drivers/usb/input/hid-pidff.c

   1 /*
   2  *  Force feedback driver for USB HID PID compliant devices
   3  *
   4  *  Copyright (c) 2005, 2006 Anssi Hannula <anssi.hannula@gmail.com>
   5  */
   6
   7 /*
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22
  23 /* #define DEBUG */
  24
  25 #define debug(format, arg...) pr_debug("hid-pidff: " format "\n" , ## arg)
  26
  27 #include <linux/input.h>
  28 #include <linux/usb.h>
  29
  30 #include <linux/hid.h>
  31
  32 #include "usbhid.h"
  33
  34 #define PID_EFFECTS_MAX         64
  35
  36 /* Report usage table used to put reports into an array */
  37
  38 #define PID_SET_EFFECT          0
  39 #define PID_EFFECT_OPERATION    1
  40 #define PID_DEVICE_GAIN         2
  41 #define PID_POOL                3
  42 #define PID_BLOCK_LOAD          4
  43 #define PID_BLOCK_FREE          5
  44 #define PID_DEVICE_CONTROL      6
  45 #define PID_CREATE_NEW_EFFECT   7
  46
  47 #define PID_REQUIRED_REPORTS    7
  48
  49 #define PID_SET_ENVELOPE        8
  50 #define PID_SET_CONDITION       9
  51 #define PID_SET_PERIODIC        10
  52 #define PID_SET_CONSTANT        11
  53 #define PID_SET_RAMP            12
  54 static const u8 pidff_reports[] = {
  55         0x21, 0x77, 0x7d, 0x7f, 0x89, 0x90, 0x96, 0xab,
  56         0x5a, 0x5f, 0x6e, 0x73, 0x74
  57 };
  58
  59 /* device_control is really 0x95, but 0x96 specified as it is the usage of
  60 the only field in that report */
  61
  62 /* Value usage tables used to put fields and values into arrays */
  63
  64 #define PID_EFFECT_BLOCK_INDEX  0
  65
  66 #define PID_DURATION            1
  67 #define PID_GAIN                2
  68 #define PID_TRIGGER_BUTTON      3
  69 #define PID_TRIGGER_REPEAT_INT  4
  70 #define PID_DIRECTION_ENABLE    5
  71 #define PID_START_DELAY         6
  72 static const u8 pidff_set_effect[] = {
  73         0x22, 0x50, 0x52, 0x53, 0x54, 0x56, 0xa7
  74 };
  75
  76 #define PID_ATTACK_LEVEL        1
  77 #define PID_ATTACK_TIME         2
  78 #define PID_FADE_LEVEL          3
  79 #define PID_FADE_TIME           4
  80 static const u8 pidff_set_envelope[] = { 0x22, 0x5b, 0x5c, 0x5d, 0x5e };
  81
  82 #define PID_PARAM_BLOCK_OFFSET  1
  83 #define PID_CP_OFFSET           2
  84 #define PID_POS_COEFFICIENT     3
  85 #define PID_NEG_COEFFICIENT     4
  86 #define PID_POS_SATURATION      5
  87 #define PID_NEG_SATURATION      6
  88 #define PID_DEAD_BAND           7
  89 static const u8 pidff_set_condition[] = {
  90         0x22, 0x23, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65
  91 };
  92
  93 #define PID_MAGNITUDE           1
  94 #define PID_OFFSET              2
  95 #define PID_PHASE               3
  96 #define PID_PERIOD              4
  97 static const u8 pidff_set_periodic[] = { 0x22, 0x70, 0x6f, 0x71, 0x72 };
  98 static const u8 pidff_set_constant[] = { 0x22, 0x70 };
  99
 100 #define PID_RAMP_START          1
 101 #define PID_RAMP_END            2
 102 static const u8 pidff_set_ramp[] = { 0x22, 0x75, 0x76 };
 103
 104 #define PID_RAM_POOL_AVAILABLE  1
 105 static const u8 pidff_block_load[] = { 0x22, 0xac };
 106
 107 #define PID_LOOP_COUNT          1
 108 static const u8 pidff_effect_operation[] = { 0x22, 0x7c };
 109
 110 static const u8 pidff_block_free[] = { 0x22 };
 111
 112 #define PID_DEVICE_GAIN_FIELD   0
 113 static const u8 pidff_device_gain[] = { 0x7e };
 114
 115 #define PID_RAM_POOL_SIZE       0
 116 #define PID_SIMULTANEOUS_MAX    1
 117 #define PID_DEVICE_MANAGED_POOL 2
 118 static const u8 pidff_pool[] = { 0x80, 0x83, 0xa9 };
 119
 120 /* Special field key tables used to put special field keys into arrays */
 121
 122 #define PID_ENABLE_ACTUATORS    0
 123 #define PID_RESET               1
 124 static const u8 pidff_device_control[] = { 0x97, 0x9a };
 125
 126 #define PID_CONSTANT    0
 127 #define PID_RAMP        1
 128 #define PID_SQUARE      2
 129 #define PID_SINE        3
 130 #define PID_TRIANGLE    4
 131 #define PID_SAW_UP      5
 132 #define PID_SAW_DOWN    6
 133 #define PID_SPRING      7
 134 #define PID_DAMPER      8
 135 #define PID_INERTIA     9
 136 #define PID_FRICTION    10
 137 static const u8 pidff_effect_types[] = {
 138         0x26, 0x27, 0x30, 0x31, 0x32, 0x33, 0x34,
 139         0x40, 0x41, 0x42, 0x43
 140 };
 141
 142 #define PID_BLOCK_LOAD_SUCCESS  0
 143 #define PID_BLOCK_LOAD_FULL     1
 144 static const u8 pidff_block_load_status[] = { 0x8c, 0x8d };
 145
 146 #define PID_EFFECT_START        0
 147 #define PID_EFFECT_STOP         1
 148 static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };
 149
 150 struct pidff_usage {
 151         struct hid_field *field;
 152         s32 *value;
 153 };
 154
 155 struct pidff_device {
 156         struct hid_device *hid;
 157
 158         struct hid_report *reports[sizeof(pidff_reports)];
 159
 160         struct pidff_usage set_effect[sizeof(pidff_set_effect)];
 161         struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
 162         struct pidff_usage set_condition[sizeof(pidff_set_condition)];
 163         struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
 164         struct pidff_usage set_constant[sizeof(pidff_set_constant)];
 165         struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];
 166
 167         struct pidff_usage device_gain[sizeof(pidff_device_gain)];
 168         struct pidff_usage block_load[sizeof(pidff_block_load)];
 169         struct pidff_usage pool[sizeof(pidff_pool)];
 170         struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
 171         struct pidff_usage block_free[sizeof(pidff_block_free)];
 172
 173         /* Special field is a field that is not composed of
 174            usage<->value pairs that pidff_usage values are */
 175
 176         /* Special field in create_new_effect */
 177         struct hid_field *create_new_effect_type;
 178
 179         /* Special fields in set_effect */
 180         struct hid_field *set_effect_type;
 181         struct hid_field *effect_direction;
 182
 183         /* Special field in device_control */
 184         struct hid_field *device_control;
 185
 186         /* Special field in block_load */
 187         struct hid_field *block_load_status;
 188
 189         /* Special field in effect_operation */
 190         struct hid_field *effect_operation_status;
 191
 192         int control_id[sizeof(pidff_device_control)];
 193         int type_id[sizeof(pidff_effect_types)];
 194         int status_id[sizeof(pidff_block_load_status)];
 195         int operation_id[sizeof(pidff_effect_operation_status)];
 196
 197         int pid_id[PID_EFFECTS_MAX];
 198 };
 199
 200 /*
 201  * Scale an unsigned value with range 0..max for the given field
 202  */
 203 static int pidff_rescale(int i, int max, struct hid_field *field)
 204 {
 205         return i * (field->logical_maximum - field->logical_minimum) / max +
 206             field->logical_minimum;
 207 }
 208
 209 /*
 210  * Scale a signed value in range -0x8000..0x7fff for the given field
 211  */
 212 static int pidff_rescale_signed(int i, struct hid_field *field)
 213 {
 214         return i == 0 ? 0 : i >
 215             0 ? i * field->logical_maximum / 0x7fff : i *
 216             field->logical_minimum / -0x8000;
 217 }
 218
 219 static void pidff_set(struct pidff_usage *usage, u16 value)
 220 {
 221         usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
 222         debug("calculated from %d to %d", value, usage->value[0]);
 223 }
 224
 225 static void pidff_set_signed(struct pidff_usage *usage, s16 value)
 226 {
 227         if (usage->field->logical_minimum < 0)
 228                 usage->value[0] = pidff_rescale_signed(value, usage->field);
 229         else {
 230                 if (value < 0)
 231                         usage->value[0] =
 232                             pidff_rescale(-value, 0x8000, usage->field);
 233                 else
 234                         usage->value[0] =
 235                             pidff_rescale(value, 0x7fff, usage->field);
 236         }
 237         debug("calculated from %d to %d", value, usage->value[0]);
 238 }
 239
 240 /*
 241  * Send envelope report to the device
 242  */
 243 static void pidff_set_envelope_report(struct pidff_device *pidff,
 244                                       struct ff_envelope *envelope)
 245 {
 246         pidff->set_envelope[PID_EFFECT_BLOCK_INDEX].value[0] =
 247             pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 248
 249         pidff->set_envelope[PID_ATTACK_LEVEL].value[0] =
 250             pidff_rescale(envelope->attack_level >
 251                           0x7fff ? 0x7fff : envelope->attack_level, 0x7fff,
 252                           pidff->set_envelope[PID_ATTACK_LEVEL].field);
 253         pidff->set_envelope[PID_FADE_LEVEL].value[0] =
 254             pidff_rescale(envelope->fade_level >
 255                           0x7fff ? 0x7fff : envelope->fade_level, 0x7fff,
 256                           pidff->set_envelope[PID_FADE_LEVEL].field);
 257
 258         pidff->set_envelope[PID_ATTACK_TIME].value[0] = envelope->attack_length;
 259         pidff->set_envelope[PID_FADE_TIME].value[0] = envelope->fade_length;
 260
 261         debug("attack %u => %d", envelope->attack_level,
 262               pidff->set_envelope[PID_ATTACK_LEVEL].value[0]);
 263
 264         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_ENVELOPE],
 265                           USB_DIR_OUT);
 266 }
 267
 268 /*
 269  * Test if the new envelope differs from old one
 270  */
 271 static int pidff_needs_set_envelope(struct ff_envelope *envelope,
 272                                     struct ff_envelope *old)
 273 {
 274         return envelope->attack_level != old->attack_level ||
 275                envelope->fade_level != old->fade_level ||
 276                envelope->attack_length != old->attack_length ||
 277                envelope->fade_length != old->fade_length;
 278 }
 279
 280 /*
 281  * Send constant force report to the device
 282  */
 283 static void pidff_set_constant_force_report(struct pidff_device *pidff,
 284                                             struct ff_effect *effect)
 285 {
 286         pidff->set_constant[PID_EFFECT_BLOCK_INDEX].value[0] =
 287                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 288         pidff_set_signed(&pidff->set_constant[PID_MAGNITUDE],
 289                          effect->u.constant.level);
 290
 291         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONSTANT],
 292                           USB_DIR_OUT);
 293 }
 294
 295 /*
 296  * Test if the constant parameters have changed between effects
 297  */
 298 static int pidff_needs_set_constant(struct ff_effect *effect,
 299                                     struct ff_effect *old)
 300 {
 301         return effect->u.constant.level != old->u.constant.level;
 302 }
 303
 304 /*
 305  * Send set effect report to the device
 306  */
 307 static void pidff_set_effect_report(struct pidff_device *pidff,
 308                                     struct ff_effect *effect)
 309 {
 310         pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
 311                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 312         pidff->set_effect_type->value[0] =
 313                 pidff->create_new_effect_type->value[0];
 314         pidff->set_effect[PID_DURATION].value[0] = effect->replay.length;
 315         pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
 316         pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] =
 317                 effect->trigger.interval;
 318         pidff->set_effect[PID_GAIN].value[0] =
 319                 pidff->set_effect[PID_GAIN].field->logical_maximum;
 320         pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
 321         pidff->effect_direction->value[0] =
 322                 pidff_rescale(effect->direction, 0xffff,
 323                                 pidff->effect_direction);
 324         pidff->set_effect[PID_START_DELAY].value[0] = effect->replay.delay;
 325
 326         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
 327                           USB_DIR_OUT);
 328 }
 329
 330 /*
 331  * Test if the values used in set_effect have changed
 332  */
 333 static int pidff_needs_set_effect(struct ff_effect *effect,
 334                                   struct ff_effect *old)
 335 {
 336         return effect->replay.length != old->replay.length ||
 337                effect->trigger.interval != old->trigger.interval ||
 338                effect->trigger.button != old->trigger.button ||
 339                effect->direction != old->direction ||
 340                effect->replay.delay != old->replay.delay;
 341 }
 342
 343 /*
 344  * Send periodic effect report to the device
 345  */
 346 static void pidff_set_periodic_report(struct pidff_device *pidff,
 347                                       struct ff_effect *effect)
 348 {
 349         pidff->set_periodic[PID_EFFECT_BLOCK_INDEX].value[0] =
 350                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 351         pidff_set_signed(&pidff->set_periodic[PID_MAGNITUDE],
 352                          effect->u.periodic.magnitude);
 353         pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
 354                          effect->u.periodic.offset);
 355         pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
 356         pidff->set_periodic[PID_PERIOD].value[0] = effect->u.periodic.period;
 357
 358         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_PERIODIC],
 359                           USB_DIR_OUT);
 360
 361 }
 362
 363 /*
 364  * Test if periodic effect parameters have changed
 365  */
 366 static int pidff_needs_set_periodic(struct ff_effect *effect,
 367                                     struct ff_effect *old)
 368 {
 369         return effect->u.periodic.magnitude != old->u.periodic.magnitude ||
 370                effect->u.periodic.offset != old->u.periodic.offset ||
 371                effect->u.periodic.phase != old->u.periodic.phase ||
 372                effect->u.periodic.period != old->u.periodic.period;
 373 }
 374
 375 /*
 376  * Send condition effect reports to the device
 377  */
 378 static void pidff_set_condition_report(struct pidff_device *pidff,
 379                                        struct ff_effect *effect)
 380 {
 381         int i;
 382
 383         pidff->set_condition[PID_EFFECT_BLOCK_INDEX].value[0] =
 384                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 385
 386         for (i = 0; i < 2; i++) {
 387                 pidff->set_condition[PID_PARAM_BLOCK_OFFSET].value[0] = i;
 388                 pidff_set_signed(&pidff->set_condition[PID_CP_OFFSET],
 389                                  effect->u.condition[i].center);
 390                 pidff_set_signed(&pidff->set_condition[PID_POS_COEFFICIENT],
 391                                  effect->u.condition[i].right_coeff);
 392                 pidff_set_signed(&pidff->set_condition[PID_NEG_COEFFICIENT],
 393                                  effect->u.condition[i].left_coeff);
 394                 pidff_set(&pidff->set_condition[PID_POS_SATURATION],
 395                           effect->u.condition[i].right_saturation);
 396                 pidff_set(&pidff->set_condition[PID_NEG_SATURATION],
 397                           effect->u.condition[i].left_saturation);
 398                 pidff_set(&pidff->set_condition[PID_DEAD_BAND],
 399                           effect->u.condition[i].deadband);
 400                 usbhid_wait_io(pidff->hid);
 401                 usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONDITION],
 402                                   USB_DIR_OUT);
 403         }
 404 }
 405
 406 /*
 407  * Test if condition effect parameters have changed
 408  */
 409 static int pidff_needs_set_condition(struct ff_effect *effect,
 410                                      struct ff_effect *old)
 411 {
 412         int i;
 413         int ret = 0;
 414
 415         for (i = 0; i < 2; i++) {
 416                 struct ff_condition_effect *cond = &effect->u.condition[i];
 417                 struct ff_condition_effect *old_cond = &old->u.condition[i];
 418
 419                 ret |= cond->center != old_cond->center ||
 420                        cond->right_coeff != old_cond->right_coeff ||
 421                        cond->left_coeff != old_cond->left_coeff ||
 422                        cond->right_saturation != old_cond->right_saturation ||
 423                        cond->left_saturation != old_cond->left_saturation ||
 424                        cond->deadband != old_cond->deadband;
 425         }
 426
 427         return ret;
 428 }
 429
 430 /*
 431  * Send ramp force report to the device
 432  */
 433 static void pidff_set_ramp_force_report(struct pidff_device *pidff,
 434                                         struct ff_effect *effect)
 435 {
 436         pidff->set_ramp[PID_EFFECT_BLOCK_INDEX].value[0] =
 437                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 438         pidff_set_signed(&pidff->set_ramp[PID_RAMP_START],
 439                          effect->u.ramp.start_level);
 440         pidff_set_signed(&pidff->set_ramp[PID_RAMP_END],
 441                          effect->u.ramp.end_level);
 442         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_RAMP],
 443                           USB_DIR_OUT);
 444 }
 445
 446 /*
 447  * Test if ramp force parameters have changed
 448  */
 449 static int pidff_needs_set_ramp(struct ff_effect *effect, struct ff_effect *old)
 450 {
 451         return effect->u.ramp.start_level != old->u.ramp.start_level ||
 452                effect->u.ramp.end_level != old->u.ramp.end_level;
 453 }
 454
 455 /*
 456  * Send a request for effect upload to the device
 457  *
 458  * Returns 0 if device reported success, -ENOSPC if the device reported memory
 459  * is full. Upon unknown response the function will retry for 60 times, if
 460  * still unsuccessful -EIO is returned.
 461  */
 462 static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
 463 {
 464         int j;
 465
 466         pidff->create_new_effect_type->value[0] = efnum;
 467         usbhid_submit_report(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
 468                           USB_DIR_OUT);
 469         debug("create_new_effect sent, type: %d", efnum);
 470
 471         pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
 472         pidff->block_load_status->value[0] = 0;
 473         usbhid_wait_io(pidff->hid);
 474
 475         for (j = 0; j < 60; j++) {
 476                 debug("pid_block_load requested");
 477                 usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
 478                                   USB_DIR_IN);
 479                 usbhid_wait_io(pidff->hid);
 480                 if (pidff->block_load_status->value[0] ==
 481                     pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
 482                         debug("device reported free memory: %d bytes",
 483                               pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
 484                                 pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
 485                         return 0;
 486                 }
 487                 if (pidff->block_load_status->value[0] ==
 488                     pidff->status_id[PID_BLOCK_LOAD_FULL]) {
 489                         debug("not enough memory free: %d bytes",
 490                               pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
 491                                 pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
 492                         return -ENOSPC;
 493                 }
 494         }
 495         printk(KERN_ERR "hid-pidff: pid_block_load failed 60 times\n");
 496         return -EIO;
 497 }
 498
 499 /*
 500  * Play the effect with PID id n times
 501  */
 502 static void pidff_playback_pid(struct pidff_device *pidff, int pid_id, int n)
 503 {
 504         pidff->effect_operation[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
 505
 506         if (n == 0) {
 507                 pidff->effect_operation_status->value[0] =
 508                         pidff->operation_id[PID_EFFECT_STOP];
 509         } else {
 510                 pidff->effect_operation_status->value[0] =
 511                         pidff->operation_id[PID_EFFECT_START];
 512                 pidff->effect_operation[PID_LOOP_COUNT].value[0] = n;
 513         }
 514
 515         usbhid_wait_io(pidff->hid);
 516         usbhid_submit_report(pidff->hid, pidff->reports[PID_EFFECT_OPERATION],
 517                           USB_DIR_OUT);
 518 }
 519
 520 /**
 521  * Play the effect with effect id @effect_id for @value times
 522  */
 523 static int pidff_playback(struct input_dev *dev, int effect_id, int value)
 524 {
 525         struct pidff_device *pidff = dev->ff->private;
 526
 527         pidff_playback_pid(pidff, pidff->pid_id[effect_id], value);
 528
 529         return 0;
 530 }
 531
 532 /*
 533  * Erase effect with PID id
 534  */
 535 static void pidff_erase_pid(struct pidff_device *pidff, int pid_id)
 536 {
 537         pidff->block_free[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
 538         usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_FREE],
 539                           USB_DIR_OUT);
 540 }
 541
 542 /*
 543  * Stop and erase effect with effect_id
 544  */
 545 static int pidff_erase_effect(struct input_dev *dev, int effect_id)
 546 {
 547         struct pidff_device *pidff = dev->ff->private;
 548         int pid_id = pidff->pid_id[effect_id];
 549
 550         debug("starting to erase %d/%d", effect_id, pidff->pid_id[effect_id]);
 551         pidff_playback_pid(pidff, pid_id, 0);
 552         pidff_erase_pid(pidff, pid_id);
 553
 554         return 0;
 555 }
 556
 557 /*
 558  * Effect upload handler
 559  */
 560 static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
 561                                struct ff_effect *old)
 562 {
 563         struct pidff_device *pidff = dev->ff->private;
 564         int type_id;
 565         int error;
 566
 567         switch (effect->type) {
 568         case FF_CONSTANT:
 569                 if (!old) {
 570                         error = pidff_request_effect_upload(pidff,
 571                                         pidff->type_id[PID_CONSTANT]);
 572                         if (error)
 573                                 return error;
 574                 }
 575                 if (!old || pidff_needs_set_effect(effect, old))
 576                         pidff_set_effect_report(pidff, effect);
 577                 if (!old || pidff_needs_set_constant(effect, old))
 578                         pidff_set_constant_force_report(pidff, effect);
 579                 if (!old ||
 580                     pidff_needs_set_envelope(&effect->u.constant.envelope,
 581                                         &old->u.constant.envelope))
 582                         pidff_set_envelope_report(pidff,
 583                                         &effect->u.constant.envelope);
 584                 break;
 585
 586         case FF_PERIODIC:
 587                 if (!old) {
 588                         switch (effect->u.periodic.waveform) {
 589                         case FF_SQUARE:
 590                                 type_id = PID_SQUARE;
 591                                 break;
 592                         case FF_TRIANGLE:
 593                                 type_id = PID_TRIANGLE;
 594                                 break;
 595                         case FF_SINE:
 596                                 type_id = PID_SINE;
 597                                 break;
 598                         case FF_SAW_UP:
 599                                 type_id = PID_SAW_UP;
 600                                 break;
 601                         case FF_SAW_DOWN:
 602                                 type_id = PID_SAW_DOWN;
 603                                 break;
 604                         default:
 605                                 printk(KERN_ERR
 606                                        "hid-pidff: invalid waveform\n");
 607                                 return -EINVAL;
 608                         }
 609
 610                         error = pidff_request_effect_upload(pidff,
 611                                         pidff->type_id[type_id]);
 612                         if (error)
 613                                 return error;
 614                 }
 615                 if (!old || pidff_needs_set_effect(effect, old))
 616                         pidff_set_effect_report(pidff, effect);
 617                 if (!old || pidff_needs_set_periodic(effect, old))
 618                         pidff_set_periodic_report(pidff, effect);
 619                 if (!old ||
 620                     pidff_needs_set_envelope(&effect->u.periodic.envelope,
 621                                         &old->u.periodic.envelope))
 622                         pidff_set_envelope_report(pidff,
 623                                         &effect->u.periodic.envelope);
 624                 break;
 625
 626         case FF_RAMP:
 627                 if (!old) {
 628                         error = pidff_request_effect_upload(pidff,
 629                                         pidff->type_id[PID_RAMP]);
 630                         if (error)
 631                                 return error;
 632                 }
 633                 if (!old || pidff_needs_set_effect(effect, old))
 634                         pidff_set_effect_report(pidff, effect);
 635                 if (!old || pidff_needs_set_ramp(effect, old))
 636                         pidff_set_ramp_force_report(pidff, effect);
 637                 if (!old ||
 638                     pidff_needs_set_envelope(&effect->u.ramp.envelope,
 639                                         &old->u.ramp.envelope))
 640                         pidff_set_envelope_report(pidff,
 641                                         &effect->u.ramp.envelope);
 642                 break;
 643
 644         case FF_SPRING:
 645                 if (!old) {
 646                         error = pidff_request_effect_upload(pidff,
 647                                         pidff->type_id[PID_SPRING]);
 648                         if (error)
 649                                 return error;
 650                 }
 651                 if (!old || pidff_needs_set_effect(effect, old))
 652                         pidff_set_effect_report(pidff, effect);
 653                 if (!old || pidff_needs_set_condition(effect, old))
 654                         pidff_set_condition_report(pidff, effect);
 655                 break;
 656
 657         case FF_FRICTION:
 658                 if (!old) {
 659                         error = pidff_request_effect_upload(pidff,
 660                                         pidff->type_id[PID_FRICTION]);
 661                         if (error)
 662                                 return error;
 663                 }
 664                 if (!old || pidff_needs_set_effect(effect, old))
 665                         pidff_set_effect_report(pidff, effect);
 666                 if (!old || pidff_needs_set_condition(effect, old))
 667                         pidff_set_condition_report(pidff, effect);
 668                 break;
 669
 670         case FF_DAMPER:
 671                 if (!old) {
 672                         error = pidff_request_effect_upload(pidff,
 673                                         pidff->type_id[PID_DAMPER]);
 674                         if (error)
 675                                 return error;
 676                 }
 677                 if (!old || pidff_needs_set_effect(effect, old))
 678                         pidff_set_effect_report(pidff, effect);
 679                 if (!old || pidff_needs_set_condition(effect, old))
 680                         pidff_set_condition_report(pidff, effect);
 681                 break;
 682
 683         case FF_INERTIA:
 684                 if (!old) {
 685                         error = pidff_request_effect_upload(pidff,
 686                                         pidff->type_id[PID_INERTIA]);
 687                         if (error)
 688                                 return error;
 689                 }
 690                 if (!old || pidff_needs_set_effect(effect, old))
 691                         pidff_set_effect_report(pidff, effect);
 692                 if (!old || pidff_needs_set_condition(effect, old))
 693                         pidff_set_condition_report(pidff, effect);
 694                 break;
 695
 696         default:
 697                 printk(KERN_ERR "hid-pidff: invalid type\n");
 698                 return -EINVAL;
 699         }
 700
 701         if (!old)
 702                 pidff->pid_id[effect->id] =
 703                     pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 704
 705         debug("uploaded");
 706
 707         return 0;
 708 }
 709
 710 /*
 711  * set_gain() handler
 712  */
 713 static void pidff_set_gain(struct input_dev *dev, u16 gain)
 714 {
 715         struct pidff_device *pidff = dev->ff->private;
 716
 717         pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
 718         usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
 719                           USB_DIR_OUT);
 720 }
 721
 722 static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
 723 {
 724         struct hid_field *field =
 725                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;
 726
 727         if (!magnitude) {
 728                 pidff_playback_pid(pidff, field->logical_minimum, 0);
 729                 return;
 730         }
 731
 732         pidff_playback_pid(pidff, field->logical_minimum, 1);
 733
 734         pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
 735                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
 736         pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
 737         pidff->set_effect[PID_DURATION].value[0] = 0;
 738         pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
 739         pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
 740         pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
 741         pidff->set_effect[PID_START_DELAY].value[0] = 0;
 742
 743         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
 744                           USB_DIR_OUT);
 745 }
 746
 747 /*
 748  * pidff_set_autocenter() handler
 749  */
 750 static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
 751 {
 752         struct pidff_device *pidff = dev->ff->private;
 753
 754         pidff_autocenter(pidff, magnitude);
 755 }
 756
 757 /*
 758  * Find fields from a report and fill a pidff_usage
 759  */
 760 static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
 761                              struct hid_report *report, int count, int strict)
 762 {
 763         int i, j, k, found;
 764
 765         for (k = 0; k < count; k++) {
 766                 found = 0;
 767                 for (i = 0; i < report->maxfield; i++) {
 768                         if (report->field[i]->maxusage !=
 769                             report->field[i]->report_count) {
 770                                 debug("maxusage and report_count do not match, "
 771                                       "skipping");
 772                                 continue;
 773                         }
 774                         for (j = 0; j < report->field[i]->maxusage; j++) {
 775                                 if (report->field[i]->usage[j].hid ==
 776                                     (HID_UP_PID | table[k])) {
 777                                         debug("found %d at %d->%d", k, i, j);
 778                                         usage[k].field = report->field[i];
 779                                         usage[k].value =
 780                                                 &report->field[i]->value[j];
 781                                         found = 1;
 782                                         break;
 783                                 }
 784                         }
 785                         if (found)
 786                                 break;
 787                 }
 788                 if (!found && strict) {
 789                         debug("failed to locate %d", k);
 790                         return -1;
 791                 }
 792         }
 793         return 0;
 794 }
 795
 796 /*
 797  * Return index into pidff_reports for the given usage
 798  */
 799 static int pidff_check_usage(int usage)
 800 {
 801         int i;
 802
 803         for (i = 0; i < sizeof(pidff_reports); i++)
 804                 if (usage == (HID_UP_PID | pidff_reports[i]))
 805                         return i;
 806
 807         return -1;
 808 }
 809
 810 /*
 811  * Find the reports and fill pidff->reports[]
 812  * report_type specifies either OUTPUT or FEATURE reports
 813  */
 814 static void pidff_find_reports(struct hid_device *hid, int report_type,
 815                                struct pidff_device *pidff)
 816 {
 817         struct hid_report *report;
 818         int i, ret;
 819
 820         list_for_each_entry(report,
 821                             &hid->report_enum[report_type].report_list, list) {
 822                 if (report->maxfield < 1)
 823                         continue;
 824                 ret = pidff_check_usage(report->field[0]->logical);
 825                 if (ret != -1) {
 826                         debug("found usage 0x%02x from field->logical",
 827                               pidff_reports[ret]);
 828                         pidff->reports[ret] = report;
 829                         continue;
 830                 }
 831
 832                 /*
 833                  * Sometimes logical collections are stacked to indicate
 834                  * different usages for the report and the field, in which
 835                  * case we want the usage of the parent. However, Linux HID
 836                  * implementation hides this fact, so we have to dig it up
 837                  * ourselves
 838                  */
 839                 i = report->field[0]->usage[0].collection_index;
 840                 if (i <= 0 ||
 841                     hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
 842                         continue;
 843                 ret = pidff_check_usage(hid->collection[i - 1].usage);
 844                 if (ret != -1 && !pidff->reports[ret]) {
 845                         debug("found usage 0x%02x from collection array",
 846                               pidff_reports[ret]);
 847                         pidff->reports[ret] = report;
 848                 }
 849         }
 850 }
 851
 852 /*
 853  * Test if the required reports have been found
 854  */
 855 static int pidff_reports_ok(struct pidff_device *pidff)
 856 {
 857         int i;
 858
 859         for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
 860                 if (!pidff->reports[i]) {
 861                         debug("%d missing", i);
 862                         return 0;
 863                 }
 864         }
 865
 866         return 1;
 867 }
 868
 869 /*
 870  * Find a field with a specific usage within a report
 871  */
 872 static struct hid_field *pidff_find_special_field(struct hid_report *report,
 873                                                   int usage, int enforce_min)
 874 {
 875         int i;
 876
 877         for (i = 0; i < report->maxfield; i++) {
 878                 if (report->field[i]->logical == (HID_UP_PID | usage) &&
 879                     report->field[i]->report_count > 0) {
 880                         if (!enforce_min ||
 881                             report->field[i]->logical_minimum == 1)
 882                                 return report->field[i];
 883                         else {
 884                                 printk(KERN_ERR "hid-pidff: logical_minimum "
 885                                         "is not 1 as it should be\n");
 886                                 return NULL;
 887                         }
 888                 }
 889         }
 890         return NULL;
 891 }
 892
 893 /*
 894  * Fill a pidff->*_id struct table
 895  */
 896 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
 897                                    const u8 *usagetable, int count)
 898 {
 899
 900         int i, j;
 901         int found = 0;
 902
 903         for (i = 0; i < count; i++) {
 904                 for (j = 0; j < fld->maxusage; j++) {
 905                         if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
 906                                 keys[i] = j + 1;
 907                                 found++;
 908                                 break;
 909                         }
 910                 }
 911         }
 912         return found;
 913 }
 914
 915 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
 916         pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
 917                 sizeof(pidff_ ## name))
 918
 919 /*
 920  * Find and check the special fields
 921  */
 922 static int pidff_find_special_fields(struct pidff_device *pidff)
 923 {
 924         debug("finding special fields");
 925
 926         pidff->create_new_effect_type =
 927                 pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
 928                                          0x25, 1);
 929         pidff->set_effect_type =
 930                 pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 931                                          0x25, 1);
 932         pidff->effect_direction =
 933                 pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 934                                          0x57, 0);
 935         pidff->device_control =
 936                 pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
 937                                          0x96, 1);
 938         pidff->block_load_status =
 939                 pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
 940                                          0x8b, 1);
 941         pidff->effect_operation_status =
 942                 pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
 943                                          0x78, 1);
 944
 945         debug("search done");
 946
 947         if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
 948                 printk(KERN_ERR "hid-pidff: effect lists not found\n");
 949                 return -1;
 950         }
 951
 952         if (!pidff->effect_direction) {
 953                 printk(KERN_ERR "hid-pidff: direction field not found\n");
 954                 return -1;
 955         }
 956
 957         if (!pidff->device_control) {
 958                 printk(KERN_ERR "hid-pidff: device control field not found\n");
 959                 return -1;
 960         }
 961
 962         if (!pidff->block_load_status) {
 963                 printk(KERN_ERR
 964                        "hid-pidff: block load status field not found\n");
 965                 return -1;
 966         }
 967
 968         if (!pidff->effect_operation_status) {
 969                 printk(KERN_ERR
 970                        "hid-pidff: effect operation field not found\n");
 971                 return -1;
 972         }
 973
 974         pidff_find_special_keys(pidff->control_id, pidff->device_control,
 975                                 pidff_device_control,
 976                                 sizeof(pidff_device_control));
 977
 978         PIDFF_FIND_SPECIAL_KEYS(control_id, device_control, device_control);
 979
 980         if (!PIDFF_FIND_SPECIAL_KEYS(type_id, create_new_effect_type,
 981                                      effect_types)) {
 982                 printk(KERN_ERR "hid-pidff: no effect types found\n");
 983                 return -1;
 984         }
 985
 986         if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
 987                                     block_load_status) !=
 988                         sizeof(pidff_block_load_status)) {
 989                 printk(KERN_ERR
 990                        "hidpidff: block load status identifiers not found\n");
 991                 return -1;
 992         }
 993
 994         if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
 995                                     effect_operation_status) !=
 996                         sizeof(pidff_effect_operation_status)) {
 997                 printk(KERN_ERR
 998                        "hidpidff: effect operation identifiers not found\n");
 999                 return -1;
1000         }
1001
1002         return 0;
1003 }
1004
1005 /**
1006  * Find the implemented effect types
1007  */
1008 static int pidff_find_effects(struct pidff_device *pidff,
1009                               struct input_dev *dev)
1010 {
1011         int i;
1012
1013         for (i = 0; i < sizeof(pidff_effect_types); i++) {
1014                 int pidff_type = pidff->type_id[i];
1015                 if (pidff->set_effect_type->usage[pidff_type].hid !=
1016                     pidff->create_new_effect_type->usage[pidff_type].hid) {
1017                         printk(KERN_ERR "hid-pidff: "
1018                                "effect type number %d is invalid\n", i);
1019                         return -1;
1020                 }
1021         }
1022
1023         if (pidff->type_id[PID_CONSTANT])
1024                 set_bit(FF_CONSTANT, dev->ffbit);
1025         if (pidff->type_id[PID_RAMP])
1026                 set_bit(FF_RAMP, dev->ffbit);
1027         if (pidff->type_id[PID_SQUARE]) {
1028                 set_bit(FF_SQUARE, dev->ffbit);
1029                 set_bit(FF_PERIODIC, dev->ffbit);
1030         }
1031         if (pidff->type_id[PID_SINE]) {
1032                 set_bit(FF_SINE, dev->ffbit);
1033                 set_bit(FF_PERIODIC, dev->ffbit);
1034         }
1035         if (pidff->type_id[PID_TRIANGLE]) {
1036                 set_bit(FF_TRIANGLE, dev->ffbit);
1037                 set_bit(FF_PERIODIC, dev->ffbit);
1038         }
1039         if (pidff->type_id[PID_SAW_UP]) {
1040                 set_bit(FF_SAW_UP, dev->ffbit);
1041                 set_bit(FF_PERIODIC, dev->ffbit);
1042         }
1043         if (pidff->type_id[PID_SAW_DOWN]) {
1044                 set_bit(FF_SAW_DOWN, dev->ffbit);
1045                 set_bit(FF_PERIODIC, dev->ffbit);
1046         }
1047         if (pidff->type_id[PID_SPRING])
1048                 set_bit(FF_SPRING, dev->ffbit);
1049         if (pidff->type_id[PID_DAMPER])
1050                 set_bit(FF_DAMPER, dev->ffbit);
1051         if (pidff->type_id[PID_INERTIA])
1052                 set_bit(FF_INERTIA, dev->ffbit);
1053         if (pidff->type_id[PID_FRICTION])
1054                 set_bit(FF_FRICTION, dev->ffbit);
1055
1056         return 0;
1057
1058 }
1059
1060 #define PIDFF_FIND_FIELDS(name, report, strict) \
1061         pidff_find_fields(pidff->name, pidff_ ## name, \
1062                 pidff->reports[report], \
1063                 sizeof(pidff_ ## name), strict)
1064
1065 /*
1066  * Fill and check the pidff_usages
1067  */
1068 static int pidff_init_fields(struct pidff_device *pidff, struct input_dev *dev)
1069 {
1070         int envelope_ok = 0;
1071
1072         if (PIDFF_FIND_FIELDS(set_effect, PID_SET_EFFECT, 1)) {
1073                 printk(KERN_ERR
1074                        "hid-pidff: unknown set_effect report layout\n");
1075                 return -ENODEV;
1076         }
1077
1078         PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
1079         if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
1080                 printk(KERN_ERR
1081                        "hid-pidff: unknown pid_block_load report layout\n");
1082                 return -ENODEV;
1083         }
1084
1085         if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
1086                 printk(KERN_ERR
1087                        "hid-pidff: unknown effect_operation report layout\n");
1088                 return -ENODEV;
1089         }
1090
1091         if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
1092                 printk(KERN_ERR
1093                        "hid-pidff: unknown pid_block_free report layout\n");
1094                 return -ENODEV;
1095         }
1096
1097         if (!PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1))
1098                 envelope_ok = 1;
1099
1100         if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
1101                 return -ENODEV;
1102
1103         if (!envelope_ok) {
1104                 if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
1105                         printk(KERN_WARNING "hid-pidff: "
1106                                "has constant effect but no envelope\n");
1107                 if (test_and_clear_bit(FF_RAMP, dev->ffbit))
1108                         printk(KERN_WARNING "hid-pidff: "
1109                                 "has ramp effect but no envelope\n");
1110
1111                 if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
1112                         printk(KERN_WARNING "hid-pidff: "
1113                                 "has periodic effect but no envelope\n");
1114         }
1115
1116         if (test_bit(FF_CONSTANT, dev->ffbit) &&
1117             PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
1118                 printk(KERN_WARNING
1119                        "hid-pidff: unknown constant effect layout\n");
1120                 clear_bit(FF_CONSTANT, dev->ffbit);
1121         }
1122
1123         if (test_bit(FF_RAMP, dev->ffbit) &&
1124             PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
1125                 printk(KERN_WARNING "hid-pidff: unknown ramp effect layout\n");
1126                 clear_bit(FF_RAMP, dev->ffbit);
1127         }
1128
1129         if ((test_bit(FF_SPRING, dev->ffbit) ||
1130              test_bit(FF_DAMPER, dev->ffbit) ||
1131              test_bit(FF_FRICTION, dev->ffbit) ||
1132              test_bit(FF_INERTIA, dev->ffbit)) &&
1133             PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1)) {
1134                 printk(KERN_WARNING
1135                        "hid-pidff: unknown condition effect layout\n");
1136                 clear_bit(FF_SPRING, dev->ffbit);
1137                 clear_bit(FF_DAMPER, dev->ffbit);
1138                 clear_bit(FF_FRICTION, dev->ffbit);
1139                 clear_bit(FF_INERTIA, dev->ffbit);
1140         }
1141
1142         if (test_bit(FF_PERIODIC, dev->ffbit) &&
1143             PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
1144                 printk(KERN_WARNING
1145                        "hid-pidff: unknown periodic effect layout\n");
1146                 clear_bit(FF_PERIODIC, dev->ffbit);
1147         }
1148
1149         PIDFF_FIND_FIELDS(pool, PID_POOL, 0);
1150
1151         if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
1152                 set_bit(FF_GAIN, dev->ffbit);
1153
1154         return 0;
1155 }
1156
1157 /*
1158  * Reset the device
1159  */
1160 static void pidff_reset(struct pidff_device *pidff)
1161 {
1162         struct hid_device *hid = pidff->hid;
1163         int i = 0;
1164
1165         pidff->device_control->value[0] = pidff->control_id[PID_RESET];
1166         /* We reset twice as sometimes hid_wait_io isn't waiting long enough */
1167         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1168         usbhid_wait_io(hid);
1169         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1170         usbhid_wait_io(hid);
1171
1172         pidff->device_control->value[0] =
1173                 pidff->control_id[PID_ENABLE_ACTUATORS];
1174         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1175         usbhid_wait_io(hid);
1176
1177         /* pool report is sometimes messed up, refetch it */
1178         usbhid_submit_report(hid, pidff->reports[PID_POOL], USB_DIR_IN);
1179         usbhid_wait_io(hid);
1180
1181         if (pidff->pool[PID_SIMULTANEOUS_MAX].value) {
1182                 int sim_effects = pidff->pool[PID_SIMULTANEOUS_MAX].value[0];
1183                 while (sim_effects < 2) {
1184                         if (i++ > 20) {
1185                                 printk(KERN_WARNING "hid-pidff: device reports "
1186                                        "%d simultaneous effects\n",
1187                                        sim_effects);
1188                                 break;
1189                         }
1190                         debug("pid_pool requested again");
1191                         usbhid_submit_report(hid, pidff->reports[PID_POOL],
1192                                           USB_DIR_IN);
1193                         usbhid_wait_io(hid);
1194                 }
1195         }
1196 }
1197
1198 /*
1199  * Test if autocenter modification is using the supported method
1200  */
1201 static int pidff_check_autocenter(struct pidff_device *pidff,
1202                                   struct input_dev *dev)
1203 {
1204         int error;
1205
1206         /*
1207          * Let's find out if autocenter modification is supported
1208          * Specification doesn't specify anything, so we request an
1209          * effect upload and cancel it immediately. If the approved
1210          * effect id was one above the minimum, then we assume the first
1211          * effect id is a built-in spring type effect used for autocenter
1212          */
1213
1214         error = pidff_request_effect_upload(pidff, 1);
1215         if (error) {
1216                 printk(KERN_ERR "hid-pidff: upload request failed\n");
1217                 return error;
1218         }
1219
1220         if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
1221             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
1222                 pidff_autocenter(pidff, 0xffff);
1223                 set_bit(FF_AUTOCENTER, dev->ffbit);
1224         } else {
1225                 printk(KERN_NOTICE "hid-pidff: "
1226                        "device has unknown autocenter control method\n");
1227         }
1228
1229         pidff_erase_pid(pidff,
1230                         pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);
1231
1232         return 0;
1233
1234 }
1235
1236 /*
1237  * Check if the device is PID and initialize it
1238  */
1239 int hid_pidff_init(struct hid_device *hid)
1240 {
1241         struct pidff_device *pidff;
1242         struct hid_input *hidinput = list_entry(hid->inputs.next,
1243                                                 struct hid_input, list);
1244         struct input_dev *dev = hidinput->input;
1245         struct ff_device *ff;
1246         int max_effects;
1247         int error;
1248
1249         debug("starting pid init");
1250
1251         if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
1252                 debug("not a PID device, no output report");
1253                 return -ENODEV;
1254         }
1255
1256         pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
1257         if (!pidff)
1258                 return -ENOMEM;
1259
1260         pidff->hid = hid;
1261
1262         pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
1263         pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);
1264
1265         if (!pidff_reports_ok(pidff)) {
1266                 debug("reports not ok, aborting");
1267                 error = -ENODEV;
1268                 goto fail;
1269         }
1270
1271         error = pidff_init_fields(pidff, dev);
1272         if (error)
1273                 goto fail;
1274
1275         pidff_reset(pidff);
1276
1277         if (test_bit(FF_GAIN, dev->ffbit)) {
1278                 pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], 0xffff);
1279                 usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
1280                                   USB_DIR_OUT);
1281         }
1282
1283         error = pidff_check_autocenter(pidff, dev);
1284         if (error)
1285                 goto fail;
1286
1287         max_effects =
1288             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
1289             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
1290             1;
1291         debug("max effects is %d", max_effects);
1292
1293         if (max_effects > PID_EFFECTS_MAX)
1294                 max_effects = PID_EFFECTS_MAX;
1295
1296         if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
1297                 debug("max simultaneous effects is %d",
1298                       pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1299
1300         if (pidff->pool[PID_RAM_POOL_SIZE].value)
1301                 debug("device memory size is %d bytes",
1302                       pidff->pool[PID_RAM_POOL_SIZE].value[0]);
1303
1304         if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
1305             pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
1306                 printk(KERN_NOTICE "hid-pidff: "
1307                        "device does not support device managed pool\n");
1308                 goto fail;
1309         }
1310
1311         error = input_ff_create(dev, max_effects);
1312         if (error)
1313                 goto fail;
1314
1315         ff = dev->ff;
1316         ff->private = pidff;
1317         ff->upload = pidff_upload_effect;
1318         ff->erase = pidff_erase_effect;
1319         ff->set_gain = pidff_set_gain;
1320         ff->set_autocenter = pidff_set_autocenter;
1321         ff->playback = pidff_playback;
1322
1323         printk(KERN_INFO "Force feedback for USB HID PID devices by "
1324                "Anssi Hannula <anssi.hannula@gmail.com>\n");
1325
1326         return 0;
1327
1328  fail:
1329         kfree(pidff);
1330         return error;
1331 }