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