drivers/hid/usbhid/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/slab.h>
  29 #include <linux/usb.h>
  30
  31 #include <linux/hid.h>
  32
  33 #include "usbhid.h"
  34
  35 #define PID_EFFECTS_MAX         64
  36
  37 /* Report usage table used to put reports into an array */
  38
  39 #define PID_SET_EFFECT          0
  40 #define PID_EFFECT_OPERATION    1
  41 #define PID_DEVICE_GAIN         2
  42 #define PID_POOL                3
  43 #define PID_BLOCK_LOAD          4
  44 #define PID_BLOCK_FREE          5
  45 #define PID_DEVICE_CONTROL      6
  46 #define PID_CREATE_NEW_EFFECT   7
  47
  48 #define PID_REQUIRED_REPORTS    7
  49
  50 #define PID_SET_ENVELOPE        8
  51 #define PID_SET_CONDITION       9
  52 #define PID_SET_PERIODIC        10
  53 #define PID_SET_CONSTANT        11
  54 #define PID_SET_RAMP            12
  55 static const u8 pidff_reports[] = {
  56         0x21, 0x77, 0x7d, 0x7f, 0x89, 0x90, 0x96, 0xab,
  57         0x5a, 0x5f, 0x6e, 0x73, 0x74
  58 };
  59
  60 /* device_control is really 0x95, but 0x96 specified as it is the usage of
  61 the only field in that report */
  62
  63 /* Value usage tables used to put fields and values into arrays */
  64
  65 #define PID_EFFECT_BLOCK_INDEX  0
  66
  67 #define PID_DURATION            1
  68 #define PID_GAIN                2
  69 #define PID_TRIGGER_BUTTON      3
  70 #define PID_TRIGGER_REPEAT_INT  4
  71 #define PID_DIRECTION_ENABLE    5
  72 #define PID_START_DELAY         6
  73 static const u8 pidff_set_effect[] = {
  74         0x22, 0x50, 0x52, 0x53, 0x54, 0x56, 0xa7
  75 };
  76
  77 #define PID_ATTACK_LEVEL        1
  78 #define PID_ATTACK_TIME         2
  79 #define PID_FADE_LEVEL          3
  80 #define PID_FADE_TIME           4
  81 static const u8 pidff_set_envelope[] = { 0x22, 0x5b, 0x5c, 0x5d, 0x5e };
  82
  83 #define PID_PARAM_BLOCK_OFFSET  1
  84 #define PID_CP_OFFSET           2
  85 #define PID_POS_COEFFICIENT     3
  86 #define PID_NEG_COEFFICIENT     4
  87 #define PID_POS_SATURATION      5
  88 #define PID_NEG_SATURATION      6
  89 #define PID_DEAD_BAND           7
  90 static const u8 pidff_set_condition[] = {
  91         0x22, 0x23, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65
  92 };
  93
  94 #define PID_MAGNITUDE           1
  95 #define PID_OFFSET              2
  96 #define PID_PHASE               3
  97 #define PID_PERIOD              4
  98 static const u8 pidff_set_periodic[] = { 0x22, 0x70, 0x6f, 0x71, 0x72 };
  99 static const u8 pidff_set_constant[] = { 0x22, 0x70 };
 100
 101 #define PID_RAMP_START          1
 102 #define PID_RAMP_END            2
 103 static const u8 pidff_set_ramp[] = { 0x22, 0x75, 0x76 };
 104
 105 #define PID_RAM_POOL_AVAILABLE  1
 106 static const u8 pidff_block_load[] = { 0x22, 0xac };
 107
 108 #define PID_LOOP_COUNT          1
 109 static const u8 pidff_effect_operation[] = { 0x22, 0x7c };
 110
 111 static const u8 pidff_block_free[] = { 0x22 };
 112
 113 #define PID_DEVICE_GAIN_FIELD   0
 114 static const u8 pidff_device_gain[] = { 0x7e };
 115
 116 #define PID_RAM_POOL_SIZE       0
 117 #define PID_SIMULTANEOUS_MAX    1
 118 #define PID_DEVICE_MANAGED_POOL 2
 119 static const u8 pidff_pool[] = { 0x80, 0x83, 0xa9 };
 120
 121 /* Special field key tables used to put special field keys into arrays */
 122
 123 #define PID_ENABLE_ACTUATORS    0
 124 #define PID_RESET               1
 125 static const u8 pidff_device_control[] = { 0x97, 0x9a };
 126
 127 #define PID_CONSTANT    0
 128 #define PID_RAMP        1
 129 #define PID_SQUARE      2
 130 #define PID_SINE        3
 131 #define PID_TRIANGLE    4
 132 #define PID_SAW_UP      5
 133 #define PID_SAW_DOWN    6
 134 #define PID_SPRING      7
 135 #define PID_DAMPER      8
 136 #define PID_INERTIA     9
 137 #define PID_FRICTION    10
 138 static const u8 pidff_effect_types[] = {
 139         0x26, 0x27, 0x30, 0x31, 0x32, 0x33, 0x34,
 140         0x40, 0x41, 0x42, 0x43
 141 };
 142
 143 #define PID_BLOCK_LOAD_SUCCESS  0
 144 #define PID_BLOCK_LOAD_FULL     1
 145 static const u8 pidff_block_load_status[] = { 0x8c, 0x8d };
 146
 147 #define PID_EFFECT_START        0
 148 #define PID_EFFECT_STOP         1
 149 static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };
 150
 151 struct pidff_usage {
 152         struct hid_field *field;
 153         s32 *value;
 154 };
 155
 156 struct pidff_device {
 157         struct hid_device *hid;
 158
 159         struct hid_report *reports[sizeof(pidff_reports)];
 160
 161         struct pidff_usage set_effect[sizeof(pidff_set_effect)];
 162         struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
 163         struct pidff_usage set_condition[sizeof(pidff_set_condition)];
 164         struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
 165         struct pidff_usage set_constant[sizeof(pidff_set_constant)];
 166         struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];
 167
 168         struct pidff_usage device_gain[sizeof(pidff_device_gain)];
 169         struct pidff_usage block_load[sizeof(pidff_block_load)];
 170         struct pidff_usage pool[sizeof(pidff_pool)];
 171         struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
 172         struct pidff_usage block_free[sizeof(pidff_block_free)];
 173
 174         /* Special field is a field that is not composed of
 175            usage<->value pairs that pidff_usage values are */
 176
 177         /* Special field in create_new_effect */
 178         struct hid_field *create_new_effect_type;
 179
 180         /* Special fields in set_effect */
 181         struct hid_field *set_effect_type;
 182         struct hid_field *effect_direction;
 183
 184         /* Special field in device_control */
 185         struct hid_field *device_control;
 186
 187         /* Special field in block_load */
 188         struct hid_field *block_load_status;
 189
 190         /* Special field in effect_operation */
 191         struct hid_field *effect_operation_status;
 192
 193         int control_id[sizeof(pidff_device_control)];
 194         int type_id[sizeof(pidff_effect_types)];
 195         int status_id[sizeof(pidff_block_load_status)];
 196         int operation_id[sizeof(pidff_effect_operation_status)];
 197
 198         int pid_id[PID_EFFECTS_MAX];
 199 };
 200
 201 /*
 202  * Scale an unsigned value with range 0..max for the given field
 203  */
 204 static int pidff_rescale(int i, int max, struct hid_field *field)
 205 {
 206         return i * (field->logical_maximum - field->logical_minimum) / max +
 207             field->logical_minimum;
 208 }
 209
 210 /*
 211  * Scale a signed value in range -0x8000..0x7fff for the given field
 212  */
 213 static int pidff_rescale_signed(int i, struct hid_field *field)
 214 {
 215         return i == 0 ? 0 : i >
 216             0 ? i * field->logical_maximum / 0x7fff : i *
 217             field->logical_minimum / -0x8000;
 218 }
 219
 220 static void pidff_set(struct pidff_usage *usage, u16 value)
 221 {
 222         usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
 223         debug("calculated from %d to %d", value, usage->value[0]);
 224 }
 225
 226 static void pidff_set_signed(struct pidff_usage *usage, s16 value)
 227 {
 228         if (usage->field->logical_minimum < 0)
 229                 usage->value[0] = pidff_rescale_signed(value, usage->field);
 230         else {
 231                 if (value < 0)
 232                         usage->value[0] =
 233                             pidff_rescale(-value, 0x8000, usage->field);
 234                 else
 235                         usage->value[0] =
 236                             pidff_rescale(value, 0x7fff, usage->field);
 237         }
 238         debug("calculated from %d to %d", value, usage->value[0]);
 239 }
 240
 241 /*
 242  * Send envelope report to the device
 243  */
 244 static void pidff_set_envelope_report(struct pidff_device *pidff,
 245                                       struct ff_envelope *envelope)
 246 {
 247         pidff->set_envelope[PID_EFFECT_BLOCK_INDEX].value[0] =
 248             pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 249
 250         pidff->set_envelope[PID_ATTACK_LEVEL].value[0] =
 251             pidff_rescale(envelope->attack_level >
 252                           0x7fff ? 0x7fff : envelope->attack_level, 0x7fff,
 253                           pidff->set_envelope[PID_ATTACK_LEVEL].field);
 254         pidff->set_envelope[PID_FADE_LEVEL].value[0] =
 255             pidff_rescale(envelope->fade_level >
 256                           0x7fff ? 0x7fff : envelope->fade_level, 0x7fff,
 257                           pidff->set_envelope[PID_FADE_LEVEL].field);
 258
 259         pidff->set_envelope[PID_ATTACK_TIME].value[0] = envelope->attack_length;
 260         pidff->set_envelope[PID_FADE_TIME].value[0] = envelope->fade_length;
 261
 262         debug("attack %u => %d", envelope->attack_level,
 263               pidff->set_envelope[PID_ATTACK_LEVEL].value[0]);
 264
 265         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_ENVELOPE],
 266                           USB_DIR_OUT);
 267 }
 268
 269 /*
 270  * Test if the new envelope differs from old one
 271  */
 272 static int pidff_needs_set_envelope(struct ff_envelope *envelope,
 273                                     struct ff_envelope *old)
 274 {
 275         return envelope->attack_level != old->attack_level ||
 276                envelope->fade_level != old->fade_level ||
 277                envelope->attack_length != old->attack_length ||
 278                envelope->fade_length != old->fade_length;
 279 }
 280
 281 /*
 282  * Send constant force report to the device
 283  */
 284 static void pidff_set_constant_force_report(struct pidff_device *pidff,
 285                                             struct ff_effect *effect)
 286 {
 287         pidff->set_constant[PID_EFFECT_BLOCK_INDEX].value[0] =
 288                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 289         pidff_set_signed(&pidff->set_constant[PID_MAGNITUDE],
 290                          effect->u.constant.level);
 291
 292         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONSTANT],
 293                           USB_DIR_OUT);
 294 }
 295
 296 /*
 297  * Test if the constant parameters have changed between effects
 298  */
 299 static int pidff_needs_set_constant(struct ff_effect *effect,
 300                                     struct ff_effect *old)
 301 {
 302         return effect->u.constant.level != old->u.constant.level;
 303 }
 304
 305 /*
 306  * Send set effect report to the device
 307  */
 308 static void pidff_set_effect_report(struct pidff_device *pidff,
 309                                     struct ff_effect *effect)
 310 {
 311         pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
 312                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 313         pidff->set_effect_type->value[0] =
 314                 pidff->create_new_effect_type->value[0];
 315         pidff->set_effect[PID_DURATION].value[0] = effect->replay.length;
 316         pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
 317         pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] =
 318                 effect->trigger.interval;
 319         pidff->set_effect[PID_GAIN].value[0] =
 320                 pidff->set_effect[PID_GAIN].field->logical_maximum;
 321         pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
 322         pidff->effect_direction->value[0] =
 323                 pidff_rescale(effect->direction, 0xffff,
 324                                 pidff->effect_direction);
 325         pidff->set_effect[PID_START_DELAY].value[0] = effect->replay.delay;
 326
 327         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
 328                           USB_DIR_OUT);
 329 }
 330
 331 /*
 332  * Test if the values used in set_effect have changed
 333  */
 334 static int pidff_needs_set_effect(struct ff_effect *effect,
 335                                   struct ff_effect *old)
 336 {
 337         return effect->replay.length != old->replay.length ||
 338                effect->trigger.interval != old->trigger.interval ||
 339                effect->trigger.button != old->trigger.button ||
 340                effect->direction != old->direction ||
 341                effect->replay.delay != old->replay.delay;
 342 }
 343
 344 /*
 345  * Send periodic effect report to the device
 346  */
 347 static void pidff_set_periodic_report(struct pidff_device *pidff,
 348                                       struct ff_effect *effect)
 349 {
 350         pidff->set_periodic[PID_EFFECT_BLOCK_INDEX].value[0] =
 351                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 352         pidff_set_signed(&pidff->set_periodic[PID_MAGNITUDE],
 353                          effect->u.periodic.magnitude);
 354         pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
 355                          effect->u.periodic.offset);
 356         pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
 357         pidff->set_periodic[PID_PERIOD].value[0] = effect->u.periodic.period;
 358
 359         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_PERIODIC],
 360                           USB_DIR_OUT);
 361
 362 }
 363
 364 /*
 365  * Test if periodic effect parameters have changed
 366  */
 367 static int pidff_needs_set_periodic(struct ff_effect *effect,
 368                                     struct ff_effect *old)
 369 {
 370         return effect->u.periodic.magnitude != old->u.periodic.magnitude ||
 371                effect->u.periodic.offset != old->u.periodic.offset ||
 372                effect->u.periodic.phase != old->u.periodic.phase ||
 373                effect->u.periodic.period != old->u.periodic.period;
 374 }
 375
 376 /*
 377  * Send condition effect reports to the device
 378  */
 379 static void pidff_set_condition_report(struct pidff_device *pidff,
 380                                        struct ff_effect *effect)
 381 {
 382         int i;
 383
 384         pidff->set_condition[PID_EFFECT_BLOCK_INDEX].value[0] =
 385                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 386
 387         for (i = 0; i < 2; i++) {
 388                 pidff->set_condition[PID_PARAM_BLOCK_OFFSET].value[0] = i;
 389                 pidff_set_signed(&pidff->set_condition[PID_CP_OFFSET],
 390                                  effect->u.condition[i].center);
 391                 pidff_set_signed(&pidff->set_condition[PID_POS_COEFFICIENT],
 392                                  effect->u.condition[i].right_coeff);
 393                 pidff_set_signed(&pidff->set_condition[PID_NEG_COEFFICIENT],
 394                                  effect->u.condition[i].left_coeff);
 395                 pidff_set(&pidff->set_condition[PID_POS_SATURATION],
 396                           effect->u.condition[i].right_saturation);
 397                 pidff_set(&pidff->set_condition[PID_NEG_SATURATION],
 398                           effect->u.condition[i].left_saturation);
 399                 pidff_set(&pidff->set_condition[PID_DEAD_BAND],
 400                           effect->u.condition[i].deadband);
 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_submit_report(pidff->hid, pidff->reports[PID_EFFECT_OPERATION],
 516                           USB_DIR_OUT);
 517 }
 518
 519 /**
 520  * Play the effect with effect id @effect_id for @value times
 521  */
 522 static int pidff_playback(struct input_dev *dev, int effect_id, int value)
 523 {
 524         struct pidff_device *pidff = dev->ff->private;
 525
 526         pidff_playback_pid(pidff, pidff->pid_id[effect_id], value);
 527
 528         return 0;
 529 }
 530
 531 /*
 532  * Erase effect with PID id
 533  */
 534 static void pidff_erase_pid(struct pidff_device *pidff, int pid_id)
 535 {
 536         pidff->block_free[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
 537         usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_FREE],
 538                           USB_DIR_OUT);
 539 }
 540
 541 /*
 542  * Stop and erase effect with effect_id
 543  */
 544 static int pidff_erase_effect(struct input_dev *dev, int effect_id)
 545 {
 546         struct pidff_device *pidff = dev->ff->private;
 547         int pid_id = pidff->pid_id[effect_id];
 548
 549         debug("starting to erase %d/%d", effect_id, pidff->pid_id[effect_id]);
 550         /* Wait for the queue to clear. We do not want a full fifo to
 551            prevent the effect removal. */
 552         usbhid_wait_io(pidff->hid);
 553         pidff_playback_pid(pidff, pid_id, 0);
 554         pidff_erase_pid(pidff, pid_id);
 555
 556         return 0;
 557 }
 558
 559 /*
 560  * Effect upload handler
 561  */
 562 static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
 563                                struct ff_effect *old)
 564 {
 565         struct pidff_device *pidff = dev->ff->private;
 566         int type_id;
 567         int error;
 568
 569         switch (effect->type) {
 570         case FF_CONSTANT:
 571                 if (!old) {
 572                         error = pidff_request_effect_upload(pidff,
 573                                         pidff->type_id[PID_CONSTANT]);
 574                         if (error)
 575                                 return error;
 576                 }
 577                 if (!old || pidff_needs_set_effect(effect, old))
 578                         pidff_set_effect_report(pidff, effect);
 579                 if (!old || pidff_needs_set_constant(effect, old))
 580                         pidff_set_constant_force_report(pidff, effect);
 581                 if (!old ||
 582                     pidff_needs_set_envelope(&effect->u.constant.envelope,
 583                                         &old->u.constant.envelope))
 584                         pidff_set_envelope_report(pidff,
 585                                         &effect->u.constant.envelope);
 586                 break;
 587
 588         case FF_PERIODIC:
 589                 if (!old) {
 590                         switch (effect->u.periodic.waveform) {
 591                         case FF_SQUARE:
 592                                 type_id = PID_SQUARE;
 593                                 break;
 594                         case FF_TRIANGLE:
 595                                 type_id = PID_TRIANGLE;
 596                                 break;
 597                         case FF_SINE:
 598                                 type_id = PID_SINE;
 599                                 break;
 600                         case FF_SAW_UP:
 601                                 type_id = PID_SAW_UP;
 602                                 break;
 603                         case FF_SAW_DOWN:
 604                                 type_id = PID_SAW_DOWN;
 605                                 break;
 606                         default:
 607                                 printk(KERN_ERR
 608                                        "hid-pidff: invalid waveform\n");
 609                                 return -EINVAL;
 610                         }
 611
 612                         error = pidff_request_effect_upload(pidff,
 613                                         pidff->type_id[type_id]);
 614                         if (error)
 615                                 return error;
 616                 }
 617                 if (!old || pidff_needs_set_effect(effect, old))
 618                         pidff_set_effect_report(pidff, effect);
 619                 if (!old || pidff_needs_set_periodic(effect, old))
 620                         pidff_set_periodic_report(pidff, effect);
 621                 if (!old ||
 622                     pidff_needs_set_envelope(&effect->u.periodic.envelope,
 623                                         &old->u.periodic.envelope))
 624                         pidff_set_envelope_report(pidff,
 625                                         &effect->u.periodic.envelope);
 626                 break;
 627
 628         case FF_RAMP:
 629                 if (!old) {
 630                         error = pidff_request_effect_upload(pidff,
 631                                         pidff->type_id[PID_RAMP]);
 632                         if (error)
 633                                 return error;
 634                 }
 635                 if (!old || pidff_needs_set_effect(effect, old))
 636                         pidff_set_effect_report(pidff, effect);
 637                 if (!old || pidff_needs_set_ramp(effect, old))
 638                         pidff_set_ramp_force_report(pidff, effect);
 639                 if (!old ||
 640                     pidff_needs_set_envelope(&effect->u.ramp.envelope,
 641                                         &old->u.ramp.envelope))
 642                         pidff_set_envelope_report(pidff,
 643                                         &effect->u.ramp.envelope);
 644                 break;
 645
 646         case FF_SPRING:
 647                 if (!old) {
 648                         error = pidff_request_effect_upload(pidff,
 649                                         pidff->type_id[PID_SPRING]);
 650                         if (error)
 651                                 return error;
 652                 }
 653                 if (!old || pidff_needs_set_effect(effect, old))
 654                         pidff_set_effect_report(pidff, effect);
 655                 if (!old || pidff_needs_set_condition(effect, old))
 656                         pidff_set_condition_report(pidff, effect);
 657                 break;
 658
 659         case FF_FRICTION:
 660                 if (!old) {
 661                         error = pidff_request_effect_upload(pidff,
 662                                         pidff->type_id[PID_FRICTION]);
 663                         if (error)
 664                                 return error;
 665                 }
 666                 if (!old || pidff_needs_set_effect(effect, old))
 667                         pidff_set_effect_report(pidff, effect);
 668                 if (!old || pidff_needs_set_condition(effect, old))
 669                         pidff_set_condition_report(pidff, effect);
 670                 break;
 671
 672         case FF_DAMPER:
 673                 if (!old) {
 674                         error = pidff_request_effect_upload(pidff,
 675                                         pidff->type_id[PID_DAMPER]);
 676                         if (error)
 677                                 return error;
 678                 }
 679                 if (!old || pidff_needs_set_effect(effect, old))
 680                         pidff_set_effect_report(pidff, effect);
 681                 if (!old || pidff_needs_set_condition(effect, old))
 682                         pidff_set_condition_report(pidff, effect);
 683                 break;
 684
 685         case FF_INERTIA:
 686                 if (!old) {
 687                         error = pidff_request_effect_upload(pidff,
 688                                         pidff->type_id[PID_INERTIA]);
 689                         if (error)
 690                                 return error;
 691                 }
 692                 if (!old || pidff_needs_set_effect(effect, old))
 693                         pidff_set_effect_report(pidff, effect);
 694                 if (!old || pidff_needs_set_condition(effect, old))
 695                         pidff_set_condition_report(pidff, effect);
 696                 break;
 697
 698         default:
 699                 printk(KERN_ERR "hid-pidff: invalid type\n");
 700                 return -EINVAL;
 701         }
 702
 703         if (!old)
 704                 pidff->pid_id[effect->id] =
 705                     pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 706
 707         debug("uploaded");
 708
 709         return 0;
 710 }
 711
 712 /*
 713  * set_gain() handler
 714  */
 715 static void pidff_set_gain(struct input_dev *dev, u16 gain)
 716 {
 717         struct pidff_device *pidff = dev->ff->private;
 718
 719         pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
 720         usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
 721                           USB_DIR_OUT);
 722 }
 723
 724 static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
 725 {
 726         struct hid_field *field =
 727                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;
 728
 729         if (!magnitude) {
 730                 pidff_playback_pid(pidff, field->logical_minimum, 0);
 731                 return;
 732         }
 733
 734         pidff_playback_pid(pidff, field->logical_minimum, 1);
 735
 736         pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
 737                 pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
 738         pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
 739         pidff->set_effect[PID_DURATION].value[0] = 0;
 740         pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
 741         pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
 742         pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
 743         pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
 744         pidff->set_effect[PID_START_DELAY].value[0] = 0;
 745
 746         usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
 747                           USB_DIR_OUT);
 748 }
 749
 750 /*
 751  * pidff_set_autocenter() handler
 752  */
 753 static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
 754 {
 755         struct pidff_device *pidff = dev->ff->private;
 756
 757         pidff_autocenter(pidff, magnitude);
 758 }
 759
 760 /*
 761  * Find fields from a report and fill a pidff_usage
 762  */
 763 static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
 764                              struct hid_report *report, int count, int strict)
 765 {
 766         int i, j, k, found;
 767
 768         for (k = 0; k < count; k++) {
 769                 found = 0;
 770                 for (i = 0; i < report->maxfield; i++) {
 771                         if (report->field[i]->maxusage !=
 772                             report->field[i]->report_count) {
 773                                 debug("maxusage and report_count do not match, "
 774                                       "skipping");
 775                                 continue;
 776                         }
 777                         for (j = 0; j < report->field[i]->maxusage; j++) {
 778                                 if (report->field[i]->usage[j].hid ==
 779                                     (HID_UP_PID | table[k])) {
 780                                         debug("found %d at %d->%d", k, i, j);
 781                                         usage[k].field = report->field[i];
 782                                         usage[k].value =
 783                                                 &report->field[i]->value[j];
 784                                         found = 1;
 785                                         break;
 786                                 }
 787                         }
 788                         if (found)
 789                                 break;
 790                 }
 791                 if (!found && strict) {
 792                         debug("failed to locate %d", k);
 793                         return -1;
 794                 }
 795         }
 796         return 0;
 797 }
 798
 799 /*
 800  * Return index into pidff_reports for the given usage
 801  */
 802 static int pidff_check_usage(int usage)
 803 {
 804         int i;
 805
 806         for (i = 0; i < sizeof(pidff_reports); i++)
 807                 if (usage == (HID_UP_PID | pidff_reports[i]))
 808                         return i;
 809
 810         return -1;
 811 }
 812
 813 /*
 814  * Find the reports and fill pidff->reports[]
 815  * report_type specifies either OUTPUT or FEATURE reports
 816  */
 817 static void pidff_find_reports(struct hid_device *hid, int report_type,
 818                                struct pidff_device *pidff)
 819 {
 820         struct hid_report *report;
 821         int i, ret;
 822
 823         list_for_each_entry(report,
 824                             &hid->report_enum[report_type].report_list, list) {
 825                 if (report->maxfield < 1)
 826                         continue;
 827                 ret = pidff_check_usage(report->field[0]->logical);
 828                 if (ret != -1) {
 829                         debug("found usage 0x%02x from field->logical",
 830                               pidff_reports[ret]);
 831                         pidff->reports[ret] = report;
 832                         continue;
 833                 }
 834
 835                 /*
 836                  * Sometimes logical collections are stacked to indicate
 837                  * different usages for the report and the field, in which
 838                  * case we want the usage of the parent. However, Linux HID
 839                  * implementation hides this fact, so we have to dig it up
 840                  * ourselves
 841                  */
 842                 i = report->field[0]->usage[0].collection_index;
 843                 if (i <= 0 ||
 844                     hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
 845                         continue;
 846                 ret = pidff_check_usage(hid->collection[i - 1].usage);
 847                 if (ret != -1 && !pidff->reports[ret]) {
 848                         debug("found usage 0x%02x from collection array",
 849                               pidff_reports[ret]);
 850                         pidff->reports[ret] = report;
 851                 }
 852         }
 853 }
 854
 855 /*
 856  * Test if the required reports have been found
 857  */
 858 static int pidff_reports_ok(struct pidff_device *pidff)
 859 {
 860         int i;
 861
 862         for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
 863                 if (!pidff->reports[i]) {
 864                         debug("%d missing", i);
 865                         return 0;
 866                 }
 867         }
 868
 869         return 1;
 870 }
 871
 872 /*
 873  * Find a field with a specific usage within a report
 874  */
 875 static struct hid_field *pidff_find_special_field(struct hid_report *report,
 876                                                   int usage, int enforce_min)
 877 {
 878         int i;
 879
 880         for (i = 0; i < report->maxfield; i++) {
 881                 if (report->field[i]->logical == (HID_UP_PID | usage) &&
 882                     report->field[i]->report_count > 0) {
 883                         if (!enforce_min ||
 884                             report->field[i]->logical_minimum == 1)
 885                                 return report->field[i];
 886                         else {
 887                                 printk(KERN_ERR "hid-pidff: logical_minimum "
 888                                         "is not 1 as it should be\n");
 889                                 return NULL;
 890                         }
 891                 }
 892         }
 893         return NULL;
 894 }
 895
 896 /*
 897  * Fill a pidff->*_id struct table
 898  */
 899 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
 900                                    const u8 *usagetable, int count)
 901 {
 902
 903         int i, j;
 904         int found = 0;
 905
 906         for (i = 0; i < count; i++) {
 907                 for (j = 0; j < fld->maxusage; j++) {
 908                         if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
 909                                 keys[i] = j + 1;
 910                                 found++;
 911                                 break;
 912                         }
 913                 }
 914         }
 915         return found;
 916 }
 917
 918 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
 919         pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
 920                 sizeof(pidff_ ## name))
 921
 922 /*
 923  * Find and check the special fields
 924  */
 925 static int pidff_find_special_fields(struct pidff_device *pidff)
 926 {
 927         debug("finding special fields");
 928
 929         pidff->create_new_effect_type =
 930                 pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
 931                                          0x25, 1);
 932         pidff->set_effect_type =
 933                 pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 934                                          0x25, 1);
 935         pidff->effect_direction =
 936                 pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 937                                          0x57, 0);
 938         pidff->device_control =
 939                 pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
 940                                          0x96, 1);
 941         pidff->block_load_status =
 942                 pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
 943                                          0x8b, 1);
 944         pidff->effect_operation_status =
 945                 pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
 946                                          0x78, 1);
 947
 948         debug("search done");
 949
 950         if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
 951                 printk(KERN_ERR "hid-pidff: effect lists not found\n");
 952                 return -1;
 953         }
 954
 955         if (!pidff->effect_direction) {
 956                 printk(KERN_ERR "hid-pidff: direction field not found\n");
 957                 return -1;
 958         }
 959
 960         if (!pidff->device_control) {
 961                 printk(KERN_ERR "hid-pidff: device control field not found\n");
 962                 return -1;
 963         }
 964
 965         if (!pidff->block_load_status) {
 966                 printk(KERN_ERR
 967                        "hid-pidff: block load status field not found\n");
 968                 return -1;
 969         }
 970
 971         if (!pidff->effect_operation_status) {
 972                 printk(KERN_ERR
 973                        "hid-pidff: effect operation field not found\n");
 974                 return -1;
 975         }
 976
 977         pidff_find_special_keys(pidff->control_id, pidff->device_control,
 978                                 pidff_device_control,
 979                                 sizeof(pidff_device_control));
 980
 981         PIDFF_FIND_SPECIAL_KEYS(control_id, device_control, device_control);
 982
 983         if (!PIDFF_FIND_SPECIAL_KEYS(type_id, create_new_effect_type,
 984                                      effect_types)) {
 985                 printk(KERN_ERR "hid-pidff: no effect types found\n");
 986                 return -1;
 987         }
 988
 989         if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
 990                                     block_load_status) !=
 991                         sizeof(pidff_block_load_status)) {
 992                 printk(KERN_ERR
 993                        "hidpidff: block load status identifiers not found\n");
 994                 return -1;
 995         }
 996
 997         if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
 998                                     effect_operation_status) !=
 999                         sizeof(pidff_effect_operation_status)) {
1000                 printk(KERN_ERR
1001                        "hidpidff: effect operation identifiers not found\n");
1002                 return -1;
1003         }
1004
1005         return 0;
1006 }
1007
1008 /**
1009  * Find the implemented effect types
1010  */
1011 static int pidff_find_effects(struct pidff_device *pidff,
1012                               struct input_dev *dev)
1013 {
1014         int i;
1015
1016         for (i = 0; i < sizeof(pidff_effect_types); i++) {
1017                 int pidff_type = pidff->type_id[i];
1018                 if (pidff->set_effect_type->usage[pidff_type].hid !=
1019                     pidff->create_new_effect_type->usage[pidff_type].hid) {
1020                         printk(KERN_ERR "hid-pidff: "
1021                                "effect type number %d is invalid\n", i);
1022                         return -1;
1023                 }
1024         }
1025
1026         if (pidff->type_id[PID_CONSTANT])
1027                 set_bit(FF_CONSTANT, dev->ffbit);
1028         if (pidff->type_id[PID_RAMP])
1029                 set_bit(FF_RAMP, dev->ffbit);
1030         if (pidff->type_id[PID_SQUARE]) {
1031                 set_bit(FF_SQUARE, dev->ffbit);
1032                 set_bit(FF_PERIODIC, dev->ffbit);
1033         }
1034         if (pidff->type_id[PID_SINE]) {
1035                 set_bit(FF_SINE, dev->ffbit);
1036                 set_bit(FF_PERIODIC, dev->ffbit);
1037         }
1038         if (pidff->type_id[PID_TRIANGLE]) {
1039                 set_bit(FF_TRIANGLE, dev->ffbit);
1040                 set_bit(FF_PERIODIC, dev->ffbit);
1041         }
1042         if (pidff->type_id[PID_SAW_UP]) {
1043                 set_bit(FF_SAW_UP, dev->ffbit);
1044                 set_bit(FF_PERIODIC, dev->ffbit);
1045         }
1046         if (pidff->type_id[PID_SAW_DOWN]) {
1047                 set_bit(FF_SAW_DOWN, dev->ffbit);
1048                 set_bit(FF_PERIODIC, dev->ffbit);
1049         }
1050         if (pidff->type_id[PID_SPRING])
1051                 set_bit(FF_SPRING, dev->ffbit);
1052         if (pidff->type_id[PID_DAMPER])
1053                 set_bit(FF_DAMPER, dev->ffbit);
1054         if (pidff->type_id[PID_INERTIA])
1055                 set_bit(FF_INERTIA, dev->ffbit);
1056         if (pidff->type_id[PID_FRICTION])
1057                 set_bit(FF_FRICTION, dev->ffbit);
1058
1059         return 0;
1060
1061 }
1062
1063 #define PIDFF_FIND_FIELDS(name, report, strict) \
1064         pidff_find_fields(pidff->name, pidff_ ## name, \
1065                 pidff->reports[report], \
1066                 sizeof(pidff_ ## name), strict)
1067
1068 /*
1069  * Fill and check the pidff_usages
1070  */
1071 static int pidff_init_fields(struct pidff_device *pidff, struct input_dev *dev)
1072 {
1073         int envelope_ok = 0;
1074
1075         if (PIDFF_FIND_FIELDS(set_effect, PID_SET_EFFECT, 1)) {
1076                 printk(KERN_ERR
1077                        "hid-pidff: unknown set_effect report layout\n");
1078                 return -ENODEV;
1079         }
1080
1081         PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
1082         if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
1083                 printk(KERN_ERR
1084                        "hid-pidff: unknown pid_block_load report layout\n");
1085                 return -ENODEV;
1086         }
1087
1088         if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
1089                 printk(KERN_ERR
1090                        "hid-pidff: unknown effect_operation report layout\n");
1091                 return -ENODEV;
1092         }
1093
1094         if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
1095                 printk(KERN_ERR
1096                        "hid-pidff: unknown pid_block_free report layout\n");
1097                 return -ENODEV;
1098         }
1099
1100         if (!PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1))
1101                 envelope_ok = 1;
1102
1103         if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
1104                 return -ENODEV;
1105
1106         if (!envelope_ok) {
1107                 if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
1108                         printk(KERN_WARNING "hid-pidff: "
1109                                "has constant effect but no envelope\n");
1110                 if (test_and_clear_bit(FF_RAMP, dev->ffbit))
1111                         printk(KERN_WARNING "hid-pidff: "
1112                                 "has ramp effect but no envelope\n");
1113
1114                 if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
1115                         printk(KERN_WARNING "hid-pidff: "
1116                                 "has periodic effect but no envelope\n");
1117         }
1118
1119         if (test_bit(FF_CONSTANT, dev->ffbit) &&
1120             PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
1121                 printk(KERN_WARNING
1122                        "hid-pidff: unknown constant effect layout\n");
1123                 clear_bit(FF_CONSTANT, dev->ffbit);
1124         }
1125
1126         if (test_bit(FF_RAMP, dev->ffbit) &&
1127             PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
1128                 printk(KERN_WARNING "hid-pidff: unknown ramp effect layout\n");
1129                 clear_bit(FF_RAMP, dev->ffbit);
1130         }
1131
1132         if ((test_bit(FF_SPRING, dev->ffbit) ||
1133              test_bit(FF_DAMPER, dev->ffbit) ||
1134              test_bit(FF_FRICTION, dev->ffbit) ||
1135              test_bit(FF_INERTIA, dev->ffbit)) &&
1136             PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1)) {
1137                 printk(KERN_WARNING
1138                        "hid-pidff: unknown condition effect layout\n");
1139                 clear_bit(FF_SPRING, dev->ffbit);
1140                 clear_bit(FF_DAMPER, dev->ffbit);
1141                 clear_bit(FF_FRICTION, dev->ffbit);
1142                 clear_bit(FF_INERTIA, dev->ffbit);
1143         }
1144
1145         if (test_bit(FF_PERIODIC, dev->ffbit) &&
1146             PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
1147                 printk(KERN_WARNING
1148                        "hid-pidff: unknown periodic effect layout\n");
1149                 clear_bit(FF_PERIODIC, dev->ffbit);
1150         }
1151
1152         PIDFF_FIND_FIELDS(pool, PID_POOL, 0);
1153
1154         if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
1155                 set_bit(FF_GAIN, dev->ffbit);
1156
1157         return 0;
1158 }
1159
1160 /*
1161  * Reset the device
1162  */
1163 static void pidff_reset(struct pidff_device *pidff)
1164 {
1165         struct hid_device *hid = pidff->hid;
1166         int i = 0;
1167
1168         pidff->device_control->value[0] = pidff->control_id[PID_RESET];
1169         /* We reset twice as sometimes hid_wait_io isn't waiting long enough */
1170         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1171         usbhid_wait_io(hid);
1172         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1173         usbhid_wait_io(hid);
1174
1175         pidff->device_control->value[0] =
1176                 pidff->control_id[PID_ENABLE_ACTUATORS];
1177         usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1178         usbhid_wait_io(hid);
1179
1180         /* pool report is sometimes messed up, refetch it */
1181         usbhid_submit_report(hid, pidff->reports[PID_POOL], USB_DIR_IN);
1182         usbhid_wait_io(hid);
1183
1184         if (pidff->pool[PID_SIMULTANEOUS_MAX].value) {
1185                 while (pidff->pool[PID_SIMULTANEOUS_MAX].value[0] < 2) {
1186                         if (i++ > 20) {
1187                                 printk(KERN_WARNING "hid-pidff: device reports "
1188                                        "%d simultaneous effects\n",
1189                                        pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1190                                 break;
1191                         }
1192                         debug("pid_pool requested again");
1193                         usbhid_submit_report(hid, pidff->reports[PID_POOL],
1194                                           USB_DIR_IN);
1195                         usbhid_wait_io(hid);
1196                 }
1197         }
1198 }
1199
1200 /*
1201  * Test if autocenter modification is using the supported method
1202  */
1203 static int pidff_check_autocenter(struct pidff_device *pidff,
1204                                   struct input_dev *dev)
1205 {
1206         int error;
1207
1208         /*
1209          * Let's find out if autocenter modification is supported
1210          * Specification doesn't specify anything, so we request an
1211          * effect upload and cancel it immediately. If the approved
1212          * effect id was one above the minimum, then we assume the first
1213          * effect id is a built-in spring type effect used for autocenter
1214          */
1215
1216         error = pidff_request_effect_upload(pidff, 1);
1217         if (error) {
1218                 printk(KERN_ERR "hid-pidff: upload request failed\n");
1219                 return error;
1220         }
1221
1222         if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
1223             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
1224                 pidff_autocenter(pidff, 0xffff);
1225                 set_bit(FF_AUTOCENTER, dev->ffbit);
1226         } else {
1227                 printk(KERN_NOTICE "hid-pidff: "
1228                        "device has unknown autocenter control method\n");
1229         }
1230
1231         pidff_erase_pid(pidff,
1232                         pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);
1233
1234         return 0;
1235
1236 }
1237
1238 /*
1239  * Check if the device is PID and initialize it
1240  */
1241 int hid_pidff_init(struct hid_device *hid)
1242 {
1243         struct pidff_device *pidff;
1244         struct hid_input *hidinput = list_entry(hid->inputs.next,
1245                                                 struct hid_input, list);
1246         struct input_dev *dev = hidinput->input;
1247         struct ff_device *ff;
1248         int max_effects;
1249         int error;
1250
1251         debug("starting pid init");
1252
1253         if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
1254                 debug("not a PID device, no output report");
1255                 return -ENODEV;
1256         }
1257
1258         pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
1259         if (!pidff)
1260                 return -ENOMEM;
1261
1262         pidff->hid = hid;
1263
1264         pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
1265         pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);
1266
1267         if (!pidff_reports_ok(pidff)) {
1268                 debug("reports not ok, aborting");
1269                 error = -ENODEV;
1270                 goto fail;
1271         }
1272
1273         error = pidff_init_fields(pidff, dev);
1274         if (error)
1275                 goto fail;
1276
1277         pidff_reset(pidff);
1278
1279         if (test_bit(FF_GAIN, dev->ffbit)) {
1280                 pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], 0xffff);
1281                 usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
1282                                   USB_DIR_OUT);
1283         }
1284
1285         error = pidff_check_autocenter(pidff, dev);
1286         if (error)
1287                 goto fail;
1288
1289         max_effects =
1290             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
1291             pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
1292             1;
1293         debug("max effects is %d", max_effects);
1294
1295         if (max_effects > PID_EFFECTS_MAX)
1296                 max_effects = PID_EFFECTS_MAX;
1297
1298         if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
1299                 debug("max simultaneous effects is %d",
1300                       pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1301
1302         if (pidff->pool[PID_RAM_POOL_SIZE].value)
1303                 debug("device memory size is %d bytes",
1304                       pidff->pool[PID_RAM_POOL_SIZE].value[0]);
1305
1306         if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
1307             pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
1308                 printk(KERN_NOTICE "hid-pidff: "
1309                        "device does not support device managed pool\n");
1310                 goto fail;
1311         }
1312
1313         error = input_ff_create(dev, max_effects);
1314         if (error)
1315                 goto fail;
1316
1317         ff = dev->ff;
1318         ff->private = pidff;
1319         ff->upload = pidff_upload_effect;
1320         ff->erase = pidff_erase_effect;
1321         ff->set_gain = pidff_set_gain;
1322         ff->set_autocenter = pidff_set_autocenter;
1323         ff->playback = pidff_playback;
1324
1325         printk(KERN_INFO "Force feedback for USB HID PID devices by "
1326                "Anssi Hannula <anssi.hannula@gmail.com>\n");
1327
1328         return 0;
1329
1330  fail:
1331         kfree(pidff);
1332         return error;
1333 }