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 #define _GNU_SOURCE
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <linux/input.h>
  29 #include <unistd.h>
  30 #include <fcntl.h>
  31
  32 #include "compositor.h"
  33 #include "evdev.h"
  34
  35 struct evdev_input {
  36         struct weston_input_device base;
  37         struct wl_list devices_list;
  38         struct udev_monitor *udev_monitor;
  39         char *seat_id;
  40 };
  41
  42 #define MAX_SLOTS 16
  43
  44 struct evdev_input_device {
  45         struct evdev_input *master;
  46         struct wl_list link;
  47         struct wl_event_source *source;
  48         struct weston_output *output;
  49         char *devnode;
  50         int fd;
  51         struct {
  52                 int min_x, max_x, min_y, max_y;
  53                 int old_x, old_y, reset_x, reset_y;
  54                 int32_t x, y;
  55         } abs;
  56
  57         struct {
  58                 int slot;
  59                 int32_t x[MAX_SLOTS];
  60                 int32_t y[MAX_SLOTS];
  61         } mt;
  62
  63         struct {
  64                 int dx, dy;
  65         } rel;
  66
  67         int type; /* event type flags */
  68
  69         int is_touchpad, is_mt;
  70 };
  71
  72 /* event type flags */
  73 #define EVDEV_ABSOLUTE_MOTION           (1 << 0)
  74 #define EVDEV_ABSOLUTE_MT_DOWN          (1 << 1)
  75 #define EVDEV_ABSOLUTE_MT_MOTION        (1 << 2)
  76 #define EVDEV_ABSOLUTE_MT_UP            (1 << 3)
  77 #define EVDEV_RELATIVE_MOTION           (1 << 4)
  78
  79 static inline void
  80 evdev_process_key(struct evdev_input_device *device,
  81                         struct input_event *e, int time)
  82 {
  83         if (e->value == 2)
  84                 return;
  85
  86         switch (e->code) {
  87         case BTN_TOOL_PEN:
  88         case BTN_TOOL_RUBBER:
  89         case BTN_TOOL_BRUSH:
  90         case BTN_TOOL_PENCIL:
  91         case BTN_TOOL_AIRBRUSH:
  92         case BTN_TOOL_FINGER:
  93         case BTN_TOOL_MOUSE:
  94         case BTN_TOOL_LENS:
  95                 if (device->is_touchpad)
  96                 {
  97                         device->abs.reset_x = 1;
  98                         device->abs.reset_y = 1;
  99                 }
 100                 break;
 101         case BTN_TOUCH:
 102                 /* Multitouch touchscreen devices might not send individually
 103                  * button events each time a new finger is down. So we don't
 104                  * send notification for such devices and we solve the button
 105                  * case emulating on compositor side. */
 106                 if (device->is_mt)
 107                         break;
 108
 109                 /* Treat BTN_TOUCH from devices that only have BTN_TOUCH as
 110                  * BTN_LEFT */
 111                 e->code = BTN_LEFT;
 112                 /* Intentional fallthrough! */
 113         case BTN_LEFT:
 114         case BTN_RIGHT:
 115         case BTN_MIDDLE:
 116         case BTN_SIDE:
 117         case BTN_EXTRA:
 118         case BTN_FORWARD:
 119         case BTN_BACK:
 120         case BTN_TASK:
 121                 notify_button(&device->master->base.input_device,
 122                               time, e->code, e->value);
 123                 break;
 124
 125         default:
 126                 notify_key(&device->master->base.input_device,
 127                            time, e->code, e->value);
 128                 break;
 129         }
 130 }
 131
 132 static void
 133 evdev_process_touch(struct evdev_input_device *device,
 134                     struct input_event *e)
 135 {
 136         const int screen_width = device->output->current->width;
 137         const int screen_height = device->output->current->height;
 138
 139         switch (e->code) {
 140         case ABS_MT_SLOT:
 141                 device->mt.slot = e->value;
 142                 break;
 143         case ABS_MT_TRACKING_ID:
 144                 if (e->value >= 0)
 145                         device->type |= EVDEV_ABSOLUTE_MT_DOWN;
 146                 else
 147                         device->type |= EVDEV_ABSOLUTE_MT_UP;
 148                 break;
 149         case ABS_MT_POSITION_X:
 150                 device->mt.x[device->mt.slot] =
 151                         (e->value - device->abs.min_x) * screen_width /
 152                         (device->abs.max_x - device->abs.min_x) +
 153                         device->output->x;
 154                 device->type |= EVDEV_ABSOLUTE_MT_MOTION;
 155                 break;
 156         case ABS_MT_POSITION_Y:
 157                 device->mt.y[device->mt.slot] =
 158                         (e->value - device->abs.min_y) * screen_height /
 159                         (device->abs.max_y - device->abs.min_y) +
 160                         device->output->y;
 161                 device->type |= EVDEV_ABSOLUTE_MT_MOTION;
 162                 break;
 163         }
 164 }
 165
 166 static inline void
 167 evdev_process_absolute_motion(struct evdev_input_device *device,
 168                               struct input_event *e)
 169 {
 170         const int screen_width = device->output->current->width;
 171         const int screen_height = device->output->current->height;
 172
 173         switch (e->code) {
 174         case ABS_X:
 175                 device->abs.x =
 176                         (e->value - device->abs.min_x) * screen_width /
 177                         (device->abs.max_x - device->abs.min_x) +
 178                         device->output->x;
 179                 device->type |= EVDEV_ABSOLUTE_MOTION;
 180                 break;
 181         case ABS_Y:
 182                 device->abs.y =
 183                         (e->value - device->abs.min_y) * screen_height /
 184                         (device->abs.max_y - device->abs.min_y) +
 185                         device->output->y;
 186                 device->type |= EVDEV_ABSOLUTE_MOTION;
 187                 break;
 188         }
 189 }
 190
 191 static inline void
 192 evdev_process_absolute_motion_touchpad(struct evdev_input_device *device,
 193                                        struct input_event *e)
 194 {
 195         /* FIXME: Make this configurable somehow. */
 196         const int touchpad_speed = 700;
 197
 198         switch (e->code) {
 199         case ABS_X:
 200                 e->value -= device->abs.min_x;
 201                 if (device->abs.reset_x)
 202                         device->abs.reset_x = 0;
 203                 else {
 204                         device->rel.dx =
 205                                 (e->value - device->abs.old_x) *
 206                                 touchpad_speed /
 207                                 (device->abs.max_x - device->abs.min_x);
 208                 }
 209                 device->abs.old_x = e->value;
 210                 device->type |= EVDEV_RELATIVE_MOTION;
 211                 break;
 212         case ABS_Y:
 213                 e->value -= device->abs.min_y;
 214                 if (device->abs.reset_y)
 215                         device->abs.reset_y = 0;
 216                 else {
 217                         device->rel.dy =
 218                                 (e->value - device->abs.old_y) *
 219                                 touchpad_speed /
 220                                 /* maybe use x size here to have the same scale? */
 221                                 (device->abs.max_y - device->abs.min_y);
 222                 }
 223                 device->abs.old_y = e->value;
 224                 device->type |= EVDEV_RELATIVE_MOTION;
 225                 break;
 226         }
 227 }
 228
 229 static inline void
 230 evdev_process_relative_motion(struct evdev_input_device *device,
 231                               struct input_event *e)
 232 {
 233         switch (e->code) {
 234         case REL_X:
 235                 device->rel.dx += e->value;
 236                 device->type |= EVDEV_RELATIVE_MOTION;
 237                 break;
 238         case REL_Y:
 239                 device->rel.dy += e->value;
 240                 device->type |= EVDEV_RELATIVE_MOTION;
 241                 break;
 242         }
 243 }
 244
 245 static inline void
 246 evdev_process_absolute(struct evdev_input_device *device,
 247                        struct input_event *e)
 248 {
 249         if (device->is_touchpad) {
 250                 evdev_process_absolute_motion_touchpad(device, e);
 251         } else if (device->is_mt) {
 252                 evdev_process_touch(device, e);
 253         } else {
 254                 evdev_process_absolute_motion(device, e);
 255         }
 256 }
 257
 258 static int
 259 is_motion_event(struct input_event *e)
 260 {
 261         switch (e->type) {
 262         case EV_REL:
 263                 switch (e->code) {
 264                 case REL_X:
 265                 case REL_Y:
 266                         return 1;
 267                 }
 268         case EV_ABS:
 269                 switch (e->code) {
 270                 case ABS_X:
 271                 case ABS_Y:
 272                 case ABS_MT_POSITION_X:
 273                 case ABS_MT_POSITION_Y:
 274                         return 1;
 275                 }
 276         }
 277
 278         return 0;
 279 }
 280
 281 static void
 282 evdev_flush_motion(struct evdev_input_device *device, uint32_t time)
 283 {
 284         struct wl_input_device *master = &device->master->base.input_device;
 285
 286         if (!device->type)
 287                 return;
 288
 289         if (device->type & EVDEV_RELATIVE_MOTION) {
 290                 notify_motion(master, time,
 291                               master->x + device->rel.dx,
 292                               master->y + device->rel.dy);
 293                 device->type &= ~EVDEV_RELATIVE_MOTION;
 294                 device->rel.dx = 0;
 295                 device->rel.dy = 0;
 296         }
 297         if (device->type & EVDEV_ABSOLUTE_MT_DOWN) {
 298                 notify_touch(master, time,
 299                              device->mt.slot,
 300                              device->mt.x[device->mt.slot],
 301                              device->mt.y[device->mt.slot],
 302                              WL_INPUT_DEVICE_TOUCH_DOWN);
 303                 device->type &= ~EVDEV_ABSOLUTE_MT_DOWN;
 304                 device->type &= ~EVDEV_ABSOLUTE_MT_MOTION;
 305         }
 306         if (device->type & EVDEV_ABSOLUTE_MT_MOTION) {
 307                 notify_touch(master, time,
 308                              device->mt.slot,
 309                              device->mt.x[device->mt.slot],
 310                              device->mt.y[device->mt.slot],
 311                              WL_INPUT_DEVICE_TOUCH_MOTION);
 312                 device->type &= ~EVDEV_ABSOLUTE_MT_DOWN;
 313                 device->type &= ~EVDEV_ABSOLUTE_MT_MOTION;
 314         }
 315         if (device->type & EVDEV_ABSOLUTE_MT_UP) {
 316                 notify_touch(master, time, device->mt.slot, 0, 0,
 317                              WL_INPUT_DEVICE_TOUCH_UP);
 318                 device->type &= ~EVDEV_ABSOLUTE_MT_UP;
 319         }
 320         if (device->type & EVDEV_ABSOLUTE_MOTION) {
 321                 notify_motion(master, time, device->abs.x, device->abs.y);
 322                 device->type &= ~EVDEV_ABSOLUTE_MOTION;
 323         }
 324 }
 325
 326 static int
 327 evdev_input_device_data(int fd, uint32_t mask, void *data)
 328 {
 329         struct weston_compositor *ec;
 330         struct evdev_input_device *device = data;
 331         struct input_event ev[8], *e, *end;
 332         int len;
 333         uint32_t time = 0;
 334
 335         ec = device->master->base.compositor;
 336         if (!ec->focus)
 337                 return 1;
 338
 339         len = read(fd, &ev, sizeof ev);
 340         if (len < 0 || len % sizeof e[0] != 0) {
 341                 /* FIXME: call device_removed when errno is ENODEV. */;
 342                 return 1;
 343         }
 344
 345         device->type = 0;
 346
 347         e = ev;
 348         end = (void *) ev + len;
 349         for (e = ev; e < end; e++) {
 350                 time = e->time.tv_sec * 1000 + e->time.tv_usec / 1000;
 351
 352                 /* we try to minimize the amount of notifications to be
 353                  * forwarded to the compositor, so we accumulate motion
 354                  * events and send as a bunch */
 355                 if (!is_motion_event(e))
 356                         evdev_flush_motion(device, time);
 357                 switch (e->type) {
 358                 case EV_REL:
 359                         evdev_process_relative_motion(device, e);
 360                         break;
 361                 case EV_ABS:
 362                         evdev_process_absolute(device, e);
 363                         break;
 364                 case EV_KEY:
 365                         evdev_process_key(device, e, time);
 366                         break;
 367                 }
 368         }
 369
 370         evdev_flush_motion(device, time);
 371
 372         return 1;
 373 }
 374
 375
 376 /* copied from udev/extras/input_id/input_id.c */
 377 /* we must use this kernel-compatible implementation */
 378 #define BITS_PER_LONG (sizeof(unsigned long) * 8)
 379 #define NBITS(x) ((((x)-1)/BITS_PER_LONG)+1)
 380 #define OFF(x)  ((x)%BITS_PER_LONG)
 381 #define BIT(x)  (1UL<<OFF(x))
 382 #define LONG(x) ((x)/BITS_PER_LONG)
 383 #define TEST_BIT(array, bit)    ((array[LONG(bit)] >> OFF(bit)) & 1)
 384 /* end copied */
 385
 386 static int
 387 evdev_configure_device(struct evdev_input_device *device)
 388 {
 389         struct input_absinfo absinfo;
 390         unsigned long ev_bits[NBITS(EV_MAX)];
 391         unsigned long abs_bits[NBITS(ABS_MAX)];
 392         unsigned long key_bits[NBITS(KEY_MAX)];
 393         int has_key, has_abs;
 394
 395         has_key = 0;
 396         has_abs = 0;
 397
 398         ioctl(device->fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits);
 399         if (TEST_BIT(ev_bits, EV_ABS)) {
 400                 has_abs = 1;
 401
 402                 ioctl(device->fd, EVIOCGBIT(EV_ABS, sizeof(abs_bits)),
 403                       abs_bits);
 404                 if (TEST_BIT(abs_bits, ABS_X)) {
 405                         ioctl(device->fd, EVIOCGABS(ABS_X), &absinfo);
 406                         device->abs.min_x = absinfo.minimum;
 407                         device->abs.max_x = absinfo.maximum;
 408                 }
 409                 if (TEST_BIT(abs_bits, ABS_Y)) {
 410                         ioctl(device->fd, EVIOCGABS(ABS_Y), &absinfo);
 411                         device->abs.min_y = absinfo.minimum;
 412                         device->abs.max_y = absinfo.maximum;
 413                 }
 414                 if (TEST_BIT(abs_bits, ABS_MT_SLOT)) {
 415                         device->is_mt = 1;
 416                         device->mt.slot = 0;
 417                 }
 418         }
 419         if (TEST_BIT(ev_bits, EV_KEY)) {
 420                 has_key = 1;
 421                 ioctl(device->fd, EVIOCGBIT(EV_KEY, sizeof(key_bits)),
 422                       key_bits);
 423                 if (TEST_BIT(key_bits, BTN_TOOL_FINGER) &&
 424                              !TEST_BIT(key_bits, BTN_TOOL_PEN))
 425                         device->is_touchpad = 1;
 426         }
 427
 428         /* This rule tries to catch accelerometer devices and opt out. We may
 429          * want to adjust the protocol later adding a proper event for dealing
 430          * with accelerometers and implement here accordingly */
 431         if (has_abs && !has_key)
 432                 return -1;
 433
 434         return 0;
 435 }
 436
 437 static struct evdev_input_device *
 438 evdev_input_device_create(struct evdev_input *master,
 439                           struct wl_display *display, const char *path)
 440 {
 441         struct evdev_input_device *device;
 442         struct wl_event_loop *loop;
 443         struct weston_compositor *ec;
 444         uid_t saved_uid, uid, euid;
 445
 446         device = malloc(sizeof *device);
 447         if (device == NULL)
 448                 return NULL;
 449
 450         ec = master->base.compositor;
 451         device->output =
 452                 container_of(ec->output_list.next, struct weston_output, link);
 453
 454         device->master = master;
 455         device->is_touchpad = 0;
 456         device->is_mt = 0;
 457         device->devnode = strdup(path);
 458         device->mt.slot = -1;
 459         device->rel.dx = 0;
 460         device->rel.dy = 0;
 461
 462         getresuid(&uid, &euid, &saved_uid);
 463         seteuid(saved_uid);
 464         device->fd = open(path, O_RDONLY);
 465         seteuid(euid);
 466         if (device->fd < 0)
 467                 goto err0;
 468
 469         if (evdev_configure_device(device) == -1)
 470                 goto err1;
 471
 472         loop = wl_display_get_event_loop(display);
 473         device->source = wl_event_loop_add_fd(loop, device->fd,
 474                                               WL_EVENT_READABLE,
 475                                               evdev_input_device_data, device);
 476         if (device->source == NULL)
 477                 goto err1;
 478
 479         wl_list_insert(master->devices_list.prev, &device->link);
 480
 481         return device;
 482
 483 err1:
 484         close(device->fd);
 485 err0:
 486         free(device->devnode);
 487         free(device);
 488         return NULL;
 489 }
 490
 491 static const char default_seat[] = "seat0";
 492
 493 static void
 494 device_added(struct udev_device *udev_device, struct evdev_input *master)
 495 {
 496         struct weston_compositor *c;
 497         const char *devnode;
 498         const char *device_seat;
 499
 500         device_seat = udev_device_get_property_value(udev_device, "ID_SEAT");
 501         if (!device_seat)
 502                 device_seat = default_seat;
 503
 504         if (strcmp(device_seat, master->seat_id))
 505                 return;
 506
 507         c = master->base.compositor;
 508         devnode = udev_device_get_devnode(udev_device);
 509         evdev_input_device_create(master, c->wl_display, devnode);
 510 }
 511
 512 static void
 513 device_removed(struct udev_device *udev_device, struct evdev_input *master)
 514 {
 515         const char *devnode = udev_device_get_devnode(udev_device);
 516         struct evdev_input_device *device, *next;
 517
 518         wl_list_for_each_safe(device, next, &master->devices_list, link) {
 519                 if (!strcmp(device->devnode, devnode)) {
 520                         wl_event_source_remove(device->source);
 521                         wl_list_remove(&device->link);
 522                         close(device->fd);
 523                         free(device->devnode);
 524                         free(device);
 525                         break;
 526                 }
 527         }
 528 }
 529
 530 void
 531 evdev_add_devices(struct udev *udev, struct weston_input_device *input_base)
 532 {
 533         struct evdev_input *input = (struct evdev_input *) input_base;
 534         struct udev_enumerate *e;
 535         struct udev_list_entry *entry;
 536         struct udev_device *device;
 537         const char *path;
 538
 539         e = udev_enumerate_new(udev);
 540         udev_enumerate_add_match_subsystem(e, "input");
 541         udev_enumerate_scan_devices(e);
 542         udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(e)) {
 543                 path = udev_list_entry_get_name(entry);
 544                 device = udev_device_new_from_syspath(udev, path);
 545
 546                 if (strncmp("event", udev_device_get_sysname(device), 5) != 0)
 547                         continue;
 548
 549                 device_added(device, input);
 550
 551                 udev_device_unref(device);
 552         }
 553         udev_enumerate_unref(e);
 554
 555         if (wl_list_empty(&input->devices_list)) {
 556                 fprintf(stderr,
 557                         "warning: no input devices on entering Weston. "
 558                         "Possible causes:\n"
 559                         "\t- no permissions to read /dev/input/event*\n"
 560                         "\t- seats misconfigured "
 561                         "(Weston backend option 'seat', "
 562                         "udev device property ID_SEAT)\n");
 563         }
 564 }
 565
 566 static int
 567 evdev_udev_handler(int fd, uint32_t mask, void *data)
 568 {
 569         struct evdev_input *master = data;
 570         struct udev_device *udev_device;
 571         const char *action;
 572
 573         udev_device = udev_monitor_receive_device(master->udev_monitor);
 574         if (!udev_device)
 575                 return 1;
 576
 577         action = udev_device_get_action(udev_device);
 578         if (action) {
 579                 if (strncmp("event", udev_device_get_sysname(udev_device), 5) != 0)
 580                         return 0;
 581
 582                 if (!strcmp(action, "add")) {
 583                         device_added(udev_device, master);
 584                 }
 585                 else if (!strcmp(action, "remove"))
 586                         device_removed(udev_device, master);
 587         }
 588         udev_device_unref(udev_device);
 589
 590         return 0;
 591 }
 592
 593 static int
 594 evdev_config_udev_monitor(struct udev *udev, struct evdev_input *master)
 595 {
 596         struct wl_event_loop *loop;
 597         struct weston_compositor *c = master->base.compositor;
 598
 599         master->udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
 600         if (!master->udev_monitor) {
 601                 fprintf(stderr, "udev: failed to create the udev monitor\n");
 602                 return 0;
 603         }
 604
 605         udev_monitor_filter_add_match_subsystem_devtype(master->udev_monitor,
 606                         "input", NULL);
 607
 608         if (udev_monitor_enable_receiving(master->udev_monitor)) {
 609                 fprintf(stderr, "udev: failed to bind the udev monitor\n");
 610                 return 0;
 611         }
 612
 613         loop = wl_display_get_event_loop(c->wl_display);
 614         wl_event_loop_add_fd(loop, udev_monitor_get_fd(master->udev_monitor),
 615                              WL_EVENT_READABLE, evdev_udev_handler, master);
 616
 617         return 1;
 618 }
 619
 620 void
 621 evdev_input_create(struct weston_compositor *c, struct udev *udev,
 622                    const char *seat)
 623 {
 624         struct evdev_input *input;
 625
 626         input = malloc(sizeof *input);
 627         if (input == NULL)
 628                 return;
 629
 630         memset(input, 0, sizeof *input);
 631         weston_input_device_init(&input->base, c);
 632
 633         wl_list_init(&input->devices_list);
 634         input->seat_id = strdup(seat);
 635         if (!evdev_config_udev_monitor(udev, input)) {
 636                 free(input->seat_id);
 637                 free(input);
 638                 return;
 639         }
 640
 641         evdev_add_devices(udev, &input->base);
 642
 643         c->input_device = &input->base.input_device;
 644 }
 645
 646 void
 647 evdev_remove_devices(struct weston_input_device *input_base)
 648 {
 649         struct evdev_input *input = (struct evdev_input *) input_base;
 650         struct evdev_input_device *device, *next;
 651
 652         wl_list_for_each_safe(device, next, &input->devices_list, link) {
 653                 wl_event_source_remove(device->source);
 654                 wl_list_remove(&device->link);
 655                 close(device->fd);
 656                 free(device->devnode);
 657                 free(device);
 658         }
 659 }
 660
 661 void
 662 evdev_input_destroy(struct weston_input_device *input_base)
 663 {
 664         struct evdev_input *input = (struct evdev_input *) input_base;
 665
 666         evdev_remove_devices(input_base);
 667         wl_list_remove(&input->base.link);
 668         free(input->seat_id);
 669         free(input);
 670 }