1/* SPDX-License-Identifier: MIT */
2/*
3 * kbdif.h -- Xen virtual keyboard/mouse
4 *
5 * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
6 * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
7 */
8
9#ifndef __XEN_PUBLIC_IO_KBDIF_H__
10#define __XEN_PUBLIC_IO_KBDIF_H__
11
12/*
13 *****************************************************************************
14 * Feature and Parameter Negotiation
15 *****************************************************************************
16 *
17 * The two halves of a para-virtual driver utilize nodes within
18 * XenStore to communicate capabilities and to negotiate operating parameters.
19 * This section enumerates these nodes which reside in the respective front and
20 * backend portions of XenStore, following XenBus convention.
21 *
22 * All data in XenStore is stored as strings. Nodes specifying numeric
23 * values are encoded in decimal. Integer value ranges listed below are
24 * expressed as fixed sized integer types capable of storing the conversion
25 * of a properly formated node string, without loss of information.
26 *
27 *****************************************************************************
28 * Backend XenBus Nodes
29 *****************************************************************************
30 *
31 *---------------------------- Features supported ----------------------------
32 *
33 * Capable backend advertises supported features by publishing
34 * corresponding entries in XenStore and puts 1 as the value of the entry.
35 * If a feature is not supported then 0 must be set or feature entry omitted.
36 *
37 * feature-disable-keyboard
38 * Values: <uint>
39 *
40 * If there is no need to expose a virtual keyboard device by the
41 * frontend then this must be set to 1.
42 *
43 * feature-disable-pointer
44 * Values: <uint>
45 *
46 * If there is no need to expose a virtual pointer device by the
47 * frontend then this must be set to 1.
48 *
49 * feature-abs-pointer
50 * Values: <uint>
51 *
52 * Backends, which support reporting of absolute coordinates for pointer
53 * device should set this to 1.
54 *
55 * feature-multi-touch
56 * Values: <uint>
57 *
58 * Backends, which support reporting of multi-touch events
59 * should set this to 1.
60 *
61 * feature-raw-pointer
62 * Values: <uint>
63 *
64 * Backends, which support reporting raw (unscaled) absolute coordinates
65 * for pointer devices should set this to 1. Raw (unscaled) values have
66 * a range of [0, 0x7fff].
67 *
68 *----------------------- Device Instance Parameters ------------------------
69 *
70 * unique-id
71 * Values: <string>
72 *
73 * After device instance initialization it is assigned a unique ID,
74 * so every instance of the frontend can be identified by the backend
75 * by this ID. This can be UUID or such.
76 *
77 *------------------------- Pointer Device Parameters ------------------------
78 *
79 * width
80 * Values: <uint>
81 *
82 * Maximum X coordinate (width) to be used by the frontend
83 * while reporting input events, pixels, [0; UINT32_MAX].
84 *
85 * height
86 * Values: <uint>
87 *
88 * Maximum Y coordinate (height) to be used by the frontend
89 * while reporting input events, pixels, [0; UINT32_MAX].
90 *
91 *----------------------- Multi-touch Device Parameters ----------------------
92 *
93 * multi-touch-num-contacts
94 * Values: <uint>
95 *
96 * Number of simultaneous touches reported.
97 *
98 * multi-touch-width
99 * Values: <uint>
100 *
101 * Width of the touch area to be used by the frontend
102 * while reporting input events, pixels, [0; UINT32_MAX].
103 *
104 * multi-touch-height
105 * Values: <uint>
106 *
107 * Height of the touch area to be used by the frontend
108 * while reporting input events, pixels, [0; UINT32_MAX].
109 *
110 *****************************************************************************
111 * Frontend XenBus Nodes
112 *****************************************************************************
113 *
114 *------------------------------ Feature request -----------------------------
115 *
116 * Capable frontend requests features from backend via setting corresponding
117 * entries to 1 in XenStore. Requests for features not advertised as supported
118 * by the backend have no effect.
119 *
120 * request-abs-pointer
121 * Values: <uint>
122 *
123 * Request backend to report absolute pointer coordinates
124 * (XENKBD_TYPE_POS) instead of relative ones (XENKBD_TYPE_MOTION).
125 *
126 * request-multi-touch
127 * Values: <uint>
128 *
129 * Request backend to report multi-touch events.
130 *
131 * request-raw-pointer
132 * Values: <uint>
133 *
134 * Request backend to report raw unscaled absolute pointer coordinates.
135 * This option is only valid if request-abs-pointer is also set.
136 * Raw unscaled coordinates have the range [0, 0x7fff]
137 *
138 *----------------------- Request Transport Parameters -----------------------
139 *
140 * event-channel
141 * Values: <uint>
142 *
143 * The identifier of the Xen event channel used to signal activity
144 * in the ring buffer.
145 *
146 * page-gref
147 * Values: <uint>
148 *
149 * The Xen grant reference granting permission for the backend to map
150 * a sole page in a single page sized event ring buffer.
151 *
152 * page-ref
153 * Values: <uint>
154 *
155 * OBSOLETE, not recommended for use.
156 * PFN of the shared page.
157 */
158
159/*
160 * EVENT CODES.
161 */
162
163#define XENKBD_TYPE_MOTION 1
164#define XENKBD_TYPE_RESERVED 2
165#define XENKBD_TYPE_KEY 3
166#define XENKBD_TYPE_POS 4
167#define XENKBD_TYPE_MTOUCH 5
168
169/* Multi-touch event sub-codes */
170
171#define XENKBD_MT_EV_DOWN 0
172#define XENKBD_MT_EV_UP 1
173#define XENKBD_MT_EV_MOTION 2
174#define XENKBD_MT_EV_SYN 3
175#define XENKBD_MT_EV_SHAPE 4
176#define XENKBD_MT_EV_ORIENT 5
177
178/*
179 * CONSTANTS, XENSTORE FIELD AND PATH NAME STRINGS, HELPERS.
180 */
181
182#define XENKBD_DRIVER_NAME "vkbd"
183
184#define XENKBD_FIELD_FEAT_DSBL_KEYBRD "feature-disable-keyboard"
185#define XENKBD_FIELD_FEAT_DSBL_POINTER "feature-disable-pointer"
186#define XENKBD_FIELD_FEAT_ABS_POINTER "feature-abs-pointer"
187#define XENKBD_FIELD_FEAT_RAW_POINTER "feature-raw-pointer"
188#define XENKBD_FIELD_FEAT_MTOUCH "feature-multi-touch"
189#define XENKBD_FIELD_REQ_ABS_POINTER "request-abs-pointer"
190#define XENKBD_FIELD_REQ_RAW_POINTER "request-raw-pointer"
191#define XENKBD_FIELD_REQ_MTOUCH "request-multi-touch"
192#define XENKBD_FIELD_RING_GREF "page-gref"
193#define XENKBD_FIELD_EVT_CHANNEL "event-channel"
194#define XENKBD_FIELD_WIDTH "width"
195#define XENKBD_FIELD_HEIGHT "height"
196#define XENKBD_FIELD_MT_WIDTH "multi-touch-width"
197#define XENKBD_FIELD_MT_HEIGHT "multi-touch-height"
198#define XENKBD_FIELD_MT_NUM_CONTACTS "multi-touch-num-contacts"
199#define XENKBD_FIELD_UNIQUE_ID "unique-id"
200
201/* OBSOLETE, not recommended for use */
202#define XENKBD_FIELD_RING_REF "page-ref"
203
204/*
205 *****************************************************************************
206 * Description of the protocol between frontend and backend driver.
207 *****************************************************************************
208 *
209 * The two halves of a Para-virtual driver communicate with
210 * each other using a shared page and an event channel.
211 * Shared page contains a ring with event structures.
212 *
213 * All reserved fields in the structures below must be 0.
214 *
215 *****************************************************************************
216 * Backend to frontend events
217 *****************************************************************************
218 *
219 * Frontends should ignore unknown in events.
220 * All event packets have the same length (40 octets)
221 * All event packets have common header:
222 *
223 * 0 octet
224 * +-----------------+
225 * | type |
226 * +-----------------+
227 * type - uint8_t, event code, XENKBD_TYPE_???
228 *
229 *
230 * Pointer relative movement event
231 * 0 1 2 3 octet
232 * +----------------+----------------+----------------+----------------+
233 * | _TYPE_MOTION | reserved | 4
234 * +----------------+----------------+----------------+----------------+
235 * | rel_x | 8
236 * +----------------+----------------+----------------+----------------+
237 * | rel_y | 12
238 * +----------------+----------------+----------------+----------------+
239 * | rel_z | 16
240 * +----------------+----------------+----------------+----------------+
241 * | reserved | 20
242 * +----------------+----------------+----------------+----------------+
243 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
244 * +----------------+----------------+----------------+----------------+
245 * | reserved | 40
246 * +----------------+----------------+----------------+----------------+
247 *
248 * rel_x - int32_t, relative X motion
249 * rel_y - int32_t, relative Y motion
250 * rel_z - int32_t, relative Z motion (wheel)
251 */
252
253struct xenkbd_motion {
254 uint8_t type;
255 int32_t rel_x;
256 int32_t rel_y;
257 int32_t rel_z;
258};
259
260/*
261 * Key event (includes pointer buttons)
262 * 0 1 2 3 octet
263 * +----------------+----------------+----------------+----------------+
264 * | _TYPE_KEY | pressed | reserved | 4
265 * +----------------+----------------+----------------+----------------+
266 * | keycode | 8
267 * +----------------+----------------+----------------+----------------+
268 * | reserved | 12
269 * +----------------+----------------+----------------+----------------+
270 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
271 * +----------------+----------------+----------------+----------------+
272 * | reserved | 40
273 * +----------------+----------------+----------------+----------------+
274 *
275 * pressed - uint8_t, 1 if pressed; 0 otherwise
276 * keycode - uint32_t, KEY_* from linux/input.h
277 */
278
279struct xenkbd_key {
280 uint8_t type;
281 uint8_t pressed;
282 uint32_t keycode;
283};
284
285/*
286 * Pointer absolute position event
287 * 0 1 2 3 octet
288 * +----------------+----------------+----------------+----------------+
289 * | _TYPE_POS | reserved | 4
290 * +----------------+----------------+----------------+----------------+
291 * | abs_x | 8
292 * +----------------+----------------+----------------+----------------+
293 * | abs_y | 12
294 * +----------------+----------------+----------------+----------------+
295 * | rel_z | 16
296 * +----------------+----------------+----------------+----------------+
297 * | reserved | 20
298 * +----------------+----------------+----------------+----------------+
299 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
300 * +----------------+----------------+----------------+----------------+
301 * | reserved | 40
302 * +----------------+----------------+----------------+----------------+
303 *
304 * abs_x - int32_t, absolute X position (in FB pixels)
305 * abs_y - int32_t, absolute Y position (in FB pixels)
306 * rel_z - int32_t, relative Z motion (wheel)
307 */
308
309struct xenkbd_position {
310 uint8_t type;
311 int32_t abs_x;
312 int32_t abs_y;
313 int32_t rel_z;
314};
315
316/*
317 * Multi-touch event and its sub-types
318 *
319 * All multi-touch event packets have common header:
320 *
321 * 0 1 2 3 octet
322 * +----------------+----------------+----------------+----------------+
323 * | _TYPE_MTOUCH | event_type | contact_id | reserved | 4
324 * +----------------+----------------+----------------+----------------+
325 * | reserved | 8
326 * +----------------+----------------+----------------+----------------+
327 *
328 * event_type - unt8_t, multi-touch event sub-type, XENKBD_MT_EV_???
329 * contact_id - unt8_t, ID of the contact
330 *
331 * Touch interactions can consist of one or more contacts.
332 * For each contact, a series of events is generated, starting
333 * with a down event, followed by zero or more motion events,
334 * and ending with an up event. Events relating to the same
335 * contact point can be identified by the ID of the sequence: contact ID.
336 * Contact ID may be reused after XENKBD_MT_EV_UP event and
337 * is in the [0; XENKBD_FIELD_NUM_CONTACTS - 1] range.
338 *
339 * For further information please refer to documentation on Wayland [1],
340 * Linux [2] and Windows [3] multi-touch support.
341 *
342 * [1] https://cgit.freedesktop.org/wayland/wayland/tree/protocol/wayland.xml
343 * [2] https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.rst
344 * [3] https://msdn.microsoft.com/en-us/library/jj151564(v=vs.85).aspx
345 *
346 *
347 * Multi-touch down event - sent when a new touch is made: touch is assigned
348 * a unique contact ID, sent with this and consequent events related
349 * to this touch.
350 * 0 1 2 3 octet
351 * +----------------+----------------+----------------+----------------+
352 * | _TYPE_MTOUCH | _MT_EV_DOWN | contact_id | reserved | 4
353 * +----------------+----------------+----------------+----------------+
354 * | reserved | 8
355 * +----------------+----------------+----------------+----------------+
356 * | abs_x | 12
357 * +----------------+----------------+----------------+----------------+
358 * | abs_y | 16
359 * +----------------+----------------+----------------+----------------+
360 * | reserved | 20
361 * +----------------+----------------+----------------+----------------+
362 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
363 * +----------------+----------------+----------------+----------------+
364 * | reserved | 40
365 * +----------------+----------------+----------------+----------------+
366 *
367 * abs_x - int32_t, absolute X position, in pixels
368 * abs_y - int32_t, absolute Y position, in pixels
369 *
370 * Multi-touch contact release event
371 * 0 1 2 3 octet
372 * +----------------+----------------+----------------+----------------+
373 * | _TYPE_MTOUCH | _MT_EV_UP | contact_id | reserved | 4
374 * +----------------+----------------+----------------+----------------+
375 * | reserved | 8
376 * +----------------+----------------+----------------+----------------+
377 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
378 * +----------------+----------------+----------------+----------------+
379 * | reserved | 40
380 * +----------------+----------------+----------------+----------------+
381 *
382 * Multi-touch motion event
383 * 0 1 2 3 octet
384 * +----------------+----------------+----------------+----------------+
385 * | _TYPE_MTOUCH | _MT_EV_MOTION | contact_id | reserved | 4
386 * +----------------+----------------+----------------+----------------+
387 * | reserved | 8
388 * +----------------+----------------+----------------+----------------+
389 * | abs_x | 12
390 * +----------------+----------------+----------------+----------------+
391 * | abs_y | 16
392 * +----------------+----------------+----------------+----------------+
393 * | reserved | 20
394 * +----------------+----------------+----------------+----------------+
395 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
396 * +----------------+----------------+----------------+----------------+
397 * | reserved | 40
398 * +----------------+----------------+----------------+----------------+
399 *
400 * abs_x - int32_t, absolute X position, in pixels,
401 * abs_y - int32_t, absolute Y position, in pixels,
402 *
403 * Multi-touch input synchronization event - shows end of a set of events
404 * which logically belong together.
405 * 0 1 2 3 octet
406 * +----------------+----------------+----------------+----------------+
407 * | _TYPE_MTOUCH | _MT_EV_SYN | contact_id | reserved | 4
408 * +----------------+----------------+----------------+----------------+
409 * | reserved | 8
410 * +----------------+----------------+----------------+----------------+
411 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
412 * +----------------+----------------+----------------+----------------+
413 * | reserved | 40
414 * +----------------+----------------+----------------+----------------+
415 *
416 * Multi-touch shape event - touch point's shape has changed its shape.
417 * Shape is approximated by an ellipse through the major and minor axis
418 * lengths: major is the longer diameter of the ellipse and minor is the
419 * shorter one. Center of the ellipse is reported via
420 * XENKBD_MT_EV_DOWN/XENKBD_MT_EV_MOTION events.
421 * 0 1 2 3 octet
422 * +----------------+----------------+----------------+----------------+
423 * | _TYPE_MTOUCH | _MT_EV_SHAPE | contact_id | reserved | 4
424 * +----------------+----------------+----------------+----------------+
425 * | reserved | 8
426 * +----------------+----------------+----------------+----------------+
427 * | major | 12
428 * +----------------+----------------+----------------+----------------+
429 * | minor | 16
430 * +----------------+----------------+----------------+----------------+
431 * | reserved | 20
432 * +----------------+----------------+----------------+----------------+
433 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
434 * +----------------+----------------+----------------+----------------+
435 * | reserved | 40
436 * +----------------+----------------+----------------+----------------+
437 *
438 * major - unt32_t, length of the major axis, pixels
439 * minor - unt32_t, length of the minor axis, pixels
440 *
441 * Multi-touch orientation event - touch point's shape has changed
442 * its orientation: calculated as a clockwise angle between the major axis
443 * of the ellipse and positive Y axis in degrees, [-180; +180].
444 * 0 1 2 3 octet
445 * +----------------+----------------+----------------+----------------+
446 * | _TYPE_MTOUCH | _MT_EV_ORIENT | contact_id | reserved | 4
447 * +----------------+----------------+----------------+----------------+
448 * | reserved | 8
449 * +----------------+----------------+----------------+----------------+
450 * | orientation | reserved | 12
451 * +----------------+----------------+----------------+----------------+
452 * | reserved | 16
453 * +----------------+----------------+----------------+----------------+
454 * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
455 * +----------------+----------------+----------------+----------------+
456 * | reserved | 40
457 * +----------------+----------------+----------------+----------------+
458 *
459 * orientation - int16_t, clockwise angle of the major axis
460 */
461
462struct xenkbd_mtouch {
463 uint8_t type; /* XENKBD_TYPE_MTOUCH */
464 uint8_t event_type; /* XENKBD_MT_EV_??? */
465 uint8_t contact_id;
466 uint8_t reserved[5]; /* reserved for the future use */
467 union {
468 struct {
469 int32_t abs_x; /* absolute X position, pixels */
470 int32_t abs_y; /* absolute Y position, pixels */
471 } pos;
472 struct {
473 uint32_t major; /* length of the major axis, pixels */
474 uint32_t minor; /* length of the minor axis, pixels */
475 } shape;
476 int16_t orientation; /* clockwise angle of the major axis */
477 } u;
478};
479
480#define XENKBD_IN_EVENT_SIZE 40
481
482union xenkbd_in_event {
483 uint8_t type;
484 struct xenkbd_motion motion;
485 struct xenkbd_key key;
486 struct xenkbd_position pos;
487 struct xenkbd_mtouch mtouch;
488 char pad[XENKBD_IN_EVENT_SIZE];
489};
490
491/*
492 *****************************************************************************
493 * Frontend to backend events
494 *****************************************************************************
495 *
496 * Out events may be sent only when requested by backend, and receipt
497 * of an unknown out event is an error.
498 * No out events currently defined.
499
500 * All event packets have the same length (40 octets)
501 * All event packets have common header:
502 * 0 octet
503 * +-----------------+
504 * | type |
505 * +-----------------+
506 * type - uint8_t, event code
507 */
508
509#define XENKBD_OUT_EVENT_SIZE 40
510
511union xenkbd_out_event {
512 uint8_t type;
513 char pad[XENKBD_OUT_EVENT_SIZE];
514};
515
516/*
517 *****************************************************************************
518 * Shared page
519 *****************************************************************************
520 */
521
522#define XENKBD_IN_RING_SIZE 2048
523#define XENKBD_IN_RING_LEN (XENKBD_IN_RING_SIZE / XENKBD_IN_EVENT_SIZE)
524#define XENKBD_IN_RING_OFFS 1024
525#define XENKBD_IN_RING(page) \
526 ((union xenkbd_in_event *)((char *)(page) + XENKBD_IN_RING_OFFS))
527#define XENKBD_IN_RING_REF(page, idx) \
528 (XENKBD_IN_RING((page))[(idx) % XENKBD_IN_RING_LEN])
529
530#define XENKBD_OUT_RING_SIZE 1024
531#define XENKBD_OUT_RING_LEN (XENKBD_OUT_RING_SIZE / XENKBD_OUT_EVENT_SIZE)
532#define XENKBD_OUT_RING_OFFS (XENKBD_IN_RING_OFFS + XENKBD_IN_RING_SIZE)
533#define XENKBD_OUT_RING(page) \
534 ((union xenkbd_out_event *)((char *)(page) + XENKBD_OUT_RING_OFFS))
535#define XENKBD_OUT_RING_REF(page, idx) \
536 (XENKBD_OUT_RING((page))[(idx) % XENKBD_OUT_RING_LEN])
537
538struct xenkbd_page {
539 uint32_t in_cons, in_prod;
540 uint32_t out_cons, out_prod;
541};
542
543#endif /* __XEN_PUBLIC_IO_KBDIF_H__ */
544

source code of linux/include/xen/interface/io/kbdif.h