src/evdev.c

   1 /*
   2  * Copyright © 2010 Intel Corporation
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and
   5  * its documentation for any purpose is hereby granted without fee, provided
   6  * that the above copyright notice appear in all copies and that both that
   7  * copyright notice and this permission notice appear in supporting
   8  * documentation, and that the name of the copyright holders not be used in
   9  * advertising or publicity pertaining to distribution of the software
  10  * without specific, written prior permission.  The copyright holders make
  11  * no representations about the suitability of this software for any
  12  * purpose.  It is provided "as is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
  15  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  16  * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
  17  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  18  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
  19  * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  20  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  21  */
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <linux/input.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29
  30 #include "compositor.h"
  31 #include "evdev.h"
  32
  33 struct evdev_input {
  34         struct weston_input_device base;
  35         struct wl_list devices_list;
  36         struct udev_monitor *udev_monitor;
  37         char *seat_id;
  38 };
  39
  40 #define MAX_SLOTS 16
  41
  42 struct evdev_input_device {
  43         struct evdev_input *master;
  44         struct wl_list link;
  45         struct wl_event_source *source;
  46         struct weston_output *output;
  47         char *devnode;
  48         int fd;
  49         struct {
  50                 int min_x, max_x, min_y, max_y;
  51                 int old_x, old_y, reset_x, reset_y;
  52                 int32_t x, y;
  53         } abs;
  54
  55         struct {
  56                 int slot;
  57                 int32_t x[MAX_SLOTS];
  58                 int32_t y[MAX_SLOTS];
  59         } mt;
  60
  61         struct {
  62                 int dx, dy;
  63         } rel;
  64
  65         int type; /* event type flags */
  66
  67         int is_touchpad, is_mt;
  68 };
  69
  70 /* event type flags */
  71 #define EVDEV_ABSOLUTE_MOTION           (1 << 0)
  72 #define EVDEV_ABSOLUTE_MT_DOWN          (1 << 1)
  73 #define EVDEV_ABSOLUTE_MT_MOTION        (1 << 2)
  74 #define EVDEV_ABSOLUTE_MT_UP            (1 << 3)
  75 #define EVDEV_RELATIVE_MOTION           (1 << 4)
  76
  77 static inline void
  78 evdev_process_key(struct evdev_input_device *device,
  79                         struct input_event *e, int time)
  80 {
  81         if (e->value == 2)
  82                 return;
  83
  84         switch (e->code) {
  85         case BTN_TOOL_PEN:
  86         case BTN_TOOL_RUBBER:
  87         case BTN_TOOL_BRUSH:
  88         case BTN_TOOL_PENCIL:
  89         case BTN_TOOL_AIRBRUSH:
  90         case BTN_TOOL_FINGER:
  91         case BTN_TOOL_MOUSE:
  92         case BTN_TOOL_LENS:
  93                 if (device->is_touchpad)
  94                 {
  95                         device->abs.reset_x = 1;
  96                         device->abs.reset_y = 1;
  97                 }
  98                 break;
  99         case BTN_TOUCH:
 100                 /* Multitouch touchscreen devices might not send individually
 101                  * button events each time a new finger is down. So we don't
 102                  * send notification for such devices and we solve the button
 103                  * case emulating on compositor side. */
 104                 if (device->is_mt)
 105                         break;
 106
 107                 /* Treat BTN_TOUCH from devices that only have BTN_TOUCH as
 108                  * BTN_LEFT */
 109                 e->code = BTN_LEFT;
 110                 /* Intentional fallthrough! */
 111         case BTN_LEFT:
 112         case BTN_RIGHT:
 113         case BTN_MIDDLE:
 114         case BTN_SIDE:
 115         case BTN_EXTRA:
 116         case BTN_FORWARD:
 117         case BTN_BACK:
 118         case BTN_TASK:
 119                 notify_button(&device->master->base.input_device,
 120                               time, e->code, e->value);
 121                 break;
 122
 123         default:
 124                 notify_key(&device->master->base.input_device,
 125                            time, e->code, e->value);
 126                 break;
 127         }
 128 }
 129
 130 static void
 131 evdev_process_touch(struct evdev_input_device *device,
 132                     struct input_event *e)
 133 {
 134         const int screen_width = device->output->current->width;
 135         const int screen_height = device->output->current->height;
 136
 137         switch (e->code) {
 138         case ABS_MT_SLOT:
 139                 device->mt.slot = e->value;
 140                 break;
 141         case ABS_MT_TRACKING_ID:
 142                 if (e->value >= 0)
 143                         device->type |= EVDEV_ABSOLUTE_MT_DOWN;
 144                 else
 145                         device->type |= EVDEV_ABSOLUTE_MT_UP;
 146                 break;
 147         case ABS_MT_POSITION_X:
 148                 device->mt.x[device->mt.slot] =
 149                         (e->value - device->abs.min_x) * screen_width /
 150                         (device->abs.max_x - device->abs.min_x) +
 151                         device->output->x;
 152                 device->type |= EVDEV_ABSOLUTE_MT_MOTION;
 153                 break;
 154         case ABS_MT_POSITION_Y:
 155                 device->mt.y[device->mt.slot] =
 156                         (e->value - device->abs.min_y) * screen_height /
 157                         (device->abs.max_y - device->abs.min_y) +
 158                         device->output->y;
 159                 device->type |= EVDEV_ABSOLUTE_MT_MOTION;
 160                 break;
 161         }
 162 }
 163
 164 static inline void
 165 evdev_process_absolute_motion(struct evdev_input_device *device,
 166                               struct input_event *e)
 167 {
 168         const int screen_width = device->output->current->width;
 169         const int screen_height = device->output->current->height;
 170
 171         switch (e->code) {
 172         case ABS_X:
 173                 device->abs.x =
 174                         (e->value - device->abs.min_x) * screen_width /
 175                         (device->abs.max_x - device->abs.min_x) +
 176                         device->output->x;
 177                 device->type |= EVDEV_ABSOLUTE_MOTION;
 178                 break;
 179         case ABS_Y:
 180                 device->abs.y =
 181                         (e->value - device->abs.min_y) * screen_height /
 182                         (device->abs.max_y - device->abs.min_y) +
 183                         device->output->y;
 184                 device->type |= EVDEV_ABSOLUTE_MOTION;
 185                 break;
 186         }
 187 }
 188
 189 static inline void
 190 evdev_process_absolute_motion_touchpad(struct evdev_input_device *device,
 191                                        struct input_event *e)
 192 {
 193         /* FIXME: Make this configurable somehow. */
 194         const int touchpad_speed = 700;
 195
 196         switch (e->code) {
 197         case ABS_X:
 198                 e->value -= device->abs.min_x;
 199                 if (device->abs.reset_x)
 200                         device->abs.reset_x = 0;
 201                 else {
 202                         device->rel.dx =
 203                                 (e->value - device->abs.old_x) *
 204                                 touchpad_speed /
 205                                 (device->abs.max_x - device->abs.min_x);
 206                 }
 207                 device->abs.old_x = e->value;
 208                 device->type |= EVDEV_RELATIVE_MOTION;
 209                 break;
 210         case ABS_Y:
 211                 e->value -= device->abs.min_y;
 212                 if (device->abs.reset_y)
 213                         device->abs.reset_y = 0;
 214                 else {
 215                         device->rel.dy =
 216                                 (e->value - device->abs.old_y) *
 217                                 touchpad_speed /
 218                                 /* maybe use x size here to have the same scale? */
 219                                 (device->abs.max_y - device->abs.min_y);
 220                 }
 221                 device->abs.old_y = e->value;
 222                 device->type |= EVDEV_RELATIVE_MOTION;
 223                 break;
 224         }
 225 }
 226
 227 static inline void
 228 evdev_process_relative_motion(struct evdev_input_device *device,
 229                               struct input_event *e)
 230 {
 231         switch (e->code) {
 232         case REL_X:
 233                 device->rel.dx += e->value;
 234                 device->type |= EVDEV_RELATIVE_MOTION;
 235                 break;
 236         case REL_Y:
 237                 device->rel.dy += e->value;
 238                 device->type |= EVDEV_RELATIVE_MOTION;
 239                 break;
 240         }
 241 }
 242
 243 static inline void
 244 evdev_process_absolute(struct evdev_input_device *device,
 245                        struct input_event *e)
 246 {
 247         if (device->is_touchpad) {
 248                 evdev_process_absolute_motion_touchpad(device, e);
 249         } else if (device->is_mt) {
 250                 evdev_process_touch(device, e);
 251         } else {
 252                 evdev_process_absolute_motion(device, e);
 253         }
 254 }
 255
 256 static int
 257 is_motion_event(struct input_event *e)
 258 {
 259         switch (e->type) {
 260         case EV_REL:
 261                 switch (e->code) {
 262                 case REL_X:
 263                 case REL_Y:
 264                         return 1;
 265                 }
 266         case EV_ABS:
 267                 switch (e->code) {
 268                 case ABS_X:
 269                 case ABS_Y:
 270                 case ABS_MT_POSITION_X:
 271                 case ABS_MT_POSITION_Y:
 272                         return 1;
 273                 }
 274         }
 275
 276         return 0;
 277 }
 278
 279 static void
 280 evdev_flush_motion(struct evdev_input_device *device, uint32_t time)
 281 {
 282         struct wl_input_device *master = &device->master->base.input_device;
 283
 284         if (!device->type)
 285                 return;
 286
 287         if (device->type & EVDEV_RELATIVE_MOTION) {
 288                 notify_motion(master, time,
 289                               master->x + device->rel.dx,
 290                               master->y + device->rel.dy);
 291                 device->type &= ~EVDEV_RELATIVE_MOTION;
 292                 device->rel.dx = 0;
 293                 device->rel.dy = 0;
 294         }
 295         if (device->type & EVDEV_ABSOLUTE_MT_DOWN) {
 296                 notify_touch(master, time,
 297                              device->mt.slot,
 298                              device->mt.x[device->mt.slot],
 299                              device->mt.y[device->mt.slot],
 300                              WL_INPUT_DEVICE_TOUCH_DOWN);
 301                 device->type &= ~EVDEV_ABSOLUTE_MT_DOWN;
 302                 device->type &= ~EVDEV_ABSOLUTE_MT_MOTION;
 303         }
 304         if (device->type & EVDEV_ABSOLUTE_MT_MOTION) {
 305                 notify_touch(master, time,
 306                              device->mt.slot,
 307                              device->mt.x[device->mt.slot],
 308                              device->mt.y[device->mt.slot],
 309                              WL_INPUT_DEVICE_TOUCH_MOTION);
 310                 device->type &= ~EVDEV_ABSOLUTE_MT_DOWN;
 311                 device->type &= ~EVDEV_ABSOLUTE_MT_MOTION;
 312         }
 313         if (device->type & EVDEV_ABSOLUTE_MT_UP) {
 314                 notify_touch(master, time, device->mt.slot, 0, 0,
 315                              WL_INPUT_DEVICE_TOUCH_UP);
 316                 device->type &= ~EVDEV_ABSOLUTE_MT_UP;
 317         }
 318         if (device->type & EVDEV_ABSOLUTE_MOTION) {
 319                 notify_motion(master, time, device->abs.x, device->abs.y);
 320                 device->type &= ~EVDEV_ABSOLUTE_MOTION;
 321         }
 322 }
 323
 324 static int
 325 evdev_input_device_data(int fd, uint32_t mask, void *data)
 326 {
 327         struct weston_compositor *ec;
 328         struct evdev_input_device *device = data;
 329         struct input_event ev[8], *e, *end;
 330         int len;
 331         uint32_t time = 0;
 332
 333         ec = device->master->base.compositor;
 334         if (!ec->focus)
 335                 return 1;
 336
 337         len = read(fd, &ev, sizeof ev);
 338         if (len < 0 || len % sizeof e[0] != 0) {
 339                 /* FIXME: call device_removed when errno is ENODEV. */;
 340                 return 1;
 341         }
 342
 343         device->type = 0;
 344
 345         e = ev;
 346         end = (void *) ev + len;
 347         for (e = ev; e < end; e++) {
 348                 time = e->time.tv_sec * 1000 + e->time.tv_usec / 1000;
 349
 350                 /* we try to minimize the amount of notifications to be
 351                  * forwarded to the compositor, so we accumulate motion
 352                  * events and send as a bunch */
 353                 if (!is_motion_event(e))
 354                         evdev_flush_motion(device, time);
 355                 switch (e->type) {
 356                 case EV_REL:
 357                         evdev_process_relative_motion(device, e);
 358                         break;
 359                 case EV_ABS:
 360                         evdev_process_absolute(device, e);
 361                         break;
 362                 case EV_KEY:
 363                         evdev_process_key(device, e, time);
 364                         break;
 365                 }
 366         }
 367
 368         evdev_flush_motion(device, time);
 369
 370         return 1;
 371 }
 372
 373
 374 /* copied from udev/extras/input_id/input_id.c */
 375 /* we must use this kernel-compatible implementation */
 376 #define BITS_PER_LONG (sizeof(unsigned long) * 8)
 377 #define NBITS(x) ((((x)-1)/BITS_PER_LONG)+1)
 378 #define OFF(x)  ((x)%BITS_PER_LONG)
 379 #define BIT(x)  (1UL<<OFF(x))
 380 #define LONG(x) ((x)/BITS_PER_LONG)
 381 #define TEST_BIT(array, bit)    ((array[LONG(bit)] >> OFF(bit)) & 1)
 382 /* end copied */
 383
 384 static int
 385 evdev_configure_device(struct evdev_input_device *device)
 386 {
 387         struct input_absinfo absinfo;
 388         unsigned long ev_bits[NBITS(EV_MAX)];
 389         unsigned long abs_bits[NBITS(ABS_MAX)];
 390         unsigned long key_bits[NBITS(KEY_MAX)];
 391         int has_key, has_abs;
 392
 393         has_key = 0;
 394         has_abs = 0;
 395
 396         ioctl(device->fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits);
 397         if (TEST_BIT(ev_bits, EV_ABS)) {
 398                 has_abs = 1;
 399
 400                 ioctl(device->fd, EVIOCGBIT(EV_ABS, sizeof(abs_bits)),
 401                       abs_bits);
 402                 if (TEST_BIT(abs_bits, ABS_X)) {
 403                         ioctl(device->fd, EVIOCGABS(ABS_X), &absinfo);
 404                         device->abs.min_x = absinfo.minimum;
 405                         device->abs.max_x = absinfo.maximum;
 406                 }
 407                 if (TEST_BIT(abs_bits, ABS_Y)) {
 408                         ioctl(device->fd, EVIOCGABS(ABS_Y), &absinfo);
 409                         device->abs.min_y = absinfo.minimum;
 410                         device->abs.max_y = absinfo.maximum;
 411                 }
 412                 if (TEST_BIT(abs_bits, ABS_MT_SLOT)) {
 413                         device->is_mt = 1;
 414                         device->mt.slot = 0;
 415                 }
 416         }
 417         if (TEST_BIT(ev_bits, EV_KEY)) {
 418                 has_key = 1;
 419                 ioctl(device->fd, EVIOCGBIT(EV_KEY, sizeof(key_bits)),
 420                       key_bits);
 421                 if (TEST_BIT(key_bits, BTN_TOOL_FINGER) &&
 422                              !TEST_BIT(key_bits, BTN_TOOL_PEN))
 423                         device->is_touchpad = 1;
 424         }
 425
 426         /* This rule tries to catch accelerometer devices and opt out. We may
 427          * want to adjust the protocol later adding a proper event for dealing
 428          * with accelerometers and implement here accordingly */
 429         if (has_abs && !has_key)
 430                 return -1;
 431
 432         return 0;
 433 }
 434
 435 static struct evdev_input_device *
 436 evdev_input_device_create(struct evdev_input *master,
 437                           struct wl_display *display, const char *path)
 438 {
 439         struct evdev_input_device *device;
 440         struct weston_compositor *ec;
 441
 442         device = malloc(sizeof *device);
 443         if (device == NULL)
 444                 return NULL;
 445
 446         ec = master->base.compositor;
 447         device->output =
 448                 container_of(ec->output_list.next, struct weston_output, link);
 449
 450         device->master = master;
 451         device->is_touchpad = 0;
 452         device->is_mt = 0;
 453         device->devnode = strdup(path);
 454         device->mt.slot = -1;
 455         device->rel.dx = 0;
 456         device->rel.dy = 0;
 457
 458         device->fd = open(path, O_RDONLY);
 459         if (device->fd < 0)
 460                 goto err0;
 461
 462         if (evdev_configure_device(device) == -1)
 463                 goto err1;
 464
 465         device->source = wl_event_loop_add_fd(ec->input_loop, device->fd,
 466                                               WL_EVENT_READABLE,
 467                                               evdev_input_device_data, device);
 468         if (device->source == NULL)
 469                 goto err1;
 470
 471         wl_list_insert(master->devices_list.prev, &device->link);
 472
 473         return device;
 474
 475 err1:
 476         close(device->fd);
 477 err0:
 478         free(device->devnode);
 479         free(device);
 480         return NULL;
 481 }
 482
 483 static const char default_seat[] = "seat0";
 484
 485 static void
 486 device_added(struct udev_device *udev_device, struct evdev_input *master)
 487 {
 488         struct weston_compositor *c;
 489         const char *devnode;
 490         const char *device_seat;
 491
 492         device_seat = udev_device_get_property_value(udev_device, "ID_SEAT");
 493         if (!device_seat)
 494                 device_seat = default_seat;
 495
 496         if (strcmp(device_seat, master->seat_id))
 497                 return;
 498
 499         c = master->base.compositor;
 500         devnode = udev_device_get_devnode(udev_device);
 501         evdev_input_device_create(master, c->wl_display, devnode);
 502 }
 503
 504 static void
 505 device_removed(struct udev_device *udev_device, struct evdev_input *master)
 506 {
 507         const char *devnode = udev_device_get_devnode(udev_device);
 508         struct evdev_input_device *device, *next;
 509
 510         wl_list_for_each_safe(device, next, &master->devices_list, link) {
 511                 if (!strcmp(device->devnode, devnode)) {
 512                         wl_event_source_remove(device->source);
 513                         wl_list_remove(&device->link);
 514                         close(device->fd);
 515                         free(device->devnode);
 516                         free(device);
 517                         break;
 518                 }
 519         }
 520 }
 521
 522 void
 523 evdev_add_devices(struct udev *udev, struct weston_input_device *input_base)
 524 {
 525         struct evdev_input *input = (struct evdev_input *) input_base;
 526         struct udev_enumerate *e;
 527         struct udev_list_entry *entry;
 528         struct udev_device *device;
 529         const char *path;
 530
 531         e = udev_enumerate_new(udev);
 532         udev_enumerate_add_match_subsystem(e, "input");
 533         udev_enumerate_scan_devices(e);
 534         udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(e)) {
 535                 path = udev_list_entry_get_name(entry);
 536                 device = udev_device_new_from_syspath(udev, path);
 537
 538                 if (strncmp("event", udev_device_get_sysname(device), 5) != 0)
 539                         continue;
 540
 541                 device_added(device, input);
 542
 543                 udev_device_unref(device);
 544         }
 545         udev_enumerate_unref(e);
 546
 547         if (wl_list_empty(&input->devices_list)) {
 548                 fprintf(stderr,
 549                         "warning: no input devices on entering Weston. "
 550                         "Possible causes:\n"
 551                         "\t- no permissions to read /dev/input/event*\n"
 552                         "\t- seats misconfigured "
 553                         "(Weston backend option 'seat', "
 554                         "udev device property ID_SEAT)\n");
 555         }
 556 }
 557
 558 static int
 559 evdev_udev_handler(int fd, uint32_t mask, void *data)
 560 {
 561         struct evdev_input *master = data;
 562         struct udev_device *udev_device;
 563         const char *action;
 564
 565         udev_device = udev_monitor_receive_device(master->udev_monitor);
 566         if (!udev_device)
 567                 return 1;
 568
 569         action = udev_device_get_action(udev_device);
 570         if (action) {
 571                 if (strncmp("event", udev_device_get_sysname(udev_device), 5) != 0)
 572                         return 0;
 573
 574                 if (!strcmp(action, "add")) {
 575                         device_added(udev_device, master);
 576                 }
 577                 else if (!strcmp(action, "remove"))
 578                         device_removed(udev_device, master);
 579         }
 580         udev_device_unref(udev_device);
 581
 582         return 0;
 583 }
 584
 585 static int
 586 evdev_config_udev_monitor(struct udev *udev, struct evdev_input *master)
 587 {
 588         struct wl_event_loop *loop;
 589         struct weston_compositor *c = master->base.compositor;
 590
 591         master->udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
 592         if (!master->udev_monitor) {
 593                 fprintf(stderr, "udev: failed to create the udev monitor\n");
 594                 return 0;
 595         }
 596
 597         udev_monitor_filter_add_match_subsystem_devtype(master->udev_monitor,
 598                         "input", NULL);
 599
 600         if (udev_monitor_enable_receiving(master->udev_monitor)) {
 601                 fprintf(stderr, "udev: failed to bind the udev monitor\n");
 602                 return 0;
 603         }
 604
 605         loop = wl_display_get_event_loop(c->wl_display);
 606         wl_event_loop_add_fd(loop, udev_monitor_get_fd(master->udev_monitor),
 607                              WL_EVENT_READABLE, evdev_udev_handler, master);
 608
 609         return 1;
 610 }
 611
 612 void
 613 evdev_input_create(struct weston_compositor *c, struct udev *udev,
 614                    const char *seat)
 615 {
 616         struct evdev_input *input;
 617
 618         input = malloc(sizeof *input);
 619         if (input == NULL)
 620                 return;
 621
 622         memset(input, 0, sizeof *input);
 623         weston_input_device_init(&input->base, c);
 624
 625         wl_list_init(&input->devices_list);
 626         input->seat_id = strdup(seat);
 627         if (!evdev_config_udev_monitor(udev, input)) {
 628                 free(input->seat_id);
 629                 free(input);
 630                 return;
 631         }
 632
 633         evdev_add_devices(udev, &input->base);
 634
 635         c->input_device = &input->base.input_device;
 636 }
 637
 638 void
 639 evdev_remove_devices(struct weston_input_device *input_base)
 640 {
 641         struct evdev_input *input = (struct evdev_input *) input_base;
 642         struct evdev_input_device *device, *next;
 643
 644         wl_list_for_each_safe(device, next, &input->devices_list, link) {
 645                 wl_event_source_remove(device->source);
 646                 wl_list_remove(&device->link);
 647                 close(device->fd);
 648                 free(device->devnode);
 649                 free(device);
 650         }
 651 }
 652
 653 void
 654 evdev_input_destroy(struct weston_input_device *input_base)
 655 {
 656         struct evdev_input *input = (struct evdev_input *) input_base;
 657
 658         evdev_remove_devices(input_base);
 659         wl_list_remove(&input->base.link);
 660         free(input->seat_id);
 661         free(input);
 662 }