xref: /openbmc/qemu/include/hw/xen/interface/io/kbdif.h (revision 7200fb21)
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 
253 struct xenkbd_motion
254 {
255     uint8_t type;
256     int32_t rel_x;
257     int32_t rel_y;
258     int32_t rel_z;
259 };
260 
261 /*
262  * Key event (includes pointer buttons)
263  *         0                1                 2               3        octet
264  * +----------------+----------------+----------------+----------------+
265  * |  _TYPE_KEY     |     pressed    |            reserved             | 4
266  * +----------------+----------------+----------------+----------------+
267  * |                              keycode                              | 8
268  * +----------------+----------------+----------------+----------------+
269  * |                             reserved                              | 12
270  * +----------------+----------------+----------------+----------------+
271  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
272  * +----------------+----------------+----------------+----------------+
273  * |                             reserved                              | 40
274  * +----------------+----------------+----------------+----------------+
275  *
276  * pressed - uint8_t, 1 if pressed; 0 otherwise
277  * keycode - uint32_t, KEY_* from linux/input.h
278  */
279 
280 struct xenkbd_key
281 {
282     uint8_t type;
283     uint8_t pressed;
284     uint32_t keycode;
285 };
286 
287 /*
288  * Pointer absolute position event
289  *         0                1                 2               3        octet
290  * +----------------+----------------+----------------+----------------+
291  * |  _TYPE_POS     |                     reserved                     | 4
292  * +----------------+----------------+----------------+----------------+
293  * |                               abs_x                               | 8
294  * +----------------+----------------+----------------+----------------+
295  * |                               abs_y                               | 12
296  * +----------------+----------------+----------------+----------------+
297  * |                               rel_z                               | 16
298  * +----------------+----------------+----------------+----------------+
299  * |                             reserved                              | 20
300  * +----------------+----------------+----------------+----------------+
301  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
302  * +----------------+----------------+----------------+----------------+
303  * |                             reserved                              | 40
304  * +----------------+----------------+----------------+----------------+
305  *
306  * abs_x - int32_t, absolute X position (in FB pixels)
307  * abs_y - int32_t, absolute Y position (in FB pixels)
308  * rel_z - int32_t, relative Z motion (wheel)
309  */
310 
311 struct xenkbd_position
312 {
313     uint8_t type;
314     int32_t abs_x;
315     int32_t abs_y;
316     int32_t rel_z;
317 };
318 
319 /*
320  * Multi-touch event and its sub-types
321  *
322  * All multi-touch event packets have common header:
323  *
324  *         0                1                 2               3        octet
325  * +----------------+----------------+----------------+----------------+
326  * |  _TYPE_MTOUCH  |   event_type   |   contact_id   |    reserved    | 4
327  * +----------------+----------------+----------------+----------------+
328  * |                             reserved                              | 8
329  * +----------------+----------------+----------------+----------------+
330  *
331  * event_type - unt8_t, multi-touch event sub-type, XENKBD_MT_EV_???
332  * contact_id - unt8_t, ID of the contact
333  *
334  * Touch interactions can consist of one or more contacts.
335  * For each contact, a series of events is generated, starting
336  * with a down event, followed by zero or more motion events,
337  * and ending with an up event. Events relating to the same
338  * contact point can be identified by the ID of the sequence: contact ID.
339  * Contact ID may be reused after XENKBD_MT_EV_UP event and
340  * is in the [0; XENKBD_FIELD_NUM_CONTACTS - 1] range.
341  *
342  * For further information please refer to documentation on Wayland [1],
343  * Linux [2] and Windows [3] multi-touch support.
344  *
345  * [1] https://cgit.freedesktop.org/wayland/wayland/tree/protocol/wayland.xml
346  * [2] https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt
347  * [3] https://msdn.microsoft.com/en-us/library/jj151564(v=vs.85).aspx
348  *
349  *
350  * Multi-touch down event - sent when a new touch is made: touch is assigned
351  * a unique contact ID, sent with this and consequent events related
352  * to this touch.
353  *         0                1                 2               3        octet
354  * +----------------+----------------+----------------+----------------+
355  * |  _TYPE_MTOUCH  |   _MT_EV_DOWN  |   contact_id   |    reserved    | 4
356  * +----------------+----------------+----------------+----------------+
357  * |                             reserved                              | 8
358  * +----------------+----------------+----------------+----------------+
359  * |                               abs_x                               | 12
360  * +----------------+----------------+----------------+----------------+
361  * |                               abs_y                               | 16
362  * +----------------+----------------+----------------+----------------+
363  * |                             reserved                              | 20
364  * +----------------+----------------+----------------+----------------+
365  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
366  * +----------------+----------------+----------------+----------------+
367  * |                             reserved                              | 40
368  * +----------------+----------------+----------------+----------------+
369  *
370  * abs_x - int32_t, absolute X position, in pixels
371  * abs_y - int32_t, absolute Y position, in pixels
372  *
373  * Multi-touch contact release event
374  *         0                1                 2               3        octet
375  * +----------------+----------------+----------------+----------------+
376  * |  _TYPE_MTOUCH  |  _MT_EV_UP     |   contact_id   |    reserved    | 4
377  * +----------------+----------------+----------------+----------------+
378  * |                             reserved                              | 8
379  * +----------------+----------------+----------------+----------------+
380  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
381  * +----------------+----------------+----------------+----------------+
382  * |                             reserved                              | 40
383  * +----------------+----------------+----------------+----------------+
384  *
385  * Multi-touch motion event
386  *         0                1                 2               3        octet
387  * +----------------+----------------+----------------+----------------+
388  * |  _TYPE_MTOUCH  |  _MT_EV_MOTION |   contact_id   |    reserved    | 4
389  * +----------------+----------------+----------------+----------------+
390  * |                             reserved                              | 8
391  * +----------------+----------------+----------------+----------------+
392  * |                               abs_x                               | 12
393  * +----------------+----------------+----------------+----------------+
394  * |                               abs_y                               | 16
395  * +----------------+----------------+----------------+----------------+
396  * |                             reserved                              | 20
397  * +----------------+----------------+----------------+----------------+
398  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
399  * +----------------+----------------+----------------+----------------+
400  * |                             reserved                              | 40
401  * +----------------+----------------+----------------+----------------+
402  *
403  * abs_x - int32_t, absolute X position, in pixels,
404  * abs_y - int32_t, absolute Y position, in pixels,
405  *
406  * Multi-touch input synchronization event - shows end of a set of events
407  * which logically belong together.
408  *         0                1                 2               3        octet
409  * +----------------+----------------+----------------+----------------+
410  * |  _TYPE_MTOUCH  |  _MT_EV_SYN    |   contact_id   |    reserved    | 4
411  * +----------------+----------------+----------------+----------------+
412  * |                             reserved                              | 8
413  * +----------------+----------------+----------------+----------------+
414  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
415  * +----------------+----------------+----------------+----------------+
416  * |                             reserved                              | 40
417  * +----------------+----------------+----------------+----------------+
418  *
419  * Multi-touch shape event - touch point's shape has changed its shape.
420  * Shape is approximated by an ellipse through the major and minor axis
421  * lengths: major is the longer diameter of the ellipse and minor is the
422  * shorter one. Center of the ellipse is reported via
423  * XENKBD_MT_EV_DOWN/XENKBD_MT_EV_MOTION events.
424  *         0                1                 2               3        octet
425  * +----------------+----------------+----------------+----------------+
426  * |  _TYPE_MTOUCH  |  _MT_EV_SHAPE  |   contact_id   |    reserved    | 4
427  * +----------------+----------------+----------------+----------------+
428  * |                             reserved                              | 8
429  * +----------------+----------------+----------------+----------------+
430  * |                               major                               | 12
431  * +----------------+----------------+----------------+----------------+
432  * |                               minor                               | 16
433  * +----------------+----------------+----------------+----------------+
434  * |                             reserved                              | 20
435  * +----------------+----------------+----------------+----------------+
436  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
437  * +----------------+----------------+----------------+----------------+
438  * |                             reserved                              | 40
439  * +----------------+----------------+----------------+----------------+
440  *
441  * major - unt32_t, length of the major axis, pixels
442  * minor - unt32_t, length of the minor axis, pixels
443  *
444  * Multi-touch orientation event - touch point's shape has changed
445  * its orientation: calculated as a clockwise angle between the major axis
446  * of the ellipse and positive Y axis in degrees, [-180; +180].
447  *         0                1                 2               3        octet
448  * +----------------+----------------+----------------+----------------+
449  * |  _TYPE_MTOUCH  |  _MT_EV_ORIENT |   contact_id   |    reserved    | 4
450  * +----------------+----------------+----------------+----------------+
451  * |                             reserved                              | 8
452  * +----------------+----------------+----------------+----------------+
453  * |           orientation           |            reserved             | 12
454  * +----------------+----------------+----------------+----------------+
455  * |                             reserved                              | 16
456  * +----------------+----------------+----------------+----------------+
457  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
458  * +----------------+----------------+----------------+----------------+
459  * |                             reserved                              | 40
460  * +----------------+----------------+----------------+----------------+
461  *
462  * orientation - int16_t, clockwise angle of the major axis
463  */
464 
465 struct xenkbd_mtouch {
466     uint8_t type;            /* XENKBD_TYPE_MTOUCH */
467     uint8_t event_type;      /* XENKBD_MT_EV_??? */
468     uint8_t contact_id;
469     uint8_t reserved[5];     /* reserved for the future use */
470     union {
471         struct {
472             int32_t abs_x;   /* absolute X position, pixels */
473             int32_t abs_y;   /* absolute Y position, pixels */
474         } pos;
475         struct {
476             uint32_t major;  /* length of the major axis, pixels */
477             uint32_t minor;  /* length of the minor axis, pixels */
478         } shape;
479         int16_t orientation; /* clockwise angle of the major axis */
480     } u;
481 };
482 
483 #define XENKBD_IN_EVENT_SIZE 40
484 
485 union xenkbd_in_event
486 {
487     uint8_t type;
488     struct xenkbd_motion motion;
489     struct xenkbd_key key;
490     struct xenkbd_position pos;
491     struct xenkbd_mtouch mtouch;
492     char pad[XENKBD_IN_EVENT_SIZE];
493 };
494 
495 /*
496  *****************************************************************************
497  *                            Frontend to backend events
498  *****************************************************************************
499  *
500  * Out events may be sent only when requested by backend, and receipt
501  * of an unknown out event is an error.
502  * No out events currently defined.
503 
504  * All event packets have the same length (40 octets)
505  * All event packets have common header:
506  *          0         octet
507  * +-----------------+
508  * |       type      |
509  * +-----------------+
510  * type - uint8_t, event code
511  */
512 
513 #define XENKBD_OUT_EVENT_SIZE 40
514 
515 union xenkbd_out_event
516 {
517     uint8_t type;
518     char pad[XENKBD_OUT_EVENT_SIZE];
519 };
520 
521 /*
522  *****************************************************************************
523  *                            Shared page
524  *****************************************************************************
525  */
526 
527 #define XENKBD_IN_RING_SIZE 2048
528 #define XENKBD_IN_RING_LEN (XENKBD_IN_RING_SIZE / XENKBD_IN_EVENT_SIZE)
529 #define XENKBD_IN_RING_OFFS 1024
530 #define XENKBD_IN_RING(page) \
531     ((union xenkbd_in_event *)((char *)(page) + XENKBD_IN_RING_OFFS))
532 #define XENKBD_IN_RING_REF(page, idx) \
533     (XENKBD_IN_RING((page))[(idx) % XENKBD_IN_RING_LEN])
534 
535 #define XENKBD_OUT_RING_SIZE 1024
536 #define XENKBD_OUT_RING_LEN (XENKBD_OUT_RING_SIZE / XENKBD_OUT_EVENT_SIZE)
537 #define XENKBD_OUT_RING_OFFS (XENKBD_IN_RING_OFFS + XENKBD_IN_RING_SIZE)
538 #define XENKBD_OUT_RING(page) \
539     ((union xenkbd_out_event *)((char *)(page) + XENKBD_OUT_RING_OFFS))
540 #define XENKBD_OUT_RING_REF(page, idx) \
541     (XENKBD_OUT_RING((page))[(idx) % XENKBD_OUT_RING_LEN])
542 
543 struct xenkbd_page
544 {
545     uint32_t in_cons, in_prod;
546     uint32_t out_cons, out_prod;
547 };
548 
549 #endif /* __XEN_PUBLIC_IO_KBDIF_H__ */
550 
551 /*
552  * Local variables:
553  * mode: C
554  * c-file-style: "BSD"
555  * c-basic-offset: 4
556  * tab-width: 4
557  * indent-tabs-mode: nil
558  * End:
559  */
560