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                         v4l2_event_queue_fh(sev->fh, &ev);
 595 }
 596
 597 /* Helper function: copy the current control value back to the caller */
 598 static int cur_to_user(struct v4l2_ext_control *c,
 599                        struct v4l2_ctrl *ctrl)
 600 {
 601         u32 len;
 602
 603         switch (ctrl->type) {
 604         case V4L2_CTRL_TYPE_STRING:
 605                 len = strlen(ctrl->cur.string);
 606                 if (c->size < len + 1) {
 607                         c->size = len + 1;
 608                         return -ENOSPC;
 609                 }
 610                 return copy_to_user(c->string, ctrl->cur.string,
 611                                                 len + 1) ? -EFAULT : 0;
 612         case V4L2_CTRL_TYPE_INTEGER64:
 613                 c->value64 = ctrl->cur.val64;
 614                 break;
 615         default:
 616                 c->value = ctrl->cur.val;
 617                 break;
 618         }
 619         return 0;
 620 }
 621
 622 /* Helper function: copy the caller-provider value as the new control value */
 623 static int user_to_new(struct v4l2_ext_control *c,
 624                        struct v4l2_ctrl *ctrl)
 625 {
 626         int ret;
 627         u32 size;
 628
 629         ctrl->is_new = 1;
 630         switch (ctrl->type) {
 631         case V4L2_CTRL_TYPE_INTEGER64:
 632                 ctrl->val64 = c->value64;
 633                 break;
 634         case V4L2_CTRL_TYPE_STRING:
 635                 size = c->size;
 636                 if (size == 0)
 637                         return -ERANGE;
 638                 if (size > ctrl->maximum + 1)
 639                         size = ctrl->maximum + 1;
 640                 ret = copy_from_user(ctrl->string, c->string, size);
 641                 if (!ret) {
 642                         char last = ctrl->string[size - 1];
 643
 644                         ctrl->string[size - 1] = 0;
 645                         /* If the string was longer than ctrl->maximum,
 646                            then return an error. */
 647                         if (strlen(ctrl->string) == ctrl->maximum && last)
 648                                 return -ERANGE;
 649                 }
 650                 return ret ? -EFAULT : 0;
 651         default:
 652                 ctrl->val = c->value;
 653                 break;
 654         }
 655         return 0;
 656 }
 657
 658 /* Helper function: copy the new control value back to the caller */
 659 static int new_to_user(struct v4l2_ext_control *c,
 660                        struct v4l2_ctrl *ctrl)
 661 {
 662         u32 len;
 663
 664         switch (ctrl->type) {
 665         case V4L2_CTRL_TYPE_STRING:
 666                 len = strlen(ctrl->string);
 667                 if (c->size < len + 1) {
 668                         c->size = ctrl->maximum + 1;
 669                         return -ENOSPC;
 670                 }
 671                 return copy_to_user(c->string, ctrl->string,
 672                                                 len + 1) ? -EFAULT : 0;
 673         case V4L2_CTRL_TYPE_INTEGER64:
 674                 c->value64 = ctrl->val64;
 675                 break;
 676         default:
 677                 c->value = ctrl->val;
 678                 break;
 679         }
 680         return 0;
 681 }
 682
 683 /* Copy the new value to the current value. */
 684 static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl,
 685                                                 bool update_inactive)
 686 {
 687         bool changed = false;
 688
 689         if (ctrl == NULL)
 690                 return;
 691         switch (ctrl->type) {
 692         case V4L2_CTRL_TYPE_BUTTON:
 693                 changed = true;
 694                 break;
 695         case V4L2_CTRL_TYPE_STRING:
 696                 /* strings are always 0-terminated */
 697                 changed = strcmp(ctrl->string, ctrl->cur.string);
 698                 strcpy(ctrl->cur.string, ctrl->string);
 699                 break;
 700         case V4L2_CTRL_TYPE_INTEGER64:
 701                 changed = ctrl->val64 != ctrl->cur.val64;
 702                 ctrl->cur.val64 = ctrl->val64;
 703                 break;
 704         default:
 705                 changed = ctrl->val != ctrl->cur.val;
 706                 ctrl->cur.val = ctrl->val;
 707                 break;
 708         }
 709         if (update_inactive) {
 710                 ctrl->flags &= ~V4L2_CTRL_FLAG_INACTIVE;
 711                 if (!is_cur_manual(ctrl->cluster[0]))
 712                         ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
 713         }
 714         if (changed || update_inactive)
 715                 send_event(fh, ctrl,
 716                         (changed ? V4L2_EVENT_CTRL_CH_VALUE : 0) |
 717                         (update_inactive ? V4L2_EVENT_CTRL_CH_FLAGS : 0));
 718 }
 719
 720 /* Copy the current value to the new value */
 721 static void cur_to_new(struct v4l2_ctrl *ctrl)
 722 {
 723         if (ctrl == NULL)
 724                 return;
 725         switch (ctrl->type) {
 726         case V4L2_CTRL_TYPE_STRING:
 727                 /* strings are always 0-terminated */
 728                 strcpy(ctrl->string, ctrl->cur.string);
 729                 break;
 730         case V4L2_CTRL_TYPE_INTEGER64:
 731                 ctrl->val64 = ctrl->cur.val64;
 732                 break;
 733         default:
 734                 ctrl->val = ctrl->cur.val;
 735                 break;
 736         }
 737 }
 738
 739 /* Return non-zero if one or more of the controls in the cluster has a new
 740    value that differs from the current value. */
 741 static int cluster_changed(struct v4l2_ctrl *master)
 742 {
 743         int diff = 0;
 744         int i;
 745
 746         for (i = 0; !diff && i < master->ncontrols; i++) {
 747                 struct v4l2_ctrl *ctrl = master->cluster[i];
 748
 749                 if (ctrl == NULL)
 750                         continue;
 751                 switch (ctrl->type) {
 752                 case V4L2_CTRL_TYPE_BUTTON:
 753                         /* Button controls are always 'different' */
 754                         return 1;
 755                 case V4L2_CTRL_TYPE_STRING:
 756                         /* strings are always 0-terminated */
 757                         diff = strcmp(ctrl->string, ctrl->cur.string);
 758                         break;
 759                 case V4L2_CTRL_TYPE_INTEGER64:
 760                         diff = ctrl->val64 != ctrl->cur.val64;
 761                         break;
 762                 default:
 763                         diff = ctrl->val != ctrl->cur.val;
 764                         break;
 765                 }
 766         }
 767         return diff;
 768 }
 769
 770 /* Validate integer-type control */
 771 static int validate_new_int(const struct v4l2_ctrl *ctrl, s32 *pval)
 772 {
 773         s32 val = *pval;
 774         u32 offset;
 775
 776         switch (ctrl->type) {
 777         case V4L2_CTRL_TYPE_INTEGER:
 778                 /* Round towards the closest legal value */
 779                 val += ctrl->step / 2;
 780                 if (val < ctrl->minimum)
 781                         val = ctrl->minimum;
 782                 if (val > ctrl->maximum)
 783                         val = ctrl->maximum;
 784                 offset = val - ctrl->minimum;
 785                 offset = ctrl->step * (offset / ctrl->step);
 786                 val = ctrl->minimum + offset;
 787                 *pval = val;
 788                 return 0;
 789
 790         case V4L2_CTRL_TYPE_BOOLEAN:
 791                 *pval = !!val;
 792                 return 0;
 793
 794         case V4L2_CTRL_TYPE_MENU:
 795                 if (val < ctrl->minimum || val > ctrl->maximum)
 796                         return -ERANGE;
 797                 if (ctrl->qmenu[val][0] == '\0' ||
 798                     (ctrl->menu_skip_mask & (1 << val)))
 799                         return -EINVAL;
 800                 return 0;
 801
 802         case V4L2_CTRL_TYPE_BUTTON:
 803         case V4L2_CTRL_TYPE_CTRL_CLASS:
 804                 *pval = 0;
 805                 return 0;
 806
 807         default:
 808                 return -EINVAL;
 809         }
 810 }
 811
 812 /* Validate a new control */
 813 static int validate_new(const struct v4l2_ctrl *ctrl, struct v4l2_ext_control *c)
 814 {
 815         char *s = c->string;
 816         size_t len;
 817
 818         switch (ctrl->type) {
 819         case V4L2_CTRL_TYPE_INTEGER:
 820         case V4L2_CTRL_TYPE_BOOLEAN:
 821         case V4L2_CTRL_TYPE_MENU:
 822         case V4L2_CTRL_TYPE_BUTTON:
 823         case V4L2_CTRL_TYPE_CTRL_CLASS:
 824                 return validate_new_int(ctrl, &c->value);
 825
 826         case V4L2_CTRL_TYPE_INTEGER64:
 827                 return 0;
 828
 829         case V4L2_CTRL_TYPE_STRING:
 830                 len = strlen(s);
 831                 if (len < ctrl->minimum)
 832                         return -ERANGE;
 833                 if ((len - ctrl->minimum) % ctrl->step)
 834                         return -ERANGE;
 835                 return 0;
 836
 837         default:
 838                 return -EINVAL;
 839         }
 840 }
 841
 842 static inline u32 node2id(struct list_head *node)
 843 {
 844         return list_entry(node, struct v4l2_ctrl_ref, node)->ctrl->id;
 845 }
 846
 847 /* Set the handler's error code if it wasn't set earlier already */
 848 static inline int handler_set_err(struct v4l2_ctrl_handler *hdl, int err)
 849 {
 850         if (hdl->error == 0)
 851                 hdl->error = err;
 852         return err;
 853 }
 854
 855 /* Initialize the handler */
 856 int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler *hdl,
 857                            unsigned nr_of_controls_hint)
 858 {
 859         mutex_init(&hdl->lock);
 860         INIT_LIST_HEAD(&hdl->ctrls);
 861         INIT_LIST_HEAD(&hdl->ctrl_refs);
 862         hdl->nr_of_buckets = 1 + nr_of_controls_hint / 8;
 863         hdl->buckets = kzalloc(sizeof(hdl->buckets[0]) * hdl->nr_of_buckets,
 864                                                                 GFP_KERNEL);
 865         hdl->error = hdl->buckets ? 0 : -ENOMEM;
 866         return hdl->error;
 867 }
 868 EXPORT_SYMBOL(v4l2_ctrl_handler_init);
 869
 870 /* Free all controls and control refs */
 871 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl)
 872 {
 873         struct v4l2_ctrl_ref *ref, *next_ref;
 874         struct v4l2_ctrl *ctrl, *next_ctrl;
 875         struct v4l2_subscribed_event *sev, *next_sev;
 876
 877         if (hdl == NULL || hdl->buckets == NULL)
 878                 return;
 879
 880         mutex_lock(&hdl->lock);
 881         /* Free all nodes */
 882         list_for_each_entry_safe(ref, next_ref, &hdl->ctrl_refs, node) {
 883                 list_del(&ref->node);
 884                 kfree(ref);
 885         }
 886         /* Free all controls owned by the handler */
 887         list_for_each_entry_safe(ctrl, next_ctrl, &hdl->ctrls, node) {
 888                 list_del(&ctrl->node);
 889                 list_for_each_entry_safe(sev, next_sev, &ctrl->ev_subs, node)
 890                         list_del(&sev->node);
 891                 kfree(ctrl);
 892         }
 893         kfree(hdl->buckets);
 894         hdl->buckets = NULL;
 895         hdl->cached = NULL;
 896         hdl->error = 0;
 897         mutex_unlock(&hdl->lock);
 898 }
 899 EXPORT_SYMBOL(v4l2_ctrl_handler_free);
 900
 901 /* For backwards compatibility: V4L2_CID_PRIVATE_BASE should no longer
 902    be used except in G_CTRL, S_CTRL, QUERYCTRL and QUERYMENU when dealing
 903    with applications that do not use the NEXT_CTRL flag.
 904
 905    We just find the n-th private user control. It's O(N), but that should not
 906    be an issue in this particular case. */
 907 static struct v4l2_ctrl_ref *find_private_ref(
 908                 struct v4l2_ctrl_handler *hdl, u32 id)
 909 {
 910         struct v4l2_ctrl_ref *ref;
 911
 912         id -= V4L2_CID_PRIVATE_BASE;
 913         list_for_each_entry(ref, &hdl->ctrl_refs, node) {
 914                 /* Search for private user controls that are compatible with
 915                    VIDIOC_G/S_CTRL. */
 916                 if (V4L2_CTRL_ID2CLASS(ref->ctrl->id) == V4L2_CTRL_CLASS_USER &&
 917                     V4L2_CTRL_DRIVER_PRIV(ref->ctrl->id)) {
 918                         if (!type_is_int(ref->ctrl))
 919                                 continue;
 920                         if (id == 0)
 921                                 return ref;
 922                         id--;
 923                 }
 924         }
 925         return NULL;
 926 }
 927
 928 /* Find a control with the given ID. */
 929 static struct v4l2_ctrl_ref *find_ref(struct v4l2_ctrl_handler *hdl, u32 id)
 930 {
 931         struct v4l2_ctrl_ref *ref;
 932         int bucket;
 933
 934         id &= V4L2_CTRL_ID_MASK;
 935
 936         /* Old-style private controls need special handling */
 937         if (id >= V4L2_CID_PRIVATE_BASE)
 938                 return find_private_ref(hdl, id);
 939         bucket = id % hdl->nr_of_buckets;
 940
 941         /* Simple optimization: cache the last control found */
 942         if (hdl->cached && hdl->cached->ctrl->id == id)
 943                 return hdl->cached;
 944
 945         /* Not in cache, search the hash */
 946         ref = hdl->buckets ? hdl->buckets[bucket] : NULL;
 947         while (ref && ref->ctrl->id != id)
 948                 ref = ref->next;
 949
 950         if (ref)
 951                 hdl->cached = ref; /* cache it! */
 952         return ref;
 953 }
 954
 955 /* Find a control with the given ID. Take the handler's lock first. */
 956 static struct v4l2_ctrl_ref *find_ref_lock(
 957                 struct v4l2_ctrl_handler *hdl, u32 id)
 958 {
 959         struct v4l2_ctrl_ref *ref = NULL;
 960
 961         if (hdl) {
 962                 mutex_lock(&hdl->lock);
 963                 ref = find_ref(hdl, id);
 964                 mutex_unlock(&hdl->lock);
 965         }
 966         return ref;
 967 }
 968
 969 /* Find a control with the given ID. */
 970 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id)
 971 {
 972         struct v4l2_ctrl_ref *ref = find_ref_lock(hdl, id);
 973
 974         return ref ? ref->ctrl : NULL;
 975 }
 976 EXPORT_SYMBOL(v4l2_ctrl_find);
 977
 978 /* Allocate a new v4l2_ctrl_ref and hook it into the handler. */
 979 static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
 980                            struct v4l2_ctrl *ctrl)
 981 {
 982         struct v4l2_ctrl_ref *ref;
 983         struct v4l2_ctrl_ref *new_ref;
 984         u32 id = ctrl->id;
 985         u32 class_ctrl = V4L2_CTRL_ID2CLASS(id) | 1;
 986         int bucket = id % hdl->nr_of_buckets;   /* which bucket to use */
 987
 988         /* Automatically add the control class if it is not yet present. */
 989         if (id != class_ctrl && find_ref_lock(hdl, class_ctrl) == NULL)
 990                 if (!v4l2_ctrl_new_std(hdl, NULL, class_ctrl, 0, 0, 0, 0))
 991                         return hdl->error;
 992
 993         if (hdl->error)
 994                 return hdl->error;
 995
 996         new_ref = kzalloc(sizeof(*new_ref), GFP_KERNEL);
 997         if (!new_ref)
 998                 return handler_set_err(hdl, -ENOMEM);
 999         new_ref->ctrl = ctrl;
1000         if (ctrl->handler == hdl) {
1001                 /* By default each control starts in a cluster of its own.
1002                    new_ref->ctrl is basically a cluster array with one
1003                    element, so that's perfect to use as the cluster pointer.
1004                    But only do this for the handler that owns the control. */
1005                 ctrl->cluster = &new_ref->ctrl;
1006                 ctrl->ncontrols = 1;
1007         }
1008
1009         INIT_LIST_HEAD(&new_ref->node);
1010
1011         mutex_lock(&hdl->lock);
1012
1013         /* Add immediately at the end of the list if the list is empty, or if
1014            the last element in the list has a lower ID.
1015            This ensures that when elements are added in ascending order the
1016            insertion is an O(1) operation. */
1017         if (list_empty(&hdl->ctrl_refs) || id > node2id(hdl->ctrl_refs.prev)) {
1018                 list_add_tail(&new_ref->node, &hdl->ctrl_refs);
1019                 goto insert_in_hash;
1020         }
1021
1022         /* Find insert position in sorted list */
1023         list_for_each_entry(ref, &hdl->ctrl_refs, node) {
1024                 if (ref->ctrl->id < id)
1025                         continue;
1026                 /* Don't add duplicates */
1027                 if (ref->ctrl->id == id) {
1028                         kfree(new_ref);
1029                         goto unlock;
1030                 }
1031                 list_add(&new_ref->node, ref->node.prev);
1032                 break;
1033         }
1034
1035 insert_in_hash:
1036         /* Insert the control node in the hash */
1037         new_ref->next = hdl->buckets[bucket];
1038         hdl->buckets[bucket] = new_ref;
1039
1040 unlock:
1041         mutex_unlock(&hdl->lock);
1042         return 0;
1043 }
1044
1045 /* Add a new control */
1046 static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
1047                         const struct v4l2_ctrl_ops *ops,
1048                         u32 id, const char *name, enum v4l2_ctrl_type type,
1049                         s32 min, s32 max, u32 step, s32 def,
1050                         u32 flags, const char * const *qmenu, void *priv)
1051 {
1052         struct v4l2_ctrl *ctrl;
1053         unsigned sz_extra = 0;
1054
1055         if (hdl->error)
1056                 return NULL;
1057
1058         /* Sanity checks */
1059         if (id == 0 || name == NULL || id >= V4L2_CID_PRIVATE_BASE ||
1060             max < min ||
1061             (type == V4L2_CTRL_TYPE_INTEGER && step == 0) ||
1062             (type == V4L2_CTRL_TYPE_MENU && qmenu == NULL) ||
1063             (type == V4L2_CTRL_TYPE_STRING && max == 0)) {
1064                 handler_set_err(hdl, -ERANGE);
1065                 return NULL;
1066         }
1067         if ((type == V4L2_CTRL_TYPE_INTEGER ||
1068              type == V4L2_CTRL_TYPE_MENU ||
1069              type == V4L2_CTRL_TYPE_BOOLEAN) &&
1070             (def < min || def > max)) {
1071                 handler_set_err(hdl, -ERANGE);
1072                 return NULL;
1073         }
1074
1075         if (type == V4L2_CTRL_TYPE_BUTTON)
1076                 flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
1077         else if (type == V4L2_CTRL_TYPE_CTRL_CLASS)
1078                 flags |= V4L2_CTRL_FLAG_READ_ONLY;
1079         else if (type == V4L2_CTRL_TYPE_STRING)
1080                 sz_extra += 2 * (max + 1);
1081
1082         ctrl = kzalloc(sizeof(*ctrl) + sz_extra, GFP_KERNEL);
1083         if (ctrl == NULL) {
1084                 handler_set_err(hdl, -ENOMEM);
1085                 return NULL;
1086         }
1087
1088         INIT_LIST_HEAD(&ctrl->node);
1089         INIT_LIST_HEAD(&ctrl->ev_subs);
1090         ctrl->handler = hdl;
1091         ctrl->ops = ops;
1092         ctrl->id = id;
1093         ctrl->name = name;
1094         ctrl->type = type;
1095         ctrl->flags = flags;
1096         ctrl->minimum = min;
1097         ctrl->maximum = max;
1098         ctrl->step = step;
1099         ctrl->qmenu = qmenu;
1100         ctrl->priv = priv;
1101         ctrl->cur.val = ctrl->val = ctrl->default_value = def;
1102
1103         if (ctrl->type == V4L2_CTRL_TYPE_STRING) {
1104                 ctrl->cur.string = (char *)&ctrl[1] + sz_extra - (max + 1);
1105                 ctrl->string = (char *)&ctrl[1] + sz_extra - 2 * (max + 1);
1106                 if (ctrl->minimum)
1107                         memset(ctrl->cur.string, ' ', ctrl->minimum);
1108         }
1109         if (handler_new_ref(hdl, ctrl)) {
1110                 kfree(ctrl);
1111                 return NULL;
1112         }
1113         mutex_lock(&hdl->lock);
1114         list_add_tail(&ctrl->node, &hdl->ctrls);
1115         mutex_unlock(&hdl->lock);
1116         return ctrl;
1117 }
1118
1119 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
1120                         const struct v4l2_ctrl_config *cfg, void *priv)
1121 {
1122         bool is_menu;
1123         struct v4l2_ctrl *ctrl;
1124         const char *name = cfg->name;
1125         const char * const *qmenu = cfg->qmenu;
1126         enum v4l2_ctrl_type type = cfg->type;
1127         u32 flags = cfg->flags;
1128         s32 min = cfg->min;
1129         s32 max = cfg->max;
1130         u32 step = cfg->step;
1131         s32 def = cfg->def;
1132
1133         if (name == NULL)
1134                 v4l2_ctrl_fill(cfg->id, &name, &type, &min, &max, &step,
1135                                                                 &def, &flags);
1136
1137         is_menu = (cfg->type == V4L2_CTRL_TYPE_MENU);
1138         if (is_menu)
1139                 WARN_ON(step);
1140         else
1141                 WARN_ON(cfg->menu_skip_mask);
1142         if (is_menu && qmenu == NULL)
1143                 qmenu = v4l2_ctrl_get_menu(cfg->id);
1144
1145         ctrl = v4l2_ctrl_new(hdl, cfg->ops, cfg->id, name,
1146                         type, min, max,
1147                         is_menu ? cfg->menu_skip_mask : step,
1148                         def, flags, qmenu, priv);
1149         if (ctrl) {
1150                 ctrl->is_private = cfg->is_private;
1151                 ctrl->is_volatile = cfg->is_volatile;
1152         }
1153         return ctrl;
1154 }
1155 EXPORT_SYMBOL(v4l2_ctrl_new_custom);
1156
1157 /* Helper function for standard non-menu controls */
1158 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
1159                         const struct v4l2_ctrl_ops *ops,
1160                         u32 id, s32 min, s32 max, u32 step, s32 def)
1161 {
1162         const char *name;
1163         enum v4l2_ctrl_type type;
1164         u32 flags;
1165
1166         v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1167         if (type == V4L2_CTRL_TYPE_MENU) {
1168                 handler_set_err(hdl, -EINVAL);
1169                 return NULL;
1170         }
1171         return v4l2_ctrl_new(hdl, ops, id, name, type,
1172                                     min, max, step, def, flags, NULL, NULL);
1173 }
1174 EXPORT_SYMBOL(v4l2_ctrl_new_std);
1175
1176 /* Helper function for standard menu controls */
1177 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
1178                         const struct v4l2_ctrl_ops *ops,
1179                         u32 id, s32 max, s32 mask, s32 def)
1180 {
1181         const char * const *qmenu = v4l2_ctrl_get_menu(id);
1182         const char *name;
1183         enum v4l2_ctrl_type type;
1184         s32 min;
1185         s32 step;
1186         u32 flags;
1187
1188         v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1189         if (type != V4L2_CTRL_TYPE_MENU) {
1190                 handler_set_err(hdl, -EINVAL);
1191                 return NULL;
1192         }
1193         return v4l2_ctrl_new(hdl, ops, id, name, type,
1194                                     0, max, mask, def, flags, qmenu, NULL);
1195 }
1196 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu);
1197
1198 /* Add a control from another handler to this handler */
1199 struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl,
1200                                           struct v4l2_ctrl *ctrl)
1201 {
1202         if (hdl == NULL || hdl->error)
1203                 return NULL;
1204         if (ctrl == NULL) {
1205                 handler_set_err(hdl, -EINVAL);
1206                 return NULL;
1207         }
1208         if (ctrl->handler == hdl)
1209                 return ctrl;
1210         return handler_new_ref(hdl, ctrl) ? NULL : ctrl;
1211 }
1212 EXPORT_SYMBOL(v4l2_ctrl_add_ctrl);
1213
1214 /* Add the controls from another handler to our own. */
1215 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
1216                           struct v4l2_ctrl_handler *add)
1217 {
1218         struct v4l2_ctrl *ctrl;
1219         int ret = 0;
1220
1221         /* Do nothing if either handler is NULL or if they are the same */
1222         if (!hdl || !add || hdl == add)
1223                 return 0;
1224         if (hdl->error)
1225                 return hdl->error;
1226         mutex_lock(&add->lock);
1227         list_for_each_entry(ctrl, &add->ctrls, node) {
1228                 /* Skip handler-private controls. */
1229                 if (ctrl->is_private)
1230                         continue;
1231                 /* And control classes */
1232                 if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1233                         continue;
1234                 ret = handler_new_ref(hdl, ctrl);
1235                 if (ret)
1236                         break;
1237         }
1238         mutex_unlock(&add->lock);
1239         return ret;
1240 }
1241 EXPORT_SYMBOL(v4l2_ctrl_add_handler);
1242
1243 /* Cluster controls */
1244 void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls)
1245 {
1246         int i;
1247
1248         /* The first control is the master control and it must not be NULL */
1249         BUG_ON(ncontrols == 0 || controls[0] == NULL);
1250
1251         for (i = 0; i < ncontrols; i++) {
1252                 if (controls[i]) {
1253                         controls[i]->cluster = controls;
1254                         controls[i]->ncontrols = ncontrols;
1255                 }
1256         }
1257 }
1258 EXPORT_SYMBOL(v4l2_ctrl_cluster);
1259
1260 void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls,
1261                             u8 manual_val, bool set_volatile)
1262 {
1263         struct v4l2_ctrl *master = controls[0];
1264         u32 flag;
1265         int i;
1266
1267         v4l2_ctrl_cluster(ncontrols, controls);
1268         WARN_ON(ncontrols <= 1);
1269         WARN_ON(manual_val < master->minimum || manual_val > master->maximum);
1270         master->is_auto = true;
1271         master->manual_mode_value = manual_val;
1272         master->flags |= V4L2_CTRL_FLAG_UPDATE;
1273         flag = is_cur_manual(master) ? 0 : V4L2_CTRL_FLAG_INACTIVE;
1274
1275         for (i = 1; i < ncontrols; i++)
1276                 if (controls[i]) {
1277                         controls[i]->is_volatile = set_volatile;
1278                         controls[i]->flags |= flag;
1279                 }
1280 }
1281 EXPORT_SYMBOL(v4l2_ctrl_auto_cluster);
1282
1283 /* Activate/deactivate a control. */
1284 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active)
1285 {
1286         /* invert since the actual flag is called 'inactive' */
1287         bool inactive = !active;
1288         bool old;
1289
1290         if (ctrl == NULL)
1291                 return;
1292
1293         if (inactive)
1294                 /* set V4L2_CTRL_FLAG_INACTIVE */
1295                 old = test_and_set_bit(4, &ctrl->flags);
1296         else
1297                 /* clear V4L2_CTRL_FLAG_INACTIVE */
1298                 old = test_and_clear_bit(4, &ctrl->flags);
1299         if (old != inactive)
1300                 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1301 }
1302 EXPORT_SYMBOL(v4l2_ctrl_activate);
1303
1304 /* Grab/ungrab a control.
1305    Typically used when streaming starts and you want to grab controls,
1306    preventing the user from changing them.
1307
1308    Just call this and the framework will block any attempts to change
1309    these controls. */
1310 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
1311 {
1312         bool old;
1313
1314         if (ctrl == NULL)
1315                 return;
1316
1317         v4l2_ctrl_lock(ctrl);
1318         if (grabbed)
1319                 /* set V4L2_CTRL_FLAG_GRABBED */
1320                 old = test_and_set_bit(1, &ctrl->flags);
1321         else
1322                 /* clear V4L2_CTRL_FLAG_GRABBED */
1323                 old = test_and_clear_bit(1, &ctrl->flags);
1324         if (old != grabbed)
1325                 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1326         v4l2_ctrl_unlock(ctrl);
1327 }
1328 EXPORT_SYMBOL(v4l2_ctrl_grab);
1329
1330 /* Log the control name and value */
1331 static void log_ctrl(const struct v4l2_ctrl *ctrl,
1332                      const char *prefix, const char *colon)
1333 {
1334         int fl_inact = ctrl->flags & V4L2_CTRL_FLAG_INACTIVE;
1335         int fl_grabbed = ctrl->flags & V4L2_CTRL_FLAG_GRABBED;
1336
1337         if (ctrl->flags & (V4L2_CTRL_FLAG_DISABLED | V4L2_CTRL_FLAG_WRITE_ONLY))
1338                 return;
1339         if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1340                 return;
1341
1342         printk(KERN_INFO "%s%s%s: ", prefix, colon, ctrl->name);
1343
1344         switch (ctrl->type) {
1345         case V4L2_CTRL_TYPE_INTEGER:
1346                 printk(KERN_CONT "%d", ctrl->cur.val);
1347                 break;
1348         case V4L2_CTRL_TYPE_BOOLEAN:
1349                 printk(KERN_CONT "%s", ctrl->cur.val ? "true" : "false");
1350                 break;
1351         case V4L2_CTRL_TYPE_MENU:
1352                 printk(KERN_CONT "%s", ctrl->qmenu[ctrl->cur.val]);
1353                 break;
1354         case V4L2_CTRL_TYPE_INTEGER64:
1355                 printk(KERN_CONT "%lld", ctrl->cur.val64);
1356                 break;
1357         case V4L2_CTRL_TYPE_STRING:
1358                 printk(KERN_CONT "%s", ctrl->cur.string);
1359                 break;
1360         default:
1361                 printk(KERN_CONT "unknown type %d", ctrl->type);
1362                 break;
1363         }
1364         if (fl_inact && fl_grabbed)
1365                 printk(KERN_CONT " (inactive, grabbed)\n");
1366         else if (fl_inact)
1367                 printk(KERN_CONT " (inactive)\n");
1368         else if (fl_grabbed)
1369                 printk(KERN_CONT " (grabbed)\n");
1370         else
1371                 printk(KERN_CONT "\n");
1372 }
1373
1374 /* Log all controls owned by the handler */
1375 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
1376                                   const char *prefix)
1377 {
1378         struct v4l2_ctrl *ctrl;
1379         const char *colon = "";
1380         int len;
1381
1382         if (hdl == NULL)
1383                 return;
1384         if (prefix == NULL)
1385                 prefix = "";
1386         len = strlen(prefix);
1387         if (len && prefix[len - 1] != ' ')
1388                 colon = ": ";
1389         mutex_lock(&hdl->lock);
1390         list_for_each_entry(ctrl, &hdl->ctrls, node)
1391                 if (!(ctrl->flags & V4L2_CTRL_FLAG_DISABLED))
1392                         log_ctrl(ctrl, prefix, colon);
1393         mutex_unlock(&hdl->lock);
1394 }
1395 EXPORT_SYMBOL(v4l2_ctrl_handler_log_status);
1396
1397 /* Call s_ctrl for all controls owned by the handler */
1398 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl)
1399 {
1400         struct v4l2_ctrl *ctrl;
1401         int ret = 0;
1402
1403         if (hdl == NULL)
1404                 return 0;
1405         mutex_lock(&hdl->lock);
1406         list_for_each_entry(ctrl, &hdl->ctrls, node)
1407                 ctrl->done = false;
1408
1409         list_for_each_entry(ctrl, &hdl->ctrls, node) {
1410                 struct v4l2_ctrl *master = ctrl->cluster[0];
1411                 int i;
1412
1413                 /* Skip if this control was already handled by a cluster. */
1414                 /* Skip button controls and read-only controls. */
1415                 if (ctrl->done || ctrl->type == V4L2_CTRL_TYPE_BUTTON ||
1416                     (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY))
1417                         continue;
1418
1419                 for (i = 0; i < master->ncontrols; i++) {
1420                         if (master->cluster[i]) {
1421                                 cur_to_new(master->cluster[i]);
1422                                 master->cluster[i]->is_new = 1;
1423                                 master->cluster[i]->done = true;
1424                         }
1425                 }
1426                 ret = call_op(master, s_ctrl);
1427                 if (ret)
1428                         break;
1429         }
1430         mutex_unlock(&hdl->lock);
1431         return ret;
1432 }
1433 EXPORT_SYMBOL(v4l2_ctrl_handler_setup);
1434
1435 /* Implement VIDIOC_QUERYCTRL */
1436 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc)
1437 {
1438         u32 id = qc->id & V4L2_CTRL_ID_MASK;
1439         struct v4l2_ctrl_ref *ref;
1440         struct v4l2_ctrl *ctrl;
1441
1442         if (hdl == NULL)
1443                 return -EINVAL;
1444
1445         mutex_lock(&hdl->lock);
1446
1447         /* Try to find it */
1448         ref = find_ref(hdl, id);
1449
1450         if ((qc->id & V4L2_CTRL_FLAG_NEXT_CTRL) && !list_empty(&hdl->ctrl_refs)) {
1451                 /* Find the next control with ID > qc->id */
1452
1453                 /* Did we reach the end of the control list? */
1454                 if (id >= node2id(hdl->ctrl_refs.prev)) {
1455                         ref = NULL; /* Yes, so there is no next control */
1456                 } else if (ref) {
1457                         /* We found a control with the given ID, so just get
1458                            the next one in the list. */
1459                         ref = list_entry(ref->node.next, typeof(*ref), node);
1460                 } else {
1461                         /* No control with the given ID exists, so start
1462                            searching for the next largest ID. We know there
1463                            is one, otherwise the first 'if' above would have
1464                            been true. */
1465                         list_for_each_entry(ref, &hdl->ctrl_refs, node)
1466                                 if (id < ref->ctrl->id)
1467                                         break;
1468                 }
1469         }
1470         mutex_unlock(&hdl->lock);
1471         if (!ref)
1472                 return -EINVAL;
1473
1474         ctrl = ref->ctrl;
1475         memset(qc, 0, sizeof(*qc));
1476         if (id >= V4L2_CID_PRIVATE_BASE)
1477                 qc->id = id;
1478         else
1479                 qc->id = ctrl->id;
1480         strlcpy(qc->name, ctrl->name, sizeof(qc->name));
1481         qc->minimum = ctrl->minimum;
1482         qc->maximum = ctrl->maximum;
1483         qc->default_value = ctrl->default_value;
1484         if (ctrl->type == V4L2_CTRL_TYPE_MENU)
1485                 qc->step = 1;
1486         else
1487                 qc->step = ctrl->step;
1488         qc->flags = ctrl->flags;
1489         qc->type = ctrl->type;
1490         return 0;
1491 }
1492 EXPORT_SYMBOL(v4l2_queryctrl);
1493
1494 int v4l2_subdev_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
1495 {
1496         if (qc->id & V4L2_CTRL_FLAG_NEXT_CTRL)
1497                 return -EINVAL;
1498         return v4l2_queryctrl(sd->ctrl_handler, qc);
1499 }
1500 EXPORT_SYMBOL(v4l2_subdev_queryctrl);
1501
1502 /* Implement VIDIOC_QUERYMENU */
1503 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm)
1504 {
1505         struct v4l2_ctrl *ctrl;
1506         u32 i = qm->index;
1507
1508         ctrl = v4l2_ctrl_find(hdl, qm->id);
1509         if (!ctrl)
1510                 return -EINVAL;
1511
1512         qm->reserved = 0;
1513         /* Sanity checks */
1514         if (ctrl->qmenu == NULL ||
1515             i < ctrl->minimum || i > ctrl->maximum)
1516                 return -EINVAL;
1517         /* Use mask to see if this menu item should be skipped */
1518         if (ctrl->menu_skip_mask & (1 << i))
1519                 return -EINVAL;
1520         /* Empty menu items should also be skipped */
1521         if (ctrl->qmenu[i] == NULL || ctrl->qmenu[i][0] == '\0')
1522                 return -EINVAL;
1523         strlcpy(qm->name, ctrl->qmenu[i], sizeof(qm->name));
1524         return 0;
1525 }
1526 EXPORT_SYMBOL(v4l2_querymenu);
1527
1528 int v4l2_subdev_querymenu(struct v4l2_subdev *sd, struct v4l2_querymenu *qm)
1529 {
1530         return v4l2_querymenu(sd->ctrl_handler, qm);
1531 }
1532 EXPORT_SYMBOL(v4l2_subdev_querymenu);
1533
1534
1535
1536 /* Some general notes on the atomic requirements of VIDIOC_G/TRY/S_EXT_CTRLS:
1537
1538    It is not a fully atomic operation, just best-effort only. After all, if
1539    multiple controls have to be set through multiple i2c writes (for example)
1540    then some initial writes may succeed while others fail. Thus leaving the
1541    system in an inconsistent state. The question is how much effort you are
1542    willing to spend on trying to make something atomic that really isn't.
1543
1544    From the point of view of an application the main requirement is that
1545    when you call VIDIOC_S_EXT_CTRLS and some values are invalid then an
1546    error should be returned without actually affecting any controls.
1547
1548    If all the values are correct, then it is acceptable to just give up
1549    in case of low-level errors.
1550
1551    It is important though that the application can tell when only a partial
1552    configuration was done. The way we do that is through the error_idx field
1553    of struct v4l2_ext_controls: if that is equal to the count field then no
1554    controls were affected. Otherwise all controls before that index were
1555    successful in performing their 'get' or 'set' operation, the control at
1556    the given index failed, and you don't know what happened with the controls
1557    after the failed one. Since if they were part of a control cluster they
1558    could have been successfully processed (if a cluster member was encountered
1559    at index < error_idx), they could have failed (if a cluster member was at
1560    error_idx), or they may not have been processed yet (if the first cluster
1561    member appeared after error_idx).
1562
1563    It is all fairly theoretical, though. In practice all you can do is to
1564    bail out. If error_idx == count, then it is an application bug. If
1565    error_idx < count then it is only an application bug if the error code was
1566    EBUSY. That usually means that something started streaming just when you
1567    tried to set the controls. In all other cases it is a driver/hardware
1568    problem and all you can do is to retry or bail out.
1569
1570    Note that these rules do not apply to VIDIOC_TRY_EXT_CTRLS: since that
1571    never modifies controls the error_idx is just set to whatever control
1572    has an invalid value.
1573  */
1574
1575 /* Prepare for the extended g/s/try functions.
1576    Find the controls in the control array and do some basic checks. */
1577 static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1578                              struct v4l2_ext_controls *cs,
1579                              struct v4l2_ctrl_helper *helpers)
1580 {
1581         struct v4l2_ctrl_helper *h;
1582         bool have_clusters = false;
1583         u32 i;
1584
1585         for (i = 0, h = helpers; i < cs->count; i++, h++) {
1586                 struct v4l2_ext_control *c = &cs->controls[i];
1587                 struct v4l2_ctrl_ref *ref;
1588                 struct v4l2_ctrl *ctrl;
1589                 u32 id = c->id & V4L2_CTRL_ID_MASK;
1590
1591                 cs->error_idx = i;
1592
1593                 if (cs->ctrl_class && V4L2_CTRL_ID2CLASS(id) != cs->ctrl_class)
1594                         return -EINVAL;
1595
1596                 /* Old-style private controls are not allowed for
1597                    extended controls */
1598                 if (id >= V4L2_CID_PRIVATE_BASE)
1599                         return -EINVAL;
1600                 ref = find_ref_lock(hdl, id);
1601                 if (ref == NULL)
1602                         return -EINVAL;
1603                 ctrl = ref->ctrl;
1604                 if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)
1605                         return -EINVAL;
1606
1607                 if (ctrl->cluster[0]->ncontrols > 1)
1608                         have_clusters = true;
1609                 if (ctrl->cluster[0] != ctrl)
1610                         ref = find_ref_lock(hdl, ctrl->cluster[0]->id);
1611                 /* Store the ref to the master control of the cluster */
1612                 h->mref = ref;
1613                 h->ctrl = ctrl;
1614                 /* Initially set next to 0, meaning that there is no other
1615                    control in this helper array belonging to the same
1616                    cluster */
1617                 h->next = 0;
1618         }
1619
1620         /* We are done if there were no controls that belong to a multi-
1621            control cluster. */
1622         if (!have_clusters)
1623                 return 0;
1624
1625         /* The code below figures out in O(n) time which controls in the list
1626            belong to the same cluster. */
1627
1628         /* This has to be done with the handler lock taken. */
1629         mutex_lock(&hdl->lock);
1630
1631         /* First zero the helper field in the master control references */
1632         for (i = 0; i < cs->count; i++)
1633                 helpers[i].mref->helper = 0;
1634         for (i = 0, h = helpers; i < cs->count; i++, h++) {
1635                 struct v4l2_ctrl_ref *mref = h->mref;
1636
1637                 /* If the mref->helper is set, then it points to an earlier
1638                    helper that belongs to the same cluster. */
1639                 if (mref->helper) {
1640                         /* Set the next field of mref->helper to the current
1641                            index: this means that that earlier helper now
1642                            points to the next helper in the same cluster. */
1643                         mref->helper->next = i;
1644                         /* mref should be set only for the first helper in the
1645                            cluster, clear the others. */
1646                         h->mref = NULL;
1647                 }
1648                 /* Point the mref helper to the current helper struct. */
1649                 mref->helper = h;
1650         }
1651         mutex_unlock(&hdl->lock);
1652         return 0;
1653 }
1654
1655 /* Handles the corner case where cs->count == 0. It checks whether the
1656    specified control class exists. If that class ID is 0, then it checks
1657    whether there are any controls at all. */
1658 static int class_check(struct v4l2_ctrl_handler *hdl, u32 ctrl_class)
1659 {
1660         if (ctrl_class == 0)
1661                 return list_empty(&hdl->ctrl_refs) ? -EINVAL : 0;
1662         return find_ref_lock(hdl, ctrl_class | 1) ? 0 : -EINVAL;
1663 }
1664
1665
1666
1667 /* Get extended controls. Allocates the helpers array if needed. */
1668 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1669 {
1670         struct v4l2_ctrl_helper helper[4];
1671         struct v4l2_ctrl_helper *helpers = helper;
1672         int ret;
1673         int i, j;
1674
1675         cs->error_idx = cs->count;
1676         cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1677
1678         if (hdl == NULL)
1679                 return -EINVAL;
1680
1681         if (cs->count == 0)
1682                 return class_check(hdl, cs->ctrl_class);
1683
1684         if (cs->count > ARRAY_SIZE(helper)) {
1685                 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1686                 if (helpers == NULL)
1687                         return -ENOMEM;
1688         }
1689
1690         ret = prepare_ext_ctrls(hdl, cs, helpers);
1691         cs->error_idx = cs->count;
1692
1693         for (i = 0; !ret && i < cs->count; i++)
1694                 if (helpers[i].ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1695                         ret = -EACCES;
1696
1697         for (i = 0; !ret && i < cs->count; i++) {
1698                 int (*ctrl_to_user)(struct v4l2_ext_control *c,
1699                                     struct v4l2_ctrl *ctrl) = cur_to_user;
1700                 struct v4l2_ctrl *master;
1701
1702                 if (helpers[i].mref == NULL)
1703                         continue;
1704
1705                 master = helpers[i].mref->ctrl;
1706                 cs->error_idx = i;
1707
1708                 v4l2_ctrl_lock(master);
1709
1710                 /* g_volatile_ctrl will update the new control values */
1711                 if (has_op(master, g_volatile_ctrl) && !is_cur_manual(master)) {
1712                         for (j = 0; j < master->ncontrols; j++)
1713                                 cur_to_new(master->cluster[j]);
1714                         ret = call_op(master, g_volatile_ctrl);
1715                         ctrl_to_user = new_to_user;
1716                 }
1717                 /* If OK, then copy the current (for non-volatile controls)
1718                    or the new (for volatile controls) control values to the
1719                    caller */
1720                 if (!ret) {
1721                         u32 idx = i;
1722
1723                         do {
1724                                 ret = ctrl_to_user(cs->controls + idx,
1725                                                    helpers[idx].ctrl);
1726                                 idx = helpers[idx].next;
1727                         } while (!ret && idx);
1728                 }
1729                 v4l2_ctrl_unlock(master);
1730         }
1731
1732         if (cs->count > ARRAY_SIZE(helper))
1733                 kfree(helpers);
1734         return ret;
1735 }
1736 EXPORT_SYMBOL(v4l2_g_ext_ctrls);
1737
1738 int v4l2_subdev_g_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1739 {
1740         return v4l2_g_ext_ctrls(sd->ctrl_handler, cs);
1741 }
1742 EXPORT_SYMBOL(v4l2_subdev_g_ext_ctrls);
1743
1744 /* Helper function to get a single control */
1745 static int get_ctrl(struct v4l2_ctrl *ctrl, s32 *val)
1746 {
1747         struct v4l2_ctrl *master = ctrl->cluster[0];
1748         int ret = 0;
1749         int i;
1750
1751         if (ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1752                 return -EACCES;
1753
1754         v4l2_ctrl_lock(master);
1755         /* g_volatile_ctrl will update the current control values */
1756         if (ctrl->is_volatile && !is_cur_manual(master)) {
1757                 for (i = 0; i < master->ncontrols; i++)
1758                         cur_to_new(master->cluster[i]);
1759                 ret = call_op(master, g_volatile_ctrl);
1760                 *val = ctrl->val;
1761         } else {
1762                 *val = ctrl->cur.val;
1763         }
1764         v4l2_ctrl_unlock(master);
1765         return ret;
1766 }
1767
1768 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *control)
1769 {
1770         struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
1771
1772         if (ctrl == NULL || !type_is_int(ctrl))
1773                 return -EINVAL;
1774         return get_ctrl(ctrl, &control->value);
1775 }
1776 EXPORT_SYMBOL(v4l2_g_ctrl);
1777
1778 int v4l2_subdev_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
1779 {
1780         return v4l2_g_ctrl(sd->ctrl_handler, control);
1781 }
1782 EXPORT_SYMBOL(v4l2_subdev_g_ctrl);
1783
1784 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl)
1785 {
1786         s32 val = 0;
1787
1788         /* It's a driver bug if this happens. */
1789         WARN_ON(!type_is_int(ctrl));
1790         get_ctrl(ctrl, &val);
1791         return val;
1792 }
1793 EXPORT_SYMBOL(v4l2_ctrl_g_ctrl);
1794
1795
1796 /* Core function that calls try/s_ctrl and ensures that the new value is
1797    copied to the current value on a set.
1798    Must be called with ctrl->handler->lock held. */
1799 static int try_or_set_cluster(struct v4l2_fh *fh,
1800                               struct v4l2_ctrl *master, bool set)
1801 {
1802         bool update_flag;
1803         int ret;
1804         int i;
1805
1806         /* Go through the cluster and either validate the new value or
1807            (if no new value was set), copy the current value to the new
1808            value, ensuring a consistent view for the control ops when
1809            called. */
1810         for (i = 0; i < master->ncontrols; i++) {
1811                 struct v4l2_ctrl *ctrl = master->cluster[i];
1812
1813                 if (ctrl == NULL)
1814                         continue;
1815
1816                 if (!ctrl->is_new) {
1817                         cur_to_new(ctrl);
1818                         continue;
1819                 }
1820                 /* Check again: it may have changed since the
1821                    previous check in try_or_set_ext_ctrls(). */
1822                 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1823                         return -EBUSY;
1824         }
1825
1826         ret = call_op(master, try_ctrl);
1827
1828         /* Don't set if there is no change */
1829         if (ret || !set || !cluster_changed(master))
1830                 return ret;
1831         ret = call_op(master, s_ctrl);
1832         if (ret)
1833                 return ret;
1834
1835         /* If OK, then make the new values permanent. */
1836         update_flag = is_cur_manual(master) != is_new_manual(master);
1837         for (i = 0; i < master->ncontrols; i++)
1838                 new_to_cur(fh, master->cluster[i], update_flag && i > 0);
1839         return 0;
1840 }
1841
1842 /* Validate controls. */
1843 static int validate_ctrls(struct v4l2_ext_controls *cs,
1844                           struct v4l2_ctrl_helper *helpers, bool set)
1845 {
1846         unsigned i;
1847         int ret = 0;
1848
1849         cs->error_idx = cs->count;
1850         for (i = 0; i < cs->count; i++) {
1851                 struct v4l2_ctrl *ctrl = helpers[i].ctrl;
1852
1853                 cs->error_idx = i;
1854
1855                 if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
1856                         return -EACCES;
1857                 /* This test is also done in try_set_control_cluster() which
1858                    is called in atomic context, so that has the final say,
1859                    but it makes sense to do an up-front check as well. Once
1860                    an error occurs in try_set_control_cluster() some other
1861                    controls may have been set already and we want to do a
1862                    best-effort to avoid that. */
1863                 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1864                         return -EBUSY;
1865                 ret = validate_new(ctrl, &cs->controls[i]);
1866                 if (ret)
1867                         return ret;
1868         }
1869         return 0;
1870 }
1871
1872 /* Try or try-and-set controls */
1873 static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1874                              struct v4l2_ext_controls *cs,
1875                              bool set)
1876 {
1877         struct v4l2_ctrl_helper helper[4];
1878         struct v4l2_ctrl_helper *helpers = helper;
1879         unsigned i, j;
1880         int ret;
1881
1882         cs->error_idx = cs->count;
1883         cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1884
1885         if (hdl == NULL)
1886                 return -EINVAL;
1887
1888         if (cs->count == 0)
1889                 return class_check(hdl, cs->ctrl_class);
1890
1891         if (cs->count > ARRAY_SIZE(helper)) {
1892                 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1893                 if (!helpers)
1894                         return -ENOMEM;
1895         }
1896         ret = prepare_ext_ctrls(hdl, cs, helpers);
1897         if (!ret)
1898                 ret = validate_ctrls(cs, helpers, set);
1899         if (ret && set)
1900                 cs->error_idx = cs->count;
1901         for (i = 0; !ret && i < cs->count; i++) {
1902                 struct v4l2_ctrl *master;
1903                 u32 idx = i;
1904
1905                 if (helpers[i].mref == NULL)
1906                         continue;
1907
1908                 cs->error_idx = i;
1909                 master = helpers[i].mref->ctrl;
1910                 v4l2_ctrl_lock(master);
1911
1912                 /* Reset the 'is_new' flags of the cluster */
1913                 for (j = 0; j < master->ncontrols; j++)
1914                         if (master->cluster[j])
1915                                 master->cluster[j]->is_new = 0;
1916
1917                 /* Copy the new caller-supplied control values.
1918                    user_to_new() sets 'is_new' to 1. */
1919                 do {
1920                         ret = user_to_new(cs->controls + idx, helpers[idx].ctrl);
1921                         idx = helpers[idx].next;
1922                 } while (!ret && idx);
1923
1924                 if (!ret)
1925                         ret = try_or_set_cluster(fh, master, set);
1926
1927                 /* Copy the new values back to userspace. */
1928                 if (!ret) {
1929                         idx = i;
1930                         do {
1931                                 ret = user_to_new(cs->controls + idx,
1932                                                 helpers[idx].ctrl);
1933                                 idx = helpers[idx].next;
1934                         } while (!ret && idx);
1935                 }
1936                 v4l2_ctrl_unlock(master);
1937         }
1938
1939         if (cs->count > ARRAY_SIZE(helper))
1940                 kfree(helpers);
1941         return ret;
1942 }
1943
1944 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1945 {
1946         return try_set_ext_ctrls(NULL, hdl, cs, false);
1947 }
1948 EXPORT_SYMBOL(v4l2_try_ext_ctrls);
1949
1950 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1951                                         struct v4l2_ext_controls *cs)
1952 {
1953         return try_set_ext_ctrls(fh, hdl, cs, true);
1954 }
1955 EXPORT_SYMBOL(v4l2_s_ext_ctrls);
1956
1957 int v4l2_subdev_try_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1958 {
1959         return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, false);
1960 }
1961 EXPORT_SYMBOL(v4l2_subdev_try_ext_ctrls);
1962
1963 int v4l2_subdev_s_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1964 {
1965         return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, true);
1966 }
1967 EXPORT_SYMBOL(v4l2_subdev_s_ext_ctrls);
1968
1969 /* Helper function for VIDIOC_S_CTRL compatibility */
1970 static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, s32 *val)
1971 {
1972         struct v4l2_ctrl *master = ctrl->cluster[0];
1973         int ret;
1974         int i;
1975
1976         ret = validate_new_int(ctrl, val);
1977         if (ret)
1978                 return ret;
1979
1980         v4l2_ctrl_lock(ctrl);
1981
1982         /* Reset the 'is_new' flags of the cluster */
1983         for (i = 0; i < master->ncontrols; i++)
1984                 if (master->cluster[i])
1985                         master->cluster[i]->is_new = 0;
1986
1987         ctrl->val = *val;
1988         ctrl->is_new = 1;
1989         ret = try_or_set_cluster(fh, master, true);
1990         *val = ctrl->cur.val;
1991         v4l2_ctrl_unlock(ctrl);
1992         return ret;
1993 }
1994
1995 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1996                                         struct v4l2_control *control)
1997 {
1998         struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
1999
2000         if (ctrl == NULL || !type_is_int(ctrl))
2001                 return -EINVAL;
2002
2003         if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
2004                 return -EACCES;
2005
2006         return set_ctrl(fh, ctrl, &control->value);
2007 }
2008 EXPORT_SYMBOL(v4l2_s_ctrl);
2009
2010 int v4l2_subdev_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
2011 {
2012         return v4l2_s_ctrl(NULL, sd->ctrl_handler, control);
2013 }
2014 EXPORT_SYMBOL(v4l2_subdev_s_ctrl);
2015
2016 int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
2017 {
2018         /* It's a driver bug if this happens. */
2019         WARN_ON(!type_is_int(ctrl));
2020         return set_ctrl(NULL, ctrl, &val);
2021 }
2022 EXPORT_SYMBOL(v4l2_ctrl_s_ctrl);
2023
2024 void v4l2_ctrl_add_event(struct v4l2_ctrl *ctrl,
2025                                 struct v4l2_subscribed_event *sev)
2026 {
2027         v4l2_ctrl_lock(ctrl);
2028         list_add_tail(&sev->node, &ctrl->ev_subs);
2029         if (ctrl->type != V4L2_CTRL_TYPE_CTRL_CLASS &&
2030             (sev->flags & V4L2_EVENT_SUB_FL_SEND_INITIAL)) {
2031                 struct v4l2_event ev;
2032                 u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
2033
2034                 if (!(ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY))
2035                         changes |= V4L2_EVENT_CTRL_CH_VALUE;
2036                 fill_event(&ev, ctrl, changes);
2037                 v4l2_event_queue_fh(sev->fh, &ev);
2038         }
2039         v4l2_ctrl_unlock(ctrl);
2040 }
2041 EXPORT_SYMBOL(v4l2_ctrl_add_event);
2042
2043 void v4l2_ctrl_del_event(struct v4l2_ctrl *ctrl,
2044                                 struct v4l2_subscribed_event *sev)
2045 {
2046         v4l2_ctrl_lock(ctrl);
2047         list_del(&sev->node);
2048         v4l2_ctrl_unlock(ctrl);
2049 }
2050 EXPORT_SYMBOL(v4l2_ctrl_del_event);