1065 lines
47 KiB
C
1065 lines
47 KiB
C
/* SPDX-License-Identifier: MIT */
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/******************************************************************************
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* sndif.h
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*
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* Unified sound-device I/O interface for Xen guest OSes.
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*
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* Copyright (C) 2013-2015 GlobalLogic Inc.
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* Copyright (C) 2016-2017 EPAM Systems Inc.
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*
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* Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
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* Oleksandr Grytsov <oleksandr_grytsov@epam.com>
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* Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
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* Iurii Konovalenko <iurii.konovalenko@globallogic.com>
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*/
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#ifndef __XEN_PUBLIC_IO_SNDIF_H__
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#define __XEN_PUBLIC_IO_SNDIF_H__
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#include "ring.h"
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#include "../grant_table.h"
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/*
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******************************************************************************
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* Protocol version
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******************************************************************************
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*/
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#define XENSND_PROTOCOL_VERSION 2
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/*
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******************************************************************************
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* Feature and Parameter Negotiation
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******************************************************************************
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*
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* Front->back notifications: when enqueuing a new request, sending a
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* notification can be made conditional on xensnd_req (i.e., the generic
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* hold-off mechanism provided by the ring macros). Backends must set
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* xensnd_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()).
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*
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* Back->front notifications: when enqueuing a new response, sending a
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* notification can be made conditional on xensnd_resp (i.e., the generic
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* hold-off mechanism provided by the ring macros). Frontends must set
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* xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
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*
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* The two halves of a para-virtual sound card driver utilize nodes within
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* XenStore to communicate capabilities and to negotiate operating parameters.
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* This section enumerates these nodes which reside in the respective front and
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* backend portions of XenStore, following the XenBus convention.
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*
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* All data in XenStore is stored as strings. Nodes specifying numeric
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* values are encoded in decimal. Integer value ranges listed below are
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* expressed as fixed sized integer types capable of storing the conversion
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* of a properly formated node string, without loss of information.
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*
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******************************************************************************
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* Example configuration
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******************************************************************************
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*
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* Note: depending on the use-case backend can expose more sound cards and
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* PCM devices/streams than the underlying HW physically has by employing
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* SW mixers, configuring virtual sound streams, channels etc.
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*
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* This is an example of backend and frontend configuration:
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*
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*--------------------------------- Backend -----------------------------------
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*
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* /local/domain/0/backend/vsnd/1/0/frontend-id = "1"
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* /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0"
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* /local/domain/0/backend/vsnd/1/0/state = "4"
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* /local/domain/0/backend/vsnd/1/0/versions = "1,2"
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*
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*--------------------------------- Frontend ----------------------------------
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*
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* /local/domain/1/device/vsnd/0/backend-id = "0"
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* /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0"
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* /local/domain/1/device/vsnd/0/state = "4"
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* /local/domain/1/device/vsnd/0/version = "1"
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*
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*----------------------------- Card configuration ----------------------------
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*
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* /local/domain/1/device/vsnd/0/short-name = "Card short name"
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* /local/domain/1/device/vsnd/0/long-name = "Card long name"
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* /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000"
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* /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be"
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* /local/domain/1/device/vsnd/0/buffer-size = "262144"
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*
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*------------------------------- PCM device 0 --------------------------------
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*
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* /local/domain/1/device/vsnd/0/0/name = "General analog"
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* /local/domain/1/device/vsnd/0/0/channels-max = "5"
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*
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*----------------------------- Stream 0, playback ----------------------------
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*
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* /local/domain/1/device/vsnd/0/0/0/type = "p"
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* /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8"
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* /local/domain/1/device/vsnd/0/0/0/unique-id = "0"
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*
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* /local/domain/1/device/vsnd/0/0/0/ring-ref = "386"
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* /local/domain/1/device/vsnd/0/0/0/event-channel = "15"
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* /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386"
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* /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215"
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*
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*------------------------------ Stream 1, capture ----------------------------
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*
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* /local/domain/1/device/vsnd/0/0/1/type = "c"
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* /local/domain/1/device/vsnd/0/0/1/channels-max = "2"
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* /local/domain/1/device/vsnd/0/0/1/unique-id = "1"
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*
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* /local/domain/1/device/vsnd/0/0/1/ring-ref = "384"
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* /local/domain/1/device/vsnd/0/0/1/event-channel = "13"
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* /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384"
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* /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213"
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*
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*------------------------------- PCM device 1 --------------------------------
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*
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* /local/domain/1/device/vsnd/0/1/name = "HDMI-0"
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* /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100"
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*
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*------------------------------ Stream 0, capture ----------------------------
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*
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* /local/domain/1/device/vsnd/0/1/0/type = "c"
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* /local/domain/1/device/vsnd/0/1/0/unique-id = "2"
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*
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* /local/domain/1/device/vsnd/0/1/0/ring-ref = "387"
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* /local/domain/1/device/vsnd/0/1/0/event-channel = "151"
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* /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387"
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* /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351"
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*
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*------------------------------- PCM device 2 --------------------------------
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*
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* /local/domain/1/device/vsnd/0/2/name = "SPDIF"
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*
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*----------------------------- Stream 0, playback ----------------------------
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*
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* /local/domain/1/device/vsnd/0/2/0/type = "p"
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* /local/domain/1/device/vsnd/0/2/0/unique-id = "3"
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*
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* /local/domain/1/device/vsnd/0/2/0/ring-ref = "389"
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* /local/domain/1/device/vsnd/0/2/0/event-channel = "152"
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* /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389"
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* /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452"
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*
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******************************************************************************
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* Backend XenBus Nodes
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******************************************************************************
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*
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*----------------------------- Protocol version ------------------------------
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*
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* versions
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* Values: <string>
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*
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* List of XENSND_LIST_SEPARATOR separated protocol versions supported
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* by the backend. For example "1,2,3".
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*
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******************************************************************************
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* Frontend XenBus Nodes
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******************************************************************************
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*
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*-------------------------------- Addressing ---------------------------------
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*
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* dom-id
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* Values: <uint16_t>
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*
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* Domain identifier.
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*
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* dev-id
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* Values: <uint16_t>
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*
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* Device identifier.
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*
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* pcm-dev-idx
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* Values: <uint8_t>
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*
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* Zero based contigous index of the PCM device.
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*
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* stream-idx
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* Values: <uint8_t>
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*
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* Zero based contigous index of the stream of the PCM device.
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*
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* The following pattern is used for addressing:
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* /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/...
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*
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*----------------------------- Protocol version ------------------------------
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*
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* version
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* Values: <string>
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*
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* Protocol version, chosen among the ones supported by the backend.
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*
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*------------------------------- PCM settings --------------------------------
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*
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* Every virtualized sound frontend has a set of PCM devices and streams, each
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* could be individually configured. Part of the PCM configuration can be
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* defined at higher level of the hierarchy and be fully or partially re-used
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* by the underlying layers. These configuration values are:
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* o number of channels (min/max)
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* o supported sample rates
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* o supported sample formats.
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* E.g. one can define these values for the whole card, device or stream.
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* Every underlying layer in turn can re-define some or all of them to better
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* fit its needs. For example, card may define number of channels to be
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* in [1; 8] range, and some particular stream may be limited to [1; 2] only.
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* The rule is that the underlying layer must be a subset of the upper layer
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* range.
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*
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* channels-min
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* Values: <uint8_t>
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*
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* The minimum amount of channels that is supported, [1; channels-max].
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* Optional, if not set or omitted a value of 1 is used.
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*
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* channels-max
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* Values: <uint8_t>
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*
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* The maximum amount of channels that is supported.
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* Must be at least <channels-min>.
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*
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* sample-rates
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* Values: <list of uint32_t>
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*
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* List of supported sample rates separated by XENSND_LIST_SEPARATOR.
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* Sample rates are expressed as a list of decimal values w/o any
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* ordering requirement.
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*
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* sample-formats
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* Values: <list of XENSND_PCM_FORMAT_XXX_STR>
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*
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* List of supported sample formats separated by XENSND_LIST_SEPARATOR.
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* Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length.
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*
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* buffer-size
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* Values: <uint32_t>
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*
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* The maximum size in octets of the buffer to allocate per stream.
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*
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*----------------------- Virtual sound card settings -------------------------
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* short-name
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* Values: <char[32]>
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*
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* Short name of the virtual sound card. Optional.
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*
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* long-name
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* Values: <char[80]>
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*
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* Long name of the virtual sound card. Optional.
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*
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*----------------------------- Device settings -------------------------------
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* name
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* Values: <char[80]>
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*
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* Name of the sound device within the virtual sound card. Optional.
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*
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*----------------------------- Stream settings -------------------------------
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*
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* type
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* Values: "p", "c"
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*
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* Stream type: "p" - playback stream, "c" - capture stream
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*
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* If both capture and playback are needed then two streams need to be
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* defined under the same device.
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*
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* unique-id
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* Values: <string>
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*
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* After stream initialization it is assigned a unique ID, so every
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* stream of the frontend can be identified by the backend by this ID.
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* This can be UUID or such.
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*
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*-------------------- Stream Request Transport Parameters --------------------
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*
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* event-channel
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* Values: <uint32_t>
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*
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* The identifier of the Xen event channel used to signal activity
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* in the ring buffer.
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*
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* ring-ref
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* Values: <uint32_t>
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*
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* The Xen grant reference granting permission for the backend to map
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* a sole page in a single page sized ring buffer.
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*
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*--------------------- Stream Event Transport Parameters ---------------------
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*
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* This communication path is used to deliver asynchronous events from backend
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* to frontend, set up per stream.
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*
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* evt-event-channel
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* Values: <uint32_t>
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*
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* The identifier of the Xen event channel used to signal activity
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* in the ring buffer.
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*
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* evt-ring-ref
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* Values: <uint32_t>
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*
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* The Xen grant reference granting permission for the backend to map
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* a sole page in a single page sized ring buffer.
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*
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******************************************************************************
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* STATE DIAGRAMS
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******************************************************************************
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*
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* Tool stack creates front and back state nodes with initial state
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* XenbusStateInitialising.
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* Tool stack creates and sets up frontend sound configuration nodes per domain.
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*
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* Front Back
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* ================================= =====================================
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* XenbusStateInitialising XenbusStateInitialising
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* o Query backend device identification
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* data.
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* o Open and validate backend device.
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* |
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* |
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* V
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* XenbusStateInitWait
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*
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* o Query frontend configuration
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* o Allocate and initialize
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* event channels per configured
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* playback/capture stream.
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* o Publish transport parameters
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* that will be in effect during
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* this connection.
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* |
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* |
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* V
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* XenbusStateInitialised
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*
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* o Query frontend transport parameters.
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* o Connect to the event channels.
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* |
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* |
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* V
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* XenbusStateConnected
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*
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* o Create and initialize OS
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* virtual sound device instances
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* as per configuration.
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* |
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* |
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* V
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* XenbusStateConnected
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*
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* XenbusStateUnknown
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* XenbusStateClosed
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* XenbusStateClosing
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* o Remove virtual sound device
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* o Remove event channels
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* |
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* |
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* V
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* XenbusStateClosed
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*
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*------------------------------- Recovery flow -------------------------------
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*
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* In case of frontend unrecoverable errors backend handles that as
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* if frontend goes into the XenbusStateClosed state.
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*
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* In case of backend unrecoverable errors frontend tries removing
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* the virtualized device. If this is possible at the moment of error,
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* then frontend goes into the XenbusStateInitialising state and is ready for
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* new connection with backend. If the virtualized device is still in use and
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* cannot be removed, then frontend goes into the XenbusStateReconfiguring state
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* until either the virtualized device removed or backend initiates a new
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* connection. On the virtualized device removal frontend goes into the
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* XenbusStateInitialising state.
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*
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* Note on XenbusStateReconfiguring state of the frontend: if backend has
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* unrecoverable errors then frontend cannot send requests to the backend
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* and thus cannot provide functionality of the virtualized device anymore.
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* After backend is back to normal the virtualized device may still hold some
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* state: configuration in use, allocated buffers, client application state etc.
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* So, in most cases, this will require frontend to implement complex recovery
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* reconnect logic. Instead, by going into XenbusStateReconfiguring state,
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* frontend will make sure no new clients of the virtualized device are
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* accepted, allow existing client(s) to exit gracefully by signaling error
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* state etc.
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* Once all the clients are gone frontend can reinitialize the virtualized
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* device and get into XenbusStateInitialising state again signaling the
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* backend that a new connection can be made.
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*
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* There are multiple conditions possible under which frontend will go from
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* XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS
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* specific. For example:
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* 1. The underlying OS framework may provide callbacks to signal that the last
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* client of the virtualized device has gone and the device can be removed
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* 2. Frontend can schedule a deferred work (timer/tasklet/workqueue)
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* to periodically check if this is the right time to re-try removal of
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* the virtualized device.
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* 3. By any other means.
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*
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******************************************************************************
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* PCM FORMATS
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******************************************************************************
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*
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* XENSND_PCM_FORMAT_<format>[_<endian>]
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*
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* format: <S/U/F><bits> or <name>
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* S - signed, U - unsigned, F - float
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* bits - 8, 16, 24, 32
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* name - MU_LAW, GSM, etc.
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*
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* endian: <LE/BE>, may be absent
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* LE - Little endian, BE - Big endian
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*/
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#define XENSND_PCM_FORMAT_S8 0
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#define XENSND_PCM_FORMAT_U8 1
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#define XENSND_PCM_FORMAT_S16_LE 2
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#define XENSND_PCM_FORMAT_S16_BE 3
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#define XENSND_PCM_FORMAT_U16_LE 4
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#define XENSND_PCM_FORMAT_U16_BE 5
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#define XENSND_PCM_FORMAT_S24_LE 6
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#define XENSND_PCM_FORMAT_S24_BE 7
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#define XENSND_PCM_FORMAT_U24_LE 8
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#define XENSND_PCM_FORMAT_U24_BE 9
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#define XENSND_PCM_FORMAT_S32_LE 10
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#define XENSND_PCM_FORMAT_S32_BE 11
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#define XENSND_PCM_FORMAT_U32_LE 12
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#define XENSND_PCM_FORMAT_U32_BE 13
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#define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */
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#define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */
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#define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */
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#define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */
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#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18
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#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19
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#define XENSND_PCM_FORMAT_MU_LAW 20
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#define XENSND_PCM_FORMAT_A_LAW 21
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#define XENSND_PCM_FORMAT_IMA_ADPCM 22
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#define XENSND_PCM_FORMAT_MPEG 23
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#define XENSND_PCM_FORMAT_GSM 24
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/*
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******************************************************************************
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* REQUEST CODES
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******************************************************************************
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*/
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#define XENSND_OP_OPEN 0
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#define XENSND_OP_CLOSE 1
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#define XENSND_OP_READ 2
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#define XENSND_OP_WRITE 3
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#define XENSND_OP_SET_VOLUME 4
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#define XENSND_OP_GET_VOLUME 5
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#define XENSND_OP_MUTE 6
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#define XENSND_OP_UNMUTE 7
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#define XENSND_OP_TRIGGER 8
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#define XENSND_OP_HW_PARAM_QUERY 9
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#define XENSND_OP_TRIGGER_START 0
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#define XENSND_OP_TRIGGER_PAUSE 1
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#define XENSND_OP_TRIGGER_STOP 2
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#define XENSND_OP_TRIGGER_RESUME 3
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/*
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******************************************************************************
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* EVENT CODES
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******************************************************************************
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*/
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#define XENSND_EVT_CUR_POS 0
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/*
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******************************************************************************
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* XENSTORE FIELD AND PATH NAME STRINGS, HELPERS
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******************************************************************************
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*/
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#define XENSND_DRIVER_NAME "vsnd"
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#define XENSND_LIST_SEPARATOR ","
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/* Field names */
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#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_EVT_RING_REF "evt-ring-ref"
|
|
#define XENSND_FIELD_EVT_EVT_CHNL "evt-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 (64 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
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | period_sz | 28
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 32
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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
|
|
* period_sz - uint32_t, event period size, octets
|
|
* This is the requested value of the period at which frontend would
|
|
* like to receive XENSND_EVT_CUR_POS notifications from the backend when
|
|
* stream position advances during playback/capture.
|
|
* It shows how many octets are expected to be played/captured before
|
|
* sending such an event.
|
|
* If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend.
|
|
*
|
|
* 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;
|
|
uint32_t period_sz;
|
|
};
|
|
|
|
/*
|
|
* 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 | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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 | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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 | 20
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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 | 20
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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.
|
|
*
|
|
* Request stream running state change - trigger PCM stream running state
|
|
* to start, stop, pause or resume:
|
|
*
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | _OP_TRIGGER | reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | type | reserved | 12
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 16
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* type - uint8_t, XENSND_OP_TRIGGER_XXX value
|
|
*/
|
|
|
|
struct xensnd_trigger_req {
|
|
uint8_t type;
|
|
};
|
|
|
|
/*
|
|
* Request stream parameter ranges: request intervals and
|
|
* masks of supported ranges for stream configuration values.
|
|
*
|
|
* Sound device configuration for a particular stream is a limited subset
|
|
* of the multidimensional configuration available on XenStore, e.g.
|
|
* once the frame rate has been selected there is a limited supported range
|
|
* for sample rates becomes available (which might be the same set configured
|
|
* on XenStore or less). For example, selecting 96kHz sample rate may limit
|
|
* number of channels available for such configuration from 4 to 2, etc.
|
|
* Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration
|
|
* space making it possible to iteratively get the final stream configuration,
|
|
* used in XENSND_OP_OPEN request.
|
|
*
|
|
* See response format for this request.
|
|
*
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | _HW_PARAM_QUERY| reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | formats mask low 32-bit | 12
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | formats mask high 32-bit | 16
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min rate | 20
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max rate | 24
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min channels | 28
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max channels | 32
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min buffer frames | 36
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max buffer frames | 40
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min period frames | 44
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max period frames | 48
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 52
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* formats - uint64_t, bit mask representing values of the parameter
|
|
* made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values
|
|
*
|
|
* For interval parameters:
|
|
* min - uint32_t, minimum value of the parameter
|
|
* max - uint32_t, maximum value of the parameter
|
|
*
|
|
* Frame is defined as a product of the number of channels by the
|
|
* number of octets per one sample.
|
|
*/
|
|
|
|
struct xensnd_query_hw_param {
|
|
uint64_t formats;
|
|
struct {
|
|
uint32_t min;
|
|
uint32_t max;
|
|
} rates;
|
|
struct {
|
|
uint32_t min;
|
|
uint32_t max;
|
|
} channels;
|
|
struct {
|
|
uint32_t min;
|
|
uint32_t max;
|
|
} buffer;
|
|
struct {
|
|
uint32_t min;
|
|
uint32_t max;
|
|
} period;
|
|
};
|
|
|
|
/*
|
|
*---------------------------------- Responses --------------------------------
|
|
*
|
|
* All response packets have the same length (64 octets)
|
|
*
|
|
* All response packets have common header:
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | operation | reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | status | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* 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
|
|
*
|
|
*
|
|
* HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | operation | reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | status | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | formats mask low 32-bit | 12
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | formats mask high 32-bit | 16
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min rate | 20
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max rate | 24
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min channels | 28
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max channels | 32
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min buffer frames | 36
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max buffer frames | 40
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | min period frames | 44
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | max period frames | 48
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 52
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* Meaning of the values in this response is the same as for
|
|
* XENSND_OP_HW_PARAM_QUERY request.
|
|
*/
|
|
|
|
/*
|
|
*----------------------------------- Events ----------------------------------
|
|
*
|
|
* Events are sent via shared page allocated by the front and propagated by
|
|
* evt-event-channel/evt-ring-ref XenStore entries
|
|
* All event packets have the same length (64 octets)
|
|
* All event packets have common header:
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | type | reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* id - uint16_t, event id, may be used by front
|
|
* type - uint8_t, type of the event
|
|
*
|
|
*
|
|
* Current stream position - event from back to front when stream's
|
|
* playback/capture position has advanced:
|
|
* 0 1 2 3 octet
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | id | _EVT_CUR_POS | reserved | 4
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 8
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | position low 32-bit | 12
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | position high 32-bit | 16
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 20
|
|
* +----------------+----------------+----------------+----------------+
|
|
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
* +----------------+----------------+----------------+----------------+
|
|
* | reserved | 64
|
|
* +----------------+----------------+----------------+----------------+
|
|
*
|
|
* position - current value of stream's playback/capture position, octets
|
|
*
|
|
*/
|
|
|
|
struct xensnd_cur_pos_evt {
|
|
uint64_t position;
|
|
};
|
|
|
|
struct xensnd_req {
|
|
uint16_t id;
|
|
uint8_t operation;
|
|
uint8_t reserved[5];
|
|
union {
|
|
struct xensnd_open_req open;
|
|
struct xensnd_rw_req rw;
|
|
struct xensnd_trigger_req trigger;
|
|
struct xensnd_query_hw_param hw_param;
|
|
uint8_t reserved[56];
|
|
} op;
|
|
};
|
|
|
|
struct xensnd_resp {
|
|
uint16_t id;
|
|
uint8_t operation;
|
|
uint8_t reserved;
|
|
int32_t status;
|
|
union {
|
|
struct xensnd_query_hw_param hw_param;
|
|
uint8_t reserved1[56];
|
|
} resp;
|
|
};
|
|
|
|
struct xensnd_evt {
|
|
uint16_t id;
|
|
uint8_t type;
|
|
uint8_t reserved[5];
|
|
union {
|
|
struct xensnd_cur_pos_evt cur_pos;
|
|
uint8_t reserved[56];
|
|
} op;
|
|
};
|
|
|
|
DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp);
|
|
|
|
/*
|
|
******************************************************************************
|
|
* Back to front events delivery
|
|
******************************************************************************
|
|
* In order to deliver asynchronous events from back to front a shared page is
|
|
* allocated by front and its granted reference propagated to back via
|
|
* XenStore entries (evt-ring-ref/evt-event-channel).
|
|
* This page has a common header used by both front and back to synchronize
|
|
* access and control event's ring buffer, while back being a producer of the
|
|
* events and front being a consumer. The rest of the page after the header
|
|
* is used for event packets.
|
|
*
|
|
* Upon reception of an event(s) front may confirm its reception
|
|
* for either each event, group of events or none.
|
|
*/
|
|
|
|
struct xensnd_event_page {
|
|
uint32_t in_cons;
|
|
uint32_t in_prod;
|
|
uint8_t reserved[56];
|
|
};
|
|
|
|
#define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE
|
|
#define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page))
|
|
#define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS)
|
|
#define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt))
|
|
#define XENSND_IN_RING(page) \
|
|
((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS))
|
|
#define XENSND_IN_RING_REF(page, idx) \
|
|
(XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN])
|
|
|
|
#endif /* __XEN_PUBLIC_IO_SNDIF_H__ */
|