xref: /openbmc/qemu/include/hw/xen/interface/io/kbdif.h (revision ffe98631)
1 /*
2  * kbdif.h -- Xen virtual keyboard/mouse
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to
6  * deal in the Software without restriction, including without limitation the
7  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
8  * sell copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20  * DEALINGS IN THE SOFTWARE.
21  *
22  * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
23  * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
24  */
25 
26 #ifndef __XEN_PUBLIC_IO_KBDIF_H__
27 #define __XEN_PUBLIC_IO_KBDIF_H__
28 
29 /*
30  *****************************************************************************
31  *                     Feature and Parameter Negotiation
32  *****************************************************************************
33  *
34  * The two halves of a para-virtual driver utilize nodes within
35  * XenStore to communicate capabilities and to negotiate operating parameters.
36  * This section enumerates these nodes which reside in the respective front and
37  * backend portions of XenStore, following XenBus convention.
38  *
39  * All data in XenStore is stored as strings.  Nodes specifying numeric
40  * values are encoded in decimal. Integer value ranges listed below are
41  * expressed as fixed sized integer types capable of storing the conversion
42  * of a properly formated node string, without loss of information.
43  *
44  *****************************************************************************
45  *                            Backend XenBus Nodes
46  *****************************************************************************
47  *
48  *---------------------------- Features supported ----------------------------
49  *
50  * Capable backend advertises supported features by publishing
51  * corresponding entries in XenStore and puts 1 as the value of the entry.
52  * If a feature is not supported then 0 must be set or feature entry omitted.
53  *
54  * feature-disable-keyboard
55  *      Values:         <uint>
56  *
57  *      If there is no need to expose a virtual keyboard device by the
58  *      frontend then this must be set to 1.
59  *
60  * feature-disable-pointer
61  *      Values:         <uint>
62  *
63  *      If there is no need to expose a virtual pointer device by the
64  *      frontend then this must be set to 1.
65  *
66  * feature-abs-pointer
67  *      Values:         <uint>
68  *
69  *      Backends, which support reporting of absolute coordinates for pointer
70  *      device should set this to 1.
71  *
72  * feature-multi-touch
73  *      Values:         <uint>
74  *
75  *      Backends, which support reporting of multi-touch events
76  *      should set this to 1.
77  *
78  * feature-raw-pointer
79  *      Values:        <uint>
80  *
81  *      Backends, which support reporting raw (unscaled) absolute coordinates
82  *      for pointer devices should set this to 1. Raw (unscaled) values have
83  *      a range of [0, 0x7fff].
84  *
85  *-----------------------  Device Instance Parameters ------------------------
86  *
87  * unique-id
88  *      Values:         <string>
89  *
90  *      After device instance initialization it is assigned a unique ID,
91  *      so every instance of the frontend can be identified by the backend
92  *      by this ID. This can be UUID or such.
93  *
94  *------------------------- Pointer Device Parameters ------------------------
95  *
96  * width
97  *      Values:         <uint>
98  *
99  *      Maximum X coordinate (width) to be used by the frontend
100  *      while reporting input events, pixels, [0; UINT32_MAX].
101  *
102  * height
103  *      Values:         <uint>
104  *
105  *      Maximum Y coordinate (height) to be used by the frontend
106  *      while reporting input events, pixels, [0; UINT32_MAX].
107  *
108  *----------------------- Multi-touch Device Parameters ----------------------
109  *
110  * multi-touch-num-contacts
111  *      Values:         <uint>
112  *
113  *      Number of simultaneous touches reported.
114  *
115  * multi-touch-width
116  *      Values:         <uint>
117  *
118  *      Width of the touch area to be used by the frontend
119  *      while reporting input events, pixels, [0; UINT32_MAX].
120  *
121  * multi-touch-height
122  *      Values:         <uint>
123  *
124  *      Height of the touch area to be used by the frontend
125  *      while reporting input events, pixels, [0; UINT32_MAX].
126  *
127  *****************************************************************************
128  *                            Frontend XenBus Nodes
129  *****************************************************************************
130  *
131  *------------------------------ Feature request -----------------------------
132  *
133  * Capable frontend requests features from backend via setting corresponding
134  * entries to 1 in XenStore. Requests for features not advertised as supported
135  * by the backend have no effect.
136  *
137  * request-abs-pointer
138  *      Values:         <uint>
139  *
140  *      Request backend to report absolute pointer coordinates
141  *      (XENKBD_TYPE_POS) instead of relative ones (XENKBD_TYPE_MOTION).
142  *
143  * request-multi-touch
144  *      Values:         <uint>
145  *
146  *      Request backend to report multi-touch events.
147  *
148  * request-raw-pointer
149  *      Values:         <uint>
150  *
151  *      Request backend to report raw unscaled absolute pointer coordinates.
152  *      This option is only valid if request-abs-pointer is also set.
153  *      Raw unscaled coordinates have the range [0, 0x7fff]
154  *
155  *----------------------- Request Transport Parameters -----------------------
156  *
157  * event-channel
158  *      Values:         <uint>
159  *
160  *      The identifier of the Xen event channel used to signal activity
161  *      in the ring buffer.
162  *
163  * page-gref
164  *      Values:         <uint>
165  *
166  *      The Xen grant reference granting permission for the backend to map
167  *      a sole page in a single page sized event ring buffer.
168  *
169  * page-ref
170  *      Values:         <uint>
171  *
172  *      OBSOLETE, not recommended for use.
173  *      PFN of the shared page.
174  */
175 
176 /*
177  * EVENT CODES.
178  */
179 
180 #define XENKBD_TYPE_MOTION             1
181 #define XENKBD_TYPE_RESERVED           2
182 #define XENKBD_TYPE_KEY                3
183 #define XENKBD_TYPE_POS                4
184 #define XENKBD_TYPE_MTOUCH             5
185 
186 /* Multi-touch event sub-codes */
187 
188 #define XENKBD_MT_EV_DOWN              0
189 #define XENKBD_MT_EV_UP                1
190 #define XENKBD_MT_EV_MOTION            2
191 #define XENKBD_MT_EV_SYN               3
192 #define XENKBD_MT_EV_SHAPE             4
193 #define XENKBD_MT_EV_ORIENT            5
194 
195 /*
196  * CONSTANTS, XENSTORE FIELD AND PATH NAME STRINGS, HELPERS.
197  */
198 
199 #define XENKBD_DRIVER_NAME             "vkbd"
200 
201 #define XENKBD_FIELD_FEAT_DSBL_KEYBRD  "feature-disable-keyboard"
202 #define XENKBD_FIELD_FEAT_DSBL_POINTER "feature-disable-pointer"
203 #define XENKBD_FIELD_FEAT_ABS_POINTER  "feature-abs-pointer"
204 #define XENKBD_FIELD_FEAT_RAW_POINTER  "feature-raw-pointer"
205 #define XENKBD_FIELD_FEAT_MTOUCH       "feature-multi-touch"
206 #define XENKBD_FIELD_REQ_ABS_POINTER   "request-abs-pointer"
207 #define XENKBD_FIELD_REQ_RAW_POINTER   "request-raw-pointer"
208 #define XENKBD_FIELD_REQ_MTOUCH        "request-multi-touch"
209 #define XENKBD_FIELD_RING_GREF         "page-gref"
210 #define XENKBD_FIELD_EVT_CHANNEL       "event-channel"
211 #define XENKBD_FIELD_WIDTH             "width"
212 #define XENKBD_FIELD_HEIGHT            "height"
213 #define XENKBD_FIELD_MT_WIDTH          "multi-touch-width"
214 #define XENKBD_FIELD_MT_HEIGHT         "multi-touch-height"
215 #define XENKBD_FIELD_MT_NUM_CONTACTS   "multi-touch-num-contacts"
216 #define XENKBD_FIELD_UNIQUE_ID         "unique-id"
217 
218 /* OBSOLETE, not recommended for use */
219 #define XENKBD_FIELD_RING_REF          "page-ref"
220 
221 /*
222  *****************************************************************************
223  * Description of the protocol between frontend and backend driver.
224  *****************************************************************************
225  *
226  * The two halves of a Para-virtual driver communicate with
227  * each other using a shared page and an event channel.
228  * Shared page contains a ring with event structures.
229  *
230  * All reserved fields in the structures below must be 0.
231  *
232  *****************************************************************************
233  *                           Backend to frontend events
234  *****************************************************************************
235  *
236  * Frontends should ignore unknown in events.
237  * All event packets have the same length (40 octets)
238  * All event packets have common header:
239  *
240  *          0         octet
241  * +-----------------+
242  * |       type      |
243  * +-----------------+
244  * type - uint8_t, event code, XENKBD_TYPE_???
245  *
246  *
247  * Pointer relative movement event
248  *         0                1                 2               3        octet
249  * +----------------+----------------+----------------+----------------+
250  * |  _TYPE_MOTION  |                     reserved                     | 4
251  * +----------------+----------------+----------------+----------------+
252  * |                               rel_x                               | 8
253  * +----------------+----------------+----------------+----------------+
254  * |                               rel_y                               | 12
255  * +----------------+----------------+----------------+----------------+
256  * |                               rel_z                               | 16
257  * +----------------+----------------+----------------+----------------+
258  * |                             reserved                              | 20
259  * +----------------+----------------+----------------+----------------+
260  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
261  * +----------------+----------------+----------------+----------------+
262  * |                             reserved                              | 40
263  * +----------------+----------------+----------------+----------------+
264  *
265  * rel_x - int32_t, relative X motion
266  * rel_y - int32_t, relative Y motion
267  * rel_z - int32_t, relative Z motion (wheel)
268  */
269 
270 struct xenkbd_motion
271 {
272     uint8_t type;
273     int32_t rel_x;
274     int32_t rel_y;
275     int32_t rel_z;
276 };
277 
278 /*
279  * Key event (includes pointer buttons)
280  *         0                1                 2               3        octet
281  * +----------------+----------------+----------------+----------------+
282  * |  _TYPE_KEY     |     pressed    |            reserved             | 4
283  * +----------------+----------------+----------------+----------------+
284  * |                              keycode                              | 8
285  * +----------------+----------------+----------------+----------------+
286  * |                             reserved                              | 12
287  * +----------------+----------------+----------------+----------------+
288  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
289  * +----------------+----------------+----------------+----------------+
290  * |                             reserved                              | 40
291  * +----------------+----------------+----------------+----------------+
292  *
293  * pressed - uint8_t, 1 if pressed; 0 otherwise
294  * keycode - uint32_t, KEY_* from linux/input.h
295  */
296 
297 struct xenkbd_key
298 {
299     uint8_t type;
300     uint8_t pressed;
301     uint32_t keycode;
302 };
303 
304 /*
305  * Pointer absolute position event
306  *         0                1                 2               3        octet
307  * +----------------+----------------+----------------+----------------+
308  * |  _TYPE_POS     |                     reserved                     | 4
309  * +----------------+----------------+----------------+----------------+
310  * |                               abs_x                               | 8
311  * +----------------+----------------+----------------+----------------+
312  * |                               abs_y                               | 12
313  * +----------------+----------------+----------------+----------------+
314  * |                               rel_z                               | 16
315  * +----------------+----------------+----------------+----------------+
316  * |                             reserved                              | 20
317  * +----------------+----------------+----------------+----------------+
318  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
319  * +----------------+----------------+----------------+----------------+
320  * |                             reserved                              | 40
321  * +----------------+----------------+----------------+----------------+
322  *
323  * abs_x - int32_t, absolute X position (in FB pixels)
324  * abs_y - int32_t, absolute Y position (in FB pixels)
325  * rel_z - int32_t, relative Z motion (wheel)
326  */
327 
328 struct xenkbd_position
329 {
330     uint8_t type;
331     int32_t abs_x;
332     int32_t abs_y;
333     int32_t rel_z;
334 };
335 
336 /*
337  * Multi-touch event and its sub-types
338  *
339  * All multi-touch event packets have common header:
340  *
341  *         0                1                 2               3        octet
342  * +----------------+----------------+----------------+----------------+
343  * |  _TYPE_MTOUCH  |   event_type   |   contact_id   |    reserved    | 4
344  * +----------------+----------------+----------------+----------------+
345  * |                             reserved                              | 8
346  * +----------------+----------------+----------------+----------------+
347  *
348  * event_type - unt8_t, multi-touch event sub-type, XENKBD_MT_EV_???
349  * contact_id - unt8_t, ID of the contact
350  *
351  * Touch interactions can consist of one or more contacts.
352  * For each contact, a series of events is generated, starting
353  * with a down event, followed by zero or more motion events,
354  * and ending with an up event. Events relating to the same
355  * contact point can be identified by the ID of the sequence: contact ID.
356  * Contact ID may be reused after XENKBD_MT_EV_UP event and
357  * is in the [0; XENKBD_FIELD_NUM_CONTACTS - 1] range.
358  *
359  * For further information please refer to documentation on Wayland [1],
360  * Linux [2] and Windows [3] multi-touch support.
361  *
362  * [1] https://cgit.freedesktop.org/wayland/wayland/tree/protocol/wayland.xml
363  * [2] https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt
364  * [3] https://msdn.microsoft.com/en-us/library/jj151564(v=vs.85).aspx
365  *
366  *
367  * Multi-touch down event - sent when a new touch is made: touch is assigned
368  * a unique contact ID, sent with this and consequent events related
369  * to this touch.
370  *         0                1                 2               3        octet
371  * +----------------+----------------+----------------+----------------+
372  * |  _TYPE_MTOUCH  |   _MT_EV_DOWN  |   contact_id   |    reserved    | 4
373  * +----------------+----------------+----------------+----------------+
374  * |                             reserved                              | 8
375  * +----------------+----------------+----------------+----------------+
376  * |                               abs_x                               | 12
377  * +----------------+----------------+----------------+----------------+
378  * |                               abs_y                               | 16
379  * +----------------+----------------+----------------+----------------+
380  * |                             reserved                              | 20
381  * +----------------+----------------+----------------+----------------+
382  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
383  * +----------------+----------------+----------------+----------------+
384  * |                             reserved                              | 40
385  * +----------------+----------------+----------------+----------------+
386  *
387  * abs_x - int32_t, absolute X position, in pixels
388  * abs_y - int32_t, absolute Y position, in pixels
389  *
390  * Multi-touch contact release event
391  *         0                1                 2               3        octet
392  * +----------------+----------------+----------------+----------------+
393  * |  _TYPE_MTOUCH  |  _MT_EV_UP     |   contact_id   |    reserved    | 4
394  * +----------------+----------------+----------------+----------------+
395  * |                             reserved                              | 8
396  * +----------------+----------------+----------------+----------------+
397  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
398  * +----------------+----------------+----------------+----------------+
399  * |                             reserved                              | 40
400  * +----------------+----------------+----------------+----------------+
401  *
402  * Multi-touch motion event
403  *         0                1                 2               3        octet
404  * +----------------+----------------+----------------+----------------+
405  * |  _TYPE_MTOUCH  |  _MT_EV_MOTION |   contact_id   |    reserved    | 4
406  * +----------------+----------------+----------------+----------------+
407  * |                             reserved                              | 8
408  * +----------------+----------------+----------------+----------------+
409  * |                               abs_x                               | 12
410  * +----------------+----------------+----------------+----------------+
411  * |                               abs_y                               | 16
412  * +----------------+----------------+----------------+----------------+
413  * |                             reserved                              | 20
414  * +----------------+----------------+----------------+----------------+
415  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
416  * +----------------+----------------+----------------+----------------+
417  * |                             reserved                              | 40
418  * +----------------+----------------+----------------+----------------+
419  *
420  * abs_x - int32_t, absolute X position, in pixels,
421  * abs_y - int32_t, absolute Y position, in pixels,
422  *
423  * Multi-touch input synchronization event - shows end of a set of events
424  * which logically belong together.
425  *         0                1                 2               3        octet
426  * +----------------+----------------+----------------+----------------+
427  * |  _TYPE_MTOUCH  |  _MT_EV_SYN    |   contact_id   |    reserved    | 4
428  * +----------------+----------------+----------------+----------------+
429  * |                             reserved                              | 8
430  * +----------------+----------------+----------------+----------------+
431  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
432  * +----------------+----------------+----------------+----------------+
433  * |                             reserved                              | 40
434  * +----------------+----------------+----------------+----------------+
435  *
436  * Multi-touch shape event - touch point's shape has changed its shape.
437  * Shape is approximated by an ellipse through the major and minor axis
438  * lengths: major is the longer diameter of the ellipse and minor is the
439  * shorter one. Center of the ellipse is reported via
440  * XENKBD_MT_EV_DOWN/XENKBD_MT_EV_MOTION events.
441  *         0                1                 2               3        octet
442  * +----------------+----------------+----------------+----------------+
443  * |  _TYPE_MTOUCH  |  _MT_EV_SHAPE  |   contact_id   |    reserved    | 4
444  * +----------------+----------------+----------------+----------------+
445  * |                             reserved                              | 8
446  * +----------------+----------------+----------------+----------------+
447  * |                               major                               | 12
448  * +----------------+----------------+----------------+----------------+
449  * |                               minor                               | 16
450  * +----------------+----------------+----------------+----------------+
451  * |                             reserved                              | 20
452  * +----------------+----------------+----------------+----------------+
453  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
454  * +----------------+----------------+----------------+----------------+
455  * |                             reserved                              | 40
456  * +----------------+----------------+----------------+----------------+
457  *
458  * major - unt32_t, length of the major axis, pixels
459  * minor - unt32_t, length of the minor axis, pixels
460  *
461  * Multi-touch orientation event - touch point's shape has changed
462  * its orientation: calculated as a clockwise angle between the major axis
463  * of the ellipse and positive Y axis in degrees, [-180; +180].
464  *         0                1                 2               3        octet
465  * +----------------+----------------+----------------+----------------+
466  * |  _TYPE_MTOUCH  |  _MT_EV_ORIENT |   contact_id   |    reserved    | 4
467  * +----------------+----------------+----------------+----------------+
468  * |                             reserved                              | 8
469  * +----------------+----------------+----------------+----------------+
470  * |           orientation           |            reserved             | 12
471  * +----------------+----------------+----------------+----------------+
472  * |                             reserved                              | 16
473  * +----------------+----------------+----------------+----------------+
474  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
475  * +----------------+----------------+----------------+----------------+
476  * |                             reserved                              | 40
477  * +----------------+----------------+----------------+----------------+
478  *
479  * orientation - int16_t, clockwise angle of the major axis
480  */
481 
482 struct xenkbd_mtouch {
483     uint8_t type;            /* XENKBD_TYPE_MTOUCH */
484     uint8_t event_type;      /* XENKBD_MT_EV_??? */
485     uint8_t contact_id;
486     uint8_t reserved[5];     /* reserved for the future use */
487     union {
488         struct {
489             int32_t abs_x;   /* absolute X position, pixels */
490             int32_t abs_y;   /* absolute Y position, pixels */
491         } pos;
492         struct {
493             uint32_t major;  /* length of the major axis, pixels */
494             uint32_t minor;  /* length of the minor axis, pixels */
495         } shape;
496         int16_t orientation; /* clockwise angle of the major axis */
497     } u;
498 };
499 
500 #define XENKBD_IN_EVENT_SIZE 40
501 
502 union xenkbd_in_event
503 {
504     uint8_t type;
505     struct xenkbd_motion motion;
506     struct xenkbd_key key;
507     struct xenkbd_position pos;
508     struct xenkbd_mtouch mtouch;
509     char pad[XENKBD_IN_EVENT_SIZE];
510 };
511 
512 /*
513  *****************************************************************************
514  *                            Frontend to backend events
515  *****************************************************************************
516  *
517  * Out events may be sent only when requested by backend, and receipt
518  * of an unknown out event is an error.
519  * No out events currently defined.
520 
521  * All event packets have the same length (40 octets)
522  * All event packets have common header:
523  *          0         octet
524  * +-----------------+
525  * |       type      |
526  * +-----------------+
527  * type - uint8_t, event code
528  */
529 
530 #define XENKBD_OUT_EVENT_SIZE 40
531 
532 union xenkbd_out_event
533 {
534     uint8_t type;
535     char pad[XENKBD_OUT_EVENT_SIZE];
536 };
537 
538 /*
539  *****************************************************************************
540  *                            Shared page
541  *****************************************************************************
542  */
543 
544 #define XENKBD_IN_RING_SIZE 2048
545 #define XENKBD_IN_RING_LEN (XENKBD_IN_RING_SIZE / XENKBD_IN_EVENT_SIZE)
546 #define XENKBD_IN_RING_OFFS 1024
547 #define XENKBD_IN_RING(page) \
548     ((union xenkbd_in_event *)((char *)(page) + XENKBD_IN_RING_OFFS))
549 #define XENKBD_IN_RING_REF(page, idx) \
550     (XENKBD_IN_RING((page))[(idx) % XENKBD_IN_RING_LEN])
551 
552 #define XENKBD_OUT_RING_SIZE 1024
553 #define XENKBD_OUT_RING_LEN (XENKBD_OUT_RING_SIZE / XENKBD_OUT_EVENT_SIZE)
554 #define XENKBD_OUT_RING_OFFS (XENKBD_IN_RING_OFFS + XENKBD_IN_RING_SIZE)
555 #define XENKBD_OUT_RING(page) \
556     ((union xenkbd_out_event *)((char *)(page) + XENKBD_OUT_RING_OFFS))
557 #define XENKBD_OUT_RING_REF(page, idx) \
558     (XENKBD_OUT_RING((page))[(idx) % XENKBD_OUT_RING_LEN])
559 
560 struct xenkbd_page
561 {
562     uint32_t in_cons, in_prod;
563     uint32_t out_cons, out_prod;
564 };
565 
566 #endif /* __XEN_PUBLIC_IO_KBDIF_H__ */
567