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         } touches[16];
 102         int tracking_ids[16];
 103 };
 104
 105 static int magicmouse_firm_touch(struct magicmouse_sc *msc)
 106 {
 107         int touch = -1;
 108         int ii;
 109
 110         /* If there is only one "firm" touch, set touch to its
 111          * tracking ID.
 112          */
 113         for (ii = 0; ii < msc->ntouches; ii++) {
 114                 int idx = msc->tracking_ids[ii];
 115                 if (msc->touches[idx].size < 8) {
 116                         /* Ignore this touch. */
 117                 } else if (touch >= 0) {
 118                         touch = -1;
 119                         break;
 120                 } else {
 121                         touch = idx;
 122                 }
 123         }
 124
 125         return touch;
 126 }
 127
 128 static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
 129 {
 130         int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
 131                 test_bit(BTN_RIGHT, msc->input->key) << 1 |
 132                 test_bit(BTN_MIDDLE, msc->input->key) << 2;
 133
 134         if (emulate_3button) {
 135                 int id;
 136
 137                 /* If some button was pressed before, keep it held
 138                  * down.  Otherwise, if there's exactly one firm
 139                  * touch, use that to override the mouse's guess.
 140                  */
 141                 if (state == 0) {
 142                         /* The button was released. */
 143                 } else if (last_state != 0) {
 144                         state = last_state;
 145                 } else if ((id = magicmouse_firm_touch(msc)) >= 0) {
 146                         int x = msc->touches[id].x;
 147                         if (x < middle_button_start)
 148                                 state = 1;
 149                         else if (x > middle_button_stop)
 150                                 state = 2;
 151                         else
 152                                 state = 4;
 153                 } /* else: we keep the mouse's guess */
 154
 155                 input_report_key(msc->input, BTN_MIDDLE, state & 4);
 156         }
 157
 158         input_report_key(msc->input, BTN_LEFT, state & 1);
 159         input_report_key(msc->input, BTN_RIGHT, state & 2);
 160
 161         if (state != last_state)
 162                 msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 163 }
 164
 165 static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
 166 {
 167         struct input_dev *input = msc->input;
 168         __s32 x_y = tdata[0] << 8 | tdata[1] << 16 | tdata[2] << 24;
 169         int misc = tdata[5] | tdata[6] << 8;
 170         int id = (misc >> 6) & 15;
 171         int x = x_y << 12 >> 20;
 172         int y = -(x_y >> 20);
 173
 174         /* Store tracking ID and other fields. */
 175         msc->tracking_ids[raw_id] = id;
 176         msc->touches[id].x = x;
 177         msc->touches[id].y = y;
 178         msc->touches[id].size = misc & 63;
 179
 180         /* If requested, emulate a scroll wheel by detecting small
 181          * vertical touch motions.
 182          */
 183         if (emulate_scroll_wheel) {
 184                 unsigned long now = jiffies;
 185                 int step_x = msc->touches[id].scroll_x - x;
 186                 int step_y = msc->touches[id].scroll_y - y;
 187
 188                 /* Calculate and apply the scroll motion. */
 189                 switch (tdata[7] & TOUCH_STATE_MASK) {
 190                 case TOUCH_STATE_START:
 191                         msc->touches[id].scroll_x = x;
 192                         msc->touches[id].scroll_y = y;
 193
 194                         /* Reset acceleration after half a second. */
 195                         if (scroll_acceleration && time_before(now,
 196                                                 msc->scroll_jiffies + HZ / 2))
 197                                 msc->scroll_accel = max_t(int,
 198                                                 msc->scroll_accel - 1, 1);
 199                         else
 200                                 msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 201
 202                         break;
 203                 case TOUCH_STATE_DRAG:
 204                         step_x /= (64 - (int)scroll_speed) * msc->scroll_accel;
 205                         if (step_x != 0) {
 206                                 msc->touches[id].scroll_x -= step_x *
 207                                         (64 - scroll_speed) * msc->scroll_accel;
 208                                 msc->scroll_jiffies = now;
 209                                 input_report_rel(input, REL_HWHEEL, -step_x);
 210                         }
 211
 212                         step_y /= (64 - (int)scroll_speed) * msc->scroll_accel;
 213                         if (step_y != 0) {
 214                                 msc->touches[id].scroll_y -= step_y *
 215                                         (64 - scroll_speed) * msc->scroll_accel;
 216                                 msc->scroll_jiffies = now;
 217                                 input_report_rel(input, REL_WHEEL, step_y);
 218                         }
 219                         break;
 220                 }
 221         }
 222
 223         /* Generate the input events for this touch. */
 224         if (report_touches) {
 225                 int orientation = (misc >> 10) - 32;
 226
 227                 input_report_abs(input, ABS_MT_TRACKING_ID, id);
 228                 input_report_abs(input, ABS_MT_TOUCH_MAJOR, tdata[3]);
 229                 input_report_abs(input, ABS_MT_TOUCH_MINOR, tdata[4]);
 230                 input_report_abs(input, ABS_MT_ORIENTATION, orientation);
 231                 input_report_abs(input, ABS_MT_POSITION_X, x);
 232                 input_report_abs(input, ABS_MT_POSITION_Y, y);
 233
 234                 if (report_undeciphered)
 235                         input_event(input, EV_MSC, MSC_RAW, tdata[7]);
 236
 237                 input_mt_sync(input);
 238         }
 239 }
 240
 241 static int magicmouse_raw_event(struct hid_device *hdev,
 242                 struct hid_report *report, u8 *data, int size)
 243 {
 244         struct magicmouse_sc *msc = hid_get_drvdata(hdev);
 245         struct input_dev *input = msc->input;
 246         int x, y, ts, ii, clicks;
 247
 248         switch (data[0]) {
 249         case 0x10:
 250                 if (size != 6)
 251                         return 0;
 252                 x = (__s16)(data[2] | data[3] << 8);
 253                 y = (__s16)(data[4] | data[5] << 8);
 254                 clicks = data[1];
 255                 break;
 256         case TOUCH_REPORT_ID:
 257                 /* Expect six bytes of prefix, and N*8 bytes of touch data. */
 258                 if (size < 6 || ((size - 6) % 8) != 0)
 259                         return 0;
 260                 ts = data[3] >> 6 | data[4] << 2 | data[5] << 10;
 261                 msc->delta_time = (ts - msc->last_timestamp) & 0x3ffff;
 262                 msc->last_timestamp = ts;
 263                 msc->ntouches = (size - 6) / 8;
 264                 for (ii = 0; ii < msc->ntouches; ii++)
 265                         magicmouse_emit_touch(msc, ii, data + ii * 8 + 6);
 266                 /* When emulating three-button mode, it is important
 267                  * to have the current touch information before
 268                  * generating a click event.
 269                  */
 270                 x = (signed char)data[1];
 271                 y = (signed char)data[2];
 272                 clicks = data[3];
 273                 break;
 274         case 0x20: /* Theoretically battery status (0-100), but I have
 275                     * never seen it -- maybe it is only upon request.
 276                     */
 277         case 0x60: /* Unknown, maybe laser on/off. */
 278         case 0x61: /* Laser reflection status change.
 279                     * data[1]: 0 = spotted, 1 = lost
 280                     */
 281         default:
 282                 return 0;
 283         }
 284
 285         magicmouse_emit_buttons(msc, clicks & 3);
 286         input_report_rel(input, REL_X, x);
 287         input_report_rel(input, REL_Y, y);
 288         input_sync(input);
 289         return 1;
 290 }
 291
 292 static int magicmouse_input_open(struct input_dev *dev)
 293 {
 294         struct hid_device *hid = input_get_drvdata(dev);
 295
 296         return hid->ll_driver->open(hid);
 297 }
 298
 299 static void magicmouse_input_close(struct input_dev *dev)
 300 {
 301         struct hid_device *hid = input_get_drvdata(dev);
 302
 303         hid->ll_driver->close(hid);
 304 }
 305
 306 static void magicmouse_setup_input(struct input_dev *input, struct hid_device *hdev)
 307 {
 308         input_set_drvdata(input, hdev);
 309         input->event = hdev->ll_driver->hidinput_input_event;
 310         input->open = magicmouse_input_open;
 311         input->close = magicmouse_input_close;
 312
 313         input->name = hdev->name;
 314         input->phys = hdev->phys;
 315         input->uniq = hdev->uniq;
 316         input->id.bustype = hdev->bus;
 317         input->id.vendor = hdev->vendor;
 318         input->id.product = hdev->product;
 319         input->id.version = hdev->version;
 320         input->dev.parent = hdev->dev.parent;
 321
 322         __set_bit(EV_KEY, input->evbit);
 323         __set_bit(BTN_LEFT, input->keybit);
 324         __set_bit(BTN_RIGHT, input->keybit);
 325         if (emulate_3button)
 326                 __set_bit(BTN_MIDDLE, input->keybit);
 327         __set_bit(BTN_TOOL_FINGER, input->keybit);
 328
 329         __set_bit(EV_REL, input->evbit);
 330         __set_bit(REL_X, input->relbit);
 331         __set_bit(REL_Y, input->relbit);
 332         if (emulate_scroll_wheel) {
 333                 __set_bit(REL_WHEEL, input->relbit);
 334                 __set_bit(REL_HWHEEL, input->relbit);
 335         }
 336
 337         if (report_touches) {
 338                 __set_bit(EV_ABS, input->evbit);
 339
 340                 input_set_abs_params(input, ABS_MT_TRACKING_ID, 0, 15, 0, 0);
 341                 input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 4, 0);
 342                 input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 255, 4, 0);
 343                 input_set_abs_params(input, ABS_MT_ORIENTATION, -32, 31, 1, 0);
 344                 input_set_abs_params(input, ABS_MT_POSITION_X, -1100, 1358,
 345                                 4, 0);
 346                 /* Note: Touch Y position from the device is inverted relative
 347                  * to how pointer motion is reported (and relative to how USB
 348                  * HID recommends the coordinates work).  This driver keeps
 349                  * the origin at the same position, and just uses the additive
 350                  * inverse of the reported Y.
 351                  */
 352                 input_set_abs_params(input, ABS_MT_POSITION_Y, -1589, 2047,
 353                                 4, 0);
 354         }
 355
 356         if (report_undeciphered) {
 357                 __set_bit(EV_MSC, input->evbit);
 358                 __set_bit(MSC_RAW, input->mscbit);
 359         }
 360 }
 361
 362 static int magicmouse_probe(struct hid_device *hdev,
 363         const struct hid_device_id *id)
 364 {
 365         __u8 feature_1[] = { 0xd7, 0x01 };
 366         __u8 feature_2[] = { 0xf8, 0x01, 0x32 };
 367         struct input_dev *input;
 368         struct magicmouse_sc *msc;
 369         struct hid_report *report;
 370         int ret;
 371
 372         msc = kzalloc(sizeof(*msc), GFP_KERNEL);
 373         if (msc == NULL) {
 374                 dev_err(&hdev->dev, "can't alloc magicmouse descriptor\n");
 375                 return -ENOMEM;
 376         }
 377
 378         msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
 379
 380         msc->quirks = id->driver_data;
 381         hid_set_drvdata(hdev, msc);
 382
 383         ret = hid_parse(hdev);
 384         if (ret) {
 385                 dev_err(&hdev->dev, "magicmouse hid parse failed\n");
 386                 goto err_free;
 387         }
 388
 389         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 390         if (ret) {
 391                 dev_err(&hdev->dev, "magicmouse hw start failed\n");
 392                 goto err_free;
 393         }
 394
 395         /* we are handling the input ourselves */
 396         hidinput_disconnect(hdev);
 397
 398         report = hid_register_report(hdev, HID_INPUT_REPORT, TOUCH_REPORT_ID);
 399         if (!report) {
 400                 dev_err(&hdev->dev, "unable to register touch report\n");
 401                 ret = -ENOMEM;
 402                 goto err_stop_hw;
 403         }
 404         report->size = 6;
 405
 406         ret = hdev->hid_output_raw_report(hdev, feature_1, sizeof(feature_1),
 407                         HID_FEATURE_REPORT);
 408         if (ret != sizeof(feature_1)) {
 409                 dev_err(&hdev->dev, "unable to request touch data (1:%d)\n",
 410                                 ret);
 411                 goto err_stop_hw;
 412         }
 413         ret = hdev->hid_output_raw_report(hdev, feature_2,
 414                         sizeof(feature_2), HID_FEATURE_REPORT);
 415         if (ret != sizeof(feature_2)) {
 416                 dev_err(&hdev->dev, "unable to request touch data (2:%d)\n",
 417                                 ret);
 418                 goto err_stop_hw;
 419         }
 420
 421         input = input_allocate_device();
 422         if (!input) {
 423                 dev_err(&hdev->dev, "can't alloc input device\n");
 424                 ret = -ENOMEM;
 425                 goto err_stop_hw;
 426         }
 427         magicmouse_setup_input(input, hdev);
 428
 429         ret = input_register_device(input);
 430         if (ret) {
 431                 dev_err(&hdev->dev, "input device registration failed\n");
 432                 goto err_input;
 433         }
 434         msc->input = input;
 435
 436         return 0;
 437 err_input:
 438         input_free_device(input);
 439 err_stop_hw:
 440         hid_hw_stop(hdev);
 441 err_free:
 442         kfree(msc);
 443         return ret;
 444 }
 445
 446 static void magicmouse_remove(struct hid_device *hdev)
 447 {
 448         struct magicmouse_sc *msc = hid_get_drvdata(hdev);
 449
 450         hid_hw_stop(hdev);
 451         input_unregister_device(msc->input);
 452         kfree(msc);
 453 }
 454
 455 static const struct hid_device_id magic_mice[] = {
 456         { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICMOUSE),
 457                 .driver_data = 0 },
 458         { }
 459 };
 460 MODULE_DEVICE_TABLE(hid, magic_mice);
 461
 462 static struct hid_driver magicmouse_driver = {
 463         .name = "magicmouse",
 464         .id_table = magic_mice,
 465         .probe = magicmouse_probe,
 466         .remove = magicmouse_remove,
 467         .raw_event = magicmouse_raw_event,
 468 };
 469
 470 static int __init magicmouse_init(void)
 471 {
 472         int ret;
 473
 474         ret = hid_register_driver(&magicmouse_driver);
 475         if (ret)
 476                 printk(KERN_ERR "can't register magicmouse driver\n");
 477
 478         return ret;
 479 }
 480
 481 static void __exit magicmouse_exit(void)
 482 {
 483         hid_unregister_driver(&magicmouse_driver);
 484 }
 485
 486 module_init(magicmouse_init);
 487 module_exit(magicmouse_exit);
 488 MODULE_LICENSE("GPL");