6bf56bb5f8d97dd4b5835e54c7e7ca764db98434
[muen/linux.git] / drivers / input / misc / xen-kbdfront.c
1 /*
2  * Xen para-virtual input device
3  *
4  * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
5  * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
6  *
7  *  Based on linux/drivers/input/mouse/sermouse.c
8  *
9  *  This file is subject to the terms and conditions of the GNU General Public
10  *  License. See the file COPYING in the main directory of this archive for
11  *  more details.
12  */
13
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/module.h>
19 #include <linux/input.h>
20 #include <linux/input/mt.h>
21 #include <linux/slab.h>
22
23 #include <asm/xen/hypervisor.h>
24
25 #include <xen/xen.h>
26 #include <xen/events.h>
27 #include <xen/page.h>
28 #include <xen/grant_table.h>
29 #include <xen/interface/grant_table.h>
30 #include <xen/interface/io/fbif.h>
31 #include <xen/interface/io/kbdif.h>
32 #include <xen/xenbus.h>
33 #include <xen/platform_pci.h>
34
35 struct xenkbd_info {
36         struct input_dev *kbd;
37         struct input_dev *ptr;
38         struct input_dev *mtouch;
39         struct xenkbd_page *page;
40         int gref;
41         int irq;
42         struct xenbus_device *xbdev;
43         char phys[32];
44         /* current MT slot/contact ID we are injecting events in */
45         int mtouch_cur_contact_id;
46 };
47
48 enum { KPARAM_X, KPARAM_Y, KPARAM_CNT };
49 static int ptr_size[KPARAM_CNT] = { XENFB_WIDTH, XENFB_HEIGHT };
50 module_param_array(ptr_size, int, NULL, 0444);
51 MODULE_PARM_DESC(ptr_size,
52         "Pointing device width, height in pixels (default 800,600)");
53
54 static int xenkbd_remove(struct xenbus_device *);
55 static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *);
56 static void xenkbd_disconnect_backend(struct xenkbd_info *);
57
58 /*
59  * Note: if you need to send out events, see xenfb_do_update() for how
60  * to do that.
61  */
62
63 static void xenkbd_handle_motion_event(struct xenkbd_info *info,
64                                        struct xenkbd_motion *motion)
65 {
66         input_report_rel(info->ptr, REL_X, motion->rel_x);
67         input_report_rel(info->ptr, REL_Y, motion->rel_y);
68         if (motion->rel_z)
69                 input_report_rel(info->ptr, REL_WHEEL, -motion->rel_z);
70         input_sync(info->ptr);
71 }
72
73 static void xenkbd_handle_position_event(struct xenkbd_info *info,
74                                          struct xenkbd_position *pos)
75 {
76         input_report_abs(info->ptr, ABS_X, pos->abs_x);
77         input_report_abs(info->ptr, ABS_Y, pos->abs_y);
78         if (pos->rel_z)
79                 input_report_rel(info->ptr, REL_WHEEL, -pos->rel_z);
80         input_sync(info->ptr);
81 }
82
83 static void xenkbd_handle_key_event(struct xenkbd_info *info,
84                                     struct xenkbd_key *key)
85 {
86         struct input_dev *dev;
87         int value = key->pressed;
88
89         if (test_bit(key->keycode, info->ptr->keybit)) {
90                 dev = info->ptr;
91         } else if (test_bit(key->keycode, info->kbd->keybit)) {
92                 dev = info->kbd;
93                 if (key->pressed && test_bit(key->keycode, info->kbd->key))
94                         value = 2; /* Mark as autorepeat */
95         } else {
96                 pr_warn("unhandled keycode 0x%x\n", key->keycode);
97                 return;
98         }
99
100         input_event(dev, EV_KEY, key->keycode, value);
101         input_sync(dev);
102 }
103
104 static void xenkbd_handle_mt_event(struct xenkbd_info *info,
105                                    struct xenkbd_mtouch *mtouch)
106 {
107         if (unlikely(!info->mtouch))
108                 return;
109
110         if (mtouch->contact_id != info->mtouch_cur_contact_id) {
111                 info->mtouch_cur_contact_id = mtouch->contact_id;
112                 input_mt_slot(info->mtouch, mtouch->contact_id);
113         }
114
115         switch (mtouch->event_type) {
116         case XENKBD_MT_EV_DOWN:
117                 input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, true);
118                 /* fall through */
119
120         case XENKBD_MT_EV_MOTION:
121                 input_report_abs(info->mtouch, ABS_MT_POSITION_X,
122                                  mtouch->u.pos.abs_x);
123                 input_report_abs(info->mtouch, ABS_MT_POSITION_Y,
124                                  mtouch->u.pos.abs_y);
125                 break;
126
127         case XENKBD_MT_EV_SHAPE:
128                 input_report_abs(info->mtouch, ABS_MT_TOUCH_MAJOR,
129                                  mtouch->u.shape.major);
130                 input_report_abs(info->mtouch, ABS_MT_TOUCH_MINOR,
131                                  mtouch->u.shape.minor);
132                 break;
133
134         case XENKBD_MT_EV_ORIENT:
135                 input_report_abs(info->mtouch, ABS_MT_ORIENTATION,
136                                  mtouch->u.orientation);
137                 break;
138
139         case XENKBD_MT_EV_UP:
140                 input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, false);
141                 break;
142
143         case XENKBD_MT_EV_SYN:
144                 input_mt_sync_frame(info->mtouch);
145                 input_sync(info->mtouch);
146                 break;
147         }
148 }
149
150 static void xenkbd_handle_event(struct xenkbd_info *info,
151                                 union xenkbd_in_event *event)
152 {
153         switch (event->type) {
154         case XENKBD_TYPE_MOTION:
155                 xenkbd_handle_motion_event(info, &event->motion);
156                 break;
157
158         case XENKBD_TYPE_KEY:
159                 xenkbd_handle_key_event(info, &event->key);
160                 break;
161
162         case XENKBD_TYPE_POS:
163                 xenkbd_handle_position_event(info, &event->pos);
164                 break;
165
166         case XENKBD_TYPE_MTOUCH:
167                 xenkbd_handle_mt_event(info, &event->mtouch);
168                 break;
169         }
170 }
171
172 static irqreturn_t input_handler(int rq, void *dev_id)
173 {
174         struct xenkbd_info *info = dev_id;
175         struct xenkbd_page *page = info->page;
176         __u32 cons, prod;
177
178         prod = page->in_prod;
179         if (prod == page->in_cons)
180                 return IRQ_HANDLED;
181         rmb();                  /* ensure we see ring contents up to prod */
182         for (cons = page->in_cons; cons != prod; cons++)
183                 xenkbd_handle_event(info, &XENKBD_IN_RING_REF(page, cons));
184         mb();                   /* ensure we got ring contents */
185         page->in_cons = cons;
186         notify_remote_via_irq(info->irq);
187
188         return IRQ_HANDLED;
189 }
190
191 static int xenkbd_probe(struct xenbus_device *dev,
192                                   const struct xenbus_device_id *id)
193 {
194         int ret, i;
195         unsigned int abs, touch;
196         struct xenkbd_info *info;
197         struct input_dev *kbd, *ptr, *mtouch;
198
199         info = kzalloc(sizeof(*info), GFP_KERNEL);
200         if (!info) {
201                 xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
202                 return -ENOMEM;
203         }
204         dev_set_drvdata(&dev->dev, info);
205         info->xbdev = dev;
206         info->irq = -1;
207         info->gref = -1;
208         snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);
209
210         info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
211         if (!info->page)
212                 goto error_nomem;
213
214         /* Set input abs params to match backend screen res */
215         abs = xenbus_read_unsigned(dev->otherend,
216                                    XENKBD_FIELD_FEAT_ABS_POINTER, 0);
217         ptr_size[KPARAM_X] = xenbus_read_unsigned(dev->otherend,
218                                                   XENKBD_FIELD_WIDTH,
219                                                   ptr_size[KPARAM_X]);
220         ptr_size[KPARAM_Y] = xenbus_read_unsigned(dev->otherend,
221                                                   XENKBD_FIELD_HEIGHT,
222                                                   ptr_size[KPARAM_Y]);
223         if (abs) {
224                 ret = xenbus_write(XBT_NIL, dev->nodename,
225                                    XENKBD_FIELD_REQ_ABS_POINTER, "1");
226                 if (ret) {
227                         pr_warn("xenkbd: can't request abs-pointer\n");
228                         abs = 0;
229                 }
230         }
231
232         touch = xenbus_read_unsigned(dev->nodename,
233                                      XENKBD_FIELD_FEAT_MTOUCH, 0);
234         if (touch) {
235                 ret = xenbus_write(XBT_NIL, dev->nodename,
236                                    XENKBD_FIELD_REQ_MTOUCH, "1");
237                 if (ret) {
238                         pr_warn("xenkbd: can't request multi-touch");
239                         touch = 0;
240                 }
241         }
242
243         /* keyboard */
244         kbd = input_allocate_device();
245         if (!kbd)
246                 goto error_nomem;
247         kbd->name = "Xen Virtual Keyboard";
248         kbd->phys = info->phys;
249         kbd->id.bustype = BUS_PCI;
250         kbd->id.vendor = 0x5853;
251         kbd->id.product = 0xffff;
252
253         __set_bit(EV_KEY, kbd->evbit);
254         for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
255                 __set_bit(i, kbd->keybit);
256         for (i = KEY_OK; i < KEY_MAX; i++)
257                 __set_bit(i, kbd->keybit);
258
259         ret = input_register_device(kbd);
260         if (ret) {
261                 input_free_device(kbd);
262                 xenbus_dev_fatal(dev, ret, "input_register_device(kbd)");
263                 goto error;
264         }
265         info->kbd = kbd;
266
267         /* pointing device */
268         ptr = input_allocate_device();
269         if (!ptr)
270                 goto error_nomem;
271         ptr->name = "Xen Virtual Pointer";
272         ptr->phys = info->phys;
273         ptr->id.bustype = BUS_PCI;
274         ptr->id.vendor = 0x5853;
275         ptr->id.product = 0xfffe;
276
277         if (abs) {
278                 __set_bit(EV_ABS, ptr->evbit);
279                 input_set_abs_params(ptr, ABS_X, 0, ptr_size[KPARAM_X], 0, 0);
280                 input_set_abs_params(ptr, ABS_Y, 0, ptr_size[KPARAM_Y], 0, 0);
281         } else {
282                 input_set_capability(ptr, EV_REL, REL_X);
283                 input_set_capability(ptr, EV_REL, REL_Y);
284         }
285         input_set_capability(ptr, EV_REL, REL_WHEEL);
286
287         __set_bit(EV_KEY, ptr->evbit);
288         for (i = BTN_LEFT; i <= BTN_TASK; i++)
289                 __set_bit(i, ptr->keybit);
290
291         ret = input_register_device(ptr);
292         if (ret) {
293                 input_free_device(ptr);
294                 xenbus_dev_fatal(dev, ret, "input_register_device(ptr)");
295                 goto error;
296         }
297         info->ptr = ptr;
298
299         /* multi-touch device */
300         if (touch) {
301                 int num_cont, width, height;
302
303                 mtouch = input_allocate_device();
304                 if (!mtouch)
305                         goto error_nomem;
306
307                 num_cont = xenbus_read_unsigned(info->xbdev->nodename,
308                                                 XENKBD_FIELD_MT_NUM_CONTACTS,
309                                                 1);
310                 width = xenbus_read_unsigned(info->xbdev->nodename,
311                                              XENKBD_FIELD_MT_WIDTH,
312                                              XENFB_WIDTH);
313                 height = xenbus_read_unsigned(info->xbdev->nodename,
314                                               XENKBD_FIELD_MT_HEIGHT,
315                                               XENFB_HEIGHT);
316
317                 mtouch->name = "Xen Virtual Multi-touch";
318                 mtouch->phys = info->phys;
319                 mtouch->id.bustype = BUS_PCI;
320                 mtouch->id.vendor = 0x5853;
321                 mtouch->id.product = 0xfffd;
322
323                 input_set_abs_params(mtouch, ABS_MT_TOUCH_MAJOR,
324                                      0, 255, 0, 0);
325                 input_set_abs_params(mtouch, ABS_MT_POSITION_X,
326                                      0, width, 0, 0);
327                 input_set_abs_params(mtouch, ABS_MT_POSITION_Y,
328                                      0, height, 0, 0);
329                 input_set_abs_params(mtouch, ABS_MT_PRESSURE,
330                                      0, 255, 0, 0);
331
332                 ret = input_mt_init_slots(mtouch, num_cont, INPUT_MT_DIRECT);
333                 if (ret) {
334                         input_free_device(mtouch);
335                         xenbus_dev_fatal(info->xbdev, ret,
336                                          "input_mt_init_slots");
337                         goto error;
338                 }
339
340                 ret = input_register_device(mtouch);
341                 if (ret) {
342                         input_free_device(mtouch);
343                         xenbus_dev_fatal(info->xbdev, ret,
344                                          "input_register_device(mtouch)");
345                         goto error;
346                 }
347                 info->mtouch_cur_contact_id = -1;
348                 info->mtouch = mtouch;
349         }
350
351         ret = xenkbd_connect_backend(dev, info);
352         if (ret < 0)
353                 goto error;
354
355         return 0;
356
357  error_nomem:
358         ret = -ENOMEM;
359         xenbus_dev_fatal(dev, ret, "allocating device memory");
360  error:
361         xenkbd_remove(dev);
362         return ret;
363 }
364
365 static int xenkbd_resume(struct xenbus_device *dev)
366 {
367         struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
368
369         xenkbd_disconnect_backend(info);
370         memset(info->page, 0, PAGE_SIZE);
371         return xenkbd_connect_backend(dev, info);
372 }
373
374 static int xenkbd_remove(struct xenbus_device *dev)
375 {
376         struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
377
378         xenkbd_disconnect_backend(info);
379         if (info->kbd)
380                 input_unregister_device(info->kbd);
381         if (info->ptr)
382                 input_unregister_device(info->ptr);
383         if (info->mtouch)
384                 input_unregister_device(info->mtouch);
385         free_page((unsigned long)info->page);
386         kfree(info);
387         return 0;
388 }
389
390 static int xenkbd_connect_backend(struct xenbus_device *dev,
391                                   struct xenkbd_info *info)
392 {
393         int ret, evtchn;
394         struct xenbus_transaction xbt;
395
396         ret = gnttab_grant_foreign_access(dev->otherend_id,
397                                           virt_to_gfn(info->page), 0);
398         if (ret < 0)
399                 return ret;
400         info->gref = ret;
401
402         ret = xenbus_alloc_evtchn(dev, &evtchn);
403         if (ret)
404                 goto error_grant;
405         ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
406                                         0, dev->devicetype, info);
407         if (ret < 0) {
408                 xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
409                 goto error_evtchan;
410         }
411         info->irq = ret;
412
413  again:
414         ret = xenbus_transaction_start(&xbt);
415         if (ret) {
416                 xenbus_dev_fatal(dev, ret, "starting transaction");
417                 goto error_irqh;
418         }
419         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_REF, "%lu",
420                             virt_to_gfn(info->page));
421         if (ret)
422                 goto error_xenbus;
423         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_GREF,
424                             "%u", info->gref);
425         if (ret)
426                 goto error_xenbus;
427         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_EVT_CHANNEL, "%u",
428                             evtchn);
429         if (ret)
430                 goto error_xenbus;
431         ret = xenbus_transaction_end(xbt, 0);
432         if (ret) {
433                 if (ret == -EAGAIN)
434                         goto again;
435                 xenbus_dev_fatal(dev, ret, "completing transaction");
436                 goto error_irqh;
437         }
438
439         xenbus_switch_state(dev, XenbusStateInitialised);
440         return 0;
441
442  error_xenbus:
443         xenbus_transaction_end(xbt, 1);
444         xenbus_dev_fatal(dev, ret, "writing xenstore");
445  error_irqh:
446         unbind_from_irqhandler(info->irq, info);
447         info->irq = -1;
448  error_evtchan:
449         xenbus_free_evtchn(dev, evtchn);
450  error_grant:
451         gnttab_end_foreign_access(info->gref, 0, 0UL);
452         info->gref = -1;
453         return ret;
454 }
455
456 static void xenkbd_disconnect_backend(struct xenkbd_info *info)
457 {
458         if (info->irq >= 0)
459                 unbind_from_irqhandler(info->irq, info);
460         info->irq = -1;
461         if (info->gref >= 0)
462                 gnttab_end_foreign_access(info->gref, 0, 0UL);
463         info->gref = -1;
464 }
465
466 static void xenkbd_backend_changed(struct xenbus_device *dev,
467                                    enum xenbus_state backend_state)
468 {
469         switch (backend_state) {
470         case XenbusStateInitialising:
471         case XenbusStateInitialised:
472         case XenbusStateReconfiguring:
473         case XenbusStateReconfigured:
474         case XenbusStateUnknown:
475                 break;
476
477         case XenbusStateInitWait:
478                 xenbus_switch_state(dev, XenbusStateConnected);
479                 break;
480
481         case XenbusStateConnected:
482                 /*
483                  * Work around xenbus race condition: If backend goes
484                  * through InitWait to Connected fast enough, we can
485                  * get Connected twice here.
486                  */
487                 if (dev->state != XenbusStateConnected)
488                         xenbus_switch_state(dev, XenbusStateConnected);
489                 break;
490
491         case XenbusStateClosed:
492                 if (dev->state == XenbusStateClosed)
493                         break;
494                 /* Missed the backend's CLOSING state -- fallthrough */
495         case XenbusStateClosing:
496                 xenbus_frontend_closed(dev);
497                 break;
498         }
499 }
500
501 static const struct xenbus_device_id xenkbd_ids[] = {
502         { XENKBD_DRIVER_NAME },
503         { "" }
504 };
505
506 static struct xenbus_driver xenkbd_driver = {
507         .ids = xenkbd_ids,
508         .probe = xenkbd_probe,
509         .remove = xenkbd_remove,
510         .resume = xenkbd_resume,
511         .otherend_changed = xenkbd_backend_changed,
512 };
513
514 static int __init xenkbd_init(void)
515 {
516         if (!xen_domain())
517                 return -ENODEV;
518
519         /* Nothing to do if running in dom0. */
520         if (xen_initial_domain())
521                 return -ENODEV;
522
523         if (!xen_has_pv_devices())
524                 return -ENODEV;
525
526         return xenbus_register_frontend(&xenkbd_driver);
527 }
528
529 static void __exit xenkbd_cleanup(void)
530 {
531         xenbus_unregister_driver(&xenkbd_driver);
532 }
533
534 module_init(xenkbd_init);
535 module_exit(xenkbd_cleanup);
536
537 MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
538 MODULE_LICENSE("GPL");
539 MODULE_ALIAS("xen:" XENKBD_DRIVER_NAME);