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