1 /******************************************************************************
4 * Unified sound-device I/O interface for Xen guest OSes.
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
24 * Copyright (C) 2013-2015 GlobalLogic Inc.
25 * Copyright (C) 2016-2017 EPAM Systems Inc.
27 * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
28 * Oleksandr Grytsov <oleksandr_grytsov@epam.com>
29 * Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
30 * Iurii Konovalenko <iurii.konovalenko@globallogic.com>
33 #ifndef __XEN_PUBLIC_IO_SNDIF_H__
34 #define __XEN_PUBLIC_IO_SNDIF_H__
37 #include "../grant_table.h"
40 ******************************************************************************
42 ******************************************************************************
44 #define XENSND_PROTOCOL_VERSION 2
47 ******************************************************************************
48 * Feature and Parameter Negotiation
49 ******************************************************************************
51 * Front->back notifications: when enqueuing a new request, sending a
52 * notification can be made conditional on xensnd_req (i.e., the generic
53 * hold-off mechanism provided by the ring macros). Backends must set
54 * xensnd_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()).
56 * Back->front notifications: when enqueuing a new response, sending a
57 * notification can be made conditional on xensnd_resp (i.e., the generic
58 * hold-off mechanism provided by the ring macros). Frontends must set
59 * xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
61 * The two halves of a para-virtual sound card driver utilize nodes within
62 * XenStore to communicate capabilities and to negotiate operating parameters.
63 * This section enumerates these nodes which reside in the respective front and
64 * backend portions of XenStore, following the XenBus convention.
66 * All data in XenStore is stored as strings. Nodes specifying numeric
67 * values are encoded in decimal. Integer value ranges listed below are
68 * expressed as fixed sized integer types capable of storing the conversion
69 * of a properly formated node string, without loss of information.
71 ******************************************************************************
72 * Example configuration
73 ******************************************************************************
75 * Note: depending on the use-case backend can expose more sound cards and
76 * PCM devices/streams than the underlying HW physically has by employing
77 * SW mixers, configuring virtual sound streams, channels etc.
79 * This is an example of backend and frontend configuration:
81 *--------------------------------- Backend -----------------------------------
83 * /local/domain/0/backend/vsnd/1/0/frontend-id = "1"
84 * /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0"
85 * /local/domain/0/backend/vsnd/1/0/state = "4"
86 * /local/domain/0/backend/vsnd/1/0/versions = "1,2"
88 *--------------------------------- Frontend ----------------------------------
90 * /local/domain/1/device/vsnd/0/backend-id = "0"
91 * /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0"
92 * /local/domain/1/device/vsnd/0/state = "4"
93 * /local/domain/1/device/vsnd/0/version = "1"
95 *----------------------------- Card configuration ----------------------------
97 * /local/domain/1/device/vsnd/0/short-name = "Card short name"
98 * /local/domain/1/device/vsnd/0/long-name = "Card long name"
99 * /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000"
100 * /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be"
101 * /local/domain/1/device/vsnd/0/buffer-size = "262144"
103 *------------------------------- PCM device 0 --------------------------------
105 * /local/domain/1/device/vsnd/0/0/name = "General analog"
106 * /local/domain/1/device/vsnd/0/0/channels-max = "5"
108 *----------------------------- Stream 0, playback ----------------------------
110 * /local/domain/1/device/vsnd/0/0/0/type = "p"
111 * /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8"
112 * /local/domain/1/device/vsnd/0/0/0/unique-id = "0"
114 * /local/domain/1/device/vsnd/0/0/0/ring-ref = "386"
115 * /local/domain/1/device/vsnd/0/0/0/event-channel = "15"
116 * /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386"
117 * /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215"
119 *------------------------------ Stream 1, capture ----------------------------
121 * /local/domain/1/device/vsnd/0/0/1/type = "c"
122 * /local/domain/1/device/vsnd/0/0/1/channels-max = "2"
123 * /local/domain/1/device/vsnd/0/0/1/unique-id = "1"
125 * /local/domain/1/device/vsnd/0/0/1/ring-ref = "384"
126 * /local/domain/1/device/vsnd/0/0/1/event-channel = "13"
127 * /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384"
128 * /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213"
130 *------------------------------- PCM device 1 --------------------------------
132 * /local/domain/1/device/vsnd/0/1/name = "HDMI-0"
133 * /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100"
135 *------------------------------ Stream 0, capture ----------------------------
137 * /local/domain/1/device/vsnd/0/1/0/type = "c"
138 * /local/domain/1/device/vsnd/0/1/0/unique-id = "2"
140 * /local/domain/1/device/vsnd/0/1/0/ring-ref = "387"
141 * /local/domain/1/device/vsnd/0/1/0/event-channel = "151"
142 * /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387"
143 * /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351"
145 *------------------------------- PCM device 2 --------------------------------
147 * /local/domain/1/device/vsnd/0/2/name = "SPDIF"
149 *----------------------------- Stream 0, playback ----------------------------
151 * /local/domain/1/device/vsnd/0/2/0/type = "p"
152 * /local/domain/1/device/vsnd/0/2/0/unique-id = "3"
154 * /local/domain/1/device/vsnd/0/2/0/ring-ref = "389"
155 * /local/domain/1/device/vsnd/0/2/0/event-channel = "152"
156 * /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389"
157 * /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452"
159 ******************************************************************************
160 * Backend XenBus Nodes
161 ******************************************************************************
163 *----------------------------- Protocol version ------------------------------
168 * List of XENSND_LIST_SEPARATOR separated protocol versions supported
169 * by the backend. For example "1,2,3".
171 ******************************************************************************
172 * Frontend XenBus Nodes
173 ******************************************************************************
175 *-------------------------------- Addressing ---------------------------------
190 * Zero based contigous index of the PCM device.
195 * Zero based contigous index of the stream of the PCM device.
197 * The following pattern is used for addressing:
198 * /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/...
200 *----------------------------- Protocol version ------------------------------
205 * Protocol version, chosen among the ones supported by the backend.
207 *------------------------------- PCM settings --------------------------------
209 * Every virtualized sound frontend has a set of PCM devices and streams, each
210 * could be individually configured. Part of the PCM configuration can be
211 * defined at higher level of the hierarchy and be fully or partially re-used
212 * by the underlying layers. These configuration values are:
213 * o number of channels (min/max)
214 * o supported sample rates
215 * o supported sample formats.
216 * E.g. one can define these values for the whole card, device or stream.
217 * Every underlying layer in turn can re-define some or all of them to better
218 * fit its needs. For example, card may define number of channels to be
219 * in [1; 8] range, and some particular stream may be limited to [1; 2] only.
220 * The rule is that the underlying layer must be a subset of the upper layer
226 * The minimum amount of channels that is supported, [1; channels-max].
227 * Optional, if not set or omitted a value of 1 is used.
232 * The maximum amount of channels that is supported.
233 * Must be at least <channels-min>.
236 * Values: <list of uint32_t>
238 * List of supported sample rates separated by XENSND_LIST_SEPARATOR.
239 * Sample rates are expressed as a list of decimal values w/o any
240 * ordering requirement.
243 * Values: <list of XENSND_PCM_FORMAT_XXX_STR>
245 * List of supported sample formats separated by XENSND_LIST_SEPARATOR.
246 * Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length.
251 * The maximum size in octets of the buffer to allocate per stream.
253 *----------------------- Virtual sound card settings -------------------------
257 * Short name of the virtual sound card. Optional.
262 * Long name of the virtual sound card. Optional.
264 *----------------------------- Device settings -------------------------------
268 * Name of the sound device within the virtual sound card. Optional.
270 *----------------------------- Stream settings -------------------------------
275 * Stream type: "p" - playback stream, "c" - capture stream
277 * If both capture and playback are needed then two streams need to be
278 * defined under the same device.
283 * After stream initialization it is assigned a unique ID (within the front
284 * driver), so every stream of the frontend can be identified by the
285 * backend by this ID. This is not equal to stream-idx as the later is
286 * zero based within the device, but this index is contigous within the
289 *-------------------- Stream Request Transport Parameters --------------------
294 * The identifier of the Xen event channel used to signal activity
295 * in the ring buffer.
300 * The Xen grant reference granting permission for the backend to map
301 * a sole page in a single page sized ring buffer.
303 *--------------------- Stream Event Transport Parameters ---------------------
305 * This communication path is used to deliver asynchronous events from backend
306 * to frontend, set up per stream.
311 * The identifier of the Xen event channel used to signal activity
312 * in the ring buffer.
317 * The Xen grant reference granting permission for the backend to map
318 * a sole page in a single page sized ring buffer.
320 ******************************************************************************
322 ******************************************************************************
324 * Tool stack creates front and back state nodes with initial state
325 * XenbusStateInitialising.
326 * Tool stack creates and sets up frontend sound configuration nodes per domain.
329 * ================================= =====================================
330 * XenbusStateInitialising XenbusStateInitialising
331 * o Query backend device identification
333 * o Open and validate backend device.
337 * XenbusStateInitWait
339 * o Query frontend configuration
340 * o Allocate and initialize
341 * event channels per configured
342 * playback/capture stream.
343 * o Publish transport parameters
344 * that will be in effect during
349 * XenbusStateInitialised
351 * o Query frontend transport parameters.
352 * o Connect to the event channels.
356 * XenbusStateConnected
358 * o Create and initialize OS
359 * virtual sound device instances
360 * as per configuration.
364 * XenbusStateConnected
369 * o Remove virtual sound device
370 * o Remove event channels
376 *------------------------------- Recovery flow -------------------------------
378 * In case of frontend unrecoverable errors backend handles that as
379 * if frontend goes into the XenbusStateClosed state.
381 * In case of backend unrecoverable errors frontend tries removing
382 * the virtualized device. If this is possible at the moment of error,
383 * then frontend goes into the XenbusStateInitialising state and is ready for
384 * new connection with backend. If the virtualized device is still in use and
385 * cannot be removed, then frontend goes into the XenbusStateReconfiguring state
386 * until either the virtualized device removed or backend initiates a new
387 * connection. On the virtualized device removal frontend goes into the
388 * XenbusStateInitialising state.
390 * Note on XenbusStateReconfiguring state of the frontend: if backend has
391 * unrecoverable errors then frontend cannot send requests to the backend
392 * and thus cannot provide functionality of the virtualized device anymore.
393 * After backend is back to normal the virtualized device may still hold some
394 * state: configuration in use, allocated buffers, client application state etc.
395 * So, in most cases, this will require frontend to implement complex recovery
396 * reconnect logic. Instead, by going into XenbusStateReconfiguring state,
397 * frontend will make sure no new clients of the virtualized device are
398 * accepted, allow existing client(s) to exit gracefully by signaling error
400 * Once all the clients are gone frontend can reinitialize the virtualized
401 * device and get into XenbusStateInitialising state again signaling the
402 * backend that a new connection can be made.
404 * There are multiple conditions possible under which frontend will go from
405 * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS
406 * specific. For example:
407 * 1. The underlying OS framework may provide callbacks to signal that the last
408 * client of the virtualized device has gone and the device can be removed
409 * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue)
410 * to periodically check if this is the right time to re-try removal of
411 * the virtualized device.
412 * 3. By any other means.
414 ******************************************************************************
416 ******************************************************************************
418 * XENSND_PCM_FORMAT_<format>[_<endian>]
420 * format: <S/U/F><bits> or <name>
421 * S - signed, U - unsigned, F - float
422 * bits - 8, 16, 24, 32
423 * name - MU_LAW, GSM, etc.
425 * endian: <LE/BE>, may be absent
426 * LE - Little endian, BE - Big endian
428 #define XENSND_PCM_FORMAT_S8 0
429 #define XENSND_PCM_FORMAT_U8 1
430 #define XENSND_PCM_FORMAT_S16_LE 2
431 #define XENSND_PCM_FORMAT_S16_BE 3
432 #define XENSND_PCM_FORMAT_U16_LE 4
433 #define XENSND_PCM_FORMAT_U16_BE 5
434 #define XENSND_PCM_FORMAT_S24_LE 6
435 #define XENSND_PCM_FORMAT_S24_BE 7
436 #define XENSND_PCM_FORMAT_U24_LE 8
437 #define XENSND_PCM_FORMAT_U24_BE 9
438 #define XENSND_PCM_FORMAT_S32_LE 10
439 #define XENSND_PCM_FORMAT_S32_BE 11
440 #define XENSND_PCM_FORMAT_U32_LE 12
441 #define XENSND_PCM_FORMAT_U32_BE 13
442 #define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */
443 #define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */
444 #define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */
445 #define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */
446 #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18
447 #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19
448 #define XENSND_PCM_FORMAT_MU_LAW 20
449 #define XENSND_PCM_FORMAT_A_LAW 21
450 #define XENSND_PCM_FORMAT_IMA_ADPCM 22
451 #define XENSND_PCM_FORMAT_MPEG 23
452 #define XENSND_PCM_FORMAT_GSM 24
455 ******************************************************************************
457 ******************************************************************************
459 #define XENSND_OP_OPEN 0
460 #define XENSND_OP_CLOSE 1
461 #define XENSND_OP_READ 2
462 #define XENSND_OP_WRITE 3
463 #define XENSND_OP_SET_VOLUME 4
464 #define XENSND_OP_GET_VOLUME 5
465 #define XENSND_OP_MUTE 6
466 #define XENSND_OP_UNMUTE 7
467 #define XENSND_OP_TRIGGER 8
468 #define XENSND_OP_HW_PARAM_QUERY 9
470 #define XENSND_OP_TRIGGER_START 0
471 #define XENSND_OP_TRIGGER_PAUSE 1
472 #define XENSND_OP_TRIGGER_STOP 2
473 #define XENSND_OP_TRIGGER_RESUME 3
476 ******************************************************************************
478 ******************************************************************************
480 #define XENSND_EVT_CUR_POS 0
483 ******************************************************************************
484 * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS
485 ******************************************************************************
487 #define XENSND_DRIVER_NAME "vsnd"
489 #define XENSND_LIST_SEPARATOR ","
491 #define XENSND_FIELD_BE_VERSIONS "versions"
492 #define XENSND_FIELD_FE_VERSION "version"
493 #define XENSND_FIELD_VCARD_SHORT_NAME "short-name"
494 #define XENSND_FIELD_VCARD_LONG_NAME "long-name"
495 #define XENSND_FIELD_RING_REF "ring-ref"
496 #define XENSND_FIELD_EVT_CHNL "event-channel"
497 #define XENSND_FIELD_EVT_RING_REF "evt-ring-ref"
498 #define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel"
499 #define XENSND_FIELD_DEVICE_NAME "name"
500 #define XENSND_FIELD_TYPE "type"
501 #define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id"
502 #define XENSND_FIELD_CHANNELS_MIN "channels-min"
503 #define XENSND_FIELD_CHANNELS_MAX "channels-max"
504 #define XENSND_FIELD_SAMPLE_RATES "sample-rates"
505 #define XENSND_FIELD_SAMPLE_FORMATS "sample-formats"
506 #define XENSND_FIELD_BUFFER_SIZE "buffer-size"
508 /* Stream type field values. */
509 #define XENSND_STREAM_TYPE_PLAYBACK "p"
510 #define XENSND_STREAM_TYPE_CAPTURE "c"
511 /* Sample rate max string length */
512 #define XENSND_SAMPLE_RATE_MAX_LEN 11
513 /* Sample format field values */
514 #define XENSND_SAMPLE_FORMAT_MAX_LEN 24
516 #define XENSND_PCM_FORMAT_S8_STR "s8"
517 #define XENSND_PCM_FORMAT_U8_STR "u8"
518 #define XENSND_PCM_FORMAT_S16_LE_STR "s16_le"
519 #define XENSND_PCM_FORMAT_S16_BE_STR "s16_be"
520 #define XENSND_PCM_FORMAT_U16_LE_STR "u16_le"
521 #define XENSND_PCM_FORMAT_U16_BE_STR "u16_be"
522 #define XENSND_PCM_FORMAT_S24_LE_STR "s24_le"
523 #define XENSND_PCM_FORMAT_S24_BE_STR "s24_be"
524 #define XENSND_PCM_FORMAT_U24_LE_STR "u24_le"
525 #define XENSND_PCM_FORMAT_U24_BE_STR "u24_be"
526 #define XENSND_PCM_FORMAT_S32_LE_STR "s32_le"
527 #define XENSND_PCM_FORMAT_S32_BE_STR "s32_be"
528 #define XENSND_PCM_FORMAT_U32_LE_STR "u32_le"
529 #define XENSND_PCM_FORMAT_U32_BE_STR "u32_be"
530 #define XENSND_PCM_FORMAT_F32_LE_STR "float_le"
531 #define XENSND_PCM_FORMAT_F32_BE_STR "float_be"
532 #define XENSND_PCM_FORMAT_F64_LE_STR "float64_le"
533 #define XENSND_PCM_FORMAT_F64_BE_STR "float64_be"
534 #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR "iec958_subframe_le"
535 #define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR "iec958_subframe_be"
536 #define XENSND_PCM_FORMAT_MU_LAW_STR "mu_law"
537 #define XENSND_PCM_FORMAT_A_LAW_STR "a_law"
538 #define XENSND_PCM_FORMAT_IMA_ADPCM_STR "ima_adpcm"
539 #define XENSND_PCM_FORMAT_MPEG_STR "mpeg"
540 #define XENSND_PCM_FORMAT_GSM_STR "gsm"
544 ******************************************************************************
545 * STATUS RETURN CODES
546 ******************************************************************************
548 * Status return code is zero on success and -XEN_EXX on failure.
550 ******************************************************************************
552 ******************************************************************************
553 * o usage of grant reference 0 as invalid grant reference:
554 * grant reference 0 is valid, but never exposed to a PV driver,
555 * because of the fact it is already in use/reserved by the PV console.
556 * o all references in this document to page sizes must be treated
557 * as pages of size XEN_PAGE_SIZE unless otherwise noted.
559 ******************************************************************************
560 * Description of the protocol between frontend and backend driver
561 ******************************************************************************
563 * The two halves of a Para-virtual sound driver communicate with
564 * each other using shared pages and event channels.
565 * Shared page contains a ring with request/response packets.
567 * Packets, used for input/output operations, e.g. read/write, set/get volume,
568 * etc., provide offset/length fields in order to allow asynchronous protocol
569 * operation with buffer space sharing: part of the buffer allocated at
570 * XENSND_OP_OPEN can be used for audio samples and part, for example,
571 * for volume control.
573 * All reserved fields in the structures below must be 0.
575 *---------------------------------- Requests ---------------------------------
577 * All request packets have the same length (64 octets)
578 * All request packets have common header:
580 * +----------------+----------------+----------------+----------------+
581 * | id | operation | reserved | 4
582 * +----------------+----------------+----------------+----------------+
584 * +----------------+----------------+----------------+----------------+
585 * id - uint16_t, private guest value, echoed in response
586 * operation - uint8_t, operation code, XENSND_OP_???
588 * For all packets which use offset and length:
589 * offset - uint32_t, read or write data offset within the shared buffer,
590 * passed with XENSND_OP_OPEN request, octets,
591 * [0; XENSND_OP_OPEN.buffer_sz - 1].
592 * length - uint32_t, read or write data length, octets
594 * Request open - open a PCM stream for playback or capture:
597 * +----------------+----------------+----------------+----------------+
598 * | id | XENSND_OP_OPEN | reserved | 4
599 * +----------------+----------------+----------------+----------------+
601 * +----------------+----------------+----------------+----------------+
603 * +----------------+----------------+----------------+----------------+
604 * | pcm_format | pcm_channels | reserved | 16
605 * +----------------+----------------+----------------+----------------+
607 * +----------------+----------------+----------------+----------------+
608 * | gref_directory | 24
609 * +----------------+----------------+----------------+----------------+
611 * +----------------+----------------+----------------+----------------+
613 * +----------------+----------------+----------------+----------------+
614 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
615 * +----------------+----------------+----------------+----------------+
617 * +----------------+----------------+----------------+----------------+
619 * pcm_rate - uint32_t, stream data rate, Hz
620 * pcm_format - uint8_t, XENSND_PCM_FORMAT_XXX value
621 * pcm_channels - uint8_t, number of channels of this stream,
622 * [channels-min; channels-max]
623 * buffer_sz - uint32_t, buffer size to be allocated, octets
624 * period_sz - uint32_t, event period size, octets
625 * This is the requested value of the period at which frontend would
626 * like to receive XENSND_EVT_CUR_POS notifications from the backend when
627 * stream position advances during playback/capture.
628 * It shows how many octets are expected to be played/captured before
629 * sending such an event.
630 * If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend.
632 * gref_directory - grant_ref_t, a reference to the first shared page
633 * describing shared buffer references. At least one page exists. If shared
634 * buffer size (buffer_sz) exceeds what can be addressed by this single page,
635 * then reference to the next page must be supplied (see gref_dir_next_page
639 struct xensnd_open_req {
642 uint8_t pcm_channels;
645 grant_ref_t gref_directory;
650 * Shared page for XENSND_OP_OPEN buffer descriptor (gref_directory in the
651 * request) employs a list of pages, describing all pages of the shared data
654 * +----------------+----------------+----------------+----------------+
655 * | gref_dir_next_page | 4
656 * +----------------+----------------+----------------+----------------+
658 * +----------------+----------------+----------------+----------------+
659 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
660 * +----------------+----------------+----------------+----------------+
662 * +----------------+----------------+----------------+----------------+
663 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
664 * +----------------+----------------+----------------+----------------+
665 * | gref[N - 1] | N*4+8
666 * +----------------+----------------+----------------+----------------+
668 * gref_dir_next_page - grant_ref_t, reference to the next page describing
669 * page directory. Must be 0 if there are no more pages in the list.
670 * gref[i] - grant_ref_t, reference to a shared page of the buffer
671 * allocated at XENSND_OP_OPEN
673 * Number of grant_ref_t entries in the whole page directory is not
674 * passed, but instead can be calculated as:
675 * num_grefs_total = (XENSND_OP_OPEN.buffer_sz + XEN_PAGE_SIZE - 1) /
679 struct xensnd_page_directory {
680 grant_ref_t gref_dir_next_page;
681 grant_ref_t gref[1]; /* Variable length */
685 * Request close - close an opened pcm stream:
687 * +----------------+----------------+----------------+----------------+
688 * | id | XENSND_OP_CLOSE| reserved | 4
689 * +----------------+----------------+----------------+----------------+
691 * +----------------+----------------+----------------+----------------+
692 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
693 * +----------------+----------------+----------------+----------------+
695 * +----------------+----------------+----------------+----------------+
697 * Request read/write - used for read (for capture) or write (for playback):
699 * +----------------+----------------+----------------+----------------+
700 * | id | operation | reserved | 4
701 * +----------------+----------------+----------------+----------------+
703 * +----------------+----------------+----------------+----------------+
705 * +----------------+----------------+----------------+----------------+
707 * +----------------+----------------+----------------+----------------+
709 * +----------------+----------------+----------------+----------------+
710 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
711 * +----------------+----------------+----------------+----------------+
713 * +----------------+----------------+----------------+----------------+
715 * operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write
718 struct xensnd_rw_req {
724 * Request set/get volume - set/get channels' volume of the stream given:
726 * +----------------+----------------+----------------+----------------+
727 * | id | operation | reserved | 4
728 * +----------------+----------------+----------------+----------------+
730 * +----------------+----------------+----------------+----------------+
732 * +----------------+----------------+----------------+----------------+
734 * +----------------+----------------+----------------+----------------+
736 * +----------------+----------------+----------------+----------------+
737 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
738 * +----------------+----------------+----------------+----------------+
740 * +----------------+----------------+----------------+----------------+
742 * operation - XENSND_OP_SET_VOLUME for volume set
743 * or XENSND_OP_GET_VOLUME for volume get
744 * Buffer passed with XENSND_OP_OPEN is used to exchange volume
748 * +----------------+----------------+----------------+----------------+
750 * +----------------+----------------+----------------+----------------+
751 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
752 * +----------------+----------------+----------------+----------------+
754 * +----------------+----------------+----------------+----------------+
755 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
756 * +----------------+----------------+----------------+----------------+
757 * | channel[N - 1] | (N-1)*4
758 * +----------------+----------------+----------------+----------------+
760 * N = XENSND_OP_OPEN.pcm_channels
761 * i - uint8_t, index of a channel
762 * channel[i] - sint32_t, volume of i-th channel
763 * Volume is expressed as a signed value in steps of 0.001 dB,
764 * while 0 being 0 dB.
766 * Request mute/unmute - mute/unmute stream:
768 * +----------------+----------------+----------------+----------------+
769 * | id | operation | reserved | 4
770 * +----------------+----------------+----------------+----------------+
772 * +----------------+----------------+----------------+----------------+
774 * +----------------+----------------+----------------+----------------+
776 * +----------------+----------------+----------------+----------------+
778 * +----------------+----------------+----------------+----------------+
779 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
780 * +----------------+----------------+----------------+----------------+
782 * +----------------+----------------+----------------+----------------+
784 * operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute
785 * Buffer passed with XENSND_OP_OPEN is used to exchange mute/unmute
789 * +----------------+----------------+----------------+----------------+
791 * +----------------+----------------+----------------+----------------+
792 * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
793 * +----------------+----------------+----------------+----------------+
795 * +----------------+----------------+----------------+----------------+
796 * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
797 * +----------------+----------------+----------------+----------------+
798 * | channel[N - 1] | (N-1)*4
799 * +----------------+----------------+----------------+----------------+
801 * N = XENSND_OP_OPEN.pcm_channels
802 * i - uint8_t, index of a channel
803 * channel[i] - uint8_t, non-zero if i-th channel needs to be muted/unmuted
805 *------------------------------------ N.B. -----------------------------------
807 * The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME,
808 * XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE.
810 * Request stream running state change - trigger PCM stream running state
811 * to start, stop, pause or resume:
814 * +----------------+----------------+----------------+----------------+
815 * | id | _OP_TRIGGER | reserved | 4
816 * +----------------+----------------+----------------+----------------+
818 * +----------------+----------------+----------------+----------------+
819 * | type | reserved | 12
820 * +----------------+----------------+----------------+----------------+
822 * +----------------+----------------+----------------+----------------+
823 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
824 * +----------------+----------------+----------------+----------------+
826 * +----------------+----------------+----------------+----------------+
828 * type - uint8_t, XENSND_OP_TRIGGER_XXX value
831 struct xensnd_trigger_req {
836 * Request stream parameter ranges: request intervals and
837 * masks of supported ranges for stream configuration values.
839 * Sound device configuration for a particular stream is a limited subset
840 * of the multidimensional configuration available on XenStore, e.g.
841 * once the frame rate has been selected there is a limited supported range
842 * for sample rates becomes available (which might be the same set configured
843 * on XenStore or less). For example, selecting 96kHz sample rate may limit
844 * number of channels available for such configuration from 4 to 2, etc.
845 * Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration
846 * space making it possible to iteratively get the final stream configuration,
847 * used in XENSND_OP_OPEN request.
849 * See response format for this request.
852 * +----------------+----------------+----------------+----------------+
853 * | id | _HW_PARAM_QUERY| reserved | 4
854 * +----------------+----------------+----------------+----------------+
856 * +----------------+----------------+----------------+----------------+
857 * | formats mask low 32-bit | 12
858 * +----------------+----------------+----------------+----------------+
859 * | formats mask high 32-bit | 16
860 * +----------------+----------------+----------------+----------------+
862 * +----------------+----------------+----------------+----------------+
864 * +----------------+----------------+----------------+----------------+
865 * | min channels | 28
866 * +----------------+----------------+----------------+----------------+
867 * | max channels | 32
868 * +----------------+----------------+----------------+----------------+
869 * | min buffer frames | 36
870 * +----------------+----------------+----------------+----------------+
871 * | max buffer frames | 40
872 * +----------------+----------------+----------------+----------------+
873 * | min period frames | 44
874 * +----------------+----------------+----------------+----------------+
875 * | max period frames | 48
876 * +----------------+----------------+----------------+----------------+
878 * +----------------+----------------+----------------+----------------+
879 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
880 * +----------------+----------------+----------------+----------------+
882 * +----------------+----------------+----------------+----------------+
884 * formats - uint64_t, bit mask representing values of the parameter
885 * made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values
887 * For interval parameters:
888 * min - uint32_t, minimum value of the parameter
889 * max - uint32_t, maximum value of the parameter
891 * Frame is defined as a product of the number of channels by the
892 * number of octets per one sample.
895 struct xensnd_query_hw_param {
916 *---------------------------------- Responses --------------------------------
918 * All response packets have the same length (64 octets)
920 * All response packets have common header:
922 * +----------------+----------------+----------------+----------------+
923 * | id | operation | reserved | 4
924 * +----------------+----------------+----------------+----------------+
926 * +----------------+----------------+----------------+----------------+
928 * id - uint16_t, copied from the request
929 * operation - uint8_t, XENSND_OP_* - copied from request
930 * status - int32_t, response status, zero on success and -XEN_EXX on failure
933 * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:
935 * +----------------+----------------+----------------+----------------+
936 * | id | operation | reserved | 4
937 * +----------------+----------------+----------------+----------------+
939 * +----------------+----------------+----------------+----------------+
940 * | formats mask low 32-bit | 12
941 * +----------------+----------------+----------------+----------------+
942 * | formats mask high 32-bit | 16
943 * +----------------+----------------+----------------+----------------+
945 * +----------------+----------------+----------------+----------------+
947 * +----------------+----------------+----------------+----------------+
948 * | min channels | 28
949 * +----------------+----------------+----------------+----------------+
950 * | max channels | 32
951 * +----------------+----------------+----------------+----------------+
952 * | min buffer frames | 36
953 * +----------------+----------------+----------------+----------------+
954 * | max buffer frames | 40
955 * +----------------+----------------+----------------+----------------+
956 * | min period frames | 44
957 * +----------------+----------------+----------------+----------------+
958 * | max period frames | 48
959 * +----------------+----------------+----------------+----------------+
961 * +----------------+----------------+----------------+----------------+
962 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
963 * +----------------+----------------+----------------+----------------+
965 * +----------------+----------------+----------------+----------------+
967 * Meaning of the values in this response is the same as for
968 * XENSND_OP_HW_PARAM_QUERY request.
972 *----------------------------------- Events ----------------------------------
974 * Events are sent via shared page allocated by the front and propagated by
975 * evt-event-channel/evt-ring-ref XenStore entries
976 * All event packets have the same length (64 octets)
977 * All event packets have common header:
979 * +----------------+----------------+----------------+----------------+
980 * | id | type | reserved | 4
981 * +----------------+----------------+----------------+----------------+
983 * +----------------+----------------+----------------+----------------+
985 * id - uint16_t, event id, may be used by front
986 * type - uint8_t, type of the event
989 * Current stream position - event from back to front when stream's
990 * playback/capture position has advanced:
992 * +----------------+----------------+----------------+----------------+
993 * | id | _EVT_CUR_POS | reserved | 4
994 * +----------------+----------------+----------------+----------------+
996 * +----------------+----------------+----------------+----------------+
997 * | position low 32-bit | 12
998 * +----------------+----------------+----------------+----------------+
999 * | position high 32-bit | 16
1000 * +----------------+----------------+----------------+----------------+
1002 * +----------------+----------------+----------------+----------------+
1003 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
1004 * +----------------+----------------+----------------+----------------+
1006 * +----------------+----------------+----------------+----------------+
1008 * position - current value of stream's playback/capture position, octets
1012 struct xensnd_cur_pos_evt {
1019 uint8_t reserved[5];
1021 struct xensnd_open_req open;
1022 struct xensnd_rw_req rw;
1023 struct xensnd_trigger_req trigger;
1024 struct xensnd_query_hw_param hw_param;
1025 uint8_t reserved[56];
1029 struct xensnd_resp {
1035 struct xensnd_query_hw_param hw_param;
1036 uint8_t reserved1[56];
1043 uint8_t reserved[5];
1045 struct xensnd_cur_pos_evt cur_pos;
1046 uint8_t reserved[56];
1050 DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp);
1053 ******************************************************************************
1054 * Back to front events delivery
1055 ******************************************************************************
1056 * In order to deliver asynchronous events from back to front a shared page is
1057 * allocated by front and its granted reference propagated to back via
1058 * XenStore entries (evt-ring-ref/evt-event-channel).
1059 * This page has a common header used by both front and back to synchronize
1060 * access and control event's ring buffer, while back being a producer of the
1061 * events and front being a consumer. The rest of the page after the header
1062 * is used for event packets.
1064 * Upon reception of an event(s) front may confirm its reception
1065 * for either each event, group of events or none.
1068 struct xensnd_event_page {
1071 uint8_t reserved[56];
1074 #define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE
1075 #define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page))
1076 #define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS)
1077 #define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt))
1078 #define XENSND_IN_RING(page) \
1079 ((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS))
1080 #define XENSND_IN_RING_REF(page, idx) \
1081 (XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN])
1083 #endif /* __XEN_PUBLIC_IO_SNDIF_H__ */