Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar...
[linux-2.6-microblaze.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         if (unlikely(!info->ptr))
67                 return;
68
69         input_report_rel(info->ptr, REL_X, motion->rel_x);
70         input_report_rel(info->ptr, REL_Y, motion->rel_y);
71         if (motion->rel_z)
72                 input_report_rel(info->ptr, REL_WHEEL, -motion->rel_z);
73         input_sync(info->ptr);
74 }
75
76 static void xenkbd_handle_position_event(struct xenkbd_info *info,
77                                          struct xenkbd_position *pos)
78 {
79         if (unlikely(!info->ptr))
80                 return;
81
82         input_report_abs(info->ptr, ABS_X, pos->abs_x);
83         input_report_abs(info->ptr, ABS_Y, pos->abs_y);
84         if (pos->rel_z)
85                 input_report_rel(info->ptr, REL_WHEEL, -pos->rel_z);
86         input_sync(info->ptr);
87 }
88
89 static void xenkbd_handle_key_event(struct xenkbd_info *info,
90                                     struct xenkbd_key *key)
91 {
92         struct input_dev *dev;
93         int value = key->pressed;
94
95         if (test_bit(key->keycode, info->ptr->keybit)) {
96                 dev = info->ptr;
97         } else if (test_bit(key->keycode, info->kbd->keybit)) {
98                 dev = info->kbd;
99                 if (key->pressed && test_bit(key->keycode, info->kbd->key))
100                         value = 2; /* Mark as autorepeat */
101         } else {
102                 pr_warn("unhandled keycode 0x%x\n", key->keycode);
103                 return;
104         }
105
106         if (unlikely(!dev))
107                 return;
108
109         input_event(dev, EV_KEY, key->keycode, value);
110         input_sync(dev);
111 }
112
113 static void xenkbd_handle_mt_event(struct xenkbd_info *info,
114                                    struct xenkbd_mtouch *mtouch)
115 {
116         if (unlikely(!info->mtouch))
117                 return;
118
119         if (mtouch->contact_id != info->mtouch_cur_contact_id) {
120                 info->mtouch_cur_contact_id = mtouch->contact_id;
121                 input_mt_slot(info->mtouch, mtouch->contact_id);
122         }
123
124         switch (mtouch->event_type) {
125         case XENKBD_MT_EV_DOWN:
126                 input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, true);
127                 /* fall through */
128
129         case XENKBD_MT_EV_MOTION:
130                 input_report_abs(info->mtouch, ABS_MT_POSITION_X,
131                                  mtouch->u.pos.abs_x);
132                 input_report_abs(info->mtouch, ABS_MT_POSITION_Y,
133                                  mtouch->u.pos.abs_y);
134                 break;
135
136         case XENKBD_MT_EV_SHAPE:
137                 input_report_abs(info->mtouch, ABS_MT_TOUCH_MAJOR,
138                                  mtouch->u.shape.major);
139                 input_report_abs(info->mtouch, ABS_MT_TOUCH_MINOR,
140                                  mtouch->u.shape.minor);
141                 break;
142
143         case XENKBD_MT_EV_ORIENT:
144                 input_report_abs(info->mtouch, ABS_MT_ORIENTATION,
145                                  mtouch->u.orientation);
146                 break;
147
148         case XENKBD_MT_EV_UP:
149                 input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, false);
150                 break;
151
152         case XENKBD_MT_EV_SYN:
153                 input_mt_sync_frame(info->mtouch);
154                 input_sync(info->mtouch);
155                 break;
156         }
157 }
158
159 static void xenkbd_handle_event(struct xenkbd_info *info,
160                                 union xenkbd_in_event *event)
161 {
162         switch (event->type) {
163         case XENKBD_TYPE_MOTION:
164                 xenkbd_handle_motion_event(info, &event->motion);
165                 break;
166
167         case XENKBD_TYPE_KEY:
168                 xenkbd_handle_key_event(info, &event->key);
169                 break;
170
171         case XENKBD_TYPE_POS:
172                 xenkbd_handle_position_event(info, &event->pos);
173                 break;
174
175         case XENKBD_TYPE_MTOUCH:
176                 xenkbd_handle_mt_event(info, &event->mtouch);
177                 break;
178         }
179 }
180
181 static irqreturn_t input_handler(int rq, void *dev_id)
182 {
183         struct xenkbd_info *info = dev_id;
184         struct xenkbd_page *page = info->page;
185         __u32 cons, prod;
186
187         prod = page->in_prod;
188         if (prod == page->in_cons)
189                 return IRQ_HANDLED;
190         rmb();                  /* ensure we see ring contents up to prod */
191         for (cons = page->in_cons; cons != prod; cons++)
192                 xenkbd_handle_event(info, &XENKBD_IN_RING_REF(page, cons));
193         mb();                   /* ensure we got ring contents */
194         page->in_cons = cons;
195         notify_remote_via_irq(info->irq);
196
197         return IRQ_HANDLED;
198 }
199
200 static int xenkbd_probe(struct xenbus_device *dev,
201                                   const struct xenbus_device_id *id)
202 {
203         int ret, i;
204         bool with_mtouch, with_kbd, with_ptr;
205         struct xenkbd_info *info;
206         struct input_dev *kbd, *ptr, *mtouch;
207
208         info = kzalloc(sizeof(*info), GFP_KERNEL);
209         if (!info) {
210                 xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
211                 return -ENOMEM;
212         }
213         dev_set_drvdata(&dev->dev, info);
214         info->xbdev = dev;
215         info->irq = -1;
216         info->gref = -1;
217         snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);
218
219         info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
220         if (!info->page)
221                 goto error_nomem;
222
223         /*
224          * The below are reverse logic, e.g. if the feature is set, then
225          * do not expose the corresponding virtual device.
226          */
227         with_kbd = !xenbus_read_unsigned(dev->otherend,
228                                          XENKBD_FIELD_FEAT_DSBL_KEYBRD, 0);
229
230         with_ptr = !xenbus_read_unsigned(dev->otherend,
231                                          XENKBD_FIELD_FEAT_DSBL_POINTER, 0);
232
233         /* Direct logic: if set, then create multi-touch device. */
234         with_mtouch = xenbus_read_unsigned(dev->otherend,
235                                            XENKBD_FIELD_FEAT_MTOUCH, 0);
236         if (with_mtouch) {
237                 ret = xenbus_write(XBT_NIL, dev->nodename,
238                                    XENKBD_FIELD_REQ_MTOUCH, "1");
239                 if (ret) {
240                         pr_warn("xenkbd: can't request multi-touch");
241                         with_mtouch = 0;
242                 }
243         }
244
245         /* keyboard */
246         if (with_kbd) {
247                 kbd = input_allocate_device();
248                 if (!kbd)
249                         goto error_nomem;
250                 kbd->name = "Xen Virtual Keyboard";
251                 kbd->phys = info->phys;
252                 kbd->id.bustype = BUS_PCI;
253                 kbd->id.vendor = 0x5853;
254                 kbd->id.product = 0xffff;
255
256                 __set_bit(EV_KEY, kbd->evbit);
257                 for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
258                         __set_bit(i, kbd->keybit);
259                 for (i = KEY_OK; i < KEY_MAX; i++)
260                         __set_bit(i, kbd->keybit);
261
262                 ret = input_register_device(kbd);
263                 if (ret) {
264                         input_free_device(kbd);
265                         xenbus_dev_fatal(dev, ret,
266                                          "input_register_device(kbd)");
267                         goto error;
268                 }
269                 info->kbd = kbd;
270         }
271
272         /* pointing device */
273         if (with_ptr) {
274                 unsigned int abs;
275
276                 /* Set input abs params to match backend screen res */
277                 abs = xenbus_read_unsigned(dev->otherend,
278                                            XENKBD_FIELD_FEAT_ABS_POINTER, 0);
279                 ptr_size[KPARAM_X] = xenbus_read_unsigned(dev->otherend,
280                                                           XENKBD_FIELD_WIDTH,
281                                                           ptr_size[KPARAM_X]);
282                 ptr_size[KPARAM_Y] = xenbus_read_unsigned(dev->otherend,
283                                                           XENKBD_FIELD_HEIGHT,
284                                                           ptr_size[KPARAM_Y]);
285                 if (abs) {
286                         ret = xenbus_write(XBT_NIL, dev->nodename,
287                                            XENKBD_FIELD_REQ_ABS_POINTER, "1");
288                         if (ret) {
289                                 pr_warn("xenkbd: can't request abs-pointer\n");
290                                 abs = 0;
291                         }
292                 }
293
294                 ptr = input_allocate_device();
295                 if (!ptr)
296                         goto error_nomem;
297                 ptr->name = "Xen Virtual Pointer";
298                 ptr->phys = info->phys;
299                 ptr->id.bustype = BUS_PCI;
300                 ptr->id.vendor = 0x5853;
301                 ptr->id.product = 0xfffe;
302
303                 if (abs) {
304                         __set_bit(EV_ABS, ptr->evbit);
305                         input_set_abs_params(ptr, ABS_X, 0,
306                                              ptr_size[KPARAM_X], 0, 0);
307                         input_set_abs_params(ptr, ABS_Y, 0,
308                                              ptr_size[KPARAM_Y], 0, 0);
309                 } else {
310                         input_set_capability(ptr, EV_REL, REL_X);
311                         input_set_capability(ptr, EV_REL, REL_Y);
312                 }
313                 input_set_capability(ptr, EV_REL, REL_WHEEL);
314
315                 __set_bit(EV_KEY, ptr->evbit);
316                 for (i = BTN_LEFT; i <= BTN_TASK; i++)
317                         __set_bit(i, ptr->keybit);
318
319                 ret = input_register_device(ptr);
320                 if (ret) {
321                         input_free_device(ptr);
322                         xenbus_dev_fatal(dev, ret,
323                                          "input_register_device(ptr)");
324                         goto error;
325                 }
326                 info->ptr = ptr;
327         }
328
329         /* multi-touch device */
330         if (with_mtouch) {
331                 int num_cont, width, height;
332
333                 mtouch = input_allocate_device();
334                 if (!mtouch)
335                         goto error_nomem;
336
337                 num_cont = xenbus_read_unsigned(info->xbdev->otherend,
338                                                 XENKBD_FIELD_MT_NUM_CONTACTS,
339                                                 1);
340                 width = xenbus_read_unsigned(info->xbdev->otherend,
341                                              XENKBD_FIELD_MT_WIDTH,
342                                              XENFB_WIDTH);
343                 height = xenbus_read_unsigned(info->xbdev->otherend,
344                                               XENKBD_FIELD_MT_HEIGHT,
345                                               XENFB_HEIGHT);
346
347                 mtouch->name = "Xen Virtual Multi-touch";
348                 mtouch->phys = info->phys;
349                 mtouch->id.bustype = BUS_PCI;
350                 mtouch->id.vendor = 0x5853;
351                 mtouch->id.product = 0xfffd;
352
353                 input_set_abs_params(mtouch, ABS_MT_TOUCH_MAJOR,
354                                      0, 255, 0, 0);
355                 input_set_abs_params(mtouch, ABS_MT_POSITION_X,
356                                      0, width, 0, 0);
357                 input_set_abs_params(mtouch, ABS_MT_POSITION_Y,
358                                      0, height, 0, 0);
359
360                 ret = input_mt_init_slots(mtouch, num_cont, INPUT_MT_DIRECT);
361                 if (ret) {
362                         input_free_device(mtouch);
363                         xenbus_dev_fatal(info->xbdev, ret,
364                                          "input_mt_init_slots");
365                         goto error;
366                 }
367
368                 ret = input_register_device(mtouch);
369                 if (ret) {
370                         input_free_device(mtouch);
371                         xenbus_dev_fatal(info->xbdev, ret,
372                                          "input_register_device(mtouch)");
373                         goto error;
374                 }
375                 info->mtouch_cur_contact_id = -1;
376                 info->mtouch = mtouch;
377         }
378
379         if (!(with_kbd || with_ptr || with_mtouch)) {
380                 ret = -ENXIO;
381                 goto error;
382         }
383
384         ret = xenkbd_connect_backend(dev, info);
385         if (ret < 0)
386                 goto error;
387
388         return 0;
389
390  error_nomem:
391         ret = -ENOMEM;
392         xenbus_dev_fatal(dev, ret, "allocating device memory");
393  error:
394         xenkbd_remove(dev);
395         return ret;
396 }
397
398 static int xenkbd_resume(struct xenbus_device *dev)
399 {
400         struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
401
402         xenkbd_disconnect_backend(info);
403         memset(info->page, 0, PAGE_SIZE);
404         return xenkbd_connect_backend(dev, info);
405 }
406
407 static int xenkbd_remove(struct xenbus_device *dev)
408 {
409         struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
410
411         xenkbd_disconnect_backend(info);
412         if (info->kbd)
413                 input_unregister_device(info->kbd);
414         if (info->ptr)
415                 input_unregister_device(info->ptr);
416         if (info->mtouch)
417                 input_unregister_device(info->mtouch);
418         free_page((unsigned long)info->page);
419         kfree(info);
420         return 0;
421 }
422
423 static int xenkbd_connect_backend(struct xenbus_device *dev,
424                                   struct xenkbd_info *info)
425 {
426         int ret, evtchn;
427         struct xenbus_transaction xbt;
428
429         ret = gnttab_grant_foreign_access(dev->otherend_id,
430                                           virt_to_gfn(info->page), 0);
431         if (ret < 0)
432                 return ret;
433         info->gref = ret;
434
435         ret = xenbus_alloc_evtchn(dev, &evtchn);
436         if (ret)
437                 goto error_grant;
438         ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
439                                         0, dev->devicetype, info);
440         if (ret < 0) {
441                 xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
442                 goto error_evtchan;
443         }
444         info->irq = ret;
445
446  again:
447         ret = xenbus_transaction_start(&xbt);
448         if (ret) {
449                 xenbus_dev_fatal(dev, ret, "starting transaction");
450                 goto error_irqh;
451         }
452         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_REF, "%lu",
453                             virt_to_gfn(info->page));
454         if (ret)
455                 goto error_xenbus;
456         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_GREF,
457                             "%u", info->gref);
458         if (ret)
459                 goto error_xenbus;
460         ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_EVT_CHANNEL, "%u",
461                             evtchn);
462         if (ret)
463                 goto error_xenbus;
464         ret = xenbus_transaction_end(xbt, 0);
465         if (ret) {
466                 if (ret == -EAGAIN)
467                         goto again;
468                 xenbus_dev_fatal(dev, ret, "completing transaction");
469                 goto error_irqh;
470         }
471
472         xenbus_switch_state(dev, XenbusStateInitialised);
473         return 0;
474
475  error_xenbus:
476         xenbus_transaction_end(xbt, 1);
477         xenbus_dev_fatal(dev, ret, "writing xenstore");
478  error_irqh:
479         unbind_from_irqhandler(info->irq, info);
480         info->irq = -1;
481  error_evtchan:
482         xenbus_free_evtchn(dev, evtchn);
483  error_grant:
484         gnttab_end_foreign_access(info->gref, 0, 0UL);
485         info->gref = -1;
486         return ret;
487 }
488
489 static void xenkbd_disconnect_backend(struct xenkbd_info *info)
490 {
491         if (info->irq >= 0)
492                 unbind_from_irqhandler(info->irq, info);
493         info->irq = -1;
494         if (info->gref >= 0)
495                 gnttab_end_foreign_access(info->gref, 0, 0UL);
496         info->gref = -1;
497 }
498
499 static void xenkbd_backend_changed(struct xenbus_device *dev,
500                                    enum xenbus_state backend_state)
501 {
502         switch (backend_state) {
503         case XenbusStateInitialising:
504         case XenbusStateInitialised:
505         case XenbusStateReconfiguring:
506         case XenbusStateReconfigured:
507         case XenbusStateUnknown:
508                 break;
509
510         case XenbusStateInitWait:
511                 xenbus_switch_state(dev, XenbusStateConnected);
512                 break;
513
514         case XenbusStateConnected:
515                 /*
516                  * Work around xenbus race condition: If backend goes
517                  * through InitWait to Connected fast enough, we can
518                  * get Connected twice here.
519                  */
520                 if (dev->state != XenbusStateConnected)
521                         xenbus_switch_state(dev, XenbusStateConnected);
522                 break;
523
524         case XenbusStateClosed:
525                 if (dev->state == XenbusStateClosed)
526                         break;
527                 /* fall through - Missed the backend's CLOSING state */
528         case XenbusStateClosing:
529                 xenbus_frontend_closed(dev);
530                 break;
531         }
532 }
533
534 static const struct xenbus_device_id xenkbd_ids[] = {
535         { XENKBD_DRIVER_NAME },
536         { "" }
537 };
538
539 static struct xenbus_driver xenkbd_driver = {
540         .ids = xenkbd_ids,
541         .probe = xenkbd_probe,
542         .remove = xenkbd_remove,
543         .resume = xenkbd_resume,
544         .otherend_changed = xenkbd_backend_changed,
545 };
546
547 static int __init xenkbd_init(void)
548 {
549         if (!xen_domain())
550                 return -ENODEV;
551
552         /* Nothing to do if running in dom0. */
553         if (xen_initial_domain())
554                 return -ENODEV;
555
556         if (!xen_has_pv_devices())
557                 return -ENODEV;
558
559         return xenbus_register_frontend(&xenkbd_driver);
560 }
561
562 static void __exit xenkbd_cleanup(void)
563 {
564         xenbus_unregister_driver(&xenkbd_driver);
565 }
566
567 module_init(xenkbd_init);
568 module_exit(xenkbd_cleanup);
569
570 MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
571 MODULE_LICENSE("GPL");
572 MODULE_ALIAS("xen:" XENKBD_DRIVER_NAME);