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