drivers/hid/hid-magicmouse.c

   1 /*
   2  *   Apple "Magic" Wireless Mouse driver
   3  *
   4  *   Copyright (c) 2010 Michael Poole <mdpoole@troilus.org>
   5  */
   6
   7 /*
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the Free
  10  * Software Foundation; either version 2 of the License, or (at your option)
  11  * any later version.
  12  */
  13
  14 #include <linux/device.h>
  15 #include <linux/hid.h>
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/usb.h>
  19
  20 #include "hid-ids.h"
  21
  22 static bool emulate_3button = true;
  23 module_param(emulate_3button, bool, 0644);
  24 MODULE_PARM_DESC(emulate_3button, "Emulate a middle button");
  25
  26 static int middle_button_start = -350;
  27 static int middle_button_stop = +350;
  28
  29 static bool emulate_scroll_wheel = true;
  30 module_param(emulate_scroll_wheel, bool, 0644);
  31 MODULE_PARM_DESC(emulate_scroll_wheel, "Emulate a scroll wheel");
  32
  33 static unsigned int scroll_speed = 32;
  34 static int param_set_scroll_speed(const char *val, struct kernel_param *kp) {
  35         unsigned long speed;
  36         if (!val || strict_strtoul(val, 0, &speed) || speed > 63)
  37                 return -EINVAL;
  38         scroll_speed = speed;
  39         return 0;
  40 }
  41 module_param_call(scroll_speed, param_set_scroll_speed, param_get_uint, &scroll_speed, 0644);
  42 MODULE_PARM_DESC(scroll_speed, "Scroll speed, value from 0 (slow) to 63 (fast)");
  43
  44 static bool scroll_acceleration = false;
  45 module_param(scroll_acceleration, bool, 0644);
  46 MODULE_PARM_DESC(scroll_acceleration, "Accelerate sequential scroll events");
  47
  48 static bool report_touches = true;
  49 module_param(report_touches, bool, 0644);
  50 MODULE_PARM_DESC(report_touches, "Emit touch records (otherwise, only use them for emulation)");
  51
  52 static bool report_undeciphered;
  53 module_param(report_undeciphered, bool, 0644);
  54 MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");
  55
  56 #define TOUCH_REPORT_ID   0x29
  57 /* These definitions are not precise, but they're close enough.  (Bits
  58  * 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
  59  * to be some kind of bit mask -- 0x20 may be a near-field reading,
  60  * and 0x40 is actual contact, and 0x10 may be a start/stop or change
  61  * indication.)
  62  */
  63 #define TOUCH_STATE_MASK  0xf0
  64 #define TOUCH_STATE_NONE  0x00
  65 #define TOUCH_STATE_START 0x30
  66 #define TOUCH_STATE_DRAG  0x40
  67
  68 #define SCROLL_ACCEL_DEFAULT 7
  69
  70 /**
  71  * struct magicmouse_sc - Tracks Magic Mouse-specific data.
  72  * @input: Input device through which we report events.
  73  * @quirks: Currently unused.
  74  * @last_timestamp: Timestamp from most recent (18-bit) touch report
  75  *     (units of milliseconds over short windows, but seems to
  76  *     increase faster when there are no touches).
  77  * @delta_time: 18-bit difference between the two most recent touch
  78  *     reports from the mouse.
  79  * @ntouches: Number of touches in most recent touch report.
  80  * @scroll_accel: Number of consecutive scroll motions.
  81  * @scroll_jiffies: Time of last scroll motion.
  82  * @touches: Most recent data for a touch, indexed by tracking ID.
  83  * @tracking_ids: Mapping of current touch input data to @touches.
  84  */
  85 struct magicmouse_sc {
  86         struct input_dev *input;
  87         unsigned long quirks;
  88
  89         int last_timestamp;
  90         int delta_time;
  91         int ntouches;
  92         int scroll_accel;
  93         unsigned long scroll_jiffies;
  94
  95         struct {
  96                 short x;
  97                 short y;
  98                 short scroll_x;
  99                 short scroll_y;
 100                 u8 size;
 101                 u8 down;
 102         } touches[16];
 103         int tracking_ids[16];
 104 };
 105
 106 static int magicmouse_firm_touch(struct magicmouse_sc *msc)
 107 {
 108         int touch = -1;
 109         int ii;
 110
 111         /* If there is only one "firm" touch, set touch to its
 112          * tracking ID.
 113          */
 114         for (ii = 0; ii < msc->ntouches; ii++) {
 115                 int idx = msc->tracking_ids[ii];
 116                 if (msc->touches[idx].size < 8) {
 117                         /* Ignore this touch. */
 118                 } else if (touch >= 0) {
 119                         touch = -1;
 120                         break;
 121                 } else {
 122                         touch = idx;
 123                 }
 124         }
 125
 126         return touch;
 127 }
 128
 129 static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
 130 {
 131         int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
 132                 test_bit(BTN_RIGHT, msc->input->key) << 1 |
 133                 test_bit(BTN_MIDDLE, msc->input->key) << 2;
 134
 135         if (emulate_3button) {
 136                 int id;
 137
 138                 /* If some button was pressed before, keep it held
 139                  * down.  Otherwise, if there's exactly one firm
 140                  * touch, use that to override the mouse's guess.
 141                  */
 142                 if (state == 0) {
 143                         /* The button was released. */
 144                 } else if (last_state != 0) {
 145                         state = last_state;
 146                 } else if ((id = magicmouse_firm_touch(msc)) >= 0) {
 147                         int x = msc->touches[id].x;
 148                         if (x < middle_button_start)
 149                                 state = 1;
 150                         else if (x > middle_button_stop)
 151                                 state = 2;
 152                         else
 153                                 state = 4;
 154                 } /* else: we keep the mouse's guess */
 155
 156                 input_report_key(msc->input, BTN_MIDDLE, state & 4);
 157         }
 158
 159         input_report_key(msc->input, BTN_LEFT, state & 1);
 160         input_report_key(msc->input, BTN_RIGHT, state & 2);
 161
 162         if (state != last_state)
 163                 msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 164 }
 165
 166 static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
 167 {
 168         struct input_dev *input = msc->input;
 169         __s32 x_y = tdata[0] << 8 | tdata[1] << 16 | tdata[2] << 24;
 170         int misc = tdata[5] | tdata[6] << 8;
 171         int id = (misc >> 6) & 15;
 172         int x = x_y << 12 >> 20;
 173         int y = -(x_y >> 20);
 174         int down = (tdata[7] & TOUCH_STATE_MASK) != TOUCH_STATE_NONE;
 175
 176         /* Store tracking ID and other fields. */
 177         msc->tracking_ids[raw_id] = id;
 178         msc->touches[id].x = x;
 179         msc->touches[id].y = y;
 180         msc->touches[id].size = misc & 63;
 181
 182         /* If requested, emulate a scroll wheel by detecting small
 183          * vertical touch motions.
 184          */
 185         if (emulate_scroll_wheel) {
 186                 unsigned long now = jiffies;
 187                 int step_x = msc->touches[id].scroll_x - x;
 188                 int step_y = msc->touches[id].scroll_y - y;
 189
 190                 /* Calculate and apply the scroll motion. */
 191                 switch (tdata[7] & TOUCH_STATE_MASK) {
 192                 case TOUCH_STATE_START:
 193                         msc->touches[id].scroll_x = x;
 194                         msc->touches[id].scroll_y = y;
 195
 196                         /* Reset acceleration after half a second. */
 197                         if (scroll_acceleration && time_before(now,
 198                                                 msc->scroll_jiffies + HZ / 2))
 199                                 msc->scroll_accel = max_t(int,
 200                                                 msc->scroll_accel - 1, 1);
 201                         else
 202                                 msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 203
 204                         break;
 205                 case TOUCH_STATE_DRAG:
 206                         step_x /= (64 - (int)scroll_speed) * msc->scroll_accel;
 207                         if (step_x != 0) {
 208                                 msc->touches[id].scroll_x -= step_x *
 209                                         (64 - scroll_speed) * msc->scroll_accel;
 210                                 msc->scroll_jiffies = now;
 211                                 input_report_rel(input, REL_HWHEEL, -step_x);
 212                         }
 213
 214                         step_y /= (64 - (int)scroll_speed) * msc->scroll_accel;
 215                         if (step_y != 0) {
 216                                 msc->touches[id].scroll_y -= step_y *
 217                                         (64 - scroll_speed) * msc->scroll_accel;
 218                                 msc->scroll_jiffies = now;
 219                                 input_report_rel(input, REL_WHEEL, step_y);
 220                         }
 221                         break;
 222                 }
 223         }
 224
 225         /* Generate the input events for this touch. */
 226         if (report_touches && down) {
 227                 int orientation = (misc >> 10) - 32;
 228
 229                 msc->touches[id].down = 1;
 230
 231                 input_report_abs(input, ABS_MT_TRACKING_ID, id);
 232                 input_report_abs(input, ABS_MT_TOUCH_MAJOR, tdata[3]);
 233                 input_report_abs(input, ABS_MT_TOUCH_MINOR, tdata[4]);
 234                 input_report_abs(input, ABS_MT_ORIENTATION, orientation);
 235                 input_report_abs(input, ABS_MT_POSITION_X, x);
 236                 input_report_abs(input, ABS_MT_POSITION_Y, y);
 237
 238                 if (report_undeciphered)
 239                         input_event(input, EV_MSC, MSC_RAW, tdata[7]);
 240
 241                 input_mt_sync(input);
 242         }
 243 }
 244
 245 static int magicmouse_raw_event(struct hid_device *hdev,
 246                 struct hid_report *report, u8 *data, int size)
 247 {
 248         struct magicmouse_sc *msc = hid_get_drvdata(hdev);
 249         struct input_dev *input = msc->input;
 250         int x, y, ts, ii, clicks, last_up;
 251
 252         switch (data[0]) {
 253         case 0x10:
 254                 if (size != 6)
 255                         return 0;
 256                 x = (__s16)(data[2] | data[3] << 8);
 257                 y = (__s16)(data[4] | data[5] << 8);
 258                 clicks = data[1];
 259                 break;
 260         case TOUCH_REPORT_ID:
 261                 /* Expect six bytes of prefix, and N*8 bytes of touch data. */
 262                 if (size < 6 || ((size - 6) % 8) != 0)
 263                         return 0;
 264                 ts = data[3] >> 6 | data[4] << 2 | data[5] << 10;
 265                 msc->delta_time = (ts - msc->last_timestamp) & 0x3ffff;
 266                 msc->last_timestamp = ts;
 267                 msc->ntouches = (size - 6) / 8;
 268                 for (ii = 0; ii < msc->ntouches; ii++)
 269                         magicmouse_emit_touch(msc, ii, data + ii * 8 + 6);
 270
 271                 if (report_touches) {
 272                         last_up = 1;
 273                         for (ii = 0; ii < ARRAY_SIZE(msc->touches); ii++) {
 274                                 if (msc->touches[ii].down) {
 275                                         last_up = 0;
 276                                         msc->touches[ii].down = 0;
 277                                 }
 278                         }
 279                         if (last_up) {
 280                                 input_mt_sync(input);
 281                         }
 282                 }
 283
 284                 /* When emulating three-button mode, it is important
 285                  * to have the current touch information before
 286                  * generating a click event.
 287                  */
 288                 x = (int)(((data[3] & 0x0c) << 28) | (data[1] << 22)) >> 22;
 289                 y = (int)(((data[3] & 0x30) << 26) | (data[2] << 22)) >> 22;
 290                 clicks = data[3];
 291                 break;
 292         case 0x20: /* Theoretically battery status (0-100), but I have
 293                     * never seen it -- maybe it is only upon request.
 294                     */
 295         case 0x60: /* Unknown, maybe laser on/off. */
 296         case 0x61: /* Laser reflection status change.
 297                     * data[1]: 0 = spotted, 1 = lost
 298                     */
 299         default:
 300                 return 0;
 301         }
 302
 303         magicmouse_emit_buttons(msc, clicks & 3);
 304         input_report_rel(input, REL_X, x);
 305         input_report_rel(input, REL_Y, y);
 306         input_sync(input);
 307         return 1;
 308 }
 309
 310 static int magicmouse_input_open(struct input_dev *dev)
 311 {
 312         struct hid_device *hid = input_get_drvdata(dev);
 313
 314         return hid->ll_driver->open(hid);
 315 }
 316
 317 static void magicmouse_input_close(struct input_dev *dev)
 318 {
 319         struct hid_device *hid = input_get_drvdata(dev);
 320
 321         hid->ll_driver->close(hid);
 322 }
 323
 324 static void magicmouse_setup_input(struct input_dev *input, struct hid_device *hdev)
 325 {
 326         input_set_drvdata(input, hdev);
 327         input->event = hdev->ll_driver->hidinput_input_event;
 328         input->open = magicmouse_input_open;
 329         input->close = magicmouse_input_close;
 330
 331         input->name = hdev->name;
 332         input->phys = hdev->phys;
 333         input->uniq = hdev->uniq;
 334         input->id.bustype = hdev->bus;
 335         input->id.vendor = hdev->vendor;
 336         input->id.product = hdev->product;
 337         input->id.version = hdev->version;
 338         input->dev.parent = hdev->dev.parent;
 339
 340         __set_bit(EV_KEY, input->evbit);
 341         __set_bit(BTN_LEFT, input->keybit);
 342         __set_bit(BTN_RIGHT, input->keybit);
 343         if (emulate_3button)
 344                 __set_bit(BTN_MIDDLE, input->keybit);
 345         __set_bit(BTN_TOOL_FINGER, input->keybit);
 346
 347         __set_bit(EV_REL, input->evbit);
 348         __set_bit(REL_X, input->relbit);
 349         __set_bit(REL_Y, input->relbit);
 350         if (emulate_scroll_wheel) {
 351                 __set_bit(REL_WHEEL, input->relbit);
 352                 __set_bit(REL_HWHEEL, input->relbit);
 353         }
 354
 355         if (report_touches) {
 356                 __set_bit(EV_ABS, input->evbit);
 357
 358                 input_set_abs_params(input, ABS_MT_TRACKING_ID, 0, 15, 0, 0);
 359                 input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 4, 0);
 360                 input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 255, 4, 0);
 361                 input_set_abs_params(input, ABS_MT_ORIENTATION, -32, 31, 1, 0);
 362                 input_set_abs_params(input, ABS_MT_POSITION_X, -1100, 1358,
 363                                 4, 0);
 364                 /* Note: Touch Y position from the device is inverted relative
 365                  * to how pointer motion is reported (and relative to how USB
 366                  * HID recommends the coordinates work).  This driver keeps
 367                  * the origin at the same position, and just uses the additive
 368                  * inverse of the reported Y.
 369                  */
 370                 input_set_abs_params(input, ABS_MT_POSITION_Y, -1589, 2047,
 371                                 4, 0);
 372         }
 373
 374         if (report_undeciphered) {
 375                 __set_bit(EV_MSC, input->evbit);
 376                 __set_bit(MSC_RAW, input->mscbit);
 377         }
 378 }
 379
 380 static int magicmouse_probe(struct hid_device *hdev,
 381         const struct hid_device_id *id)
 382 {
 383         __u8 feature_1[] = { 0xd7, 0x01 };
 384         __u8 feature_2[] = { 0xf8, 0x01, 0x32 };
 385         struct input_dev *input;
 386         struct magicmouse_sc *msc;
 387         struct hid_report *report;
 388         int ret;
 389
 390         msc = kzalloc(sizeof(*msc), GFP_KERNEL);
 391         if (msc == NULL) {
 392                 dev_err(&hdev->dev, "can't alloc magicmouse descriptor\n");
 393                 return -ENOMEM;
 394         }
 395
 396         msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 397
 398         msc->quirks = id->driver_data;
 399         hid_set_drvdata(hdev, msc);
 400
 401         ret = hid_parse(hdev);
 402         if (ret) {
 403                 dev_err(&hdev->dev, "magicmouse hid parse failed\n");
 404                 goto err_free;
 405         }
 406
 407         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 408         if (ret) {
 409                 dev_err(&hdev->dev, "magicmouse hw start failed\n");
 410                 goto err_free;
 411         }
 412
 413         /* we are handling the input ourselves */
 414         hidinput_disconnect(hdev);
 415
 416         report = hid_register_report(hdev, HID_INPUT_REPORT, TOUCH_REPORT_ID);
 417         if (!report) {
 418                 dev_err(&hdev->dev, "unable to register touch report\n");
 419                 ret = -ENOMEM;
 420                 goto err_stop_hw;
 421         }
 422         report->size = 6;
 423
 424         ret = hdev->hid_output_raw_report(hdev, feature_1, sizeof(feature_1),
 425                         HID_FEATURE_REPORT);
 426         if (ret != sizeof(feature_1)) {
 427                 dev_err(&hdev->dev, "unable to request touch data (1:%d)\n",
 428                                 ret);
 429                 goto err_stop_hw;
 430         }
 431         ret = hdev->hid_output_raw_report(hdev, feature_2,
 432                         sizeof(feature_2), HID_FEATURE_REPORT);
 433         if (ret != sizeof(feature_2)) {
 434                 dev_err(&hdev->dev, "unable to request touch data (2:%d)\n",
 435                                 ret);
 436                 goto err_stop_hw;
 437         }
 438
 439         input = input_allocate_device();
 440         if (!input) {
 441                 dev_err(&hdev->dev, "can't alloc input device\n");
 442                 ret = -ENOMEM;
 443                 goto err_stop_hw;
 444         }
 445         magicmouse_setup_input(input, hdev);
 446
 447         ret = input_register_device(input);
 448         if (ret) {
 449                 dev_err(&hdev->dev, "input device registration failed\n");
 450                 goto err_input;
 451         }
 452         msc->input = input;
 453
 454         return 0;
 455 err_input:
 456         input_free_device(input);
 457 err_stop_hw:
 458         hid_hw_stop(hdev);
 459 err_free:
 460         kfree(msc);
 461         return ret;
 462 }
 463
 464 static void magicmouse_remove(struct hid_device *hdev)
 465 {
 466         struct magicmouse_sc *msc = hid_get_drvdata(hdev);
 467
 468         hid_hw_stop(hdev);
 469         input_unregister_device(msc->input);
 470         kfree(msc);
 471 }
 472
 473 static const struct hid_device_id magic_mice[] = {
 474         { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICMOUSE),
 475                 .driver_data = 0 },
 476         { }
 477 };
 478 MODULE_DEVICE_TABLE(hid, magic_mice);
 479
 480 static struct hid_driver magicmouse_driver = {
 481         .name = "magicmouse",
 482         .id_table = magic_mice,
 483         .probe = magicmouse_probe,
 484         .remove = magicmouse_remove,
 485         .raw_event = magicmouse_raw_event,
 486 };
 487
 488 static int __init magicmouse_init(void)
 489 {
 490         int ret;
 491
 492         ret = hid_register_driver(&magicmouse_driver);
 493         if (ret)
 494                 printk(KERN_ERR "can't register magicmouse driver\n");
 495
 496         return ret;
 497 }
 498
 499 static void __exit magicmouse_exit(void)
 500 {
 501         hid_unregister_driver(&magicmouse_driver);
 502 }
 503
 504 module_init(magicmouse_init);
 505 module_exit(magicmouse_exit);
 506 MODULE_LICENSE("GPL");