND_PCM_FORMAT_U32_BE_STR "u32_be" | |
| #define XENSND_PCM_FORMAT_F32_LE_STR "float_le" | |
| #define XENSND_PCM_FORMAT_F32_BE_STR "float_be" | |
| #define XENSND_PCM_FORMAT_F64_LE_STR "float64_le" | |
| #define XENSND_PCM_FORMAT_F64_BE_STR "float64_be" | |
| #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR "iec958_subframe_le" | |
| #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR "iec958_subframe_be" | |
| #define XENSND_PCM_FORMAT_MU_LAW_STR "mu_law" | |
| #define XENSND_PCM_FORMAT_A_LAW_STR "a_law" | |
| #define XENSND_PCM_FORMAT_IMA_ADPCM_STR "ima_adpcm" | |
| #define XENSND_PCM_FORMAT_MPEG_STR "mpeg" | |
| #define XENSND_PCM_FORMAT_GSM_STR "gsm" | |
| /* | |
| ****************************************************************************** | |
| * STATUS RETURN CODES | |
| ****************************************************************************** | |
| * | |
| * Status return code is zero on success and -XEN_EXX on failure. | |
| * | |
| ****************************************************************************** | |
| * Assumptions | |
| ****************************************************************************** | |
| * o usage of grant reference 0 as invalid grant reference: | |
| * grant reference 0 is valid, but never exposed to a PV driver, | |
| * because of the fact it is already in use/reserved by the PV console. | |
| * o all references in this document to page sizes must be treated | |
| * as pages of size XEN_PAGE_SIZE unless otherwise noted. | |
| * | |
| ****************************************************************************** | |
| * Description of the protocol between frontend and backend driver | |
| ****************************************************************************** | |
| * | |
| * The two halves of a Para-virtual sound driver communicate with | |
| * each other using shared pages and event channels. | |
| * Shared page contains a ring with request/response packets. | |
| * | |
| * Packets, used for input/output operations, e.g. read/write, set/get volume, | |
| * etc., provide offset/length fields in order to allow asynchronous protocol | |
| * operation with buffer space sharing: part of the buffer allocated at | |
| * XENSND_OP_OPEN can be used for audio samples and part, for example, | |
| * for volume control. | |
| * | |
| * All reserved fields in the structures below must be 0. | |
| * | |
| *---------------------------------- Requests --------------------------------- | |
| * | |
| * All request packets have the same length (32 octets) | |
| * All request packets have common header: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | operation | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * id - uint16_t, private guest value, echoed in response | |
| * operation - uint8_t, operation code, XENSND_OP_??? | |
| * | |
| * For all packets which use offset and length: | |
| * offset - uint32_t, read or write data offset within the shared buffer, | |
| * passed with XENSND_OP_OPEN request, octets, | |
| * [0; XENSND_OP_OPEN.buffer_sz - 1]. | |
| * length - uint32_t, read or write data length, octets | |
| * | |
| * Request open - open a PCM stream for playback or capture: | |
| * | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | XENSND_OP_OPEN | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | pcm_rate | 12 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | pcm_format | pcm_channels | reserved | 16 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | buffer_sz | 20 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | gref_directory | 24 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 28 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * pcm_rate - uint32_t, stream data rate, Hz | |
| * pcm_format - uint8_t, XENSND_PCM_FORMAT_XXX value | |
| * pcm_channels - uint8_t, number of channels of this stream, | |
| * [channels-min; channels-max] | |
| * buffer_sz - uint32_t, buffer size to be allocated, octets | |
| * gref_directory - grant_ref_t, a reference to the first shared page | |
| * describing shared buffer references. At least one page exists. If shared | |
| * buffer size (buffer_sz) exceeds what can be addressed by this single page, | |
| * then reference to the next page must be supplied (see gref_dir_next_page | |
| * below) | |
| */ | |
| struct xensnd_open_req { | |
| uint32_t pcm_rate; | |
| uint8_t pcm_format; | |
| uint8_t pcm_channels; | |
| uint16_t reserved; | |
| uint32_t buffer_sz; | |
| grant_ref_t gref_directory; | |
| }; | |
| /* | |
| * Shared page for XENSND_OP_OPEN buffer descriptor (gref_directory in the | |
| * request) employs a list of pages, describing all pages of the shared data | |
| * buffer: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | gref_dir_next_page | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | gref[0] | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | gref[i] | i*4+8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | gref[N - 1] | N*4+8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * gref_dir_next_page - grant_ref_t, reference to the next page describing | |
| * page directory. Must be 0 if there are no more pages in the list. | |
| * gref[i] - grant_ref_t, reference to a shared page of the buffer | |
| * allocated at XENSND_OP_OPEN | |
| * | |
| * Number of grant_ref_t entries in the whole page directory is not | |
| * passed, but instead can be calculated as: | |
| * num_grefs_total = (XENSND_OP_OPEN.buffer_sz + XEN_PAGE_SIZE - 1) / | |
| * XEN_PAGE_SIZE | |
| */ | |
| struct xensnd_page_directory { | |
| grant_ref_t gref_dir_next_page; | |
| grant_ref_t gref[1]; /* Variable length */ | |
| }; | |
| /* | |
| * Request close - close an opened pcm stream: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | XENSND_OP_CLOSE| reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * Request read/write - used for read (for capture) or write (for playback): | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | operation | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | offset | 12 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | length | 16 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 20 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write | |
| */ | |
| struct xensnd_rw_req { | |
| uint32_t offset; | |
| uint32_t length; | |
| }; | |
| /* | |
| * Request set/get volume - set/get channels' volume of the stream given: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | operation | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | offset | 12 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | length | 16 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * operation - XENSND_OP_SET_VOLUME for volume set | |
| * or XENSND_OP_GET_VOLUME for volume get | |
| * Buffer passed with XENSND_OP_OPEN is used to exchange volume | |
| * values: | |
| * | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[0] | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[i] | i*4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[N - 1] | (N-1)*4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * N = XENSND_OP_OPEN.pcm_channels | |
| * i - uint8_t, index of a channel | |
| * channel[i] - sint32_t, volume of i-th channel | |
| * Volume is expressed as a signed value in steps of 0.001 dB, | |
| * while 0 being 0 dB. | |
| * | |
| * Request mute/unmute - mute/unmute stream: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | operation | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | offset | 12 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | length | 16 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute | |
| * Buffer passed with XENSND_OP_OPEN is used to exchange mute/unmute | |
| * values: | |
| * | |
| * 0 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[0] | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[i] | i*4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | channel[N - 1] | (N-1)*4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * N = XENSND_OP_OPEN.pcm_channels | |
| * i - uint8_t, index of a channel | |
| * channel[i] - uint8_t, non-zero if i-th channel needs to be muted/unmuted | |
| * | |
| *------------------------------------ N.B. ----------------------------------- | |
| * | |
| * The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME, | |
| * XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE. | |
| */ | |
| /* | |
| *---------------------------------- Responses -------------------------------- | |
| * | |
| * All response packets have the same length (32 octets) | |
| * | |
| * Response for all requests: | |
| * 0 1 2 3 octet | |
| * +----------------+----------------+----------------+----------------+ | |
| * | id | operation | reserved | 4 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | status | 8 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 12 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 32 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | |
| * id - uint16_t, copied from the request | |
| * operation - uint8_t, XENSND_OP_* - copied from request | |
| * status - int32_t, response status, zero on success and -XEN_EXX on failure | |
| */ | |
| struct xensnd_req { | |
| uint16_t id; | |
| uint8_t operation; | |
| uint8_t reserved[5]; | |
| union { | |
| struct xensnd_open_req open; | |
| struct xensnd_rw_req rw; | |
| uint8_t reserved[24]; | |
| } op; | |
| }; | |
| struct xensnd_resp { | |
| uint16_t id; | |
| uint8_t operation; | |
| uint8_t reserved; | |
| int32_t status; | |
| uint8_t reserved1[24]; | |
| }; | |
| DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp); | |
| #endif /* __XEN_PUBLIC_IO_SNDIF_H__ */ |