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1081 lines
48 KiB
1081 lines
48 KiB
/****************************************************************************** |
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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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* Permission is hereby granted, free of charge, to any person obtaining a copy |
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* of this software and associated documentation files (the "Software"), to |
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* deal in the Software without restriction, including without limitation the |
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* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
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* sell copies of the Software, and to permit persons to whom the Software is |
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* furnished to do so, subject to the following conditions: |
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* |
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* The above copyright notice and this permission notice shall be included in |
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* all copies or substantial portions of the Software. |
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* |
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
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* DEALINGS IN THE SOFTWARE. |
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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 <[email protected]> |
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* Oleksandr Grytsov <[email protected]> |
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* Oleksandr Dmytryshyn <[email protected]> |
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* Iurii Konovalenko <[email protected]> |
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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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****************************************************************************** |
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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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****************************************************************************** |
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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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|
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#define XENSND_LIST_SEPARATOR "," |
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/* Field names */ |
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#define XENSND_FIELD_BE_VERSIONS "versions" |
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#define XENSND_FIELD_FE_VERSION "version" |
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#define XENSND_FIELD_VCARD_SHORT_NAME "short-name" |
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#define XENSND_FIELD_VCARD_LONG_NAME "long-name" |
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#define XENSND_FIELD_RING_REF "ring-ref" |
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#define XENSND_FIELD_EVT_CHNL "event-channel" |
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#define XENSND_FIELD_EVT_RING_REF "evt-ring-ref" |
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#define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel" |
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#define XENSND_FIELD_DEVICE_NAME "name" |
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#define XENSND_FIELD_TYPE "type" |
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#define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id" |
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#define XENSND_FIELD_CHANNELS_MIN "channels-min" |
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#define XENSND_FIELD_CHANNELS_MAX "channels-max" |
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#define XENSND_FIELD_SAMPLE_RATES "sample-rates" |
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#define XENSND_FIELD_SAMPLE_FORMATS "sample-formats" |
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#define XENSND_FIELD_BUFFER_SIZE "buffer-size" |
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|
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/* Stream type field values. */ |
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#define XENSND_STREAM_TYPE_PLAYBACK "p" |
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#define XENSND_STREAM_TYPE_CAPTURE "c" |
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/* Sample rate max string length */ |
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#define XENSND_SAMPLE_RATE_MAX_LEN 11 |
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/* Sample format field values */ |
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#define XENSND_SAMPLE_FORMAT_MAX_LEN 24 |
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|
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#define XENSND_PCM_FORMAT_S8_STR "s8" |
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#define XENSND_PCM_FORMAT_U8_STR "u8" |
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#define XENSND_PCM_FORMAT_S16_LE_STR "s16_le" |
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#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; |
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int32_t status; |
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union { |
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struct xensnd_query_hw_param hw_param; |
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uint8_t reserved1[56]; |
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} resp; |
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}; |
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|
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struct xensnd_evt { |
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uint16_t id; |
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uint8_t type; |
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uint8_t reserved[5]; |
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union { |
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struct xensnd_cur_pos_evt cur_pos; |
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uint8_t reserved[56]; |
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} op; |
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}; |
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|
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DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp); |
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|
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/* |
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****************************************************************************** |
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* Back to front events delivery |
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****************************************************************************** |
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* In order to deliver asynchronous events from back to front a shared page is |
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* allocated by front and its granted reference propagated to back via |
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* XenStore entries (evt-ring-ref/evt-event-channel). |
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* This page has a common header used by both front and back to synchronize |
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* access and control event's ring buffer, while back being a producer of the |
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* events and front being a consumer. The rest of the page after the header |
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* is used for event packets. |
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* |
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* Upon reception of an event(s) front may confirm its reception |
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* for either each event, group of events or none. |
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*/ |
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|
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struct xensnd_event_page { |
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uint32_t in_cons; |
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uint32_t in_prod; |
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uint8_t reserved[56]; |
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}; |
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|
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#define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE |
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#define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page)) |
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#define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS) |
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#define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt)) |
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#define XENSND_IN_RING(page) \ |
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((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS)) |
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#define XENSND_IN_RING_REF(page, idx) \ |
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(XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN]) |
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|
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#endif /* __XEN_PUBLIC_IO_SNDIF_H__ */
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