err.no Git - linux-2.6/blob - drivers/media/video/uvc/uvc_ctrl.c

   1 /*
   2  *      uvc_ctrl.c  --  USB Video Class driver - Controls
   3  *
   4  *      Copyright (C) 2005-2008
   5  *          Laurent Pinchart (laurent.pinchart@skynet.be)
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; either version 2 of the License, or
  10  *      (at your option) any later version.
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/version.h>
  16 #include <linux/list.h>
  17 #include <linux/module.h>
  18 #include <linux/uaccess.h>
  19 #include <linux/usb.h>
  20 #include <linux/videodev2.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/wait.h>
  23 #include <asm/atomic.h>
  24
  25 #include "uvcvideo.h"
  26
  27 #define UVC_CTRL_NDATA          2
  28 #define UVC_CTRL_DATA_CURRENT   0
  29 #define UVC_CTRL_DATA_BACKUP    1
  30
  31 /* ------------------------------------------------------------------------
  32  * Control, formats, ...
  33  */
  34
  35 static struct uvc_control_info uvc_ctrls[] = {
  36         {
  37                 .entity         = UVC_GUID_UVC_PROCESSING,
  38                 .selector       = PU_BRIGHTNESS_CONTROL,
  39                 .index          = 0,
  40                 .size           = 2,
  41                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  42                                 | UVC_CONTROL_RESTORE,
  43         },
  44         {
  45                 .entity         = UVC_GUID_UVC_PROCESSING,
  46                 .selector       = PU_CONTRAST_CONTROL,
  47                 .index          = 1,
  48                 .size           = 2,
  49                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  50                                 | UVC_CONTROL_RESTORE,
  51         },
  52         {
  53                 .entity         = UVC_GUID_UVC_PROCESSING,
  54                 .selector       = PU_HUE_CONTROL,
  55                 .index          = 2,
  56                 .size           = 2,
  57                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  58                                 | UVC_CONTROL_RESTORE | UVC_CONTROL_AUTO_UPDATE,
  59         },
  60         {
  61                 .entity         = UVC_GUID_UVC_PROCESSING,
  62                 .selector       = PU_SATURATION_CONTROL,
  63                 .index          = 3,
  64                 .size           = 2,
  65                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  66                                 | UVC_CONTROL_RESTORE,
  67         },
  68         {
  69                 .entity         = UVC_GUID_UVC_PROCESSING,
  70                 .selector       = PU_SHARPNESS_CONTROL,
  71                 .index          = 4,
  72                 .size           = 2,
  73                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  74                                 | UVC_CONTROL_RESTORE,
  75         },
  76         {
  77                 .entity         = UVC_GUID_UVC_PROCESSING,
  78                 .selector       = PU_GAMMA_CONTROL,
  79                 .index          = 5,
  80                 .size           = 2,
  81                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  82                                 | UVC_CONTROL_RESTORE,
  83         },
  84         {
  85                 .entity         = UVC_GUID_UVC_PROCESSING,
  86                 .selector       = PU_BACKLIGHT_COMPENSATION_CONTROL,
  87                 .index          = 8,
  88                 .size           = 2,
  89                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  90                                 | UVC_CONTROL_RESTORE,
  91         },
  92         {
  93                 .entity         = UVC_GUID_UVC_PROCESSING,
  94                 .selector       = PU_GAIN_CONTROL,
  95                 .index          = 9,
  96                 .size           = 2,
  97                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
  98                                 | UVC_CONTROL_RESTORE,
  99         },
 100         {
 101                 .entity         = UVC_GUID_UVC_PROCESSING,
 102                 .selector       = PU_POWER_LINE_FREQUENCY_CONTROL,
 103                 .index          = 10,
 104                 .size           = 1,
 105                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
 106                                 | UVC_CONTROL_RESTORE,
 107         },
 108         {
 109                 .entity         = UVC_GUID_UVC_PROCESSING,
 110                 .selector       = PU_HUE_AUTO_CONTROL,
 111                 .index          = 11,
 112                 .size           = 1,
 113                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 114                                 | UVC_CONTROL_GET_DEF | UVC_CONTROL_RESTORE,
 115         },
 116         {
 117                 .entity         = UVC_GUID_UVC_CAMERA,
 118                 .selector       = CT_AE_MODE_CONTROL,
 119                 .index          = 1,
 120                 .size           = 1,
 121                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 122                                 | UVC_CONTROL_GET_DEF | UVC_CONTROL_GET_RES
 123                                 | UVC_CONTROL_RESTORE,
 124         },
 125         {
 126                 .entity         = UVC_GUID_UVC_CAMERA,
 127                 .selector       = CT_AE_PRIORITY_CONTROL,
 128                 .index          = 2,
 129                 .size           = 1,
 130                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 131                                 | UVC_CONTROL_RESTORE,
 132         },
 133         {
 134                 .entity         = UVC_GUID_UVC_CAMERA,
 135                 .selector       = CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
 136                 .index          = 3,
 137                 .size           = 4,
 138                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
 139                                 | UVC_CONTROL_RESTORE,
 140         },
 141         {
 142                 .entity         = UVC_GUID_UVC_CAMERA,
 143                 .selector       = CT_FOCUS_ABSOLUTE_CONTROL,
 144                 .index          = 5,
 145                 .size           = 2,
 146                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
 147                                 | UVC_CONTROL_RESTORE | UVC_CONTROL_AUTO_UPDATE,
 148         },
 149         {
 150                 .entity         = UVC_GUID_UVC_CAMERA,
 151                 .selector       = CT_FOCUS_AUTO_CONTROL,
 152                 .index          = 17,
 153                 .size           = 1,
 154                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 155                                 | UVC_CONTROL_GET_DEF | UVC_CONTROL_RESTORE,
 156         },
 157         {
 158                 .entity         = UVC_GUID_UVC_PROCESSING,
 159                 .selector       = PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
 160                 .index          = 12,
 161                 .size           = 1,
 162                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 163                                 | UVC_CONTROL_GET_DEF | UVC_CONTROL_RESTORE,
 164         },
 165         {
 166                 .entity         = UVC_GUID_UVC_PROCESSING,
 167                 .selector       = PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
 168                 .index          = 6,
 169                 .size           = 2,
 170                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
 171                                 | UVC_CONTROL_RESTORE | UVC_CONTROL_AUTO_UPDATE,
 172         },
 173         {
 174                 .entity         = UVC_GUID_UVC_PROCESSING,
 175                 .selector       = PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
 176                 .index          = 13,
 177                 .size           = 1,
 178                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
 179                                 | UVC_CONTROL_GET_DEF | UVC_CONTROL_RESTORE,
 180         },
 181         {
 182                 .entity         = UVC_GUID_UVC_PROCESSING,
 183                 .selector       = PU_WHITE_BALANCE_COMPONENT_CONTROL,
 184                 .index          = 7,
 185                 .size           = 4,
 186                 .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
 187                                 | UVC_CONTROL_RESTORE | UVC_CONTROL_AUTO_UPDATE,
 188         },
 189 };
 190
 191 static struct uvc_menu_info power_line_frequency_controls[] = {
 192         { 0, "Disabled" },
 193         { 1, "50 Hz" },
 194         { 2, "60 Hz" },
 195 };
 196
 197 static struct uvc_menu_info exposure_auto_controls[] = {
 198         { 2, "Auto Mode" },
 199         { 1, "Manual Mode" },
 200         { 4, "Shutter Priority Mode" },
 201         { 8, "Aperture Priority Mode" },
 202 };
 203
 204 static struct uvc_control_mapping uvc_ctrl_mappings[] = {
 205         {
 206                 .id             = V4L2_CID_BRIGHTNESS,
 207                 .name           = "Brightness",
 208                 .entity         = UVC_GUID_UVC_PROCESSING,
 209                 .selector       = PU_BRIGHTNESS_CONTROL,
 210                 .size           = 16,
 211                 .offset         = 0,
 212                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 213                 .data_type      = UVC_CTRL_DATA_TYPE_SIGNED,
 214         },
 215         {
 216                 .id             = V4L2_CID_CONTRAST,
 217                 .name           = "Contrast",
 218                 .entity         = UVC_GUID_UVC_PROCESSING,
 219                 .selector       = PU_CONTRAST_CONTROL,
 220                 .size           = 16,
 221                 .offset         = 0,
 222                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 223                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 224         },
 225         {
 226                 .id             = V4L2_CID_HUE,
 227                 .name           = "Hue",
 228                 .entity         = UVC_GUID_UVC_PROCESSING,
 229                 .selector       = PU_HUE_CONTROL,
 230                 .size           = 16,
 231                 .offset         = 0,
 232                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 233                 .data_type      = UVC_CTRL_DATA_TYPE_SIGNED,
 234         },
 235         {
 236                 .id             = V4L2_CID_SATURATION,
 237                 .name           = "Saturation",
 238                 .entity         = UVC_GUID_UVC_PROCESSING,
 239                 .selector       = PU_SATURATION_CONTROL,
 240                 .size           = 16,
 241                 .offset         = 0,
 242                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 243                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 244         },
 245         {
 246                 .id             = V4L2_CID_SHARPNESS,
 247                 .name           = "Sharpness",
 248                 .entity         = UVC_GUID_UVC_PROCESSING,
 249                 .selector       = PU_SHARPNESS_CONTROL,
 250                 .size           = 16,
 251                 .offset         = 0,
 252                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 253                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 254         },
 255         {
 256                 .id             = V4L2_CID_GAMMA,
 257                 .name           = "Gamma",
 258                 .entity         = UVC_GUID_UVC_PROCESSING,
 259                 .selector       = PU_GAMMA_CONTROL,
 260                 .size           = 16,
 261                 .offset         = 0,
 262                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 263                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 264         },
 265         {
 266                 .id             = V4L2_CID_BACKLIGHT_COMPENSATION,
 267                 .name           = "Backlight Compensation",
 268                 .entity         = UVC_GUID_UVC_PROCESSING,
 269                 .selector       = PU_BACKLIGHT_COMPENSATION_CONTROL,
 270                 .size           = 16,
 271                 .offset         = 0,
 272                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 273                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 274         },
 275         {
 276                 .id             = V4L2_CID_GAIN,
 277                 .name           = "Gain",
 278                 .entity         = UVC_GUID_UVC_PROCESSING,
 279                 .selector       = PU_GAIN_CONTROL,
 280                 .size           = 16,
 281                 .offset         = 0,
 282                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 283                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 284         },
 285         {
 286                 .id             = V4L2_CID_POWER_LINE_FREQUENCY,
 287                 .name           = "Power Line Frequency",
 288                 .entity         = UVC_GUID_UVC_PROCESSING,
 289                 .selector       = PU_POWER_LINE_FREQUENCY_CONTROL,
 290                 .size           = 2,
 291                 .offset         = 0,
 292                 .v4l2_type      = V4L2_CTRL_TYPE_MENU,
 293                 .data_type      = UVC_CTRL_DATA_TYPE_ENUM,
 294                 .menu_info      = power_line_frequency_controls,
 295                 .menu_count     = ARRAY_SIZE(power_line_frequency_controls),
 296         },
 297         {
 298                 .id             = V4L2_CID_HUE_AUTO,
 299                 .name           = "Hue, Auto",
 300                 .entity         = UVC_GUID_UVC_PROCESSING,
 301                 .selector       = PU_HUE_AUTO_CONTROL,
 302                 .size           = 1,
 303                 .offset         = 0,
 304                 .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
 305                 .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
 306         },
 307         {
 308                 .id             = V4L2_CID_EXPOSURE_AUTO,
 309                 .name           = "Exposure, Auto",
 310                 .entity         = UVC_GUID_UVC_CAMERA,
 311                 .selector       = CT_AE_MODE_CONTROL,
 312                 .size           = 4,
 313                 .offset         = 0,
 314                 .v4l2_type      = V4L2_CTRL_TYPE_MENU,
 315                 .data_type      = UVC_CTRL_DATA_TYPE_BITMASK,
 316                 .menu_info      = exposure_auto_controls,
 317                 .menu_count     = ARRAY_SIZE(exposure_auto_controls),
 318         },
 319         {
 320                 .id             = V4L2_CID_EXPOSURE_AUTO_PRIORITY,
 321                 .name           = "Exposure, Auto Priority",
 322                 .entity         = UVC_GUID_UVC_CAMERA,
 323                 .selector       = CT_AE_PRIORITY_CONTROL,
 324                 .size           = 1,
 325                 .offset         = 0,
 326                 .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
 327                 .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
 328         },
 329         {
 330                 .id             = V4L2_CID_EXPOSURE_ABSOLUTE,
 331                 .name           = "Exposure (Absolute)",
 332                 .entity         = UVC_GUID_UVC_CAMERA,
 333                 .selector       = CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
 334                 .size           = 32,
 335                 .offset         = 0,
 336                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 337                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 338         },
 339         {
 340                 .id             = V4L2_CID_AUTO_WHITE_BALANCE,
 341                 .name           = "White Balance Temperature, Auto",
 342                 .entity         = UVC_GUID_UVC_PROCESSING,
 343                 .selector       = PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
 344                 .size           = 1,
 345                 .offset         = 0,
 346                 .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
 347                 .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
 348         },
 349         {
 350                 .id             = V4L2_CID_WHITE_BALANCE_TEMPERATURE,
 351                 .name           = "White Balance Temperature",
 352                 .entity         = UVC_GUID_UVC_PROCESSING,
 353                 .selector       = PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
 354                 .size           = 16,
 355                 .offset         = 0,
 356                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 357                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 358         },
 359         {
 360                 .id             = V4L2_CID_AUTO_WHITE_BALANCE,
 361                 .name           = "White Balance Component, Auto",
 362                 .entity         = UVC_GUID_UVC_PROCESSING,
 363                 .selector       = PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
 364                 .size           = 1,
 365                 .offset         = 0,
 366                 .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
 367                 .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
 368         },
 369         {
 370                 .id             = V4L2_CID_BLUE_BALANCE,
 371                 .name           = "White Balance Blue Component",
 372                 .entity         = UVC_GUID_UVC_PROCESSING,
 373                 .selector       = PU_WHITE_BALANCE_COMPONENT_CONTROL,
 374                 .size           = 16,
 375                 .offset         = 0,
 376                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 377                 .data_type      = UVC_CTRL_DATA_TYPE_SIGNED,
 378         },
 379         {
 380                 .id             = V4L2_CID_RED_BALANCE,
 381                 .name           = "White Balance Red Component",
 382                 .entity         = UVC_GUID_UVC_PROCESSING,
 383                 .selector       = PU_WHITE_BALANCE_COMPONENT_CONTROL,
 384                 .size           = 16,
 385                 .offset         = 16,
 386                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 387                 .data_type      = UVC_CTRL_DATA_TYPE_SIGNED,
 388         },
 389         {
 390                 .id             = V4L2_CID_FOCUS_ABSOLUTE,
 391                 .name           = "Focus (absolute)",
 392                 .entity         = UVC_GUID_UVC_CAMERA,
 393                 .selector       = CT_FOCUS_ABSOLUTE_CONTROL,
 394                 .size           = 16,
 395                 .offset         = 0,
 396                 .v4l2_type      = V4L2_CTRL_TYPE_INTEGER,
 397                 .data_type      = UVC_CTRL_DATA_TYPE_UNSIGNED,
 398         },
 399         {
 400                 .id             = V4L2_CID_FOCUS_AUTO,
 401                 .name           = "Focus, Auto",
 402                 .entity         = UVC_GUID_UVC_CAMERA,
 403                 .selector       = CT_FOCUS_AUTO_CONTROL,
 404                 .size           = 1,
 405                 .offset         = 0,
 406                 .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
 407                 .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
 408         },
 409 };
 410
 411 /* ------------------------------------------------------------------------
 412  * Utility functions
 413  */
 414
 415 static inline __u8 *uvc_ctrl_data(struct uvc_control *ctrl, int id)
 416 {
 417         return ctrl->data + id * ctrl->info->size;
 418 }
 419
 420 static inline int uvc_get_bit(const __u8 *data, int bit)
 421 {
 422         return (data[bit >> 3] >> (bit & 7)) & 1;
 423 }
 424
 425 /* Extract the bit string specified by mapping->offset and mapping->size
 426  * from the little-endian data stored at 'data' and return the result as
 427  * a signed 32bit integer. Sign extension will be performed if the mapping
 428  * references a signed data type.
 429  */
 430 static __s32 uvc_get_le_value(const __u8 *data,
 431         struct uvc_control_mapping *mapping)
 432 {
 433         int bits = mapping->size;
 434         int offset = mapping->offset;
 435         __s32 value = 0;
 436         __u8 mask;
 437
 438         data += offset / 8;
 439         offset &= 7;
 440         mask = ((1LL << bits) - 1) << offset;
 441
 442         for (; bits > 0; data++) {
 443                 __u8 byte = *data & mask;
 444                 value |= offset > 0 ? (byte >> offset) : (byte << (-offset));
 445                 bits -= 8 - (offset > 0 ? offset : 0);
 446                 offset -= 8;
 447                 mask = (1 << bits) - 1;
 448         }
 449
 450         /* Sign-extend the value if needed */
 451         if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
 452                 value |= -(value & (1 << (mapping->size - 1)));
 453
 454         return value;
 455 }
 456
 457 /* Set the bit string specified by mapping->offset and mapping->size
 458  * in the little-endian data stored at 'data' to the value 'value'.
 459  */
 460 static void uvc_set_le_value(__s32 value, __u8 *data,
 461         struct uvc_control_mapping *mapping)
 462 {
 463         int bits = mapping->size;
 464         int offset = mapping->offset;
 465         __u8 mask;
 466
 467         data += offset / 8;
 468         offset &= 7;
 469
 470         for (; bits > 0; data++) {
 471                 mask = ((1LL << bits) - 1) << offset;
 472                 *data = (*data & ~mask) | ((value << offset) & mask);
 473                 value >>= offset ? offset : 8;
 474                 bits -= 8 - offset;
 475                 offset = 0;
 476         }
 477 }
 478
 479 /* ------------------------------------------------------------------------
 480  * Terminal and unit management
 481  */
 482
 483 static const __u8 uvc_processing_guid[16] = UVC_GUID_UVC_PROCESSING;
 484 static const __u8 uvc_camera_guid[16] = UVC_GUID_UVC_CAMERA;
 485 static const __u8 uvc_media_transport_input_guid[16] =
 486         UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT;
 487
 488 static int uvc_entity_match_guid(struct uvc_entity *entity, __u8 guid[16])
 489 {
 490         switch (UVC_ENTITY_TYPE(entity)) {
 491         case ITT_CAMERA:
 492                 return memcmp(uvc_camera_guid, guid, 16) == 0;
 493
 494         case ITT_MEDIA_TRANSPORT_INPUT:
 495                 return memcmp(uvc_media_transport_input_guid, guid, 16) == 0;
 496
 497         case VC_PROCESSING_UNIT:
 498                 return memcmp(uvc_processing_guid, guid, 16) == 0;
 499
 500         case VC_EXTENSION_UNIT:
 501                 return memcmp(entity->extension.guidExtensionCode,
 502                               guid, 16) == 0;
 503
 504         default:
 505                 return 0;
 506         }
 507 }
 508
 509 /* ------------------------------------------------------------------------
 510  * UVC Controls
 511  */
 512
 513 static void __uvc_find_control(struct uvc_entity *entity, __u32 v4l2_id,
 514         struct uvc_control_mapping **mapping, struct uvc_control **control,
 515         int next)
 516 {
 517         struct uvc_control *ctrl;
 518         struct uvc_control_mapping *map;
 519         unsigned int i;
 520
 521         if (entity == NULL)
 522                 return;
 523
 524         for (i = 0; i < entity->ncontrols; ++i) {
 525                 ctrl = &entity->controls[i];
 526                 if (ctrl->info == NULL)
 527                         continue;
 528
 529                 list_for_each_entry(map, &ctrl->info->mappings, list) {
 530                         if ((map->id == v4l2_id) && !next) {
 531                                 *control = ctrl;
 532                                 *mapping = map;
 533                                 return;
 534                         }
 535
 536                         if ((*mapping == NULL || (*mapping)->id > map->id) &&
 537                             (map->id > v4l2_id) && next) {
 538                                 *control = ctrl;
 539                                 *mapping = map;
 540                         }
 541                 }
 542         }
 543 }
 544
 545 struct uvc_control *uvc_find_control(struct uvc_video_device *video,
 546         __u32 v4l2_id, struct uvc_control_mapping **mapping)
 547 {
 548         struct uvc_control *ctrl = NULL;
 549         struct uvc_entity *entity;
 550         int next = v4l2_id & V4L2_CTRL_FLAG_NEXT_CTRL;
 551
 552         *mapping = NULL;
 553
 554         /* Mask the query flags. */
 555         v4l2_id &= V4L2_CTRL_ID_MASK;
 556
 557         /* Find the control. */
 558         __uvc_find_control(video->processing, v4l2_id, mapping, &ctrl, next);
 559         if (ctrl && !next)
 560                 return ctrl;
 561
 562         list_for_each_entry(entity, &video->iterms, chain) {
 563                 __uvc_find_control(entity, v4l2_id, mapping, &ctrl, next);
 564                 if (ctrl && !next)
 565                         return ctrl;
 566         }
 567
 568         list_for_each_entry(entity, &video->extensions, chain) {
 569                 __uvc_find_control(entity, v4l2_id, mapping, &ctrl, next);
 570                 if (ctrl && !next)
 571                         return ctrl;
 572         }
 573
 574         if (ctrl == NULL && !next)
 575                 uvc_trace(UVC_TRACE_CONTROL, "Control 0x%08x not found.\n",
 576                                 v4l2_id);
 577
 578         return ctrl;
 579 }
 580
 581 int uvc_query_v4l2_ctrl(struct uvc_video_device *video,
 582         struct v4l2_queryctrl *v4l2_ctrl)
 583 {
 584         struct uvc_control *ctrl;
 585         struct uvc_control_mapping *mapping;
 586         struct uvc_menu_info *menu;
 587         unsigned int i;
 588         __u8 data[8];
 589         int ret;
 590
 591         ctrl = uvc_find_control(video, v4l2_ctrl->id, &mapping);
 592         if (ctrl == NULL)
 593                 return -EINVAL;
 594
 595         memset(v4l2_ctrl, 0, sizeof *v4l2_ctrl);
 596         v4l2_ctrl->id = mapping->id;
 597         v4l2_ctrl->type = mapping->v4l2_type;
 598         strncpy(v4l2_ctrl->name, mapping->name, sizeof v4l2_ctrl->name);
 599         v4l2_ctrl->flags = 0;
 600
 601         if (!(ctrl->info->flags & UVC_CONTROL_SET_CUR))
 602                 v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
 603
 604         if (ctrl->info->flags & UVC_CONTROL_GET_DEF) {
 605                 if ((ret = uvc_query_ctrl(video->dev, GET_DEF, ctrl->entity->id,
 606                                 video->dev->intfnum, ctrl->info->selector,
 607                                 &data, ctrl->info->size)) < 0)
 608                         return ret;
 609                 v4l2_ctrl->default_value = uvc_get_le_value(data, mapping);
 610         }
 611
 612         switch (mapping->v4l2_type) {
 613         case V4L2_CTRL_TYPE_MENU:
 614                 v4l2_ctrl->minimum = 0;
 615                 v4l2_ctrl->maximum = mapping->menu_count - 1;
 616                 v4l2_ctrl->step = 1;
 617
 618                 menu = mapping->menu_info;
 619                 for (i = 0; i < mapping->menu_count; ++i, ++menu) {
 620                         if (menu->value == v4l2_ctrl->default_value) {
 621                                 v4l2_ctrl->default_value = i;
 622                                 break;
 623                         }
 624                 }
 625
 626                 return 0;
 627
 628         case V4L2_CTRL_TYPE_BOOLEAN:
 629                 v4l2_ctrl->minimum = 0;
 630                 v4l2_ctrl->maximum = 1;
 631                 v4l2_ctrl->step = 1;
 632                 return 0;
 633
 634         default:
 635                 break;
 636         }
 637
 638         if (ctrl->info->flags & UVC_CONTROL_GET_MIN) {
 639                 if ((ret = uvc_query_ctrl(video->dev, GET_MIN, ctrl->entity->id,
 640                                 video->dev->intfnum, ctrl->info->selector,
 641                                 &data, ctrl->info->size)) < 0)
 642                         return ret;
 643                 v4l2_ctrl->minimum = uvc_get_le_value(data, mapping);
 644         }
 645         if (ctrl->info->flags & UVC_CONTROL_GET_MAX) {
 646                 if ((ret = uvc_query_ctrl(video->dev, GET_MAX, ctrl->entity->id,
 647                                 video->dev->intfnum, ctrl->info->selector,
 648                                 &data, ctrl->info->size)) < 0)
 649                         return ret;
 650                 v4l2_ctrl->maximum = uvc_get_le_value(data, mapping);
 651         }
 652         if (ctrl->info->flags & UVC_CONTROL_GET_RES) {
 653                 if ((ret = uvc_query_ctrl(video->dev, GET_RES, ctrl->entity->id,
 654                                 video->dev->intfnum, ctrl->info->selector,
 655                                 &data, ctrl->info->size)) < 0)
 656                         return ret;
 657                 v4l2_ctrl->step = uvc_get_le_value(data, mapping);
 658         }
 659
 660         return 0;
 661 }
 662
 663
 664 /* --------------------------------------------------------------------------
 665  * Control transactions
 666  *
 667  * To make extended set operations as atomic as the hardware allows, controls
 668  * are handled using begin/commit/rollback operations.
 669  *
 670  * At the beginning of a set request, uvc_ctrl_begin should be called to
 671  * initialize the request. This function acquires the control lock.
 672  *
 673  * When setting a control, the new value is stored in the control data field
 674  * at position UVC_CTRL_DATA_CURRENT. The control is then marked as dirty for
 675  * later processing. If the UVC and V4L2 control sizes differ, the current
 676  * value is loaded from the hardware before storing the new value in the data
 677  * field.
 678  *
 679  * After processing all controls in the transaction, uvc_ctrl_commit or
 680  * uvc_ctrl_rollback must be called to apply the pending changes to the
 681  * hardware or revert them. When applying changes, all controls marked as
 682  * dirty will be modified in the UVC device, and the dirty flag will be
 683  * cleared. When reverting controls, the control data field
 684  * UVC_CTRL_DATA_CURRENT is reverted to its previous value
 685  * (UVC_CTRL_DATA_BACKUP) for all dirty controls. Both functions release the
 686  * control lock.
 687  */
 688 int uvc_ctrl_begin(struct uvc_video_device *video)
 689 {
 690         return mutex_lock_interruptible(&video->ctrl_mutex) ? -ERESTARTSYS : 0;
 691 }
 692
 693 static int uvc_ctrl_commit_entity(struct uvc_device *dev,
 694         struct uvc_entity *entity, int rollback)
 695 {
 696         struct uvc_control *ctrl;
 697         unsigned int i;
 698         int ret;
 699
 700         if (entity == NULL)
 701                 return 0;
 702
 703         for (i = 0; i < entity->ncontrols; ++i) {
 704                 ctrl = &entity->controls[i];
 705                 if (ctrl->info == NULL || !ctrl->dirty)
 706                         continue;
 707
 708                 if (!rollback)
 709                         ret = uvc_query_ctrl(dev, SET_CUR, ctrl->entity->id,
 710                                 dev->intfnum, ctrl->info->selector,
 711                                 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 712                                 ctrl->info->size);
 713                 else
 714                         ret = 0;
 715
 716                 if (rollback || ret < 0)
 717                         memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 718                                uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
 719                                ctrl->info->size);
 720
 721                 if ((ctrl->info->flags & UVC_CONTROL_GET_CUR) == 0)
 722                         ctrl->loaded = 0;
 723
 724                 ctrl->dirty = 0;
 725
 726                 if (ret < 0)
 727                         return ret;
 728         }
 729
 730         return 0;
 731 }
 732
 733 int __uvc_ctrl_commit(struct uvc_video_device *video, int rollback)
 734 {
 735         struct uvc_entity *entity;
 736         int ret = 0;
 737
 738         /* Find the control. */
 739         ret = uvc_ctrl_commit_entity(video->dev, video->processing, rollback);
 740         if (ret < 0)
 741                 goto done;
 742
 743         list_for_each_entry(entity, &video->iterms, chain) {
 744                 ret = uvc_ctrl_commit_entity(video->dev, entity, rollback);
 745                 if (ret < 0)
 746                         goto done;
 747         }
 748
 749         list_for_each_entry(entity, &video->extensions, chain) {
 750                 ret = uvc_ctrl_commit_entity(video->dev, entity, rollback);
 751                 if (ret < 0)
 752                         goto done;
 753         }
 754
 755 done:
 756         mutex_unlock(&video->ctrl_mutex);
 757         return ret;
 758 }
 759
 760 int uvc_ctrl_get(struct uvc_video_device *video,
 761         struct v4l2_ext_control *xctrl)
 762 {
 763         struct uvc_control *ctrl;
 764         struct uvc_control_mapping *mapping;
 765         struct uvc_menu_info *menu;
 766         unsigned int i;
 767         int ret;
 768
 769         ctrl = uvc_find_control(video, xctrl->id, &mapping);
 770         if (ctrl == NULL || (ctrl->info->flags & UVC_CONTROL_GET_CUR) == 0)
 771                 return -EINVAL;
 772
 773         if (!ctrl->loaded) {
 774                 ret = uvc_query_ctrl(video->dev, GET_CUR, ctrl->entity->id,
 775                                 video->dev->intfnum, ctrl->info->selector,
 776                                 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 777                                 ctrl->info->size);
 778                 if (ret < 0)
 779                         return ret;
 780
 781                 if ((ctrl->info->flags & UVC_CONTROL_AUTO_UPDATE) == 0)
 782                         ctrl->loaded = 1;
 783         }
 784
 785         xctrl->value = uvc_get_le_value(
 786                 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), mapping);
 787
 788         if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
 789                 menu = mapping->menu_info;
 790                 for (i = 0; i < mapping->menu_count; ++i, ++menu) {
 791                         if (menu->value == xctrl->value) {
 792                                 xctrl->value = i;
 793                                 break;
 794                         }
 795                 }
 796         }
 797
 798         return 0;
 799 }
 800
 801 int uvc_ctrl_set(struct uvc_video_device *video,
 802         struct v4l2_ext_control *xctrl)
 803 {
 804         struct uvc_control *ctrl;
 805         struct uvc_control_mapping *mapping;
 806         s32 value = xctrl->value;
 807         int ret;
 808
 809         ctrl = uvc_find_control(video, xctrl->id, &mapping);
 810         if (ctrl == NULL || (ctrl->info->flags & UVC_CONTROL_SET_CUR) == 0)
 811                 return -EINVAL;
 812
 813         if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
 814                 if (value < 0 || value >= mapping->menu_count)
 815                         return -EINVAL;
 816                 value = mapping->menu_info[value].value;
 817         }
 818
 819         if (!ctrl->loaded && (ctrl->info->size * 8) != mapping->size) {
 820                 if ((ctrl->info->flags & UVC_CONTROL_GET_CUR) == 0) {
 821                         memset(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 822                                 0, ctrl->info->size);
 823                 } else {
 824                         ret = uvc_query_ctrl(video->dev, GET_CUR,
 825                                 ctrl->entity->id, video->dev->intfnum,
 826                                 ctrl->info->selector,
 827                                 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 828                                 ctrl->info->size);
 829                         if (ret < 0)
 830                                 return ret;
 831                 }
 832
 833                 if ((ctrl->info->flags & UVC_CONTROL_AUTO_UPDATE) == 0)
 834                         ctrl->loaded = 1;
 835         }
 836
 837         if (!ctrl->dirty) {
 838                 memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
 839                        uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 840                        ctrl->info->size);
 841         }
 842
 843         uvc_set_le_value(value,
 844                 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), mapping);
 845
 846         ctrl->dirty = 1;
 847         ctrl->modified = 1;
 848         return 0;
 849 }
 850
 851 /* --------------------------------------------------------------------------
 852  * Dynamic controls
 853  */
 854
 855 int uvc_xu_ctrl_query(struct uvc_video_device *video,
 856         struct uvc_xu_control *xctrl, int set)
 857 {
 858         struct uvc_entity *entity;
 859         struct uvc_control *ctrl = NULL;
 860         unsigned int i, found = 0;
 861         __u8 *data;
 862         int ret;
 863
 864         /* Find the extension unit. */
 865         list_for_each_entry(entity, &video->extensions, chain) {
 866                 if (entity->id == xctrl->unit)
 867                         break;
 868         }
 869
 870         if (entity->id != xctrl->unit) {
 871                 uvc_trace(UVC_TRACE_CONTROL, "Extension unit %u not found.\n",
 872                         xctrl->unit);
 873                 return -EINVAL;
 874         }
 875
 876         /* Find the control. */
 877         for (i = 0; i < entity->ncontrols; ++i) {
 878                 ctrl = &entity->controls[i];
 879                 if (ctrl->info == NULL)
 880                         continue;
 881
 882                 if (ctrl->info->selector == xctrl->selector) {
 883                         found = 1;
 884                         break;
 885                 }
 886         }
 887
 888         if (!found) {
 889                 uvc_trace(UVC_TRACE_CONTROL,
 890                         "Control " UVC_GUID_FORMAT "/%u not found.\n",
 891                         UVC_GUID_ARGS(entity->extension.guidExtensionCode),
 892                         xctrl->selector);
 893                 return -EINVAL;
 894         }
 895
 896         /* Validate control data size. */
 897         if (ctrl->info->size != xctrl->size)
 898                 return -EINVAL;
 899
 900         if ((set && !(ctrl->info->flags & UVC_CONTROL_SET_CUR)) ||
 901             (!set && !(ctrl->info->flags & UVC_CONTROL_GET_CUR)))
 902                 return -EINVAL;
 903
 904         if (mutex_lock_interruptible(&video->ctrl_mutex))
 905                 return -ERESTARTSYS;
 906
 907         memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
 908                uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 909                xctrl->size);
 910         data = uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT);
 911
 912         if (set && copy_from_user(data, xctrl->data, xctrl->size)) {
 913                 ret = -EFAULT;
 914                 goto out;
 915         }
 916
 917         ret = uvc_query_ctrl(video->dev, set ? SET_CUR : GET_CUR, xctrl->unit,
 918                              video->dev->intfnum, xctrl->selector, data,
 919                              xctrl->size);
 920         if (ret < 0)
 921                 goto out;
 922
 923         if (!set && copy_to_user(xctrl->data, data, xctrl->size)) {
 924                 ret = -EFAULT;
 925                 goto out;
 926         }
 927
 928 out:
 929         if (ret)
 930                 memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
 931                        uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
 932                        xctrl->size);
 933
 934         mutex_unlock(&video->ctrl_mutex);
 935         return ret;
 936 }
 937
 938 /* --------------------------------------------------------------------------
 939  * Suspend/resume
 940  */
 941
 942 /*
 943  * Restore control values after resume, skipping controls that haven't been
 944  * changed.
 945  *
 946  * TODO
 947  * - Don't restore modified controls that are back to their default value.
 948  * - Handle restore order (Auto-Exposure Mode should be restored before
 949  *   Exposure Time).
 950  */
 951 int uvc_ctrl_resume_device(struct uvc_device *dev)
 952 {
 953         struct uvc_control *ctrl;
 954         struct uvc_entity *entity;
 955         unsigned int i;
 956         int ret;
 957
 958         /* Walk the entities list and restore controls when possible. */
 959         list_for_each_entry(entity, &dev->entities, list) {
 960
 961                 for (i = 0; i < entity->ncontrols; ++i) {
 962                         ctrl = &entity->controls[i];
 963
 964                         if (ctrl->info == NULL || !ctrl->modified ||
 965                             (ctrl->info->flags & UVC_CONTROL_RESTORE) == 0)
 966                                 continue;
 967
 968                         printk(KERN_INFO "restoring control " UVC_GUID_FORMAT
 969                                 "/%u/%u\n", UVC_GUID_ARGS(ctrl->info->entity),
 970                                 ctrl->info->index, ctrl->info->selector);
 971                         ctrl->dirty = 1;
 972                 }
 973
 974                 ret = uvc_ctrl_commit_entity(dev, entity, 0);
 975                 if (ret < 0)
 976                         return ret;
 977         }
 978
 979         return 0;
 980 }
 981
 982 /* --------------------------------------------------------------------------
 983  * Control and mapping handling
 984  */
 985
 986 static void uvc_ctrl_add_ctrl(struct uvc_device *dev,
 987         struct uvc_control_info *info)
 988 {
 989         struct uvc_entity *entity;
 990         struct uvc_control *ctrl = NULL;
 991         int ret, found = 0;
 992         unsigned int i;
 993
 994         list_for_each_entry(entity, &dev->entities, list) {
 995                 if (!uvc_entity_match_guid(entity, info->entity))
 996                         continue;
 997
 998                 for (i = 0; i < entity->ncontrols; ++i) {
 999                         ctrl = &entity->controls[i];
1000                         if (ctrl->index == info->index) {
1001                                 found = 1;
1002                                 break;
1003                         }
1004                 }
1005
1006                 if (found)
1007                         break;
1008         }
1009
1010         if (!found)
1011                 return;
1012
1013         if (UVC_ENTITY_TYPE(entity) == VC_EXTENSION_UNIT) {
1014                 /* Check if the device control information and length match
1015                  * the user supplied information.
1016                  */
1017                 __u32 flags;
1018                 __le16 size;
1019                 __u8 inf;
1020
1021                 if ((ret = uvc_query_ctrl(dev, GET_LEN, ctrl->entity->id,
1022                         dev->intfnum, info->selector, (__u8 *)&size, 2)) < 0) {
1023                         uvc_trace(UVC_TRACE_CONTROL, "GET_LEN failed on "
1024                                 "control " UVC_GUID_FORMAT "/%u (%d).\n",
1025                                 UVC_GUID_ARGS(info->entity), info->selector,
1026                                 ret);
1027                         return;
1028                 }
1029
1030                 if (info->size != le16_to_cpu(size)) {
1031                         uvc_trace(UVC_TRACE_CONTROL, "Control " UVC_GUID_FORMAT
1032                                 "/%u size doesn't match user supplied "
1033                                 "value.\n", UVC_GUID_ARGS(info->entity),
1034                                 info->selector);
1035                         return;
1036                 }
1037
1038                 if ((ret = uvc_query_ctrl(dev, GET_INFO, ctrl->entity->id,
1039                         dev->intfnum, info->selector, &inf, 1)) < 0) {
1040                         uvc_trace(UVC_TRACE_CONTROL, "GET_INFO failed on "
1041                                 "control " UVC_GUID_FORMAT "/%u (%d).\n",
1042                                 UVC_GUID_ARGS(info->entity), info->selector,
1043                                 ret);
1044                         return;
1045                 }
1046
1047                 flags = info->flags;
1048                 if (((flags & UVC_CONTROL_GET_CUR) && !(inf & (1 << 0))) ||
1049                     ((flags & UVC_CONTROL_SET_CUR) && !(inf & (1 << 1)))) {
1050                         uvc_trace(UVC_TRACE_CONTROL, "Control "
1051                                 UVC_GUID_FORMAT "/%u flags don't match "
1052                                 "supported operations.\n",
1053                                 UVC_GUID_ARGS(info->entity), info->selector);
1054                         return;
1055                 }
1056         }
1057
1058         ctrl->info = info;
1059         ctrl->data = kmalloc(ctrl->info->size * UVC_CTRL_NDATA, GFP_KERNEL);
1060         uvc_trace(UVC_TRACE_CONTROL, "Added control " UVC_GUID_FORMAT "/%u "
1061                 "to device %s entity %u\n", UVC_GUID_ARGS(ctrl->info->entity),
1062                 ctrl->info->selector, dev->udev->devpath, entity->id);
1063 }
1064
1065 /*
1066  * Add an item to the UVC control information list, and instantiate a control
1067  * structure for each device that supports the control.
1068  */
1069 int uvc_ctrl_add_info(struct uvc_control_info *info)
1070 {
1071         struct uvc_control_info *ctrl;
1072         struct uvc_device *dev;
1073         int ret = 0;
1074
1075         /* Find matching controls by walking the devices, entities and
1076          * controls list.
1077          */
1078         mutex_lock(&uvc_driver.ctrl_mutex);
1079
1080         /* First check if the list contains a control matching the new one.
1081          * Bail out if it does.
1082          */
1083         list_for_each_entry(ctrl, &uvc_driver.controls, list) {
1084                 if (memcmp(ctrl->entity, info->entity, 16))
1085                         continue;
1086
1087                 if (ctrl->selector == info->selector) {
1088                         uvc_trace(UVC_TRACE_CONTROL, "Control "
1089                                 UVC_GUID_FORMAT "/%u is already defined.\n",
1090                                 UVC_GUID_ARGS(info->entity), info->selector);
1091                         ret = -EEXIST;
1092                         goto end;
1093                 }
1094                 if (ctrl->index == info->index) {
1095                         uvc_trace(UVC_TRACE_CONTROL, "Control "
1096                                 UVC_GUID_FORMAT "/%u would overwrite index "
1097                                 "%d.\n", UVC_GUID_ARGS(info->entity),
1098                                 info->selector, info->index);
1099                         ret = -EEXIST;
1100                         goto end;
1101                 }
1102         }
1103
1104         list_for_each_entry(dev, &uvc_driver.devices, list)
1105                 uvc_ctrl_add_ctrl(dev, info);
1106
1107         INIT_LIST_HEAD(&info->mappings);
1108         list_add_tail(&info->list, &uvc_driver.controls);
1109 end:
1110         mutex_unlock(&uvc_driver.ctrl_mutex);
1111         return ret;
1112 }
1113
1114 int uvc_ctrl_add_mapping(struct uvc_control_mapping *mapping)
1115 {
1116         struct uvc_control_info *info;
1117         struct uvc_control_mapping *map;
1118         int ret = -EINVAL;
1119
1120         if (mapping->id & ~V4L2_CTRL_ID_MASK) {
1121                 uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s' with "
1122                         "invalid control id 0x%08x\n", mapping->name,
1123                         mapping->id);
1124                 return -EINVAL;
1125         }
1126
1127         mutex_lock(&uvc_driver.ctrl_mutex);
1128         list_for_each_entry(info, &uvc_driver.controls, list) {
1129                 if (memcmp(info->entity, mapping->entity, 16) ||
1130                         info->selector != mapping->selector)
1131                         continue;
1132
1133                 if (info->size * 8 < mapping->size + mapping->offset) {
1134                         uvc_trace(UVC_TRACE_CONTROL, "Mapping '%s' would "
1135                                 "overflow control " UVC_GUID_FORMAT "/%u\n",
1136                                 mapping->name, UVC_GUID_ARGS(info->entity),
1137                                 info->selector);
1138                         ret = -EOVERFLOW;
1139                         goto end;
1140                 }
1141
1142                 /* Check if the list contains a mapping matching the new one.
1143                  * Bail out if it does.
1144                  */
1145                 list_for_each_entry(map, &info->mappings, list) {
1146                         if (map->id == mapping->id) {
1147                                 uvc_trace(UVC_TRACE_CONTROL, "Mapping '%s' is "
1148                                         "already defined.\n", mapping->name);
1149                                 ret = -EEXIST;
1150                                 goto end;
1151                         }
1152                 }
1153
1154                 mapping->ctrl = info;
1155                 list_add_tail(&mapping->list, &info->mappings);
1156                 uvc_trace(UVC_TRACE_CONTROL, "Adding mapping %s to control "
1157                         UVC_GUID_FORMAT "/%u.\n", mapping->name,
1158                         UVC_GUID_ARGS(info->entity), info->selector);
1159
1160                 ret = 0;
1161                 break;
1162         }
1163 end:
1164         mutex_unlock(&uvc_driver.ctrl_mutex);
1165         return ret;
1166 }
1167
1168 /*
1169  * Initialize device controls.
1170  */
1171 int uvc_ctrl_init_device(struct uvc_device *dev)
1172 {
1173         struct uvc_control_info *info;
1174         struct uvc_control *ctrl;
1175         struct uvc_entity *entity;
1176         unsigned int i;
1177
1178         /* Walk the entities list and instantiate controls */
1179         list_for_each_entry(entity, &dev->entities, list) {
1180                 unsigned int bControlSize = 0, ncontrols = 0;
1181                 __u8 *bmControls = NULL;
1182
1183                 if (UVC_ENTITY_TYPE(entity) == VC_EXTENSION_UNIT) {
1184                         bmControls = entity->extension.bmControls;
1185                         bControlSize = entity->extension.bControlSize;
1186                 } else if (UVC_ENTITY_TYPE(entity) == VC_PROCESSING_UNIT) {
1187                         bmControls = entity->processing.bmControls;
1188                         bControlSize = entity->processing.bControlSize;
1189                 } else if (UVC_ENTITY_TYPE(entity) == ITT_CAMERA) {
1190                         bmControls = entity->camera.bmControls;
1191                         bControlSize = entity->camera.bControlSize;
1192                 }
1193
1194                 for (i = 0; i < bControlSize; ++i)
1195                         ncontrols += hweight8(bmControls[i]);
1196
1197                 if (ncontrols == 0)
1198                         continue;
1199
1200                 entity->controls = kzalloc(ncontrols*sizeof *ctrl, GFP_KERNEL);
1201                 if (entity->controls == NULL)
1202                         return -ENOMEM;
1203
1204                 entity->ncontrols = ncontrols;
1205
1206                 ctrl = entity->controls;
1207                 for (i = 0; i < bControlSize * 8; ++i) {
1208                         if (uvc_get_bit(bmControls, i) == 0)
1209                                 continue;
1210
1211                         ctrl->entity = entity;
1212                         ctrl->index = i;
1213                         ctrl++;
1214                 }
1215         }
1216
1217         /* Walk the controls info list and associate them with the device
1218          * controls, then add the device to the global device list. This has
1219          * to be done while holding the controls lock, to make sure
1220          * uvc_ctrl_add_info() will not get called in-between.
1221          */
1222         mutex_lock(&uvc_driver.ctrl_mutex);
1223         list_for_each_entry(info, &uvc_driver.controls, list)
1224                 uvc_ctrl_add_ctrl(dev, info);
1225
1226         list_add_tail(&dev->list, &uvc_driver.devices);
1227         mutex_unlock(&uvc_driver.ctrl_mutex);
1228
1229         return 0;
1230 }
1231
1232 /*
1233  * Cleanup device controls.
1234  */
1235 void uvc_ctrl_cleanup_device(struct uvc_device *dev)
1236 {
1237         struct uvc_entity *entity;
1238         unsigned int i;
1239
1240         /* Remove the device from the global devices list */
1241         mutex_lock(&uvc_driver.ctrl_mutex);
1242         if (dev->list.next != NULL)
1243                 list_del(&dev->list);
1244         mutex_unlock(&uvc_driver.ctrl_mutex);
1245
1246         list_for_each_entry(entity, &dev->entities, list) {
1247                 for (i = 0; i < entity->ncontrols; ++i)
1248                         kfree(entity->controls[i].data);
1249
1250                 kfree(entity->controls);
1251         }
1252 }
1253
1254 void uvc_ctrl_init(void)
1255 {
1256         struct uvc_control_info *ctrl = uvc_ctrls;
1257         struct uvc_control_info *cend = ctrl + ARRAY_SIZE(uvc_ctrls);
1258         struct uvc_control_mapping *mapping = uvc_ctrl_mappings;
1259         struct uvc_control_mapping *mend =
1260                 mapping + ARRAY_SIZE(uvc_ctrl_mappings);
1261
1262         for (; ctrl < cend; ++ctrl)
1263                 uvc_ctrl_add_info(ctrl);
1264
1265         for (; mapping < mend; ++mapping)
1266                 uvc_ctrl_add_mapping(mapping);
1267 }
1268