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| 1 | /* SPDX-License-Identifier: MIT */ |
|---|---|
| 2 | /****************************************************************************** |
| 3 | * sndif.h |
| 4 | * |
| 5 | * Unified sound-device I/O interface for Xen guest OSes. |
| 6 | * |
| 7 | * Copyright (C) 2013-2015 GlobalLogic Inc. |
| 8 | * Copyright (C) 2016-2017 EPAM Systems Inc. |
| 9 | * |
| 10 | * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> |
| 11 | * Oleksandr Grytsov <oleksandr_grytsov@epam.com> |
| 12 | * Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com> |
| 13 | * Iurii Konovalenko <iurii.konovalenko@globallogic.com> |
| 14 | */ |
| 15 | |
| 16 | #ifndef __XEN_PUBLIC_IO_SNDIF_H__ |
| 17 | #define __XEN_PUBLIC_IO_SNDIF_H__ |
| 18 | |
| 19 | #include "ring.h" |
| 20 | #include "../grant_table.h" |
| 21 | |
| 22 | /* |
| 23 | ****************************************************************************** |
| 24 | * Protocol version |
| 25 | ****************************************************************************** |
| 26 | */ |
| 27 | #define XENSND_PROTOCOL_VERSION 2 |
| 28 | |
| 29 | /* |
| 30 | ****************************************************************************** |
| 31 | * Feature and Parameter Negotiation |
| 32 | ****************************************************************************** |
| 33 | * |
| 34 | * Front->back notifications: when enqueuing a new request, sending a |
| 35 | * notification can be made conditional on xensnd_req (i.e., the generic |
| 36 | * hold-off mechanism provided by the ring macros). Backends must set |
| 37 | * xensnd_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()). |
| 38 | * |
| 39 | * Back->front notifications: when enqueuing a new response, sending a |
| 40 | * notification can be made conditional on xensnd_resp (i.e., the generic |
| 41 | * hold-off mechanism provided by the ring macros). Frontends must set |
| 42 | * xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()). |
| 43 | * |
| 44 | * The two halves of a para-virtual sound card driver utilize nodes within |
| 45 | * XenStore to communicate capabilities and to negotiate operating parameters. |
| 46 | * This section enumerates these nodes which reside in the respective front and |
| 47 | * backend portions of XenStore, following the XenBus convention. |
| 48 | * |
| 49 | * All data in XenStore is stored as strings. Nodes specifying numeric |
| 50 | * values are encoded in decimal. Integer value ranges listed below are |
| 51 | * expressed as fixed sized integer types capable of storing the conversion |
| 52 | * of a properly formated node string, without loss of information. |
| 53 | * |
| 54 | ****************************************************************************** |
| 55 | * Example configuration |
| 56 | ****************************************************************************** |
| 57 | * |
| 58 | * Note: depending on the use-case backend can expose more sound cards and |
| 59 | * PCM devices/streams than the underlying HW physically has by employing |
| 60 | * SW mixers, configuring virtual sound streams, channels etc. |
| 61 | * |
| 62 | * This is an example of backend and frontend configuration: |
| 63 | * |
| 64 | *--------------------------------- Backend ----------------------------------- |
| 65 | * |
| 66 | * /local/domain/0/backend/vsnd/1/0/frontend-id = "1" |
| 67 | * /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0" |
| 68 | * /local/domain/0/backend/vsnd/1/0/state = "4" |
| 69 | * /local/domain/0/backend/vsnd/1/0/versions = "1,2" |
| 70 | * |
| 71 | *--------------------------------- Frontend ---------------------------------- |
| 72 | * |
| 73 | * /local/domain/1/device/vsnd/0/backend-id = "0" |
| 74 | * /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0" |
| 75 | * /local/domain/1/device/vsnd/0/state = "4" |
| 76 | * /local/domain/1/device/vsnd/0/version = "1" |
| 77 | * |
| 78 | *----------------------------- Card configuration ---------------------------- |
| 79 | * |
| 80 | * /local/domain/1/device/vsnd/0/short-name = "Card short name" |
| 81 | * /local/domain/1/device/vsnd/0/long-name = "Card long name" |
| 82 | * /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000" |
| 83 | * /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be" |
| 84 | * /local/domain/1/device/vsnd/0/buffer-size = "262144" |
| 85 | * |
| 86 | *------------------------------- PCM device 0 -------------------------------- |
| 87 | * |
| 88 | * /local/domain/1/device/vsnd/0/0/name = "General analog" |
| 89 | * /local/domain/1/device/vsnd/0/0/channels-max = "5" |
| 90 | * |
| 91 | *----------------------------- Stream 0, playback ---------------------------- |
| 92 | * |
| 93 | * /local/domain/1/device/vsnd/0/0/0/type = "p" |
| 94 | * /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8" |
| 95 | * /local/domain/1/device/vsnd/0/0/0/unique-id = "0" |
| 96 | * |
| 97 | * /local/domain/1/device/vsnd/0/0/0/ring-ref = "386" |
| 98 | * /local/domain/1/device/vsnd/0/0/0/event-channel = "15" |
| 99 | * /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386" |
| 100 | * /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215" |
| 101 | * |
| 102 | *------------------------------ Stream 1, capture ---------------------------- |
| 103 | * |
| 104 | * /local/domain/1/device/vsnd/0/0/1/type = "c" |
| 105 | * /local/domain/1/device/vsnd/0/0/1/channels-max = "2" |
| 106 | * /local/domain/1/device/vsnd/0/0/1/unique-id = "1" |
| 107 | * |
| 108 | * /local/domain/1/device/vsnd/0/0/1/ring-ref = "384" |
| 109 | * /local/domain/1/device/vsnd/0/0/1/event-channel = "13" |
| 110 | * /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384" |
| 111 | * /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213" |
| 112 | * |
| 113 | *------------------------------- PCM device 1 -------------------------------- |
| 114 | * |
| 115 | * /local/domain/1/device/vsnd/0/1/name = "HDMI-0" |
| 116 | * /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100" |
| 117 | * |
| 118 | *------------------------------ Stream 0, capture ---------------------------- |
| 119 | * |
| 120 | * /local/domain/1/device/vsnd/0/1/0/type = "c" |
| 121 | * /local/domain/1/device/vsnd/0/1/0/unique-id = "2" |
| 122 | * |
| 123 | * /local/domain/1/device/vsnd/0/1/0/ring-ref = "387" |
| 124 | * /local/domain/1/device/vsnd/0/1/0/event-channel = "151" |
| 125 | * /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387" |
| 126 | * /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351" |
| 127 | * |
| 128 | *------------------------------- PCM device 2 -------------------------------- |
| 129 | * |
| 130 | * /local/domain/1/device/vsnd/0/2/name = "SPDIF" |
| 131 | * |
| 132 | *----------------------------- Stream 0, playback ---------------------------- |
| 133 | * |
| 134 | * /local/domain/1/device/vsnd/0/2/0/type = "p" |
| 135 | * /local/domain/1/device/vsnd/0/2/0/unique-id = "3" |
| 136 | * |
| 137 | * /local/domain/1/device/vsnd/0/2/0/ring-ref = "389" |
| 138 | * /local/domain/1/device/vsnd/0/2/0/event-channel = "152" |
| 139 | * /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389" |
| 140 | * /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452" |
| 141 | * |
| 142 | ****************************************************************************** |
| 143 | * Backend XenBus Nodes |
| 144 | ****************************************************************************** |
| 145 | * |
| 146 | *----------------------------- Protocol version ------------------------------ |
| 147 | * |
| 148 | * versions |
| 149 | * Values: <string> |
| 150 | * |
| 151 | * List of XENSND_LIST_SEPARATOR separated protocol versions supported |
| 152 | * by the backend. For example "1,2,3". |
| 153 | * |
| 154 | ****************************************************************************** |
| 155 | * Frontend XenBus Nodes |
| 156 | ****************************************************************************** |
| 157 | * |
| 158 | *-------------------------------- Addressing --------------------------------- |
| 159 | * |
| 160 | * dom-id |
| 161 | * Values: <uint16_t> |
| 162 | * |
| 163 | * Domain identifier. |
| 164 | * |
| 165 | * dev-id |
| 166 | * Values: <uint16_t> |
| 167 | * |
| 168 | * Device identifier. |
| 169 | * |
| 170 | * pcm-dev-idx |
| 171 | * Values: <uint8_t> |
| 172 | * |
| 173 | * Zero based contigous index of the PCM device. |
| 174 | * |
| 175 | * stream-idx |
| 176 | * Values: <uint8_t> |
| 177 | * |
| 178 | * Zero based contigous index of the stream of the PCM device. |
| 179 | * |
| 180 | * The following pattern is used for addressing: |
| 181 | * /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/... |
| 182 | * |
| 183 | *----------------------------- Protocol version ------------------------------ |
| 184 | * |
| 185 | * version |
| 186 | * Values: <string> |
| 187 | * |
| 188 | * Protocol version, chosen among the ones supported by the backend. |
| 189 | * |
| 190 | *------------------------------- PCM settings -------------------------------- |
| 191 | * |
| 192 | * Every virtualized sound frontend has a set of PCM devices and streams, each |
| 193 | * could be individually configured. Part of the PCM configuration can be |
| 194 | * defined at higher level of the hierarchy and be fully or partially re-used |
| 195 | * by the underlying layers. These configuration values are: |
| 196 | * o number of channels (min/max) |
| 197 | * o supported sample rates |
| 198 | * o supported sample formats. |
| 199 | * E.g. one can define these values for the whole card, device or stream. |
| 200 | * Every underlying layer in turn can re-define some or all of them to better |
| 201 | * fit its needs. For example, card may define number of channels to be |
| 202 | * in [1; 8] range, and some particular stream may be limited to [1; 2] only. |
| 203 | * The rule is that the underlying layer must be a subset of the upper layer |
| 204 | * range. |
| 205 | * |
| 206 | * channels-min |
| 207 | * Values: <uint8_t> |
| 208 | * |
| 209 | * The minimum amount of channels that is supported, [1; channels-max]. |
| 210 | * Optional, if not set or omitted a value of 1 is used. |
| 211 | * |
| 212 | * channels-max |
| 213 | * Values: <uint8_t> |
| 214 | * |
| 215 | * The maximum amount of channels that is supported. |
| 216 | * Must be at least <channels-min>. |
| 217 | * |
| 218 | * sample-rates |
| 219 | * Values: <list of uint32_t> |
| 220 | * |
| 221 | * List of supported sample rates separated by XENSND_LIST_SEPARATOR. |
| 222 | * Sample rates are expressed as a list of decimal values w/o any |
| 223 | * ordering requirement. |
| 224 | * |
| 225 | * sample-formats |
| 226 | * Values: <list of XENSND_PCM_FORMAT_XXX_STR> |
| 227 | * |
| 228 | * List of supported sample formats separated by XENSND_LIST_SEPARATOR. |
| 229 | * Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length. |
| 230 | * |
| 231 | * buffer-size |
| 232 | * Values: <uint32_t> |
| 233 | * |
| 234 | * The maximum size in octets of the buffer to allocate per stream. |
| 235 | * |
| 236 | *----------------------- Virtual sound card settings ------------------------- |
| 237 | * short-name |
| 238 | * Values: <char[32]> |
| 239 | * |
| 240 | * Short name of the virtual sound card. Optional. |
| 241 | * |
| 242 | * long-name |
| 243 | * Values: <char[80]> |
| 244 | * |
| 245 | * Long name of the virtual sound card. Optional. |
| 246 | * |
| 247 | *----------------------------- Device settings ------------------------------- |
| 248 | * name |
| 249 | * Values: <char[80]> |
| 250 | * |
| 251 | * Name of the sound device within the virtual sound card. Optional. |
| 252 | * |
| 253 | *----------------------------- Stream settings ------------------------------- |
| 254 | * |
| 255 | * type |
| 256 | * Values: "p", "c" |
| 257 | * |
| 258 | * Stream type: "p" - playback stream, "c" - capture stream |
| 259 | * |
| 260 | * If both capture and playback are needed then two streams need to be |
| 261 | * defined under the same device. |
| 262 | * |
| 263 | * unique-id |
| 264 | * Values: <string> |
| 265 | * |
| 266 | * After stream initialization it is assigned a unique ID, so every |
| 267 | * stream of the frontend can be identified by the backend by this ID. |
| 268 | * This can be UUID or such. |
| 269 | * |
| 270 | *-------------------- Stream Request Transport Parameters -------------------- |
| 271 | * |
| 272 | * event-channel |
| 273 | * Values: <uint32_t> |
| 274 | * |
| 275 | * The identifier of the Xen event channel used to signal activity |
| 276 | * in the ring buffer. |
| 277 | * |
| 278 | * ring-ref |
| 279 | * Values: <uint32_t> |
| 280 | * |
| 281 | * The Xen grant reference granting permission for the backend to map |
| 282 | * a sole page in a single page sized ring buffer. |
| 283 | * |
| 284 | *--------------------- Stream Event Transport Parameters --------------------- |
| 285 | * |
| 286 | * This communication path is used to deliver asynchronous events from backend |
| 287 | * to frontend, set up per stream. |
| 288 | * |
| 289 | * evt-event-channel |
| 290 | * Values: <uint32_t> |
| 291 | * |
| 292 | * The identifier of the Xen event channel used to signal activity |
| 293 | * in the ring buffer. |
| 294 | * |
| 295 | * evt-ring-ref |
| 296 | * Values: <uint32_t> |
| 297 | * |
| 298 | * The Xen grant reference granting permission for the backend to map |
| 299 | * a sole page in a single page sized ring buffer. |
| 300 | * |
| 301 | ****************************************************************************** |
| 302 | * STATE DIAGRAMS |
| 303 | ****************************************************************************** |
| 304 | * |
| 305 | * Tool stack creates front and back state nodes with initial state |
| 306 | * XenbusStateInitialising. |
| 307 | * Tool stack creates and sets up frontend sound configuration nodes per domain. |
| 308 | * |
| 309 | * Front Back |
| 310 | * ================================= ===================================== |
| 311 | * XenbusStateInitialising XenbusStateInitialising |
| 312 | * o Query backend device identification |
| 313 | * data. |
| 314 | * o Open and validate backend device. |
| 315 | * | |
| 316 | * | |
| 317 | * V |
| 318 | * XenbusStateInitWait |
| 319 | * |
| 320 | * o Query frontend configuration |
| 321 | * o Allocate and initialize |
| 322 | * event channels per configured |
| 323 | * playback/capture stream. |
| 324 | * o Publish transport parameters |
| 325 | * that will be in effect during |
| 326 | * this connection. |
| 327 | * | |
| 328 | * | |
| 329 | * V |
| 330 | * XenbusStateInitialised |
| 331 | * |
| 332 | * o Query frontend transport parameters. |
| 333 | * o Connect to the event channels. |
| 334 | * | |
| 335 | * | |
| 336 | * V |
| 337 | * XenbusStateConnected |
| 338 | * |
| 339 | * o Create and initialize OS |
| 340 | * virtual sound device instances |
| 341 | * as per configuration. |
| 342 | * | |
| 343 | * | |
| 344 | * V |
| 345 | * XenbusStateConnected |
| 346 | * |
| 347 | * XenbusStateUnknown |
| 348 | * XenbusStateClosed |
| 349 | * XenbusStateClosing |
| 350 | * o Remove virtual sound device |
| 351 | * o Remove event channels |
| 352 | * | |
| 353 | * | |
| 354 | * V |
| 355 | * XenbusStateClosed |
| 356 | * |
| 357 | *------------------------------- Recovery flow ------------------------------- |
| 358 | * |
| 359 | * In case of frontend unrecoverable errors backend handles that as |
| 360 | * if frontend goes into the XenbusStateClosed state. |
| 361 | * |
| 362 | * In case of backend unrecoverable errors frontend tries removing |
| 363 | * the virtualized device. If this is possible at the moment of error, |
| 364 | * then frontend goes into the XenbusStateInitialising state and is ready for |
| 365 | * new connection with backend. If the virtualized device is still in use and |
| 366 | * cannot be removed, then frontend goes into the XenbusStateReconfiguring state |
| 367 | * until either the virtualized device removed or backend initiates a new |
| 368 | * connection. On the virtualized device removal frontend goes into the |
| 369 | * XenbusStateInitialising state. |
| 370 | * |
| 371 | * Note on XenbusStateReconfiguring state of the frontend: if backend has |
| 372 | * unrecoverable errors then frontend cannot send requests to the backend |
| 373 | * and thus cannot provide functionality of the virtualized device anymore. |
| 374 | * After backend is back to normal the virtualized device may still hold some |
| 375 | * state: configuration in use, allocated buffers, client application state etc. |
| 376 | * So, in most cases, this will require frontend to implement complex recovery |
| 377 | * reconnect logic. Instead, by going into XenbusStateReconfiguring state, |
| 378 | * frontend will make sure no new clients of the virtualized device are |
| 379 | * accepted, allow existing client(s) to exit gracefully by signaling error |
| 380 | * state etc. |
| 381 | * Once all the clients are gone frontend can reinitialize the virtualized |
| 382 | * device and get into XenbusStateInitialising state again signaling the |
| 383 | * backend that a new connection can be made. |
| 384 | * |
| 385 | * There are multiple conditions possible under which frontend will go from |
| 386 | * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS |
| 387 | * specific. For example: |
| 388 | * 1. The underlying OS framework may provide callbacks to signal that the last |
| 389 | * client of the virtualized device has gone and the device can be removed |
| 390 | * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue) |
| 391 | * to periodically check if this is the right time to re-try removal of |
| 392 | * the virtualized device. |
| 393 | * 3. By any other means. |
| 394 | * |
| 395 | ****************************************************************************** |
| 396 | * PCM FORMATS |
| 397 | ****************************************************************************** |
| 398 | * |
| 399 | * XENSND_PCM_FORMAT_<format>[_<endian>] |
| 400 | * |
| 401 | * format: <S/U/F><bits> or <name> |
| 402 | * S - signed, U - unsigned, F - float |
| 403 | * bits - 8, 16, 24, 32 |
| 404 | * name - MU_LAW, GSM, etc. |
| 405 | * |
| 406 | * endian: <LE/BE>, may be absent |
| 407 | * LE - Little endian, BE - Big endian |
| 408 | */ |
| 409 | #define XENSND_PCM_FORMAT_S8 0 |
| 410 | #define XENSND_PCM_FORMAT_U8 1 |
| 411 | #define XENSND_PCM_FORMAT_S16_LE 2 |
| 412 | #define XENSND_PCM_FORMAT_S16_BE 3 |
| 413 | #define XENSND_PCM_FORMAT_U16_LE 4 |
| 414 | #define XENSND_PCM_FORMAT_U16_BE 5 |
| 415 | #define XENSND_PCM_FORMAT_S24_LE 6 |
| 416 | #define XENSND_PCM_FORMAT_S24_BE 7 |
| 417 | #define XENSND_PCM_FORMAT_U24_LE 8 |
| 418 | #define XENSND_PCM_FORMAT_U24_BE 9 |
| 419 | #define XENSND_PCM_FORMAT_S32_LE 10 |
| 420 | #define XENSND_PCM_FORMAT_S32_BE 11 |
| 421 | #define XENSND_PCM_FORMAT_U32_LE 12 |
| 422 | #define XENSND_PCM_FORMAT_U32_BE 13 |
| 423 | #define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */ |
| 424 | #define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */ |
| 425 | #define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */ |
| 426 | #define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */ |
| 427 | #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18 |
| 428 | #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19 |
| 429 | #define XENSND_PCM_FORMAT_MU_LAW 20 |
| 430 | #define XENSND_PCM_FORMAT_A_LAW 21 |
| 431 | #define XENSND_PCM_FORMAT_IMA_ADPCM 22 |
| 432 | #define XENSND_PCM_FORMAT_MPEG 23 |
| 433 | #define XENSND_PCM_FORMAT_GSM 24 |
| 434 | |
| 435 | /* |
| 436 | ****************************************************************************** |
| 437 | * REQUEST CODES |
| 438 | ****************************************************************************** |
| 439 | */ |
| 440 | #define XENSND_OP_OPEN 0 |
| 441 | #define XENSND_OP_CLOSE 1 |
| 442 | #define XENSND_OP_READ 2 |
| 443 | #define XENSND_OP_WRITE 3 |
| 444 | #define XENSND_OP_SET_VOLUME 4 |
| 445 | #define XENSND_OP_GET_VOLUME 5 |
| 446 | #define XENSND_OP_MUTE 6 |
| 447 | #define XENSND_OP_UNMUTE 7 |
| 448 | #define XENSND_OP_TRIGGER 8 |
| 449 | #define XENSND_OP_HW_PARAM_QUERY 9 |
| 450 | |
| 451 | #define XENSND_OP_TRIGGER_START 0 |
| 452 | #define XENSND_OP_TRIGGER_PAUSE 1 |
| 453 | #define XENSND_OP_TRIGGER_STOP 2 |
| 454 | #define XENSND_OP_TRIGGER_RESUME 3 |
| 455 | |
| 456 | /* |
| 457 | ****************************************************************************** |
| 458 | * EVENT CODES |
| 459 | ****************************************************************************** |
| 460 | */ |
| 461 | #define XENSND_EVT_CUR_POS 0 |
| 462 | |
| 463 | /* |
| 464 | ****************************************************************************** |
| 465 | * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS |
| 466 | ****************************************************************************** |
| 467 | */ |
| 468 | #define XENSND_DRIVER_NAME "vsnd" |
| 469 | |
| 470 | #define XENSND_LIST_SEPARATOR "," |
| 471 | /* Field names */ |
| 472 | #define XENSND_FIELD_BE_VERSIONS "versions" |
| 473 | #define XENSND_FIELD_FE_VERSION "version" |
| 474 | #define XENSND_FIELD_VCARD_SHORT_NAME "short-name" |
| 475 | #define XENSND_FIELD_VCARD_LONG_NAME "long-name" |
| 476 | #define XENSND_FIELD_RING_REF "ring-ref" |
| 477 | #define XENSND_FIELD_EVT_CHNL "event-channel" |
| 478 | #define XENSND_FIELD_EVT_RING_REF "evt-ring-ref" |
| 479 | #define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel" |
| 480 | #define XENSND_FIELD_DEVICE_NAME "name" |
| 481 | #define XENSND_FIELD_TYPE "type" |
| 482 | #define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id" |
| 483 | #define XENSND_FIELD_CHANNELS_MIN "channels-min" |
| 484 | #define XENSND_FIELD_CHANNELS_MAX "channels-max" |
| 485 | #define XENSND_FIELD_SAMPLE_RATES "sample-rates" |
| 486 | #define XENSND_FIELD_SAMPLE_FORMATS "sample-formats" |
| 487 | #define XENSND_FIELD_BUFFER_SIZE "buffer-size" |
| 488 | |
| 489 | /* Stream type field values. */ |
| 490 | #define XENSND_STREAM_TYPE_PLAYBACK "p" |
| 491 | #define XENSND_STREAM_TYPE_CAPTURE "c" |
| 492 | /* Sample rate max string length */ |
| 493 | #define XENSND_SAMPLE_RATE_MAX_LEN 11 |
| 494 | /* Sample format field values */ |
| 495 | #define XENSND_SAMPLE_FORMAT_MAX_LEN 24 |
| 496 | |
| 497 | #define XENSND_PCM_FORMAT_S8_STR "s8" |
| 498 | #define XENSND_PCM_FORMAT_U8_STR "u8" |
| 499 | #define XENSND_PCM_FORMAT_S16_LE_STR "s16_le" |
| 500 | #define XENSND_PCM_FORMAT_S16_BE_STR "s16_be" |
| 501 | #define XENSND_PCM_FORMAT_U16_LE_STR "u16_le" |
| 502 | #define XENSND_PCM_FORMAT_U16_BE_STR "u16_be" |
| 503 | #define XENSND_PCM_FORMAT_S24_LE_STR "s24_le" |
| 504 | #define XENSND_PCM_FORMAT_S24_BE_STR "s24_be" |
| 505 | #define XENSND_PCM_FORMAT_U24_LE_STR "u24_le" |
| 506 | #define XENSND_PCM_FORMAT_U24_BE_STR "u24_be" |
| 507 | #define XENSND_PCM_FORMAT_S32_LE_STR "s32_le" |
| 508 | #define XENSND_PCM_FORMAT_S32_BE_STR "s32_be" |
| 509 | #define XENSND_PCM_FORMAT_U32_LE_STR "u32_le" |
| 510 | #define XENSND_PCM_FORMAT_U32_BE_STR "u32_be" |
| 511 | #define XENSND_PCM_FORMAT_F32_LE_STR "float_le" |
| 512 | #define XENSND_PCM_FORMAT_F32_BE_STR "float_be" |
| 513 | #define XENSND_PCM_FORMAT_F64_LE_STR "float64_le" |
| 514 | #define XENSND_PCM_FORMAT_F64_BE_STR "float64_be" |
| 515 | #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR "iec958_subframe_le" |
| 516 | #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR "iec958_subframe_be" |
| 517 | #define XENSND_PCM_FORMAT_MU_LAW_STR "mu_law" |
| 518 | #define XENSND_PCM_FORMAT_A_LAW_STR "a_law" |
| 519 | #define XENSND_PCM_FORMAT_IMA_ADPCM_STR "ima_adpcm" |
| 520 | #define XENSND_PCM_FORMAT_MPEG_STR "mpeg" |
| 521 | #define XENSND_PCM_FORMAT_GSM_STR "gsm" |
| 522 | |
| 523 | |
| 524 | /* |
| 525 | ****************************************************************************** |
| 526 | * STATUS RETURN CODES |
| 527 | ****************************************************************************** |
| 528 | * |
| 529 | * Status return code is zero on success and -XEN_EXX on failure. |
| 530 | * |
| 531 | ****************************************************************************** |
| 532 | * Assumptions |
| 533 | ****************************************************************************** |
| 534 | * o usage of grant reference 0 as invalid grant reference: |
| 535 | * grant reference 0 is valid, but never exposed to a PV driver, |
| 536 | * because of the fact it is already in use/reserved by the PV console. |
| 537 | * o all references in this document to page sizes must be treated |
| 538 | * as pages of size XEN_PAGE_SIZE unless otherwise noted. |
| 539 | * |
| 540 | ****************************************************************************** |
| 541 | * Description of the protocol between frontend and backend driver |
| 542 | ****************************************************************************** |
| 543 | * |
| 544 | * The two halves of a Para-virtual sound driver communicate with |
| 545 | * each other using shared pages and event channels. |
| 546 | * Shared page contains a ring with request/response packets. |
| 547 | * |
| 548 | * Packets, used for input/output operations, e.g. read/write, set/get volume, |
| 549 | * etc., provide offset/length fields in order to allow asynchronous protocol |
| 550 | * operation with buffer space sharing: part of the buffer allocated at |
| 551 | * XENSND_OP_OPEN can be used for audio samples and part, for example, |
| 552 | * for volume control. |
| 553 | * |
| 554 | * All reserved fields in the structures below must be 0. |
| 555 | * |
| 556 | *---------------------------------- Requests --------------------------------- |
| 557 | * |
| 558 | * All request packets have the same length (64 octets) |
| 559 | * All request packets have common header: |
| 560 | * 0 1 2 3 octet |
| 561 | * +----------------+----------------+----------------+----------------+ |
| 562 | * | id | operation | reserved | 4 |
| 563 | * +----------------+----------------+----------------+----------------+ |
| 564 | * | reserved | 8 |
| 565 | * +----------------+----------------+----------------+----------------+ |
| 566 | * id - uint16_t, private guest value, echoed in response |
| 567 | * operation - uint8_t, operation code, XENSND_OP_??? |
| 568 | * |
| 569 | * For all packets which use offset and length: |
| 570 | * offset - uint32_t, read or write data offset within the shared buffer, |
| 571 | * passed with XENSND_OP_OPEN request, octets, |
| 572 | * [0; XENSND_OP_OPEN.buffer_sz - 1]. |
| 573 | * length - uint32_t, read or write data length, octets |
| 574 | * |
| 575 | * Request open - open a PCM stream for playback or capture: |
| 576 | * |
| 577 | * 0 1 2 3 octet |
| 578 | * +----------------+----------------+----------------+----------------+ |
| 579 | * | id | XENSND_OP_OPEN | reserved | 4 |
| 580 | * +----------------+----------------+----------------+----------------+ |
| 581 | * | reserved | 8 |
| 582 | * +----------------+----------------+----------------+----------------+ |
| 583 | * | pcm_rate | 12 |
| 584 | * +----------------+----------------+----------------+----------------+ |
| 585 | * | pcm_format | pcm_channels | reserved | 16 |
| 586 | * +----------------+----------------+----------------+----------------+ |
| 587 | * | buffer_sz | 20 |
| 588 | * +----------------+----------------+----------------+----------------+ |
| 589 | * | gref_directory | 24 |
| 590 | * +----------------+----------------+----------------+----------------+ |
| 591 | * | period_sz | 28 |
| 592 | * +----------------+----------------+----------------+----------------+ |
| 593 | * | reserved | 32 |
| 594 | * +----------------+----------------+----------------+----------------+ |
| 595 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 596 | * +----------------+----------------+----------------+----------------+ |
| 597 | * | reserved | 64 |
| 598 | * +----------------+----------------+----------------+----------------+ |
| 599 | * |
| 600 | * pcm_rate - uint32_t, stream data rate, Hz |
| 601 | * pcm_format - uint8_t, XENSND_PCM_FORMAT_XXX value |
| 602 | * pcm_channels - uint8_t, number of channels of this stream, |
| 603 | * [channels-min; channels-max] |
| 604 | * buffer_sz - uint32_t, buffer size to be allocated, octets |
| 605 | * period_sz - uint32_t, event period size, octets |
| 606 | * This is the requested value of the period at which frontend would |
| 607 | * like to receive XENSND_EVT_CUR_POS notifications from the backend when |
| 608 | * stream position advances during playback/capture. |
| 609 | * It shows how many octets are expected to be played/captured before |
| 610 | * sending such an event. |
| 611 | * If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend. |
| 612 | * |
| 613 | * gref_directory - grant_ref_t, a reference to the first shared page |
| 614 | * describing shared buffer references. At least one page exists. If shared |
| 615 | * buffer size (buffer_sz) exceeds what can be addressed by this single page, |
| 616 | * then reference to the next page must be supplied (see gref_dir_next_page |
| 617 | * below) |
| 618 | */ |
| 619 | |
| 620 | struct xensnd_open_req { |
| 621 | uint32_t pcm_rate; |
| 622 | uint8_t pcm_format; |
| 623 | uint8_t pcm_channels; |
| 624 | uint16_t reserved; |
| 625 | uint32_t buffer_sz; |
| 626 | grant_ref_t gref_directory; |
| 627 | uint32_t period_sz; |
| 628 | }; |
| 629 | |
| 630 | /* |
| 631 | * Shared page for XENSND_OP_OPEN buffer descriptor (gref_directory in the |
| 632 | * request) employs a list of pages, describing all pages of the shared data |
| 633 | * buffer: |
| 634 | * 0 1 2 3 octet |
| 635 | * +----------------+----------------+----------------+----------------+ |
| 636 | * | gref_dir_next_page | 4 |
| 637 | * +----------------+----------------+----------------+----------------+ |
| 638 | * | gref[0] | 8 |
| 639 | * +----------------+----------------+----------------+----------------+ |
| 640 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 641 | * +----------------+----------------+----------------+----------------+ |
| 642 | * | gref[i] | i*4+8 |
| 643 | * +----------------+----------------+----------------+----------------+ |
| 644 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 645 | * +----------------+----------------+----------------+----------------+ |
| 646 | * | gref[N - 1] | N*4+8 |
| 647 | * +----------------+----------------+----------------+----------------+ |
| 648 | * |
| 649 | * gref_dir_next_page - grant_ref_t, reference to the next page describing |
| 650 | * page directory. Must be 0 if there are no more pages in the list. |
| 651 | * gref[i] - grant_ref_t, reference to a shared page of the buffer |
| 652 | * allocated at XENSND_OP_OPEN |
| 653 | * |
| 654 | * Number of grant_ref_t entries in the whole page directory is not |
| 655 | * passed, but instead can be calculated as: |
| 656 | * num_grefs_total = (XENSND_OP_OPEN.buffer_sz + XEN_PAGE_SIZE - 1) / |
| 657 | * XEN_PAGE_SIZE |
| 658 | */ |
| 659 | |
| 660 | struct xensnd_page_directory { |
| 661 | grant_ref_t gref_dir_next_page; |
| 662 | grant_ref_t gref[1]; /* Variable length */ |
| 663 | }; |
| 664 | |
| 665 | /* |
| 666 | * Request close - close an opened pcm stream: |
| 667 | * 0 1 2 3 octet |
| 668 | * +----------------+----------------+----------------+----------------+ |
| 669 | * | id | XENSND_OP_CLOSE| reserved | 4 |
| 670 | * +----------------+----------------+----------------+----------------+ |
| 671 | * | reserved | 8 |
| 672 | * +----------------+----------------+----------------+----------------+ |
| 673 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 674 | * +----------------+----------------+----------------+----------------+ |
| 675 | * | reserved | 64 |
| 676 | * +----------------+----------------+----------------+----------------+ |
| 677 | * |
| 678 | * Request read/write - used for read (for capture) or write (for playback): |
| 679 | * 0 1 2 3 octet |
| 680 | * +----------------+----------------+----------------+----------------+ |
| 681 | * | id | operation | reserved | 4 |
| 682 | * +----------------+----------------+----------------+----------------+ |
| 683 | * | reserved | 8 |
| 684 | * +----------------+----------------+----------------+----------------+ |
| 685 | * | offset | 12 |
| 686 | * +----------------+----------------+----------------+----------------+ |
| 687 | * | length | 16 |
| 688 | * +----------------+----------------+----------------+----------------+ |
| 689 | * | reserved | 20 |
| 690 | * +----------------+----------------+----------------+----------------+ |
| 691 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 692 | * +----------------+----------------+----------------+----------------+ |
| 693 | * | reserved | 64 |
| 694 | * +----------------+----------------+----------------+----------------+ |
| 695 | * |
| 696 | * operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write |
| 697 | */ |
| 698 | |
| 699 | struct xensnd_rw_req { |
| 700 | uint32_t offset; |
| 701 | uint32_t length; |
| 702 | }; |
| 703 | |
| 704 | /* |
| 705 | * Request set/get volume - set/get channels' volume of the stream given: |
| 706 | * 0 1 2 3 octet |
| 707 | * +----------------+----------------+----------------+----------------+ |
| 708 | * | id | operation | reserved | 4 |
| 709 | * +----------------+----------------+----------------+----------------+ |
| 710 | * | reserved | 8 |
| 711 | * +----------------+----------------+----------------+----------------+ |
| 712 | * | offset | 12 |
| 713 | * +----------------+----------------+----------------+----------------+ |
| 714 | * | length | 16 |
| 715 | * +----------------+----------------+----------------+----------------+ |
| 716 | * | reserved | 20 |
| 717 | * +----------------+----------------+----------------+----------------+ |
| 718 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 719 | * +----------------+----------------+----------------+----------------+ |
| 720 | * | reserved | 64 |
| 721 | * +----------------+----------------+----------------+----------------+ |
| 722 | * |
| 723 | * operation - XENSND_OP_SET_VOLUME for volume set |
| 724 | * or XENSND_OP_GET_VOLUME for volume get |
| 725 | * Buffer passed with XENSND_OP_OPEN is used to exchange volume |
| 726 | * values: |
| 727 | * |
| 728 | * 0 1 2 3 octet |
| 729 | * +----------------+----------------+----------------+----------------+ |
| 730 | * | channel[0] | 4 |
| 731 | * +----------------+----------------+----------------+----------------+ |
| 732 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 733 | * +----------------+----------------+----------------+----------------+ |
| 734 | * | channel[i] | i*4 |
| 735 | * +----------------+----------------+----------------+----------------+ |
| 736 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 737 | * +----------------+----------------+----------------+----------------+ |
| 738 | * | channel[N - 1] | (N-1)*4 |
| 739 | * +----------------+----------------+----------------+----------------+ |
| 740 | * |
| 741 | * N = XENSND_OP_OPEN.pcm_channels |
| 742 | * i - uint8_t, index of a channel |
| 743 | * channel[i] - sint32_t, volume of i-th channel |
| 744 | * Volume is expressed as a signed value in steps of 0.001 dB, |
| 745 | * while 0 being 0 dB. |
| 746 | * |
| 747 | * Request mute/unmute - mute/unmute stream: |
| 748 | * 0 1 2 3 octet |
| 749 | * +----------------+----------------+----------------+----------------+ |
| 750 | * | id | operation | reserved | 4 |
| 751 | * +----------------+----------------+----------------+----------------+ |
| 752 | * | reserved | 8 |
| 753 | * +----------------+----------------+----------------+----------------+ |
| 754 | * | offset | 12 |
| 755 | * +----------------+----------------+----------------+----------------+ |
| 756 | * | length | 16 |
| 757 | * +----------------+----------------+----------------+----------------+ |
| 758 | * | reserved | 20 |
| 759 | * +----------------+----------------+----------------+----------------+ |
| 760 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 761 | * +----------------+----------------+----------------+----------------+ |
| 762 | * | reserved | 64 |
| 763 | * +----------------+----------------+----------------+----------------+ |
| 764 | * |
| 765 | * operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute |
| 766 | * Buffer passed with XENSND_OP_OPEN is used to exchange mute/unmute |
| 767 | * values: |
| 768 | * |
| 769 | * 0 octet |
| 770 | * +----------------+----------------+----------------+----------------+ |
| 771 | * | channel[0] | 4 |
| 772 | * +----------------+----------------+----------------+----------------+ |
| 773 | * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 774 | * +----------------+----------------+----------------+----------------+ |
| 775 | * | channel[i] | i*4 |
| 776 | * +----------------+----------------+----------------+----------------+ |
| 777 | * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 778 | * +----------------+----------------+----------------+----------------+ |
| 779 | * | channel[N - 1] | (N-1)*4 |
| 780 | * +----------------+----------------+----------------+----------------+ |
| 781 | * |
| 782 | * N = XENSND_OP_OPEN.pcm_channels |
| 783 | * i - uint8_t, index of a channel |
| 784 | * channel[i] - uint8_t, non-zero if i-th channel needs to be muted/unmuted |
| 785 | * |
| 786 | *------------------------------------ N.B. ----------------------------------- |
| 787 | * |
| 788 | * The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME, |
| 789 | * XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE. |
| 790 | * |
| 791 | * Request stream running state change - trigger PCM stream running state |
| 792 | * to start, stop, pause or resume: |
| 793 | * |
| 794 | * 0 1 2 3 octet |
| 795 | * +----------------+----------------+----------------+----------------+ |
| 796 | * | id | _OP_TRIGGER | reserved | 4 |
| 797 | * +----------------+----------------+----------------+----------------+ |
| 798 | * | reserved | 8 |
| 799 | * +----------------+----------------+----------------+----------------+ |
| 800 | * | type | reserved | 12 |
| 801 | * +----------------+----------------+----------------+----------------+ |
| 802 | * | reserved | 16 |
| 803 | * +----------------+----------------+----------------+----------------+ |
| 804 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 805 | * +----------------+----------------+----------------+----------------+ |
| 806 | * | reserved | 64 |
| 807 | * +----------------+----------------+----------------+----------------+ |
| 808 | * |
| 809 | * type - uint8_t, XENSND_OP_TRIGGER_XXX value |
| 810 | */ |
| 811 | |
| 812 | struct xensnd_trigger_req { |
| 813 | uint8_t type; |
| 814 | }; |
| 815 | |
| 816 | /* |
| 817 | * Request stream parameter ranges: request intervals and |
| 818 | * masks of supported ranges for stream configuration values. |
| 819 | * |
| 820 | * Sound device configuration for a particular stream is a limited subset |
| 821 | * of the multidimensional configuration available on XenStore, e.g. |
| 822 | * once the frame rate has been selected there is a limited supported range |
| 823 | * for sample rates becomes available (which might be the same set configured |
| 824 | * on XenStore or less). For example, selecting 96kHz sample rate may limit |
| 825 | * number of channels available for such configuration from 4 to 2, etc. |
| 826 | * Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration |
| 827 | * space making it possible to iteratively get the final stream configuration, |
| 828 | * used in XENSND_OP_OPEN request. |
| 829 | * |
| 830 | * See response format for this request. |
| 831 | * |
| 832 | * 0 1 2 3 octet |
| 833 | * +----------------+----------------+----------------+----------------+ |
| 834 | * | id | _HW_PARAM_QUERY| reserved | 4 |
| 835 | * +----------------+----------------+----------------+----------------+ |
| 836 | * | reserved | 8 |
| 837 | * +----------------+----------------+----------------+----------------+ |
| 838 | * | formats mask low 32-bit | 12 |
| 839 | * +----------------+----------------+----------------+----------------+ |
| 840 | * | formats mask high 32-bit | 16 |
| 841 | * +----------------+----------------+----------------+----------------+ |
| 842 | * | min rate | 20 |
| 843 | * +----------------+----------------+----------------+----------------+ |
| 844 | * | max rate | 24 |
| 845 | * +----------------+----------------+----------------+----------------+ |
| 846 | * | min channels | 28 |
| 847 | * +----------------+----------------+----------------+----------------+ |
| 848 | * | max channels | 32 |
| 849 | * +----------------+----------------+----------------+----------------+ |
| 850 | * | min buffer frames | 36 |
| 851 | * +----------------+----------------+----------------+----------------+ |
| 852 | * | max buffer frames | 40 |
| 853 | * +----------------+----------------+----------------+----------------+ |
| 854 | * | min period frames | 44 |
| 855 | * +----------------+----------------+----------------+----------------+ |
| 856 | * | max period frames | 48 |
| 857 | * +----------------+----------------+----------------+----------------+ |
| 858 | * | reserved | 52 |
| 859 | * +----------------+----------------+----------------+----------------+ |
| 860 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 861 | * +----------------+----------------+----------------+----------------+ |
| 862 | * | reserved | 64 |
| 863 | * +----------------+----------------+----------------+----------------+ |
| 864 | * |
| 865 | * formats - uint64_t, bit mask representing values of the parameter |
| 866 | * made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values |
| 867 | * |
| 868 | * For interval parameters: |
| 869 | * min - uint32_t, minimum value of the parameter |
| 870 | * max - uint32_t, maximum value of the parameter |
| 871 | * |
| 872 | * Frame is defined as a product of the number of channels by the |
| 873 | * number of octets per one sample. |
| 874 | */ |
| 875 | |
| 876 | struct xensnd_query_hw_param { |
| 877 | uint64_t formats; |
| 878 | struct { |
| 879 | uint32_t min; |
| 880 | uint32_t max; |
| 881 | } rates; |
| 882 | struct { |
| 883 | uint32_t min; |
| 884 | uint32_t max; |
| 885 | } channels; |
| 886 | struct { |
| 887 | uint32_t min; |
| 888 | uint32_t max; |
| 889 | } buffer; |
| 890 | struct { |
| 891 | uint32_t min; |
| 892 | uint32_t max; |
| 893 | } period; |
| 894 | }; |
| 895 | |
| 896 | /* |
| 897 | *---------------------------------- Responses -------------------------------- |
| 898 | * |
| 899 | * All response packets have the same length (64 octets) |
| 900 | * |
| 901 | * All response packets have common header: |
| 902 | * 0 1 2 3 octet |
| 903 | * +----------------+----------------+----------------+----------------+ |
| 904 | * | id | operation | reserved | 4 |
| 905 | * +----------------+----------------+----------------+----------------+ |
| 906 | * | status | 8 |
| 907 | * +----------------+----------------+----------------+----------------+ |
| 908 | * |
| 909 | * id - uint16_t, copied from the request |
| 910 | * operation - uint8_t, XENSND_OP_* - copied from request |
| 911 | * status - int32_t, response status, zero on success and -XEN_EXX on failure |
| 912 | * |
| 913 | * |
| 914 | * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY: |
| 915 | * 0 1 2 3 octet |
| 916 | * +----------------+----------------+----------------+----------------+ |
| 917 | * | id | operation | reserved | 4 |
| 918 | * +----------------+----------------+----------------+----------------+ |
| 919 | * | status | 8 |
| 920 | * +----------------+----------------+----------------+----------------+ |
| 921 | * | formats mask low 32-bit | 12 |
| 922 | * +----------------+----------------+----------------+----------------+ |
| 923 | * | formats mask high 32-bit | 16 |
| 924 | * +----------------+----------------+----------------+----------------+ |
| 925 | * | min rate | 20 |
| 926 | * +----------------+----------------+----------------+----------------+ |
| 927 | * | max rate | 24 |
| 928 | * +----------------+----------------+----------------+----------------+ |
| 929 | * | min channels | 28 |
| 930 | * +----------------+----------------+----------------+----------------+ |
| 931 | * | max channels | 32 |
| 932 | * +----------------+----------------+----------------+----------------+ |
| 933 | * | min buffer frames | 36 |
| 934 | * +----------------+----------------+----------------+----------------+ |
| 935 | * | max buffer frames | 40 |
| 936 | * +----------------+----------------+----------------+----------------+ |
| 937 | * | min period frames | 44 |
| 938 | * +----------------+----------------+----------------+----------------+ |
| 939 | * | max period frames | 48 |
| 940 | * +----------------+----------------+----------------+----------------+ |
| 941 | * | reserved | 52 |
| 942 | * +----------------+----------------+----------------+----------------+ |
| 943 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 944 | * +----------------+----------------+----------------+----------------+ |
| 945 | * | reserved | 64 |
| 946 | * +----------------+----------------+----------------+----------------+ |
| 947 | * |
| 948 | * Meaning of the values in this response is the same as for |
| 949 | * XENSND_OP_HW_PARAM_QUERY request. |
| 950 | */ |
| 951 | |
| 952 | /* |
| 953 | *----------------------------------- Events ---------------------------------- |
| 954 | * |
| 955 | * Events are sent via shared page allocated by the front and propagated by |
| 956 | * evt-event-channel/evt-ring-ref XenStore entries |
| 957 | * All event packets have the same length (64 octets) |
| 958 | * All event packets have common header: |
| 959 | * 0 1 2 3 octet |
| 960 | * +----------------+----------------+----------------+----------------+ |
| 961 | * | id | type | reserved | 4 |
| 962 | * +----------------+----------------+----------------+----------------+ |
| 963 | * | reserved | 8 |
| 964 | * +----------------+----------------+----------------+----------------+ |
| 965 | * |
| 966 | * id - uint16_t, event id, may be used by front |
| 967 | * type - uint8_t, type of the event |
| 968 | * |
| 969 | * |
| 970 | * Current stream position - event from back to front when stream's |
| 971 | * playback/capture position has advanced: |
| 972 | * 0 1 2 3 octet |
| 973 | * +----------------+----------------+----------------+----------------+ |
| 974 | * | id | _EVT_CUR_POS | reserved | 4 |
| 975 | * +----------------+----------------+----------------+----------------+ |
| 976 | * | reserved | 8 |
| 977 | * +----------------+----------------+----------------+----------------+ |
| 978 | * | position low 32-bit | 12 |
| 979 | * +----------------+----------------+----------------+----------------+ |
| 980 | * | position high 32-bit | 16 |
| 981 | * +----------------+----------------+----------------+----------------+ |
| 982 | * | reserved | 20 |
| 983 | * +----------------+----------------+----------------+----------------+ |
| 984 | * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| |
| 985 | * +----------------+----------------+----------------+----------------+ |
| 986 | * | reserved | 64 |
| 987 | * +----------------+----------------+----------------+----------------+ |
| 988 | * |
| 989 | * position - current value of stream's playback/capture position, octets |
| 990 | * |
| 991 | */ |
| 992 | |
| 993 | struct xensnd_cur_pos_evt { |
| 994 | uint64_t position; |
| 995 | }; |
| 996 | |
| 997 | struct xensnd_req { |
| 998 | uint16_t id; |
| 999 | uint8_t operation; |
| 1000 | uint8_t reserved[5]; |
| 1001 | union { |
| 1002 | struct xensnd_open_req open; |
| 1003 | struct xensnd_rw_req rw; |
| 1004 | struct xensnd_trigger_req trigger; |
| 1005 | struct xensnd_query_hw_param hw_param; |
| 1006 | uint8_t reserved[56]; |
| 1007 | } op; |
| 1008 | }; |
| 1009 | |
| 1010 | struct xensnd_resp { |
| 1011 | uint16_t id; |
| 1012 | uint8_t operation; |
| 1013 | uint8_t reserved; |
| 1014 | int32_t status; |
| 1015 | union { |
| 1016 | struct xensnd_query_hw_param hw_param; |
| 1017 | uint8_t reserved1[56]; |
| 1018 | } resp; |
| 1019 | }; |
| 1020 | |
| 1021 | struct xensnd_evt { |
| 1022 | uint16_t id; |
| 1023 | uint8_t type; |
| 1024 | uint8_t reserved[5]; |
| 1025 | union { |
| 1026 | struct xensnd_cur_pos_evt cur_pos; |
| 1027 | uint8_t reserved[56]; |
| 1028 | } op; |
| 1029 | }; |
| 1030 | |
| 1031 | DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp); |
| 1032 | |
| 1033 | /* |
| 1034 | ****************************************************************************** |
| 1035 | * Back to front events delivery |
| 1036 | ****************************************************************************** |
| 1037 | * In order to deliver asynchronous events from back to front a shared page is |
| 1038 | * allocated by front and its granted reference propagated to back via |
| 1039 | * XenStore entries (evt-ring-ref/evt-event-channel). |
| 1040 | * This page has a common header used by both front and back to synchronize |
| 1041 | * access and control event's ring buffer, while back being a producer of the |
| 1042 | * events and front being a consumer. The rest of the page after the header |
| 1043 | * is used for event packets. |
| 1044 | * |
| 1045 | * Upon reception of an event(s) front may confirm its reception |
| 1046 | * for either each event, group of events or none. |
| 1047 | */ |
| 1048 | |
| 1049 | struct xensnd_event_page { |
| 1050 | uint32_t in_cons; |
| 1051 | uint32_t in_prod; |
| 1052 | uint8_t reserved[56]; |
| 1053 | }; |
| 1054 | |
| 1055 | #define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE |
| 1056 | #define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page)) |
| 1057 | #define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS) |
| 1058 | #define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt)) |
| 1059 | #define XENSND_IN_RING(page) \ |
| 1060 | ((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS)) |
| 1061 | #define XENSND_IN_RING_REF(page, idx) \ |
| 1062 | (XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN]) |
| 1063 | |
| 1064 | #endif /* __XEN_PUBLIC_IO_SNDIF_H__ */ |
| 1065 |
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