drivers/media/video/v4l2-ctrls.c

   1 /*
   2     V4L2 controls framework implementation.
   3
   4     Copyright (C) 2010  Hans Verkuil <hverkuil@xs4all.nl>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <linux/ctype.h>
  22 #include <linux/slab.h>
  23 #include <media/v4l2-ioctl.h>
  24 #include <media/v4l2-device.h>
  25 #include <media/v4l2-ctrls.h>
  26 #include <media/v4l2-event.h>
  27 #include <media/v4l2-dev.h>
  28
  29 #define has_op(master, op) \
  30         (master->ops && master->ops->op)
  31 #define call_op(master, op) \
  32         (has_op(master, op) ? master->ops->op(master) : 0)
  33
  34 /* Internal temporary helper struct, one for each v4l2_ext_control */
  35 struct v4l2_ctrl_helper {
  36         /* Pointer to the control reference of the master control */
  37         struct v4l2_ctrl_ref *mref;
  38         /* The control corresponding to the v4l2_ext_control ID field. */
  39         struct v4l2_ctrl *ctrl;
  40         /* v4l2_ext_control index of the next control belonging to the
  41            same cluster, or 0 if there isn't any. */
  42         u32 next;
  43 };
  44
  45 /* Small helper function to determine if the autocluster is set to manual
  46    mode. In that case the is_volatile flag should be ignored. */
  47 static bool is_cur_manual(const struct v4l2_ctrl *master)
  48 {
  49         return master->is_auto && master->cur.val == master->manual_mode_value;
  50 }
  51
  52 /* Same as above, but this checks the against the new value instead of the
  53    current value. */
  54 static bool is_new_manual(const struct v4l2_ctrl *master)
  55 {
  56         return master->is_auto && master->val == master->manual_mode_value;
  57 }
  58
  59 /* Returns NULL or a character pointer array containing the menu for
  60    the given control ID. The pointer array ends with a NULL pointer.
  61    An empty string signifies a menu entry that is invalid. This allows
  62    drivers to disable certain options if it is not supported. */
  63 const char * const *v4l2_ctrl_get_menu(u32 id)
  64 {
  65         static const char * const mpeg_audio_sampling_freq[] = {
  66                 "44.1 kHz",
  67                 "48 kHz",
  68                 "32 kHz",
  69                 NULL
  70         };
  71         static const char * const mpeg_audio_encoding[] = {
  72                 "MPEG-1/2 Layer I",
  73                 "MPEG-1/2 Layer II",
  74                 "MPEG-1/2 Layer III",
  75                 "MPEG-2/4 AAC",
  76                 "AC-3",
  77                 NULL
  78         };
  79         static const char * const mpeg_audio_l1_bitrate[] = {
  80                 "32 kbps",
  81                 "64 kbps",
  82                 "96 kbps",
  83                 "128 kbps",
  84                 "160 kbps",
  85                 "192 kbps",
  86                 "224 kbps",
  87                 "256 kbps",
  88                 "288 kbps",
  89                 "320 kbps",
  90                 "352 kbps",
  91                 "384 kbps",
  92                 "416 kbps",
  93                 "448 kbps",
  94                 NULL
  95         };
  96         static const char * const mpeg_audio_l2_bitrate[] = {
  97                 "32 kbps",
  98                 "48 kbps",
  99                 "56 kbps",
 100                 "64 kbps",
 101                 "80 kbps",
 102                 "96 kbps",
 103                 "112 kbps",
 104                 "128 kbps",
 105                 "160 kbps",
 106                 "192 kbps",
 107                 "224 kbps",
 108                 "256 kbps",
 109                 "320 kbps",
 110                 "384 kbps",
 111                 NULL
 112         };
 113         static const char * const mpeg_audio_l3_bitrate[] = {
 114                 "32 kbps",
 115                 "40 kbps",
 116                 "48 kbps",
 117                 "56 kbps",
 118                 "64 kbps",
 119                 "80 kbps",
 120                 "96 kbps",
 121                 "112 kbps",
 122                 "128 kbps",
 123                 "160 kbps",
 124                 "192 kbps",
 125                 "224 kbps",
 126                 "256 kbps",
 127                 "320 kbps",
 128                 NULL
 129         };
 130         static const char * const mpeg_audio_ac3_bitrate[] = {
 131                 "32 kbps",
 132                 "40 kbps",
 133                 "48 kbps",
 134                 "56 kbps",
 135                 "64 kbps",
 136                 "80 kbps",
 137                 "96 kbps",
 138                 "112 kbps",
 139                 "128 kbps",
 140                 "160 kbps",
 141                 "192 kbps",
 142                 "224 kbps",
 143                 "256 kbps",
 144                 "320 kbps",
 145                 "384 kbps",
 146                 "448 kbps",
 147                 "512 kbps",
 148                 "576 kbps",
 149                 "640 kbps",
 150                 NULL
 151         };
 152         static const char * const mpeg_audio_mode[] = {
 153                 "Stereo",
 154                 "Joint Stereo",
 155                 "Dual",
 156                 "Mono",
 157                 NULL
 158         };
 159         static const char * const mpeg_audio_mode_extension[] = {
 160                 "Bound 4",
 161                 "Bound 8",
 162                 "Bound 12",
 163                 "Bound 16",
 164                 NULL
 165         };
 166         static const char * const mpeg_audio_emphasis[] = {
 167                 "No Emphasis",
 168                 "50/15 us",
 169                 "CCITT J17",
 170                 NULL
 171         };
 172         static const char * const mpeg_audio_crc[] = {
 173                 "No CRC",
 174                 "16-bit CRC",
 175                 NULL
 176         };
 177         static const char * const mpeg_video_encoding[] = {
 178                 "MPEG-1",
 179                 "MPEG-2",
 180                 "MPEG-4 AVC",
 181                 NULL
 182         };
 183         static const char * const mpeg_video_aspect[] = {
 184                 "1x1",
 185                 "4x3",
 186                 "16x9",
 187                 "2.21x1",
 188                 NULL
 189         };
 190         static const char * const mpeg_video_bitrate_mode[] = {
 191                 "Variable Bitrate",
 192                 "Constant Bitrate",
 193                 NULL
 194         };
 195         static const char * const mpeg_stream_type[] = {
 196                 "MPEG-2 Program Stream",
 197                 "MPEG-2 Transport Stream",
 198                 "MPEG-1 System Stream",
 199                 "MPEG-2 DVD-compatible Stream",
 200                 "MPEG-1 VCD-compatible Stream",
 201                 "MPEG-2 SVCD-compatible Stream",
 202                 NULL
 203         };
 204         static const char * const mpeg_stream_vbi_fmt[] = {
 205                 "No VBI",
 206                 "Private packet, IVTV format",
 207                 NULL
 208         };
 209         static const char * const camera_power_line_frequency[] = {
 210                 "Disabled",
 211                 "50 Hz",
 212                 "60 Hz",
 213                 NULL
 214         };
 215         static const char * const camera_exposure_auto[] = {
 216                 "Auto Mode",
 217                 "Manual Mode",
 218                 "Shutter Priority Mode",
 219                 "Aperture Priority Mode",
 220                 NULL
 221         };
 222         static const char * const colorfx[] = {
 223                 "None",
 224                 "Black & White",
 225                 "Sepia",
 226                 "Negative",
 227                 "Emboss",
 228                 "Sketch",
 229                 "Sky blue",
 230                 "Grass green",
 231                 "Skin whiten",
 232                 "Vivid",
 233                 NULL
 234         };
 235         static const char * const tune_preemphasis[] = {
 236                 "No preemphasis",
 237                 "50 useconds",
 238                 "75 useconds",
 239                 NULL,
 240         };
 241
 242         switch (id) {
 243         case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
 244                 return mpeg_audio_sampling_freq;
 245         case V4L2_CID_MPEG_AUDIO_ENCODING:
 246                 return mpeg_audio_encoding;
 247         case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
 248                 return mpeg_audio_l1_bitrate;
 249         case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
 250                 return mpeg_audio_l2_bitrate;
 251         case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
 252                 return mpeg_audio_l3_bitrate;
 253         case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
 254                 return mpeg_audio_ac3_bitrate;
 255         case V4L2_CID_MPEG_AUDIO_MODE:
 256                 return mpeg_audio_mode;
 257         case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
 258                 return mpeg_audio_mode_extension;
 259         case V4L2_CID_MPEG_AUDIO_EMPHASIS:
 260                 return mpeg_audio_emphasis;
 261         case V4L2_CID_MPEG_AUDIO_CRC:
 262                 return mpeg_audio_crc;
 263         case V4L2_CID_MPEG_VIDEO_ENCODING:
 264                 return mpeg_video_encoding;
 265         case V4L2_CID_MPEG_VIDEO_ASPECT:
 266                 return mpeg_video_aspect;
 267         case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
 268                 return mpeg_video_bitrate_mode;
 269         case V4L2_CID_MPEG_STREAM_TYPE:
 270                 return mpeg_stream_type;
 271         case V4L2_CID_MPEG_STREAM_VBI_FMT:
 272                 return mpeg_stream_vbi_fmt;
 273         case V4L2_CID_POWER_LINE_FREQUENCY:
 274                 return camera_power_line_frequency;
 275         case V4L2_CID_EXPOSURE_AUTO:
 276                 return camera_exposure_auto;
 277         case V4L2_CID_COLORFX:
 278                 return colorfx;
 279         case V4L2_CID_TUNE_PREEMPHASIS:
 280                 return tune_preemphasis;
 281         default:
 282                 return NULL;
 283         }
 284 }
 285 EXPORT_SYMBOL(v4l2_ctrl_get_menu);
 286
 287 /* Return the control name. */
 288 const char *v4l2_ctrl_get_name(u32 id)
 289 {
 290         switch (id) {
 291         /* USER controls */
 292         /* Keep the order of the 'case's the same as in videodev2.h! */
 293         case V4L2_CID_USER_CLASS:               return "User Controls";
 294         case V4L2_CID_BRIGHTNESS:               return "Brightness";
 295         case V4L2_CID_CONTRAST:                 return "Contrast";
 296         case V4L2_CID_SATURATION:               return "Saturation";
 297         case V4L2_CID_HUE:                      return "Hue";
 298         case V4L2_CID_AUDIO_VOLUME:             return "Volume";
 299         case V4L2_CID_AUDIO_BALANCE:            return "Balance";
 300         case V4L2_CID_AUDIO_BASS:               return "Bass";
 301         case V4L2_CID_AUDIO_TREBLE:             return "Treble";
 302         case V4L2_CID_AUDIO_MUTE:               return "Mute";
 303         case V4L2_CID_AUDIO_LOUDNESS:           return "Loudness";
 304         case V4L2_CID_BLACK_LEVEL:              return "Black Level";
 305         case V4L2_CID_AUTO_WHITE_BALANCE:       return "White Balance, Automatic";
 306         case V4L2_CID_DO_WHITE_BALANCE:         return "Do White Balance";
 307         case V4L2_CID_RED_BALANCE:              return "Red Balance";
 308         case V4L2_CID_BLUE_BALANCE:             return "Blue Balance";
 309         case V4L2_CID_GAMMA:                    return "Gamma";
 310         case V4L2_CID_EXPOSURE:                 return "Exposure";
 311         case V4L2_CID_AUTOGAIN:                 return "Gain, Automatic";
 312         case V4L2_CID_GAIN:                     return "Gain";
 313         case V4L2_CID_HFLIP:                    return "Horizontal Flip";
 314         case V4L2_CID_VFLIP:                    return "Vertical Flip";
 315         case V4L2_CID_HCENTER:                  return "Horizontal Center";
 316         case V4L2_CID_VCENTER:                  return "Vertical Center";
 317         case V4L2_CID_POWER_LINE_FREQUENCY:     return "Power Line Frequency";
 318         case V4L2_CID_HUE_AUTO:                 return "Hue, Automatic";
 319         case V4L2_CID_WHITE_BALANCE_TEMPERATURE: return "White Balance Temperature";
 320         case V4L2_CID_SHARPNESS:                return "Sharpness";
 321         case V4L2_CID_BACKLIGHT_COMPENSATION:   return "Backlight Compensation";
 322         case V4L2_CID_CHROMA_AGC:               return "Chroma AGC";
 323         case V4L2_CID_COLOR_KILLER:             return "Color Killer";
 324         case V4L2_CID_COLORFX:                  return "Color Effects";
 325         case V4L2_CID_AUTOBRIGHTNESS:           return "Brightness, Automatic";
 326         case V4L2_CID_BAND_STOP_FILTER:         return "Band-Stop Filter";
 327         case V4L2_CID_ROTATE:                   return "Rotate";
 328         case V4L2_CID_BG_COLOR:                 return "Background Color";
 329         case V4L2_CID_CHROMA_GAIN:              return "Chroma Gain";
 330         case V4L2_CID_ILLUMINATORS_1:           return "Illuminator 1";
 331         case V4L2_CID_ILLUMINATORS_2:           return "Illuminator 2";
 332
 333         /* MPEG controls */
 334         /* Keep the order of the 'case's the same as in videodev2.h! */
 335         case V4L2_CID_MPEG_CLASS:               return "MPEG Encoder Controls";
 336         case V4L2_CID_MPEG_STREAM_TYPE:         return "Stream Type";
 337         case V4L2_CID_MPEG_STREAM_PID_PMT:      return "Stream PMT Program ID";
 338         case V4L2_CID_MPEG_STREAM_PID_AUDIO:    return "Stream Audio Program ID";
 339         case V4L2_CID_MPEG_STREAM_PID_VIDEO:    return "Stream Video Program ID";
 340         case V4L2_CID_MPEG_STREAM_PID_PCR:      return "Stream PCR Program ID";
 341         case V4L2_CID_MPEG_STREAM_PES_ID_AUDIO: return "Stream PES Audio ID";
 342         case V4L2_CID_MPEG_STREAM_PES_ID_VIDEO: return "Stream PES Video ID";
 343         case V4L2_CID_MPEG_STREAM_VBI_FMT:      return "Stream VBI Format";
 344         case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ: return "Audio Sampling Frequency";
 345         case V4L2_CID_MPEG_AUDIO_ENCODING:      return "Audio Encoding";
 346         case V4L2_CID_MPEG_AUDIO_L1_BITRATE:    return "Audio Layer I Bitrate";
 347         case V4L2_CID_MPEG_AUDIO_L2_BITRATE:    return "Audio Layer II Bitrate";
 348         case V4L2_CID_MPEG_AUDIO_L3_BITRATE:    return "Audio Layer III Bitrate";
 349         case V4L2_CID_MPEG_AUDIO_MODE:          return "Audio Stereo Mode";
 350         case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION: return "Audio Stereo Mode Extension";
 351         case V4L2_CID_MPEG_AUDIO_EMPHASIS:      return "Audio Emphasis";
 352         case V4L2_CID_MPEG_AUDIO_CRC:           return "Audio CRC";
 353         case V4L2_CID_MPEG_AUDIO_MUTE:          return "Audio Mute";
 354         case V4L2_CID_MPEG_AUDIO_AAC_BITRATE:   return "Audio AAC Bitrate";
 355         case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:   return "Audio AC-3 Bitrate";
 356         case V4L2_CID_MPEG_VIDEO_ENCODING:      return "Video Encoding";
 357         case V4L2_CID_MPEG_VIDEO_ASPECT:        return "Video Aspect";
 358         case V4L2_CID_MPEG_VIDEO_B_FRAMES:      return "Video B Frames";
 359         case V4L2_CID_MPEG_VIDEO_GOP_SIZE:      return "Video GOP Size";
 360         case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE:   return "Video GOP Closure";
 361         case V4L2_CID_MPEG_VIDEO_PULLDOWN:      return "Video Pulldown";
 362         case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:  return "Video Bitrate Mode";
 363         case V4L2_CID_MPEG_VIDEO_BITRATE:       return "Video Bitrate";
 364         case V4L2_CID_MPEG_VIDEO_BITRATE_PEAK:  return "Video Peak Bitrate";
 365         case V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION: return "Video Temporal Decimation";
 366         case V4L2_CID_MPEG_VIDEO_MUTE:          return "Video Mute";
 367         case V4L2_CID_MPEG_VIDEO_MUTE_YUV:      return "Video Mute YUV";
 368
 369         /* CAMERA controls */
 370         /* Keep the order of the 'case's the same as in videodev2.h! */
 371         case V4L2_CID_CAMERA_CLASS:             return "Camera Controls";
 372         case V4L2_CID_EXPOSURE_AUTO:            return "Auto Exposure";
 373         case V4L2_CID_EXPOSURE_ABSOLUTE:        return "Exposure Time, Absolute";
 374         case V4L2_CID_EXPOSURE_AUTO_PRIORITY:   return "Exposure, Dynamic Framerate";
 375         case V4L2_CID_PAN_RELATIVE:             return "Pan, Relative";
 376         case V4L2_CID_TILT_RELATIVE:            return "Tilt, Relative";
 377         case V4L2_CID_PAN_RESET:                return "Pan, Reset";
 378         case V4L2_CID_TILT_RESET:               return "Tilt, Reset";
 379         case V4L2_CID_PAN_ABSOLUTE:             return "Pan, Absolute";
 380         case V4L2_CID_TILT_ABSOLUTE:            return "Tilt, Absolute";
 381         case V4L2_CID_FOCUS_ABSOLUTE:           return "Focus, Absolute";
 382         case V4L2_CID_FOCUS_RELATIVE:           return "Focus, Relative";
 383         case V4L2_CID_FOCUS_AUTO:               return "Focus, Automatic";
 384         case V4L2_CID_ZOOM_ABSOLUTE:            return "Zoom, Absolute";
 385         case V4L2_CID_ZOOM_RELATIVE:            return "Zoom, Relative";
 386         case V4L2_CID_ZOOM_CONTINUOUS:          return "Zoom, Continuous";
 387         case V4L2_CID_PRIVACY:                  return "Privacy";
 388         case V4L2_CID_IRIS_ABSOLUTE:            return "Iris, Absolute";
 389         case V4L2_CID_IRIS_RELATIVE:            return "Iris, Relative";
 390
 391         /* FM Radio Modulator control */
 392         /* Keep the order of the 'case's the same as in videodev2.h! */
 393         case V4L2_CID_FM_TX_CLASS:              return "FM Radio Modulator Controls";
 394         case V4L2_CID_RDS_TX_DEVIATION:         return "RDS Signal Deviation";
 395         case V4L2_CID_RDS_TX_PI:                return "RDS Program ID";
 396         case V4L2_CID_RDS_TX_PTY:               return "RDS Program Type";
 397         case V4L2_CID_RDS_TX_PS_NAME:           return "RDS PS Name";
 398         case V4L2_CID_RDS_TX_RADIO_TEXT:        return "RDS Radio Text";
 399         case V4L2_CID_AUDIO_LIMITER_ENABLED:    return "Audio Limiter Feature Enabled";
 400         case V4L2_CID_AUDIO_LIMITER_RELEASE_TIME: return "Audio Limiter Release Time";
 401         case V4L2_CID_AUDIO_LIMITER_DEVIATION:  return "Audio Limiter Deviation";
 402         case V4L2_CID_AUDIO_COMPRESSION_ENABLED: return "Audio Compression Feature Enabled";
 403         case V4L2_CID_AUDIO_COMPRESSION_GAIN:   return "Audio Compression Gain";
 404         case V4L2_CID_AUDIO_COMPRESSION_THRESHOLD: return "Audio Compression Threshold";
 405         case V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME: return "Audio Compression Attack Time";
 406         case V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME: return "Audio Compression Release Time";
 407         case V4L2_CID_PILOT_TONE_ENABLED:       return "Pilot Tone Feature Enabled";
 408         case V4L2_CID_PILOT_TONE_DEVIATION:     return "Pilot Tone Deviation";
 409         case V4L2_CID_PILOT_TONE_FREQUENCY:     return "Pilot Tone Frequency";
 410         case V4L2_CID_TUNE_PREEMPHASIS:         return "Pre-emphasis settings";
 411         case V4L2_CID_TUNE_POWER_LEVEL:         return "Tune Power Level";
 412         case V4L2_CID_TUNE_ANTENNA_CAPACITOR:   return "Tune Antenna Capacitor";
 413
 414         default:
 415                 return NULL;
 416         }
 417 }
 418 EXPORT_SYMBOL(v4l2_ctrl_get_name);
 419
 420 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 421                     s32 *min, s32 *max, s32 *step, s32 *def, u32 *flags)
 422 {
 423         *name = v4l2_ctrl_get_name(id);
 424         *flags = 0;
 425
 426         switch (id) {
 427         case V4L2_CID_AUDIO_MUTE:
 428         case V4L2_CID_AUDIO_LOUDNESS:
 429         case V4L2_CID_AUTO_WHITE_BALANCE:
 430         case V4L2_CID_AUTOGAIN:
 431         case V4L2_CID_HFLIP:
 432         case V4L2_CID_VFLIP:
 433         case V4L2_CID_HUE_AUTO:
 434         case V4L2_CID_CHROMA_AGC:
 435         case V4L2_CID_COLOR_KILLER:
 436         case V4L2_CID_MPEG_AUDIO_MUTE:
 437         case V4L2_CID_MPEG_VIDEO_MUTE:
 438         case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE:
 439         case V4L2_CID_MPEG_VIDEO_PULLDOWN:
 440         case V4L2_CID_EXPOSURE_AUTO_PRIORITY:
 441         case V4L2_CID_FOCUS_AUTO:
 442         case V4L2_CID_PRIVACY:
 443         case V4L2_CID_AUDIO_LIMITER_ENABLED:
 444         case V4L2_CID_AUDIO_COMPRESSION_ENABLED:
 445         case V4L2_CID_PILOT_TONE_ENABLED:
 446         case V4L2_CID_ILLUMINATORS_1:
 447         case V4L2_CID_ILLUMINATORS_2:
 448                 *type = V4L2_CTRL_TYPE_BOOLEAN;
 449                 *min = 0;
 450                 *max = *step = 1;
 451                 break;
 452         case V4L2_CID_PAN_RESET:
 453         case V4L2_CID_TILT_RESET:
 454                 *type = V4L2_CTRL_TYPE_BUTTON;
 455                 *flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
 456                 *min = *max = *step = *def = 0;
 457                 break;
 458         case V4L2_CID_POWER_LINE_FREQUENCY:
 459         case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
 460         case V4L2_CID_MPEG_AUDIO_ENCODING:
 461         case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
 462         case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
 463         case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
 464         case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
 465         case V4L2_CID_MPEG_AUDIO_MODE:
 466         case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
 467         case V4L2_CID_MPEG_AUDIO_EMPHASIS:
 468         case V4L2_CID_MPEG_AUDIO_CRC:
 469         case V4L2_CID_MPEG_VIDEO_ENCODING:
 470         case V4L2_CID_MPEG_VIDEO_ASPECT:
 471         case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
 472         case V4L2_CID_MPEG_STREAM_TYPE:
 473         case V4L2_CID_MPEG_STREAM_VBI_FMT:
 474         case V4L2_CID_EXPOSURE_AUTO:
 475         case V4L2_CID_COLORFX:
 476         case V4L2_CID_TUNE_PREEMPHASIS:
 477                 *type = V4L2_CTRL_TYPE_MENU;
 478                 break;
 479         case V4L2_CID_RDS_TX_PS_NAME:
 480         case V4L2_CID_RDS_TX_RADIO_TEXT:
 481                 *type = V4L2_CTRL_TYPE_STRING;
 482                 break;
 483         case V4L2_CID_USER_CLASS:
 484         case V4L2_CID_CAMERA_CLASS:
 485         case V4L2_CID_MPEG_CLASS:
 486         case V4L2_CID_FM_TX_CLASS:
 487                 *type = V4L2_CTRL_TYPE_CTRL_CLASS;
 488                 /* You can neither read not write these */
 489                 *flags |= V4L2_CTRL_FLAG_READ_ONLY | V4L2_CTRL_FLAG_WRITE_ONLY;
 490                 *min = *max = *step = *def = 0;
 491                 break;
 492         case V4L2_CID_BG_COLOR:
 493                 *type = V4L2_CTRL_TYPE_INTEGER;
 494                 *step = 1;
 495                 *min = 0;
 496                 /* Max is calculated as RGB888 that is 2^24 */
 497                 *max = 0xFFFFFF;
 498                 break;
 499         default:
 500                 *type = V4L2_CTRL_TYPE_INTEGER;
 501                 break;
 502         }
 503         switch (id) {
 504         case V4L2_CID_MPEG_AUDIO_ENCODING:
 505         case V4L2_CID_MPEG_AUDIO_MODE:
 506         case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
 507         case V4L2_CID_MPEG_VIDEO_B_FRAMES:
 508         case V4L2_CID_MPEG_STREAM_TYPE:
 509                 *flags |= V4L2_CTRL_FLAG_UPDATE;
 510                 break;
 511         case V4L2_CID_AUDIO_VOLUME:
 512         case V4L2_CID_AUDIO_BALANCE:
 513         case V4L2_CID_AUDIO_BASS:
 514         case V4L2_CID_AUDIO_TREBLE:
 515         case V4L2_CID_BRIGHTNESS:
 516         case V4L2_CID_CONTRAST:
 517         case V4L2_CID_SATURATION:
 518         case V4L2_CID_HUE:
 519         case V4L2_CID_RED_BALANCE:
 520         case V4L2_CID_BLUE_BALANCE:
 521         case V4L2_CID_GAMMA:
 522         case V4L2_CID_SHARPNESS:
 523         case V4L2_CID_CHROMA_GAIN:
 524         case V4L2_CID_RDS_TX_DEVIATION:
 525         case V4L2_CID_AUDIO_LIMITER_RELEASE_TIME:
 526         case V4L2_CID_AUDIO_LIMITER_DEVIATION:
 527         case V4L2_CID_AUDIO_COMPRESSION_GAIN:
 528         case V4L2_CID_AUDIO_COMPRESSION_THRESHOLD:
 529         case V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME:
 530         case V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME:
 531         case V4L2_CID_PILOT_TONE_DEVIATION:
 532         case V4L2_CID_PILOT_TONE_FREQUENCY:
 533         case V4L2_CID_TUNE_POWER_LEVEL:
 534         case V4L2_CID_TUNE_ANTENNA_CAPACITOR:
 535                 *flags |= V4L2_CTRL_FLAG_SLIDER;
 536                 break;
 537         case V4L2_CID_PAN_RELATIVE:
 538         case V4L2_CID_TILT_RELATIVE:
 539         case V4L2_CID_FOCUS_RELATIVE:
 540         case V4L2_CID_IRIS_RELATIVE:
 541         case V4L2_CID_ZOOM_RELATIVE:
 542                 *flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
 543                 break;
 544         }
 545 }
 546 EXPORT_SYMBOL(v4l2_ctrl_fill);
 547
 548 /* Helper function to determine whether the control type is compatible with
 549    VIDIOC_G/S_CTRL. */
 550 static bool type_is_int(const struct v4l2_ctrl *ctrl)
 551 {
 552         switch (ctrl->type) {
 553         case V4L2_CTRL_TYPE_INTEGER64:
 554         case V4L2_CTRL_TYPE_STRING:
 555                 /* Nope, these need v4l2_ext_control */
 556                 return false;
 557         default:
 558                 return true;
 559         }
 560 }
 561
 562 static void fill_event(struct v4l2_event *ev, struct v4l2_ctrl *ctrl, u32 changes)
 563 {
 564         memset(ev->reserved, 0, sizeof(ev->reserved));
 565         ev->type = V4L2_EVENT_CTRL;
 566         ev->id = ctrl->id;
 567         ev->u.ctrl.changes = changes;
 568         ev->u.ctrl.type = ctrl->type;
 569         ev->u.ctrl.flags = ctrl->flags;
 570         if (ctrl->type == V4L2_CTRL_TYPE_STRING)
 571                 ev->u.ctrl.value64 = 0;
 572         else
 573                 ev->u.ctrl.value64 = ctrl->cur.val64;
 574         ev->u.ctrl.minimum = ctrl->minimum;
 575         ev->u.ctrl.maximum = ctrl->maximum;
 576         if (ctrl->type == V4L2_CTRL_TYPE_MENU)
 577                 ev->u.ctrl.step = 1;
 578         else
 579                 ev->u.ctrl.step = ctrl->step;
 580         ev->u.ctrl.default_value = ctrl->default_value;
 581 }
 582
 583 static void send_event(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, u32 changes)
 584 {
 585         struct v4l2_event ev;
 586         struct v4l2_subscribed_event *sev;
 587
 588         if (list_empty(&ctrl->ev_subs))
 589                 return;
 590         fill_event(&ev, ctrl, changes);
 591
 592         list_for_each_entry(sev, &ctrl->ev_subs, node)
 593                 if (sev->fh && (sev->fh != fh ||
 594                                 (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK)))
 595                         v4l2_event_queue_fh(sev->fh, &ev);
 596 }
 597
 598 /* Helper function: copy the current control value back to the caller */
 599 static int cur_to_user(struct v4l2_ext_control *c,
 600                        struct v4l2_ctrl *ctrl)
 601 {
 602         u32 len;
 603
 604         switch (ctrl->type) {
 605         case V4L2_CTRL_TYPE_STRING:
 606                 len = strlen(ctrl->cur.string);
 607                 if (c->size < len + 1) {
 608                         c->size = len + 1;
 609                         return -ENOSPC;
 610                 }
 611                 return copy_to_user(c->string, ctrl->cur.string,
 612                                                 len + 1) ? -EFAULT : 0;
 613         case V4L2_CTRL_TYPE_INTEGER64:
 614                 c->value64 = ctrl->cur.val64;
 615                 break;
 616         default:
 617                 c->value = ctrl->cur.val;
 618                 break;
 619         }
 620         return 0;
 621 }
 622
 623 /* Helper function: copy the caller-provider value as the new control value */
 624 static int user_to_new(struct v4l2_ext_control *c,
 625                        struct v4l2_ctrl *ctrl)
 626 {
 627         int ret;
 628         u32 size;
 629
 630         ctrl->is_new = 1;
 631         switch (ctrl->type) {
 632         case V4L2_CTRL_TYPE_INTEGER64:
 633                 ctrl->val64 = c->value64;
 634                 break;
 635         case V4L2_CTRL_TYPE_STRING:
 636                 size = c->size;
 637                 if (size == 0)
 638                         return -ERANGE;
 639                 if (size > ctrl->maximum + 1)
 640                         size = ctrl->maximum + 1;
 641                 ret = copy_from_user(ctrl->string, c->string, size);
 642                 if (!ret) {
 643                         char last = ctrl->string[size - 1];
 644
 645                         ctrl->string[size - 1] = 0;
 646                         /* If the string was longer than ctrl->maximum,
 647                            then return an error. */
 648                         if (strlen(ctrl->string) == ctrl->maximum && last)
 649                                 return -ERANGE;
 650                 }
 651                 return ret ? -EFAULT : 0;
 652         default:
 653                 ctrl->val = c->value;
 654                 break;
 655         }
 656         return 0;
 657 }
 658
 659 /* Helper function: copy the new control value back to the caller */
 660 static int new_to_user(struct v4l2_ext_control *c,
 661                        struct v4l2_ctrl *ctrl)
 662 {
 663         u32 len;
 664
 665         switch (ctrl->type) {
 666         case V4L2_CTRL_TYPE_STRING:
 667                 len = strlen(ctrl->string);
 668                 if (c->size < len + 1) {
 669                         c->size = ctrl->maximum + 1;
 670                         return -ENOSPC;
 671                 }
 672                 return copy_to_user(c->string, ctrl->string,
 673                                                 len + 1) ? -EFAULT : 0;
 674         case V4L2_CTRL_TYPE_INTEGER64:
 675                 c->value64 = ctrl->val64;
 676                 break;
 677         default:
 678                 c->value = ctrl->val;
 679                 break;
 680         }
 681         return 0;
 682 }
 683
 684 /* Copy the new value to the current value. */
 685 static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl,
 686                                                 bool update_inactive)
 687 {
 688         bool changed = false;
 689
 690         if (ctrl == NULL)
 691                 return;
 692         switch (ctrl->type) {
 693         case V4L2_CTRL_TYPE_BUTTON:
 694                 changed = true;
 695                 break;
 696         case V4L2_CTRL_TYPE_STRING:
 697                 /* strings are always 0-terminated */
 698                 changed = strcmp(ctrl->string, ctrl->cur.string);
 699                 strcpy(ctrl->cur.string, ctrl->string);
 700                 break;
 701         case V4L2_CTRL_TYPE_INTEGER64:
 702                 changed = ctrl->val64 != ctrl->cur.val64;
 703                 ctrl->cur.val64 = ctrl->val64;
 704                 break;
 705         default:
 706                 changed = ctrl->val != ctrl->cur.val;
 707                 ctrl->cur.val = ctrl->val;
 708                 break;
 709         }
 710         if (update_inactive) {
 711                 ctrl->flags &= ~V4L2_CTRL_FLAG_INACTIVE;
 712                 if (!is_cur_manual(ctrl->cluster[0]))
 713                         ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
 714         }
 715         if (changed || update_inactive) {
 716                 /* If a control was changed that was not one of the controls
 717                    modified by the application, then send the event to all. */
 718                 if (!ctrl->is_new)
 719                         fh = NULL;
 720                 send_event(fh, ctrl,
 721                         (changed ? V4L2_EVENT_CTRL_CH_VALUE : 0) |
 722                         (update_inactive ? V4L2_EVENT_CTRL_CH_FLAGS : 0));
 723         }
 724 }
 725
 726 /* Copy the current value to the new value */
 727 static void cur_to_new(struct v4l2_ctrl *ctrl)
 728 {
 729         if (ctrl == NULL)
 730                 return;
 731         switch (ctrl->type) {
 732         case V4L2_CTRL_TYPE_STRING:
 733                 /* strings are always 0-terminated */
 734                 strcpy(ctrl->string, ctrl->cur.string);
 735                 break;
 736         case V4L2_CTRL_TYPE_INTEGER64:
 737                 ctrl->val64 = ctrl->cur.val64;
 738                 break;
 739         default:
 740                 ctrl->val = ctrl->cur.val;
 741                 break;
 742         }
 743 }
 744
 745 /* Return non-zero if one or more of the controls in the cluster has a new
 746    value that differs from the current value. */
 747 static int cluster_changed(struct v4l2_ctrl *master)
 748 {
 749         int diff = 0;
 750         int i;
 751
 752         for (i = 0; !diff && i < master->ncontrols; i++) {
 753                 struct v4l2_ctrl *ctrl = master->cluster[i];
 754
 755                 if (ctrl == NULL)
 756                         continue;
 757                 switch (ctrl->type) {
 758                 case V4L2_CTRL_TYPE_BUTTON:
 759                         /* Button controls are always 'different' */
 760                         return 1;
 761                 case V4L2_CTRL_TYPE_STRING:
 762                         /* strings are always 0-terminated */
 763                         diff = strcmp(ctrl->string, ctrl->cur.string);
 764                         break;
 765                 case V4L2_CTRL_TYPE_INTEGER64:
 766                         diff = ctrl->val64 != ctrl->cur.val64;
 767                         break;
 768                 default:
 769                         diff = ctrl->val != ctrl->cur.val;
 770                         break;
 771                 }
 772         }
 773         return diff;
 774 }
 775
 776 /* Validate integer-type control */
 777 static int validate_new_int(const struct v4l2_ctrl *ctrl, s32 *pval)
 778 {
 779         s32 val = *pval;
 780         u32 offset;
 781
 782         switch (ctrl->type) {
 783         case V4L2_CTRL_TYPE_INTEGER:
 784                 /* Round towards the closest legal value */
 785                 val += ctrl->step / 2;
 786                 if (val < ctrl->minimum)
 787                         val = ctrl->minimum;
 788                 if (val > ctrl->maximum)
 789                         val = ctrl->maximum;
 790                 offset = val - ctrl->minimum;
 791                 offset = ctrl->step * (offset / ctrl->step);
 792                 val = ctrl->minimum + offset;
 793                 *pval = val;
 794                 return 0;
 795
 796         case V4L2_CTRL_TYPE_BOOLEAN:
 797                 *pval = !!val;
 798                 return 0;
 799
 800         case V4L2_CTRL_TYPE_MENU:
 801                 if (val < ctrl->minimum || val > ctrl->maximum)
 802                         return -ERANGE;
 803                 if (ctrl->qmenu[val][0] == '\0' ||
 804                     (ctrl->menu_skip_mask & (1 << val)))
 805                         return -EINVAL;
 806                 return 0;
 807
 808         case V4L2_CTRL_TYPE_BUTTON:
 809         case V4L2_CTRL_TYPE_CTRL_CLASS:
 810                 *pval = 0;
 811                 return 0;
 812
 813         default:
 814                 return -EINVAL;
 815         }
 816 }
 817
 818 /* Validate a new control */
 819 static int validate_new(const struct v4l2_ctrl *ctrl, struct v4l2_ext_control *c)
 820 {
 821         char *s = c->string;
 822         size_t len;
 823
 824         switch (ctrl->type) {
 825         case V4L2_CTRL_TYPE_INTEGER:
 826         case V4L2_CTRL_TYPE_BOOLEAN:
 827         case V4L2_CTRL_TYPE_MENU:
 828         case V4L2_CTRL_TYPE_BUTTON:
 829         case V4L2_CTRL_TYPE_CTRL_CLASS:
 830                 return validate_new_int(ctrl, &c->value);
 831
 832         case V4L2_CTRL_TYPE_INTEGER64:
 833                 return 0;
 834
 835         case V4L2_CTRL_TYPE_STRING:
 836                 len = strlen(s);
 837                 if (len < ctrl->minimum)
 838                         return -ERANGE;
 839                 if ((len - ctrl->minimum) % ctrl->step)
 840                         return -ERANGE;
 841                 return 0;
 842
 843         default:
 844                 return -EINVAL;
 845         }
 846 }
 847
 848 static inline u32 node2id(struct list_head *node)
 849 {
 850         return list_entry(node, struct v4l2_ctrl_ref, node)->ctrl->id;
 851 }
 852
 853 /* Set the handler's error code if it wasn't set earlier already */
 854 static inline int handler_set_err(struct v4l2_ctrl_handler *hdl, int err)
 855 {
 856         if (hdl->error == 0)
 857                 hdl->error = err;
 858         return err;
 859 }
 860
 861 /* Initialize the handler */
 862 int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler *hdl,
 863                            unsigned nr_of_controls_hint)
 864 {
 865         mutex_init(&hdl->lock);
 866         INIT_LIST_HEAD(&hdl->ctrls);
 867         INIT_LIST_HEAD(&hdl->ctrl_refs);
 868         hdl->nr_of_buckets = 1 + nr_of_controls_hint / 8;
 869         hdl->buckets = kzalloc(sizeof(hdl->buckets[0]) * hdl->nr_of_buckets,
 870                                                                 GFP_KERNEL);
 871         hdl->error = hdl->buckets ? 0 : -ENOMEM;
 872         return hdl->error;
 873 }
 874 EXPORT_SYMBOL(v4l2_ctrl_handler_init);
 875
 876 /* Free all controls and control refs */
 877 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl)
 878 {
 879         struct v4l2_ctrl_ref *ref, *next_ref;
 880         struct v4l2_ctrl *ctrl, *next_ctrl;
 881         struct v4l2_subscribed_event *sev, *next_sev;
 882
 883         if (hdl == NULL || hdl->buckets == NULL)
 884                 return;
 885
 886         mutex_lock(&hdl->lock);
 887         /* Free all nodes */
 888         list_for_each_entry_safe(ref, next_ref, &hdl->ctrl_refs, node) {
 889                 list_del(&ref->node);
 890                 kfree(ref);
 891         }
 892         /* Free all controls owned by the handler */
 893         list_for_each_entry_safe(ctrl, next_ctrl, &hdl->ctrls, node) {
 894                 list_del(&ctrl->node);
 895                 list_for_each_entry_safe(sev, next_sev, &ctrl->ev_subs, node)
 896                         list_del(&sev->node);
 897                 kfree(ctrl);
 898         }
 899         kfree(hdl->buckets);
 900         hdl->buckets = NULL;
 901         hdl->cached = NULL;
 902         hdl->error = 0;
 903         mutex_unlock(&hdl->lock);
 904 }
 905 EXPORT_SYMBOL(v4l2_ctrl_handler_free);
 906
 907 /* For backwards compatibility: V4L2_CID_PRIVATE_BASE should no longer
 908    be used except in G_CTRL, S_CTRL, QUERYCTRL and QUERYMENU when dealing
 909    with applications that do not use the NEXT_CTRL flag.
 910
 911    We just find the n-th private user control. It's O(N), but that should not
 912    be an issue in this particular case. */
 913 static struct v4l2_ctrl_ref *find_private_ref(
 914                 struct v4l2_ctrl_handler *hdl, u32 id)
 915 {
 916         struct v4l2_ctrl_ref *ref;
 917
 918         id -= V4L2_CID_PRIVATE_BASE;
 919         list_for_each_entry(ref, &hdl->ctrl_refs, node) {
 920                 /* Search for private user controls that are compatible with
 921                    VIDIOC_G/S_CTRL. */
 922                 if (V4L2_CTRL_ID2CLASS(ref->ctrl->id) == V4L2_CTRL_CLASS_USER &&
 923                     V4L2_CTRL_DRIVER_PRIV(ref->ctrl->id)) {
 924                         if (!type_is_int(ref->ctrl))
 925                                 continue;
 926                         if (id == 0)
 927                                 return ref;
 928                         id--;
 929                 }
 930         }
 931         return NULL;
 932 }
 933
 934 /* Find a control with the given ID. */
 935 static struct v4l2_ctrl_ref *find_ref(struct v4l2_ctrl_handler *hdl, u32 id)
 936 {
 937         struct v4l2_ctrl_ref *ref;
 938         int bucket;
 939
 940         id &= V4L2_CTRL_ID_MASK;
 941
 942         /* Old-style private controls need special handling */
 943         if (id >= V4L2_CID_PRIVATE_BASE)
 944                 return find_private_ref(hdl, id);
 945         bucket = id % hdl->nr_of_buckets;
 946
 947         /* Simple optimization: cache the last control found */
 948         if (hdl->cached && hdl->cached->ctrl->id == id)
 949                 return hdl->cached;
 950
 951         /* Not in cache, search the hash */
 952         ref = hdl->buckets ? hdl->buckets[bucket] : NULL;
 953         while (ref && ref->ctrl->id != id)
 954                 ref = ref->next;
 955
 956         if (ref)
 957                 hdl->cached = ref; /* cache it! */
 958         return ref;
 959 }
 960
 961 /* Find a control with the given ID. Take the handler's lock first. */
 962 static struct v4l2_ctrl_ref *find_ref_lock(
 963                 struct v4l2_ctrl_handler *hdl, u32 id)
 964 {
 965         struct v4l2_ctrl_ref *ref = NULL;
 966
 967         if (hdl) {
 968                 mutex_lock(&hdl->lock);
 969                 ref = find_ref(hdl, id);
 970                 mutex_unlock(&hdl->lock);
 971         }
 972         return ref;
 973 }
 974
 975 /* Find a control with the given ID. */
 976 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id)
 977 {
 978         struct v4l2_ctrl_ref *ref = find_ref_lock(hdl, id);
 979
 980         return ref ? ref->ctrl : NULL;
 981 }
 982 EXPORT_SYMBOL(v4l2_ctrl_find);
 983
 984 /* Allocate a new v4l2_ctrl_ref and hook it into the handler. */
 985 static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
 986                            struct v4l2_ctrl *ctrl)
 987 {
 988         struct v4l2_ctrl_ref *ref;
 989         struct v4l2_ctrl_ref *new_ref;
 990         u32 id = ctrl->id;
 991         u32 class_ctrl = V4L2_CTRL_ID2CLASS(id) | 1;
 992         int bucket = id % hdl->nr_of_buckets;   /* which bucket to use */
 993
 994         /* Automatically add the control class if it is not yet present. */
 995         if (id != class_ctrl && find_ref_lock(hdl, class_ctrl) == NULL)
 996                 if (!v4l2_ctrl_new_std(hdl, NULL, class_ctrl, 0, 0, 0, 0))
 997                         return hdl->error;
 998
 999         if (hdl->error)
1000                 return hdl->error;
1001
1002         new_ref = kzalloc(sizeof(*new_ref), GFP_KERNEL);
1003         if (!new_ref)
1004                 return handler_set_err(hdl, -ENOMEM);
1005         new_ref->ctrl = ctrl;
1006         if (ctrl->handler == hdl) {
1007                 /* By default each control starts in a cluster of its own.
1008                    new_ref->ctrl is basically a cluster array with one
1009                    element, so that's perfect to use as the cluster pointer.
1010                    But only do this for the handler that owns the control. */
1011                 ctrl->cluster = &new_ref->ctrl;
1012                 ctrl->ncontrols = 1;
1013         }
1014
1015         INIT_LIST_HEAD(&new_ref->node);
1016
1017         mutex_lock(&hdl->lock);
1018
1019         /* Add immediately at the end of the list if the list is empty, or if
1020            the last element in the list has a lower ID.
1021            This ensures that when elements are added in ascending order the
1022            insertion is an O(1) operation. */
1023         if (list_empty(&hdl->ctrl_refs) || id > node2id(hdl->ctrl_refs.prev)) {
1024                 list_add_tail(&new_ref->node, &hdl->ctrl_refs);
1025                 goto insert_in_hash;
1026         }
1027
1028         /* Find insert position in sorted list */
1029         list_for_each_entry(ref, &hdl->ctrl_refs, node) {
1030                 if (ref->ctrl->id < id)
1031                         continue;
1032                 /* Don't add duplicates */
1033                 if (ref->ctrl->id == id) {
1034                         kfree(new_ref);
1035                         goto unlock;
1036                 }
1037                 list_add(&new_ref->node, ref->node.prev);
1038                 break;
1039         }
1040
1041 insert_in_hash:
1042         /* Insert the control node in the hash */
1043         new_ref->next = hdl->buckets[bucket];
1044         hdl->buckets[bucket] = new_ref;
1045
1046 unlock:
1047         mutex_unlock(&hdl->lock);
1048         return 0;
1049 }
1050
1051 /* Add a new control */
1052 static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
1053                         const struct v4l2_ctrl_ops *ops,
1054                         u32 id, const char *name, enum v4l2_ctrl_type type,
1055                         s32 min, s32 max, u32 step, s32 def,
1056                         u32 flags, const char * const *qmenu, void *priv)
1057 {
1058         struct v4l2_ctrl *ctrl;
1059         unsigned sz_extra = 0;
1060
1061         if (hdl->error)
1062                 return NULL;
1063
1064         /* Sanity checks */
1065         if (id == 0 || name == NULL || id >= V4L2_CID_PRIVATE_BASE ||
1066             max < min ||
1067             (type == V4L2_CTRL_TYPE_INTEGER && step == 0) ||
1068             (type == V4L2_CTRL_TYPE_MENU && qmenu == NULL) ||
1069             (type == V4L2_CTRL_TYPE_STRING && max == 0)) {
1070                 handler_set_err(hdl, -ERANGE);
1071                 return NULL;
1072         }
1073         if ((type == V4L2_CTRL_TYPE_INTEGER ||
1074              type == V4L2_CTRL_TYPE_MENU ||
1075              type == V4L2_CTRL_TYPE_BOOLEAN) &&
1076             (def < min || def > max)) {
1077                 handler_set_err(hdl, -ERANGE);
1078                 return NULL;
1079         }
1080
1081         if (type == V4L2_CTRL_TYPE_BUTTON)
1082                 flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
1083         else if (type == V4L2_CTRL_TYPE_CTRL_CLASS)
1084                 flags |= V4L2_CTRL_FLAG_READ_ONLY;
1085         else if (type == V4L2_CTRL_TYPE_STRING)
1086                 sz_extra += 2 * (max + 1);
1087
1088         ctrl = kzalloc(sizeof(*ctrl) + sz_extra, GFP_KERNEL);
1089         if (ctrl == NULL) {
1090                 handler_set_err(hdl, -ENOMEM);
1091                 return NULL;
1092         }
1093
1094         INIT_LIST_HEAD(&ctrl->node);
1095         INIT_LIST_HEAD(&ctrl->ev_subs);
1096         ctrl->handler = hdl;
1097         ctrl->ops = ops;
1098         ctrl->id = id;
1099         ctrl->name = name;
1100         ctrl->type = type;
1101         ctrl->flags = flags;
1102         ctrl->minimum = min;
1103         ctrl->maximum = max;
1104         ctrl->step = step;
1105         ctrl->qmenu = qmenu;
1106         ctrl->priv = priv;
1107         ctrl->cur.val = ctrl->val = ctrl->default_value = def;
1108
1109         if (ctrl->type == V4L2_CTRL_TYPE_STRING) {
1110                 ctrl->cur.string = (char *)&ctrl[1] + sz_extra - (max + 1);
1111                 ctrl->string = (char *)&ctrl[1] + sz_extra - 2 * (max + 1);
1112                 if (ctrl->minimum)
1113                         memset(ctrl->cur.string, ' ', ctrl->minimum);
1114         }
1115         if (handler_new_ref(hdl, ctrl)) {
1116                 kfree(ctrl);
1117                 return NULL;
1118         }
1119         mutex_lock(&hdl->lock);
1120         list_add_tail(&ctrl->node, &hdl->ctrls);
1121         mutex_unlock(&hdl->lock);
1122         return ctrl;
1123 }
1124
1125 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
1126                         const struct v4l2_ctrl_config *cfg, void *priv)
1127 {
1128         bool is_menu;
1129         struct v4l2_ctrl *ctrl;
1130         const char *name = cfg->name;
1131         const char * const *qmenu = cfg->qmenu;
1132         enum v4l2_ctrl_type type = cfg->type;
1133         u32 flags = cfg->flags;
1134         s32 min = cfg->min;
1135         s32 max = cfg->max;
1136         u32 step = cfg->step;
1137         s32 def = cfg->def;
1138
1139         if (name == NULL)
1140                 v4l2_ctrl_fill(cfg->id, &name, &type, &min, &max, &step,
1141                                                                 &def, &flags);
1142
1143         is_menu = (cfg->type == V4L2_CTRL_TYPE_MENU);
1144         if (is_menu)
1145                 WARN_ON(step);
1146         else
1147                 WARN_ON(cfg->menu_skip_mask);
1148         if (is_menu && qmenu == NULL)
1149                 qmenu = v4l2_ctrl_get_menu(cfg->id);
1150
1151         ctrl = v4l2_ctrl_new(hdl, cfg->ops, cfg->id, name,
1152                         type, min, max,
1153                         is_menu ? cfg->menu_skip_mask : step,
1154                         def, flags, qmenu, priv);
1155         if (ctrl) {
1156                 ctrl->is_private = cfg->is_private;
1157                 ctrl->is_volatile = cfg->is_volatile;
1158         }
1159         return ctrl;
1160 }
1161 EXPORT_SYMBOL(v4l2_ctrl_new_custom);
1162
1163 /* Helper function for standard non-menu controls */
1164 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
1165                         const struct v4l2_ctrl_ops *ops,
1166                         u32 id, s32 min, s32 max, u32 step, s32 def)
1167 {
1168         const char *name;
1169         enum v4l2_ctrl_type type;
1170         u32 flags;
1171
1172         v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1173         if (type == V4L2_CTRL_TYPE_MENU) {
1174                 handler_set_err(hdl, -EINVAL);
1175                 return NULL;
1176         }
1177         return v4l2_ctrl_new(hdl, ops, id, name, type,
1178                                     min, max, step, def, flags, NULL, NULL);
1179 }
1180 EXPORT_SYMBOL(v4l2_ctrl_new_std);
1181
1182 /* Helper function for standard menu controls */
1183 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
1184                         const struct v4l2_ctrl_ops *ops,
1185                         u32 id, s32 max, s32 mask, s32 def)
1186 {
1187         const char * const *qmenu = v4l2_ctrl_get_menu(id);
1188         const char *name;
1189         enum v4l2_ctrl_type type;
1190         s32 min;
1191         s32 step;
1192         u32 flags;
1193
1194         v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1195         if (type != V4L2_CTRL_TYPE_MENU) {
1196                 handler_set_err(hdl, -EINVAL);
1197                 return NULL;
1198         }
1199         return v4l2_ctrl_new(hdl, ops, id, name, type,
1200                                     0, max, mask, def, flags, qmenu, NULL);
1201 }
1202 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu);
1203
1204 /* Add a control from another handler to this handler */
1205 struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl,
1206                                           struct v4l2_ctrl *ctrl)
1207 {
1208         if (hdl == NULL || hdl->error)
1209                 return NULL;
1210         if (ctrl == NULL) {
1211                 handler_set_err(hdl, -EINVAL);
1212                 return NULL;
1213         }
1214         if (ctrl->handler == hdl)
1215                 return ctrl;
1216         return handler_new_ref(hdl, ctrl) ? NULL : ctrl;
1217 }
1218 EXPORT_SYMBOL(v4l2_ctrl_add_ctrl);
1219
1220 /* Add the controls from another handler to our own. */
1221 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
1222                           struct v4l2_ctrl_handler *add)
1223 {
1224         struct v4l2_ctrl *ctrl;
1225         int ret = 0;
1226
1227         /* Do nothing if either handler is NULL or if they are the same */
1228         if (!hdl || !add || hdl == add)
1229                 return 0;
1230         if (hdl->error)
1231                 return hdl->error;
1232         mutex_lock(&add->lock);
1233         list_for_each_entry(ctrl, &add->ctrls, node) {
1234                 /* Skip handler-private controls. */
1235                 if (ctrl->is_private)
1236                         continue;
1237                 /* And control classes */
1238                 if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1239                         continue;
1240                 ret = handler_new_ref(hdl, ctrl);
1241                 if (ret)
1242                         break;
1243         }
1244         mutex_unlock(&add->lock);
1245         return ret;
1246 }
1247 EXPORT_SYMBOL(v4l2_ctrl_add_handler);
1248
1249 /* Cluster controls */
1250 void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls)
1251 {
1252         int i;
1253
1254         /* The first control is the master control and it must not be NULL */
1255         BUG_ON(ncontrols == 0 || controls[0] == NULL);
1256
1257         for (i = 0; i < ncontrols; i++) {
1258                 if (controls[i]) {
1259                         controls[i]->cluster = controls;
1260                         controls[i]->ncontrols = ncontrols;
1261                 }
1262         }
1263 }
1264 EXPORT_SYMBOL(v4l2_ctrl_cluster);
1265
1266 void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls,
1267                             u8 manual_val, bool set_volatile)
1268 {
1269         struct v4l2_ctrl *master = controls[0];
1270         u32 flag;
1271         int i;
1272
1273         v4l2_ctrl_cluster(ncontrols, controls);
1274         WARN_ON(ncontrols <= 1);
1275         WARN_ON(manual_val < master->minimum || manual_val > master->maximum);
1276         master->is_auto = true;
1277         master->manual_mode_value = manual_val;
1278         master->flags |= V4L2_CTRL_FLAG_UPDATE;
1279         flag = is_cur_manual(master) ? 0 : V4L2_CTRL_FLAG_INACTIVE;
1280
1281         for (i = 1; i < ncontrols; i++)
1282                 if (controls[i]) {
1283                         controls[i]->is_volatile = set_volatile;
1284                         controls[i]->flags |= flag;
1285                 }
1286 }
1287 EXPORT_SYMBOL(v4l2_ctrl_auto_cluster);
1288
1289 /* Activate/deactivate a control. */
1290 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active)
1291 {
1292         /* invert since the actual flag is called 'inactive' */
1293         bool inactive = !active;
1294         bool old;
1295
1296         if (ctrl == NULL)
1297                 return;
1298
1299         if (inactive)
1300                 /* set V4L2_CTRL_FLAG_INACTIVE */
1301                 old = test_and_set_bit(4, &ctrl->flags);
1302         else
1303                 /* clear V4L2_CTRL_FLAG_INACTIVE */
1304                 old = test_and_clear_bit(4, &ctrl->flags);
1305         if (old != inactive)
1306                 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1307 }
1308 EXPORT_SYMBOL(v4l2_ctrl_activate);
1309
1310 /* Grab/ungrab a control.
1311    Typically used when streaming starts and you want to grab controls,
1312    preventing the user from changing them.
1313
1314    Just call this and the framework will block any attempts to change
1315    these controls. */
1316 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
1317 {
1318         bool old;
1319
1320         if (ctrl == NULL)
1321                 return;
1322
1323         v4l2_ctrl_lock(ctrl);
1324         if (grabbed)
1325                 /* set V4L2_CTRL_FLAG_GRABBED */
1326                 old = test_and_set_bit(1, &ctrl->flags);
1327         else
1328                 /* clear V4L2_CTRL_FLAG_GRABBED */
1329                 old = test_and_clear_bit(1, &ctrl->flags);
1330         if (old != grabbed)
1331                 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1332         v4l2_ctrl_unlock(ctrl);
1333 }
1334 EXPORT_SYMBOL(v4l2_ctrl_grab);
1335
1336 /* Log the control name and value */
1337 static void log_ctrl(const struct v4l2_ctrl *ctrl,
1338                      const char *prefix, const char *colon)
1339 {
1340         int fl_inact = ctrl->flags & V4L2_CTRL_FLAG_INACTIVE;
1341         int fl_grabbed = ctrl->flags & V4L2_CTRL_FLAG_GRABBED;
1342
1343         if (ctrl->flags & (V4L2_CTRL_FLAG_DISABLED | V4L2_CTRL_FLAG_WRITE_ONLY))
1344                 return;
1345         if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1346                 return;
1347
1348         printk(KERN_INFO "%s%s%s: ", prefix, colon, ctrl->name);
1349
1350         switch (ctrl->type) {
1351         case V4L2_CTRL_TYPE_INTEGER:
1352                 printk(KERN_CONT "%d", ctrl->cur.val);
1353                 break;
1354         case V4L2_CTRL_TYPE_BOOLEAN:
1355                 printk(KERN_CONT "%s", ctrl->cur.val ? "true" : "false");
1356                 break;
1357         case V4L2_CTRL_TYPE_MENU:
1358                 printk(KERN_CONT "%s", ctrl->qmenu[ctrl->cur.val]);
1359                 break;
1360         case V4L2_CTRL_TYPE_INTEGER64:
1361                 printk(KERN_CONT "%lld", ctrl->cur.val64);
1362                 break;
1363         case V4L2_CTRL_TYPE_STRING:
1364                 printk(KERN_CONT "%s", ctrl->cur.string);
1365                 break;
1366         default:
1367                 printk(KERN_CONT "unknown type %d", ctrl->type);
1368                 break;
1369         }
1370         if (fl_inact && fl_grabbed)
1371                 printk(KERN_CONT " (inactive, grabbed)\n");
1372         else if (fl_inact)
1373                 printk(KERN_CONT " (inactive)\n");
1374         else if (fl_grabbed)
1375                 printk(KERN_CONT " (grabbed)\n");
1376         else
1377                 printk(KERN_CONT "\n");
1378 }
1379
1380 /* Log all controls owned by the handler */
1381 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
1382                                   const char *prefix)
1383 {
1384         struct v4l2_ctrl *ctrl;
1385         const char *colon = "";
1386         int len;
1387
1388         if (hdl == NULL)
1389                 return;
1390         if (prefix == NULL)
1391                 prefix = "";
1392         len = strlen(prefix);
1393         if (len && prefix[len - 1] != ' ')
1394                 colon = ": ";
1395         mutex_lock(&hdl->lock);
1396         list_for_each_entry(ctrl, &hdl->ctrls, node)
1397                 if (!(ctrl->flags & V4L2_CTRL_FLAG_DISABLED))
1398                         log_ctrl(ctrl, prefix, colon);
1399         mutex_unlock(&hdl->lock);
1400 }
1401 EXPORT_SYMBOL(v4l2_ctrl_handler_log_status);
1402
1403 /* Call s_ctrl for all controls owned by the handler */
1404 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl)
1405 {
1406         struct v4l2_ctrl *ctrl;
1407         int ret = 0;
1408
1409         if (hdl == NULL)
1410                 return 0;
1411         mutex_lock(&hdl->lock);
1412         list_for_each_entry(ctrl, &hdl->ctrls, node)
1413                 ctrl->done = false;
1414
1415         list_for_each_entry(ctrl, &hdl->ctrls, node) {
1416                 struct v4l2_ctrl *master = ctrl->cluster[0];
1417                 int i;
1418
1419                 /* Skip if this control was already handled by a cluster. */
1420                 /* Skip button controls and read-only controls. */
1421                 if (ctrl->done || ctrl->type == V4L2_CTRL_TYPE_BUTTON ||
1422                     (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY))
1423                         continue;
1424
1425                 for (i = 0; i < master->ncontrols; i++) {
1426                         if (master->cluster[i]) {
1427                                 cur_to_new(master->cluster[i]);
1428                                 master->cluster[i]->is_new = 1;
1429                                 master->cluster[i]->done = true;
1430                         }
1431                 }
1432                 ret = call_op(master, s_ctrl);
1433                 if (ret)
1434                         break;
1435         }
1436         mutex_unlock(&hdl->lock);
1437         return ret;
1438 }
1439 EXPORT_SYMBOL(v4l2_ctrl_handler_setup);
1440
1441 /* Implement VIDIOC_QUERYCTRL */
1442 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc)
1443 {
1444         u32 id = qc->id & V4L2_CTRL_ID_MASK;
1445         struct v4l2_ctrl_ref *ref;
1446         struct v4l2_ctrl *ctrl;
1447
1448         if (hdl == NULL)
1449                 return -EINVAL;
1450
1451         mutex_lock(&hdl->lock);
1452
1453         /* Try to find it */
1454         ref = find_ref(hdl, id);
1455
1456         if ((qc->id & V4L2_CTRL_FLAG_NEXT_CTRL) && !list_empty(&hdl->ctrl_refs)) {
1457                 /* Find the next control with ID > qc->id */
1458
1459                 /* Did we reach the end of the control list? */
1460                 if (id >= node2id(hdl->ctrl_refs.prev)) {
1461                         ref = NULL; /* Yes, so there is no next control */
1462                 } else if (ref) {
1463                         /* We found a control with the given ID, so just get
1464                            the next one in the list. */
1465                         ref = list_entry(ref->node.next, typeof(*ref), node);
1466                 } else {
1467                         /* No control with the given ID exists, so start
1468                            searching for the next largest ID. We know there
1469                            is one, otherwise the first 'if' above would have
1470                            been true. */
1471                         list_for_each_entry(ref, &hdl->ctrl_refs, node)
1472                                 if (id < ref->ctrl->id)
1473                                         break;
1474                 }
1475         }
1476         mutex_unlock(&hdl->lock);
1477         if (!ref)
1478                 return -EINVAL;
1479
1480         ctrl = ref->ctrl;
1481         memset(qc, 0, sizeof(*qc));
1482         if (id >= V4L2_CID_PRIVATE_BASE)
1483                 qc->id = id;
1484         else
1485                 qc->id = ctrl->id;
1486         strlcpy(qc->name, ctrl->name, sizeof(qc->name));
1487         qc->minimum = ctrl->minimum;
1488         qc->maximum = ctrl->maximum;
1489         qc->default_value = ctrl->default_value;
1490         if (ctrl->type == V4L2_CTRL_TYPE_MENU)
1491                 qc->step = 1;
1492         else
1493                 qc->step = ctrl->step;
1494         qc->flags = ctrl->flags;
1495         qc->type = ctrl->type;
1496         return 0;
1497 }
1498 EXPORT_SYMBOL(v4l2_queryctrl);
1499
1500 int v4l2_subdev_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
1501 {
1502         if (qc->id & V4L2_CTRL_FLAG_NEXT_CTRL)
1503                 return -EINVAL;
1504         return v4l2_queryctrl(sd->ctrl_handler, qc);
1505 }
1506 EXPORT_SYMBOL(v4l2_subdev_queryctrl);
1507
1508 /* Implement VIDIOC_QUERYMENU */
1509 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm)
1510 {
1511         struct v4l2_ctrl *ctrl;
1512         u32 i = qm->index;
1513
1514         ctrl = v4l2_ctrl_find(hdl, qm->id);
1515         if (!ctrl)
1516                 return -EINVAL;
1517
1518         qm->reserved = 0;
1519         /* Sanity checks */
1520         if (ctrl->qmenu == NULL ||
1521             i < ctrl->minimum || i > ctrl->maximum)
1522                 return -EINVAL;
1523         /* Use mask to see if this menu item should be skipped */
1524         if (ctrl->menu_skip_mask & (1 << i))
1525                 return -EINVAL;
1526         /* Empty menu items should also be skipped */
1527         if (ctrl->qmenu[i] == NULL || ctrl->qmenu[i][0] == '\0')
1528                 return -EINVAL;
1529         strlcpy(qm->name, ctrl->qmenu[i], sizeof(qm->name));
1530         return 0;
1531 }
1532 EXPORT_SYMBOL(v4l2_querymenu);
1533
1534 int v4l2_subdev_querymenu(struct v4l2_subdev *sd, struct v4l2_querymenu *qm)
1535 {
1536         return v4l2_querymenu(sd->ctrl_handler, qm);
1537 }
1538 EXPORT_SYMBOL(v4l2_subdev_querymenu);
1539
1540
1541
1542 /* Some general notes on the atomic requirements of VIDIOC_G/TRY/S_EXT_CTRLS:
1543
1544    It is not a fully atomic operation, just best-effort only. After all, if
1545    multiple controls have to be set through multiple i2c writes (for example)
1546    then some initial writes may succeed while others fail. Thus leaving the
1547    system in an inconsistent state. The question is how much effort you are
1548    willing to spend on trying to make something atomic that really isn't.
1549
1550    From the point of view of an application the main requirement is that
1551    when you call VIDIOC_S_EXT_CTRLS and some values are invalid then an
1552    error should be returned without actually affecting any controls.
1553
1554    If all the values are correct, then it is acceptable to just give up
1555    in case of low-level errors.
1556
1557    It is important though that the application can tell when only a partial
1558    configuration was done. The way we do that is through the error_idx field
1559    of struct v4l2_ext_controls: if that is equal to the count field then no
1560    controls were affected. Otherwise all controls before that index were
1561    successful in performing their 'get' or 'set' operation, the control at
1562    the given index failed, and you don't know what happened with the controls
1563    after the failed one. Since if they were part of a control cluster they
1564    could have been successfully processed (if a cluster member was encountered
1565    at index < error_idx), they could have failed (if a cluster member was at
1566    error_idx), or they may not have been processed yet (if the first cluster
1567    member appeared after error_idx).
1568
1569    It is all fairly theoretical, though. In practice all you can do is to
1570    bail out. If error_idx == count, then it is an application bug. If
1571    error_idx < count then it is only an application bug if the error code was
1572    EBUSY. That usually means that something started streaming just when you
1573    tried to set the controls. In all other cases it is a driver/hardware
1574    problem and all you can do is to retry or bail out.
1575
1576    Note that these rules do not apply to VIDIOC_TRY_EXT_CTRLS: since that
1577    never modifies controls the error_idx is just set to whatever control
1578    has an invalid value.
1579  */
1580
1581 /* Prepare for the extended g/s/try functions.
1582    Find the controls in the control array and do some basic checks. */
1583 static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1584                              struct v4l2_ext_controls *cs,
1585                              struct v4l2_ctrl_helper *helpers)
1586 {
1587         struct v4l2_ctrl_helper *h;
1588         bool have_clusters = false;
1589         u32 i;
1590
1591         for (i = 0, h = helpers; i < cs->count; i++, h++) {
1592                 struct v4l2_ext_control *c = &cs->controls[i];
1593                 struct v4l2_ctrl_ref *ref;
1594                 struct v4l2_ctrl *ctrl;
1595                 u32 id = c->id & V4L2_CTRL_ID_MASK;
1596
1597                 cs->error_idx = i;
1598
1599                 if (cs->ctrl_class && V4L2_CTRL_ID2CLASS(id) != cs->ctrl_class)
1600                         return -EINVAL;
1601
1602                 /* Old-style private controls are not allowed for
1603                    extended controls */
1604                 if (id >= V4L2_CID_PRIVATE_BASE)
1605                         return -EINVAL;
1606                 ref = find_ref_lock(hdl, id);
1607                 if (ref == NULL)
1608                         return -EINVAL;
1609                 ctrl = ref->ctrl;
1610                 if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)
1611                         return -EINVAL;
1612
1613                 if (ctrl->cluster[0]->ncontrols > 1)
1614                         have_clusters = true;
1615                 if (ctrl->cluster[0] != ctrl)
1616                         ref = find_ref_lock(hdl, ctrl->cluster[0]->id);
1617                 /* Store the ref to the master control of the cluster */
1618                 h->mref = ref;
1619                 h->ctrl = ctrl;
1620                 /* Initially set next to 0, meaning that there is no other
1621                    control in this helper array belonging to the same
1622                    cluster */
1623                 h->next = 0;
1624         }
1625
1626         /* We are done if there were no controls that belong to a multi-
1627            control cluster. */
1628         if (!have_clusters)
1629                 return 0;
1630
1631         /* The code below figures out in O(n) time which controls in the list
1632            belong to the same cluster. */
1633
1634         /* This has to be done with the handler lock taken. */
1635         mutex_lock(&hdl->lock);
1636
1637         /* First zero the helper field in the master control references */
1638         for (i = 0; i < cs->count; i++)
1639                 helpers[i].mref->helper = 0;
1640         for (i = 0, h = helpers; i < cs->count; i++, h++) {
1641                 struct v4l2_ctrl_ref *mref = h->mref;
1642
1643                 /* If the mref->helper is set, then it points to an earlier
1644                    helper that belongs to the same cluster. */
1645                 if (mref->helper) {
1646                         /* Set the next field of mref->helper to the current
1647                            index: this means that that earlier helper now
1648                            points to the next helper in the same cluster. */
1649                         mref->helper->next = i;
1650                         /* mref should be set only for the first helper in the
1651                            cluster, clear the others. */
1652                         h->mref = NULL;
1653                 }
1654                 /* Point the mref helper to the current helper struct. */
1655                 mref->helper = h;
1656         }
1657         mutex_unlock(&hdl->lock);
1658         return 0;
1659 }
1660
1661 /* Handles the corner case where cs->count == 0. It checks whether the
1662    specified control class exists. If that class ID is 0, then it checks
1663    whether there are any controls at all. */
1664 static int class_check(struct v4l2_ctrl_handler *hdl, u32 ctrl_class)
1665 {
1666         if (ctrl_class == 0)
1667                 return list_empty(&hdl->ctrl_refs) ? -EINVAL : 0;
1668         return find_ref_lock(hdl, ctrl_class | 1) ? 0 : -EINVAL;
1669 }
1670
1671
1672
1673 /* Get extended controls. Allocates the helpers array if needed. */
1674 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1675 {
1676         struct v4l2_ctrl_helper helper[4];
1677         struct v4l2_ctrl_helper *helpers = helper;
1678         int ret;
1679         int i, j;
1680
1681         cs->error_idx = cs->count;
1682         cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1683
1684         if (hdl == NULL)
1685                 return -EINVAL;
1686
1687         if (cs->count == 0)
1688                 return class_check(hdl, cs->ctrl_class);
1689
1690         if (cs->count > ARRAY_SIZE(helper)) {
1691                 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1692                 if (helpers == NULL)
1693                         return -ENOMEM;
1694         }
1695
1696         ret = prepare_ext_ctrls(hdl, cs, helpers);
1697         cs->error_idx = cs->count;
1698
1699         for (i = 0; !ret && i < cs->count; i++)
1700                 if (helpers[i].ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1701                         ret = -EACCES;
1702
1703         for (i = 0; !ret && i < cs->count; i++) {
1704                 int (*ctrl_to_user)(struct v4l2_ext_control *c,
1705                                     struct v4l2_ctrl *ctrl) = cur_to_user;
1706                 struct v4l2_ctrl *master;
1707
1708                 if (helpers[i].mref == NULL)
1709                         continue;
1710
1711                 master = helpers[i].mref->ctrl;
1712                 cs->error_idx = i;
1713
1714                 v4l2_ctrl_lock(master);
1715
1716                 /* g_volatile_ctrl will update the new control values */
1717                 if (has_op(master, g_volatile_ctrl) && !is_cur_manual(master)) {
1718                         for (j = 0; j < master->ncontrols; j++)
1719                                 cur_to_new(master->cluster[j]);
1720                         ret = call_op(master, g_volatile_ctrl);
1721                         ctrl_to_user = new_to_user;
1722                 }
1723                 /* If OK, then copy the current (for non-volatile controls)
1724                    or the new (for volatile controls) control values to the
1725                    caller */
1726                 if (!ret) {
1727                         u32 idx = i;
1728
1729                         do {
1730                                 ret = ctrl_to_user(cs->controls + idx,
1731                                                    helpers[idx].ctrl);
1732                                 idx = helpers[idx].next;
1733                         } while (!ret && idx);
1734                 }
1735                 v4l2_ctrl_unlock(master);
1736         }
1737
1738         if (cs->count > ARRAY_SIZE(helper))
1739                 kfree(helpers);
1740         return ret;
1741 }
1742 EXPORT_SYMBOL(v4l2_g_ext_ctrls);
1743
1744 int v4l2_subdev_g_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1745 {
1746         return v4l2_g_ext_ctrls(sd->ctrl_handler, cs);
1747 }
1748 EXPORT_SYMBOL(v4l2_subdev_g_ext_ctrls);
1749
1750 /* Helper function to get a single control */
1751 static int get_ctrl(struct v4l2_ctrl *ctrl, s32 *val)
1752 {
1753         struct v4l2_ctrl *master = ctrl->cluster[0];
1754         int ret = 0;
1755         int i;
1756
1757         if (ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1758                 return -EACCES;
1759
1760         v4l2_ctrl_lock(master);
1761         /* g_volatile_ctrl will update the current control values */
1762         if (ctrl->is_volatile && !is_cur_manual(master)) {
1763                 for (i = 0; i < master->ncontrols; i++)
1764                         cur_to_new(master->cluster[i]);
1765                 ret = call_op(master, g_volatile_ctrl);
1766                 *val = ctrl->val;
1767         } else {
1768                 *val = ctrl->cur.val;
1769         }
1770         v4l2_ctrl_unlock(master);
1771         return ret;
1772 }
1773
1774 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *control)
1775 {
1776         struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
1777
1778         if (ctrl == NULL || !type_is_int(ctrl))
1779                 return -EINVAL;
1780         return get_ctrl(ctrl, &control->value);
1781 }
1782 EXPORT_SYMBOL(v4l2_g_ctrl);
1783
1784 int v4l2_subdev_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
1785 {
1786         return v4l2_g_ctrl(sd->ctrl_handler, control);
1787 }
1788 EXPORT_SYMBOL(v4l2_subdev_g_ctrl);
1789
1790 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl)
1791 {
1792         s32 val = 0;
1793
1794         /* It's a driver bug if this happens. */
1795         WARN_ON(!type_is_int(ctrl));
1796         get_ctrl(ctrl, &val);
1797         return val;
1798 }
1799 EXPORT_SYMBOL(v4l2_ctrl_g_ctrl);
1800
1801
1802 /* Core function that calls try/s_ctrl and ensures that the new value is
1803    copied to the current value on a set.
1804    Must be called with ctrl->handler->lock held. */
1805 static int try_or_set_cluster(struct v4l2_fh *fh,
1806                               struct v4l2_ctrl *master, bool set)
1807 {
1808         bool update_flag;
1809         int ret;
1810         int i;
1811
1812         /* Go through the cluster and either validate the new value or
1813            (if no new value was set), copy the current value to the new
1814            value, ensuring a consistent view for the control ops when
1815            called. */
1816         for (i = 0; i < master->ncontrols; i++) {
1817                 struct v4l2_ctrl *ctrl = master->cluster[i];
1818
1819                 if (ctrl == NULL)
1820                         continue;
1821
1822                 if (!ctrl->is_new) {
1823                         cur_to_new(ctrl);
1824                         continue;
1825                 }
1826                 /* Check again: it may have changed since the
1827                    previous check in try_or_set_ext_ctrls(). */
1828                 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1829                         return -EBUSY;
1830         }
1831
1832         ret = call_op(master, try_ctrl);
1833
1834         /* Don't set if there is no change */
1835         if (ret || !set || !cluster_changed(master))
1836                 return ret;
1837         ret = call_op(master, s_ctrl);
1838         if (ret)
1839                 return ret;
1840
1841         /* If OK, then make the new values permanent. */
1842         update_flag = is_cur_manual(master) != is_new_manual(master);
1843         for (i = 0; i < master->ncontrols; i++)
1844                 new_to_cur(fh, master->cluster[i], update_flag && i > 0);
1845         return 0;
1846 }
1847
1848 /* Validate controls. */
1849 static int validate_ctrls(struct v4l2_ext_controls *cs,
1850                           struct v4l2_ctrl_helper *helpers, bool set)
1851 {
1852         unsigned i;
1853         int ret = 0;
1854
1855         cs->error_idx = cs->count;
1856         for (i = 0; i < cs->count; i++) {
1857                 struct v4l2_ctrl *ctrl = helpers[i].ctrl;
1858
1859                 cs->error_idx = i;
1860
1861                 if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
1862                         return -EACCES;
1863                 /* This test is also done in try_set_control_cluster() which
1864                    is called in atomic context, so that has the final say,
1865                    but it makes sense to do an up-front check as well. Once
1866                    an error occurs in try_set_control_cluster() some other
1867                    controls may have been set already and we want to do a
1868                    best-effort to avoid that. */
1869                 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1870                         return -EBUSY;
1871                 ret = validate_new(ctrl, &cs->controls[i]);
1872                 if (ret)
1873                         return ret;
1874         }
1875         return 0;
1876 }
1877
1878 /* Try or try-and-set controls */
1879 static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1880                              struct v4l2_ext_controls *cs,
1881                              bool set)
1882 {
1883         struct v4l2_ctrl_helper helper[4];
1884         struct v4l2_ctrl_helper *helpers = helper;
1885         unsigned i, j;
1886         int ret;
1887
1888         cs->error_idx = cs->count;
1889         cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1890
1891         if (hdl == NULL)
1892                 return -EINVAL;
1893
1894         if (cs->count == 0)
1895                 return class_check(hdl, cs->ctrl_class);
1896
1897         if (cs->count > ARRAY_SIZE(helper)) {
1898                 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1899                 if (!helpers)
1900                         return -ENOMEM;
1901         }
1902         ret = prepare_ext_ctrls(hdl, cs, helpers);
1903         if (!ret)
1904                 ret = validate_ctrls(cs, helpers, set);
1905         if (ret && set)
1906                 cs->error_idx = cs->count;
1907         for (i = 0; !ret && i < cs->count; i++) {
1908                 struct v4l2_ctrl *master;
1909                 u32 idx = i;
1910
1911                 if (helpers[i].mref == NULL)
1912                         continue;
1913
1914                 cs->error_idx = i;
1915                 master = helpers[i].mref->ctrl;
1916                 v4l2_ctrl_lock(master);
1917
1918                 /* Reset the 'is_new' flags of the cluster */
1919                 for (j = 0; j < master->ncontrols; j++)
1920                         if (master->cluster[j])
1921                                 master->cluster[j]->is_new = 0;
1922
1923                 /* Copy the new caller-supplied control values.
1924                    user_to_new() sets 'is_new' to 1. */
1925                 do {
1926                         ret = user_to_new(cs->controls + idx, helpers[idx].ctrl);
1927                         idx = helpers[idx].next;
1928                 } while (!ret && idx);
1929
1930                 if (!ret)
1931                         ret = try_or_set_cluster(fh, master, set);
1932
1933                 /* Copy the new values back to userspace. */
1934                 if (!ret) {
1935                         idx = i;
1936                         do {
1937                                 ret = new_to_user(cs->controls + idx,
1938                                                 helpers[idx].ctrl);
1939                                 idx = helpers[idx].next;
1940                         } while (!ret && idx);
1941                 }
1942                 v4l2_ctrl_unlock(master);
1943         }
1944
1945         if (cs->count > ARRAY_SIZE(helper))
1946                 kfree(helpers);
1947         return ret;
1948 }
1949
1950 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1951 {
1952         return try_set_ext_ctrls(NULL, hdl, cs, false);
1953 }
1954 EXPORT_SYMBOL(v4l2_try_ext_ctrls);
1955
1956 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1957                                         struct v4l2_ext_controls *cs)
1958 {
1959         return try_set_ext_ctrls(fh, hdl, cs, true);
1960 }
1961 EXPORT_SYMBOL(v4l2_s_ext_ctrls);
1962
1963 int v4l2_subdev_try_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1964 {
1965         return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, false);
1966 }
1967 EXPORT_SYMBOL(v4l2_subdev_try_ext_ctrls);
1968
1969 int v4l2_subdev_s_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1970 {
1971         return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, true);
1972 }
1973 EXPORT_SYMBOL(v4l2_subdev_s_ext_ctrls);
1974
1975 /* Helper function for VIDIOC_S_CTRL compatibility */
1976 static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, s32 *val)
1977 {
1978         struct v4l2_ctrl *master = ctrl->cluster[0];
1979         int ret;
1980         int i;
1981
1982         ret = validate_new_int(ctrl, val);
1983         if (ret)
1984                 return ret;
1985
1986         v4l2_ctrl_lock(ctrl);
1987
1988         /* Reset the 'is_new' flags of the cluster */
1989         for (i = 0; i < master->ncontrols; i++)
1990                 if (master->cluster[i])
1991                         master->cluster[i]->is_new = 0;
1992
1993         ctrl->val = *val;
1994         ctrl->is_new = 1;
1995         ret = try_or_set_cluster(fh, master, true);
1996         *val = ctrl->cur.val;
1997         v4l2_ctrl_unlock(ctrl);
1998         return ret;
1999 }
2000
2001 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
2002                                         struct v4l2_control *control)
2003 {
2004         struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
2005
2006         if (ctrl == NULL || !type_is_int(ctrl))
2007                 return -EINVAL;
2008
2009         if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
2010                 return -EACCES;
2011
2012         return set_ctrl(fh, ctrl, &control->value);
2013 }
2014 EXPORT_SYMBOL(v4l2_s_ctrl);
2015
2016 int v4l2_subdev_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
2017 {
2018         return v4l2_s_ctrl(NULL, sd->ctrl_handler, control);
2019 }
2020 EXPORT_SYMBOL(v4l2_subdev_s_ctrl);
2021
2022 int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
2023 {
2024         /* It's a driver bug if this happens. */
2025         WARN_ON(!type_is_int(ctrl));
2026         return set_ctrl(NULL, ctrl, &val);
2027 }
2028 EXPORT_SYMBOL(v4l2_ctrl_s_ctrl);
2029
2030 void v4l2_ctrl_add_event(struct v4l2_ctrl *ctrl,
2031                                 struct v4l2_subscribed_event *sev)
2032 {
2033         v4l2_ctrl_lock(ctrl);
2034         list_add_tail(&sev->node, &ctrl->ev_subs);
2035         if (ctrl->type != V4L2_CTRL_TYPE_CTRL_CLASS &&
2036             (sev->flags & V4L2_EVENT_SUB_FL_SEND_INITIAL)) {
2037                 struct v4l2_event ev;
2038                 u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
2039
2040                 if (!(ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY))
2041                         changes |= V4L2_EVENT_CTRL_CH_VALUE;
2042                 fill_event(&ev, ctrl, changes);
2043                 v4l2_event_queue_fh(sev->fh, &ev);
2044         }
2045         v4l2_ctrl_unlock(ctrl);
2046 }
2047 EXPORT_SYMBOL(v4l2_ctrl_add_event);
2048
2049 void v4l2_ctrl_del_event(struct v4l2_ctrl *ctrl,
2050                                 struct v4l2_subscribed_event *sev)
2051 {
2052         v4l2_ctrl_lock(ctrl);
2053         list_del(&sev->node);
2054         v4l2_ctrl_unlock(ctrl);
2055 }
2056 EXPORT_SYMBOL(v4l2_ctrl_del_event);