1 /* 2 V4L2 controls support header. 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 #ifndef _V4L2_CTRLS_H 22 #define _V4L2_CTRLS_H 23 24 #include <linux/list.h> 25 #include <linux/mutex.h> 26 #include <linux/videodev2.h> 27 28 /* forward references */ 29 struct file; 30 struct v4l2_ctrl_handler; 31 struct v4l2_ctrl_helper; 32 struct v4l2_ctrl; 33 struct video_device; 34 struct v4l2_subdev; 35 struct v4l2_subscribed_event; 36 struct v4l2_fh; 37 struct poll_table_struct; 38 39 /** 40 * union v4l2_ctrl_ptr - A pointer to a control value. 41 * @p_s32: Pointer to a 32-bit signed value. 42 * @p_s64: Pointer to a 64-bit signed value. 43 * @p_u8: Pointer to a 8-bit unsigned value. 44 * @p_u16: Pointer to a 16-bit unsigned value. 45 * @p_u32: Pointer to a 32-bit unsigned value. 46 * @p_char: Pointer to a string. 47 * @p: Pointer to a compound value. 48 */ 49 union v4l2_ctrl_ptr { 50 s32 *p_s32; 51 s64 *p_s64; 52 u8 *p_u8; 53 u16 *p_u16; 54 u32 *p_u32; 55 char *p_char; 56 void *p; 57 }; 58 59 /** 60 * struct v4l2_ctrl_ops - The control operations that the driver has to provide. 61 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant 62 * for volatile (and usually read-only) controls such as a control 63 * that returns the current signal strength which changes 64 * continuously. 65 * If not set, then the currently cached value will be returned. 66 * @try_ctrl: Test whether the control's value is valid. Only relevant when 67 * the usual min/max/step checks are not sufficient. 68 * @s_ctrl: Actually set the new control value. s_ctrl is compulsory. The 69 * ctrl->handler->lock is held when these ops are called, so no 70 * one else can access controls owned by that handler. 71 */ 72 struct v4l2_ctrl_ops { 73 int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl); 74 int (*try_ctrl)(struct v4l2_ctrl *ctrl); 75 int (*s_ctrl)(struct v4l2_ctrl *ctrl); 76 }; 77 78 /** 79 * struct v4l2_ctrl_type_ops - The control type operations that the driver 80 * has to provide. 81 * 82 * @equal: return true if both values are equal. 83 * @init: initialize the value. 84 * @log: log the value. 85 * @validate: validate the value. Return 0 on success and a negative value otherwise. 86 */ 87 struct v4l2_ctrl_type_ops { 88 bool (*equal)(const struct v4l2_ctrl *ctrl, u32 idx, 89 union v4l2_ctrl_ptr ptr1, 90 union v4l2_ctrl_ptr ptr2); 91 void (*init)(const struct v4l2_ctrl *ctrl, u32 idx, 92 union v4l2_ctrl_ptr ptr); 93 void (*log)(const struct v4l2_ctrl *ctrl); 94 int (*validate)(const struct v4l2_ctrl *ctrl, u32 idx, 95 union v4l2_ctrl_ptr ptr); 96 }; 97 98 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); 99 100 /** 101 * struct v4l2_ctrl - The control structure. 102 * @node: The list node. 103 * @ev_subs: The list of control event subscriptions. 104 * @handler: The handler that owns the control. 105 * @cluster: Point to start of cluster array. 106 * @ncontrols: Number of controls in cluster array. 107 * @done: Internal flag: set for each processed control. 108 * @is_new: Set when the user specified a new value for this control. It 109 * is also set when called from v4l2_ctrl_handler_setup. Drivers 110 * should never set this flag. 111 * @has_changed: Set when the current value differs from the new value. Drivers 112 * should never use this flag. 113 * @is_private: If set, then this control is private to its handler and it 114 * will not be added to any other handlers. Drivers can set 115 * this flag. 116 * @is_auto: If set, then this control selects whether the other cluster 117 * members are in 'automatic' mode or 'manual' mode. This is 118 * used for autogain/gain type clusters. Drivers should never 119 * set this flag directly. 120 * @is_int: If set, then this control has a simple integer value (i.e. it 121 * uses ctrl->val). 122 * @is_string: If set, then this control has type V4L2_CTRL_TYPE_STRING. 123 * @is_ptr: If set, then this control is an array and/or has type >= V4L2_CTRL_COMPOUND_TYPES 124 * and/or has type V4L2_CTRL_TYPE_STRING. In other words, struct 125 * v4l2_ext_control uses field p to point to the data. 126 * @is_array: If set, then this control contains an N-dimensional array. 127 * @has_volatiles: If set, then one or more members of the cluster are volatile. 128 * Drivers should never touch this flag. 129 * @call_notify: If set, then call the handler's notify function whenever the 130 * control's value changes. 131 * @manual_mode_value: If the is_auto flag is set, then this is the value 132 * of the auto control that determines if that control is in 133 * manual mode. So if the value of the auto control equals this 134 * value, then the whole cluster is in manual mode. Drivers should 135 * never set this flag directly. 136 * @ops: The control ops. 137 * @type_ops: The control type ops. 138 * @id: The control ID. 139 * @name: The control name. 140 * @type: The control type. 141 * @minimum: The control's minimum value. 142 * @maximum: The control's maximum value. 143 * @default_value: The control's default value. 144 * @step: The control's step value for non-menu controls. 145 * @elems: The number of elements in the N-dimensional array. 146 * @elem_size: The size in bytes of the control. 147 * @dims: The size of each dimension. 148 * @nr_of_dims:The number of dimensions in @dims. 149 * @menu_skip_mask: The control's skip mask for menu controls. This makes it 150 * easy to skip menu items that are not valid. If bit X is set, 151 * then menu item X is skipped. Of course, this only works for 152 * menus with <= 32 menu items. There are no menus that come 153 * close to that number, so this is OK. Should we ever need more, 154 * then this will have to be extended to a u64 or a bit array. 155 * @qmenu: A const char * array for all menu items. Array entries that are 156 * empty strings ("") correspond to non-existing menu items (this 157 * is in addition to the menu_skip_mask above). The last entry 158 * must be NULL. 159 * @flags: The control's flags. 160 * @cur: The control's current value. 161 * @val: The control's new s32 value. 162 * @priv: The control's private pointer. For use by the driver. It is 163 * untouched by the control framework. Note that this pointer is 164 * not freed when the control is deleted. Should this be needed 165 * then a new internal bitfield can be added to tell the framework 166 * to free this pointer. 167 * @p_cur: The control's current value represented via an union with 168 * provides a standard way of accessing control types 169 * through a pointer. 170 * @p_new: The control's new value represented via an union with provides 171 * a standard way of accessing control types 172 * through a pointer. 173 */ 174 struct v4l2_ctrl { 175 /* Administrative fields */ 176 struct list_head node; 177 struct list_head ev_subs; 178 struct v4l2_ctrl_handler *handler; 179 struct v4l2_ctrl **cluster; 180 unsigned ncontrols; 181 unsigned int done:1; 182 183 unsigned int is_new:1; 184 unsigned int has_changed:1; 185 unsigned int is_private:1; 186 unsigned int is_auto:1; 187 unsigned int is_int:1; 188 unsigned int is_string:1; 189 unsigned int is_ptr:1; 190 unsigned int is_array:1; 191 unsigned int has_volatiles:1; 192 unsigned int call_notify:1; 193 unsigned int manual_mode_value:8; 194 195 const struct v4l2_ctrl_ops *ops; 196 const struct v4l2_ctrl_type_ops *type_ops; 197 u32 id; 198 const char *name; 199 enum v4l2_ctrl_type type; 200 s64 minimum, maximum, default_value; 201 u32 elems; 202 u32 elem_size; 203 u32 dims[V4L2_CTRL_MAX_DIMS]; 204 u32 nr_of_dims; 205 union { 206 u64 step; 207 u64 menu_skip_mask; 208 }; 209 union { 210 const char * const *qmenu; 211 const s64 *qmenu_int; 212 }; 213 unsigned long flags; 214 void *priv; 215 s32 val; 216 struct { 217 s32 val; 218 } cur; 219 220 union v4l2_ctrl_ptr p_new; 221 union v4l2_ctrl_ptr p_cur; 222 }; 223 224 /** 225 * struct v4l2_ctrl_ref - The control reference. 226 * @node: List node for the sorted list. 227 * @next: Single-link list node for the hash. 228 * @ctrl: The actual control information. 229 * @helper: Pointer to helper struct. Used internally in prepare_ext_ctrls(). 230 * 231 * Each control handler has a list of these refs. The list_head is used to 232 * keep a sorted-by-control-ID list of all controls, while the next pointer 233 * is used to link the control in the hash's bucket. 234 */ 235 struct v4l2_ctrl_ref { 236 struct list_head node; 237 struct v4l2_ctrl_ref *next; 238 struct v4l2_ctrl *ctrl; 239 struct v4l2_ctrl_helper *helper; 240 }; 241 242 /** 243 * struct v4l2_ctrl_handler - The control handler keeps track of all the 244 * controls: both the controls owned by the handler and those inherited 245 * from other handlers. 246 * @_lock: Default for "lock". 247 * @lock: Lock to control access to this handler and its controls. 248 * May be replaced by the user right after init. 249 * @ctrls: The list of controls owned by this handler. 250 * @ctrl_refs: The list of control references. 251 * @cached: The last found control reference. It is common that the same 252 * control is needed multiple times, so this is a simple 253 * optimization. 254 * @buckets: Buckets for the hashing. Allows for quick control lookup. 255 * @notify: A notify callback that is called whenever the control changes value. 256 * Note that the handler's lock is held when the notify function 257 * is called! 258 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback. 259 * @nr_of_buckets: Total number of buckets in the array. 260 * @error: The error code of the first failed control addition. 261 */ 262 struct v4l2_ctrl_handler { 263 struct mutex _lock; 264 struct mutex *lock; 265 struct list_head ctrls; 266 struct list_head ctrl_refs; 267 struct v4l2_ctrl_ref *cached; 268 struct v4l2_ctrl_ref **buckets; 269 v4l2_ctrl_notify_fnc notify; 270 void *notify_priv; 271 u16 nr_of_buckets; 272 int error; 273 }; 274 275 /** 276 * struct v4l2_ctrl_config - Control configuration structure. 277 * @ops: The control ops. 278 * @type_ops: The control type ops. Only needed for compound controls. 279 * @id: The control ID. 280 * @name: The control name. 281 * @type: The control type. 282 * @min: The control's minimum value. 283 * @max: The control's maximum value. 284 * @step: The control's step value for non-menu controls. 285 * @def: The control's default value. 286 * @dims: The size of each dimension. 287 * @elem_size: The size in bytes of the control. 288 * @flags: The control's flags. 289 * @menu_skip_mask: The control's skip mask for menu controls. This makes it 290 * easy to skip menu items that are not valid. If bit X is set, 291 * then menu item X is skipped. Of course, this only works for 292 * menus with <= 64 menu items. There are no menus that come 293 * close to that number, so this is OK. Should we ever need more, 294 * then this will have to be extended to a bit array. 295 * @qmenu: A const char * array for all menu items. Array entries that are 296 * empty strings ("") correspond to non-existing menu items (this 297 * is in addition to the menu_skip_mask above). The last entry 298 * must be NULL. 299 * @qmenu_int: A const s64 integer array for all menu items of the type 300 * V4L2_CTRL_TYPE_INTEGER_MENU. 301 * @is_private: If set, then this control is private to its handler and it 302 * will not be added to any other handlers. 303 */ 304 struct v4l2_ctrl_config { 305 const struct v4l2_ctrl_ops *ops; 306 const struct v4l2_ctrl_type_ops *type_ops; 307 u32 id; 308 const char *name; 309 enum v4l2_ctrl_type type; 310 s64 min; 311 s64 max; 312 u64 step; 313 s64 def; 314 u32 dims[V4L2_CTRL_MAX_DIMS]; 315 u32 elem_size; 316 u32 flags; 317 u64 menu_skip_mask; 318 const char * const *qmenu; 319 const s64 *qmenu_int; 320 unsigned int is_private:1; 321 }; 322 323 /* 324 * v4l2_ctrl_fill() - Fill in the control fields based on the control ID. 325 * 326 * This works for all standard V4L2 controls. 327 * For non-standard controls it will only fill in the given arguments 328 * and @name will be NULL. 329 * 330 * This function will overwrite the contents of @name, @type and @flags. 331 * The contents of @min, @max, @step and @def may be modified depending on 332 * the type. 333 * 334 * Do not use in drivers! It is used internally for backwards compatibility 335 * control handling only. Once all drivers are converted to use the new 336 * control framework this function will no longer be exported. 337 */ 338 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, 339 s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags); 340 341 342 /** 343 * v4l2_ctrl_handler_init_class() - Initialize the control handler. 344 * @hdl: The control handler. 345 * @nr_of_controls_hint: A hint of how many controls this handler is 346 * expected to refer to. This is the total number, so including 347 * any inherited controls. It doesn't have to be precise, but if 348 * it is way off, then you either waste memory (too many buckets 349 * are allocated) or the control lookup becomes slower (not enough 350 * buckets are allocated, so there are more slow list lookups). 351 * It will always work, though. 352 * @key: Used by the lock validator if CONFIG_LOCKDEP is set. 353 * @name: Used by the lock validator if CONFIG_LOCKDEP is set. 354 * 355 * Returns an error if the buckets could not be allocated. This error will 356 * also be stored in @hdl->error. 357 * 358 * Never use this call directly, always use the v4l2_ctrl_handler_init 359 * macro that hides the @key and @name arguments. 360 */ 361 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl, 362 unsigned nr_of_controls_hint, 363 struct lock_class_key *key, const char *name); 364 365 #ifdef CONFIG_LOCKDEP 366 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 367 ( \ 368 ({ \ 369 static struct lock_class_key _key; \ 370 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \ 371 &_key, \ 372 KBUILD_BASENAME ":" \ 373 __stringify(__LINE__) ":" \ 374 "(" #hdl ")->_lock"); \ 375 }) \ 376 ) 377 #else 378 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 379 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL) 380 #endif 381 382 /** 383 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free 384 * the control list. 385 * @hdl: The control handler. 386 * 387 * Does nothing if @hdl == NULL. 388 */ 389 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl); 390 391 /** 392 * v4l2_ctrl_lock() - Helper function to lock the handler 393 * associated with the control. 394 * @ctrl: The control to lock. 395 */ 396 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) 397 { 398 mutex_lock(ctrl->handler->lock); 399 } 400 401 /** 402 * v4l2_ctrl_unlock() - Helper function to unlock the handler 403 * associated with the control. 404 * @ctrl: The control to unlock. 405 */ 406 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl) 407 { 408 mutex_unlock(ctrl->handler->lock); 409 } 410 411 /** 412 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging 413 * to the handler to initialize the hardware to the current control values. 414 * @hdl: The control handler. 415 * 416 * Button controls will be skipped, as are read-only controls. 417 * 418 * If @hdl == NULL, then this just returns 0. 419 */ 420 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl); 421 422 /** 423 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler. 424 * @hdl: The control handler. 425 * @prefix: The prefix to use when logging the control values. If the 426 * prefix does not end with a space, then ": " will be added 427 * after the prefix. If @prefix == NULL, then no prefix will be 428 * used. 429 * 430 * For use with VIDIOC_LOG_STATUS. 431 * 432 * Does nothing if @hdl == NULL. 433 */ 434 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, 435 const char *prefix); 436 437 /** 438 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2 439 * control. 440 * @hdl: The control handler. 441 * @cfg: The control's configuration data. 442 * @priv: The control's driver-specific private data. 443 * 444 * If the &v4l2_ctrl struct could not be allocated then NULL is returned 445 * and @hdl->error is set to the error code (if it wasn't set already). 446 */ 447 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, 448 const struct v4l2_ctrl_config *cfg, void *priv); 449 450 /** 451 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu control. 452 * @hdl: The control handler. 453 * @ops: The control ops. 454 * @id: The control ID. 455 * @min: The control's minimum value. 456 * @max: The control's maximum value. 457 * @step: The control's step value 458 * @def: The control's default value. 459 * 460 * If the &v4l2_ctrl struct could not be allocated, or the control 461 * ID is not known, then NULL is returned and @hdl->error is set to the 462 * appropriate error code (if it wasn't set already). 463 * 464 * If @id refers to a menu control, then this function will return NULL. 465 * 466 * Use v4l2_ctrl_new_std_menu() when adding menu controls. 467 */ 468 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, 469 const struct v4l2_ctrl_ops *ops, 470 u32 id, s64 min, s64 max, u64 step, s64 def); 471 472 /** 473 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 menu control. 474 * @hdl: The control handler. 475 * @ops: The control ops. 476 * @id: The control ID. 477 * @max: The control's maximum value. 478 * @mask: The control's skip mask for menu controls. This makes it 479 * easy to skip menu items that are not valid. If bit X is set, 480 * then menu item X is skipped. Of course, this only works for 481 * menus with <= 64 menu items. There are no menus that come 482 * close to that number, so this is OK. Should we ever need more, 483 * then this will have to be extended to a bit array. 484 * @def: The control's default value. 485 * 486 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value 487 * determines which menu items are to be skipped. 488 * 489 * If @id refers to a non-menu control, then this function will return NULL. 490 */ 491 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, 492 const struct v4l2_ctrl_ops *ops, 493 u32 id, u8 max, u64 mask, u8 def); 494 495 /** 496 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control 497 * with driver specific menu. 498 * @hdl: The control handler. 499 * @ops: The control ops. 500 * @id: The control ID. 501 * @max: The control's maximum value. 502 * @mask: The control's skip mask for menu controls. This makes it 503 * easy to skip menu items that are not valid. If bit X is set, 504 * then menu item X is skipped. Of course, this only works for 505 * menus with <= 64 menu items. There are no menus that come 506 * close to that number, so this is OK. Should we ever need more, 507 * then this will have to be extended to a bit array. 508 * @def: The control's default value. 509 * @qmenu: The new menu. 510 * 511 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific 512 * menu of this control. 513 * 514 */ 515 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, 516 const struct v4l2_ctrl_ops *ops, u32 id, u8 max, 517 u64 mask, u8 def, const char * const *qmenu); 518 519 /** 520 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control. 521 * @hdl: The control handler. 522 * @ops: The control ops. 523 * @id: The control ID. 524 * @max: The control's maximum value. 525 * @def: The control's default value. 526 * @qmenu_int: The control's menu entries. 527 * 528 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly 529 * takes as an argument an array of integers determining the menu items. 530 * 531 * If @id refers to a non-integer-menu control, then this function will return NULL. 532 */ 533 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl, 534 const struct v4l2_ctrl_ops *ops, 535 u32 id, u8 max, u8 def, const s64 *qmenu_int); 536 537 /** 538 * v4l2_ctrl_add_ctrl() - Add a control from another handler to this handler. 539 * @hdl: The control handler. 540 * @ctrl: The control to add. 541 * 542 * It will return NULL if it was unable to add the control reference. 543 * If the control already belonged to the handler, then it will do 544 * nothing and just return @ctrl. 545 */ 546 struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl, 547 struct v4l2_ctrl *ctrl); 548 549 /** 550 * v4l2_ctrl_add_handler() - Add all controls from handler @add to 551 * handler @hdl. 552 * @hdl: The control handler. 553 * @add: The control handler whose controls you want to add to 554 * the @hdl control handler. 555 * @filter: This function will filter which controls should be added. 556 * 557 * Does nothing if either of the two handlers is a NULL pointer. 558 * If @filter is NULL, then all controls are added. Otherwise only those 559 * controls for which @filter returns true will be added. 560 * In case of an error @hdl->error will be set to the error code (if it 561 * wasn't set already). 562 */ 563 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, 564 struct v4l2_ctrl_handler *add, 565 bool (*filter)(const struct v4l2_ctrl *ctrl)); 566 567 /** 568 * v4l2_ctrl_radio_filter() - Standard filter for radio controls. 569 * @ctrl: The control that is filtered. 570 * 571 * This will return true for any controls that are valid for radio device 572 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM 573 * transmitter class controls. 574 * 575 * This function is to be used with v4l2_ctrl_add_handler(). 576 */ 577 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl); 578 579 /** 580 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging to that cluster. 581 * @ncontrols: The number of controls in this cluster. 582 * @controls: The cluster control array of size @ncontrols. 583 */ 584 void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls); 585 586 587 /** 588 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging to 589 * that cluster and set it up for autofoo/foo-type handling. 590 * @ncontrols: The number of controls in this cluster. 591 * @controls: The cluster control array of size @ncontrols. The first control 592 * must be the 'auto' control (e.g. autogain, autoexposure, etc.) 593 * @manual_val: The value for the first control in the cluster that equals the 594 * manual setting. 595 * @set_volatile: If true, then all controls except the first auto control will 596 * be volatile. 597 * 598 * Use for control groups where one control selects some automatic feature and 599 * the other controls are only active whenever the automatic feature is turned 600 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs 601 * red and blue balance, etc. 602 * 603 * The behavior of such controls is as follows: 604 * 605 * When the autofoo control is set to automatic, then any manual controls 606 * are set to inactive and any reads will call g_volatile_ctrl (if the control 607 * was marked volatile). 608 * 609 * When the autofoo control is set to manual, then any manual controls will 610 * be marked active, and any reads will just return the current value without 611 * going through g_volatile_ctrl. 612 * 613 * In addition, this function will set the V4L2_CTRL_FLAG_UPDATE flag 614 * on the autofoo control and V4L2_CTRL_FLAG_INACTIVE on the foo control(s) 615 * if autofoo is in auto mode. 616 */ 617 void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls, 618 u8 manual_val, bool set_volatile); 619 620 621 /** 622 * v4l2_ctrl_find() - Find a control with the given ID. 623 * @hdl: The control handler. 624 * @id: The control ID to find. 625 * 626 * If @hdl == NULL this will return NULL as well. Will lock the handler so 627 * do not use from inside &v4l2_ctrl_ops. 628 */ 629 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id); 630 631 /** 632 * v4l2_ctrl_activate() - Make the control active or inactive. 633 * @ctrl: The control to (de)activate. 634 * @active: True if the control should become active. 635 * 636 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically. 637 * Does nothing if @ctrl == NULL. 638 * This will usually be called from within the s_ctrl op. 639 * The V4L2_EVENT_CTRL event will be generated afterwards. 640 * 641 * This function assumes that the control handler is locked. 642 */ 643 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); 644 645 /** 646 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed. 647 * @ctrl: The control to (de)activate. 648 * @grabbed: True if the control should become grabbed. 649 * 650 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically. 651 * Does nothing if @ctrl == NULL. 652 * The V4L2_EVENT_CTRL event will be generated afterwards. 653 * This will usually be called when starting or stopping streaming in the 654 * driver. 655 * 656 * This function assumes that the control handler is not locked and will 657 * take the lock itself. 658 */ 659 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); 660 661 662 /** 663 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range() 664 * 665 * @ctrl: The control to update. 666 * @min: The control's minimum value. 667 * @max: The control's maximum value. 668 * @step: The control's step value 669 * @def: The control's default value. 670 * 671 * Update the range of a control on the fly. This works for control types 672 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 673 * @step value is interpreted as a menu_skip_mask. 674 * 675 * An error is returned if one of the range arguments is invalid for this 676 * control type. 677 * 678 * This function assumes that the control handler is not locked and will 679 * take the lock itself. 680 */ 681 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 682 s64 min, s64 max, u64 step, s64 def); 683 684 /** 685 * v4l2_ctrl_modify_range() - Update the range of a control. 686 * @ctrl: The control to update. 687 * @min: The control's minimum value. 688 * @max: The control's maximum value. 689 * @step: The control's step value 690 * @def: The control's default value. 691 * 692 * Update the range of a control on the fly. This works for control types 693 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 694 * @step value is interpreted as a menu_skip_mask. 695 * 696 * An error is returned if one of the range arguments is invalid for this 697 * control type. 698 * 699 * This function assumes that the control handler is not locked and will 700 * take the lock itself. 701 */ 702 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 703 s64 min, s64 max, u64 step, s64 def) 704 { 705 int rval; 706 707 v4l2_ctrl_lock(ctrl); 708 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def); 709 v4l2_ctrl_unlock(ctrl); 710 711 return rval; 712 } 713 714 /** 715 * v4l2_ctrl_notify() - Function to set a notify callback for a control. 716 * @ctrl: The control. 717 * @notify: The callback function. 718 * @priv: The callback private handle, passed as argument to the callback. 719 * 720 * This function sets a callback function for the control. If @ctrl is NULL, 721 * then it will do nothing. If @notify is NULL, then the notify callback will 722 * be removed. 723 * 724 * There can be only one notify. If another already exists, then a WARN_ON 725 * will be issued and the function will do nothing. 726 */ 727 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, void *priv); 728 729 /** 730 * v4l2_ctrl_get_name() - Get the name of the control 731 * @id: The control ID. 732 * 733 * This function returns the name of the given control ID or NULL if it isn't 734 * a known control. 735 */ 736 const char *v4l2_ctrl_get_name(u32 id); 737 738 /** 739 * v4l2_ctrl_get_menu() - Get the menu string array of the control 740 * @id: The control ID. 741 * 742 * This function returns the NULL-terminated menu string array name of the 743 * given control ID or NULL if it isn't a known menu control. 744 */ 745 const char * const *v4l2_ctrl_get_menu(u32 id); 746 747 /** 748 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control 749 * @id: The control ID. 750 * @len: The size of the integer array. 751 * 752 * This function returns the integer array of the given control ID or NULL if it 753 * if it isn't a known integer menu control. 754 */ 755 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len); 756 757 /** 758 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from within a driver. 759 * @ctrl: The control. 760 * 761 * This returns the control's value safely by going through the control 762 * framework. This function will lock the control's handler, so it cannot be 763 * used from within the &v4l2_ctrl_ops functions. 764 * 765 * This function is for integer type controls only. 766 */ 767 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); 768 769 /** 770 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl(). 771 * @ctrl: The control. 772 * @val: The new value. 773 * 774 * This set the control's new value safely by going through the control 775 * framework. This function will lock the control's handler, so it cannot be 776 * used from within the &v4l2_ctrl_ops functions. 777 * 778 * This function is for integer type controls only. 779 */ 780 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val); 781 782 /** v4l2_ctrl_s_ctrl() - Helper function to set the control's value from within a driver. 783 * @ctrl: The control. 784 * @val: The new value. 785 * 786 * This set the control's new value safely by going through the control 787 * framework. This function will lock the control's handler, so it cannot be 788 * used from within the &v4l2_ctrl_ops functions. 789 * 790 * This function is for integer type controls only. 791 */ 792 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) 793 { 794 int rval; 795 796 v4l2_ctrl_lock(ctrl); 797 rval = __v4l2_ctrl_s_ctrl(ctrl, val); 798 v4l2_ctrl_unlock(ctrl); 799 800 return rval; 801 } 802 803 /** 804 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value 805 * from within a driver. 806 * @ctrl: The control. 807 * 808 * This returns the control's value safely by going through the control 809 * framework. This function will lock the control's handler, so it cannot be 810 * used from within the &v4l2_ctrl_ops functions. 811 * 812 * This function is for 64-bit integer type controls only. 813 */ 814 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl); 815 816 /** 817 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64(). 818 * 819 * @ctrl: The control. 820 * @val: The new value. 821 * 822 * This set the control's new value safely by going through the control 823 * framework. This function will lock the control's handler, so it cannot be 824 * used from within the &v4l2_ctrl_ops functions. 825 * 826 * This function is for 64-bit integer type controls only. 827 */ 828 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val); 829 830 /** v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value 831 * from within a driver. 832 * 833 * @ctrl: The control. 834 * @val: The new value. 835 * 836 * This set the control's new value safely by going through the control 837 * framework. This function will lock the control's handler, so it cannot be 838 * used from within the &v4l2_ctrl_ops functions. 839 * 840 * This function is for 64-bit integer type controls only. 841 */ 842 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) 843 { 844 int rval; 845 846 v4l2_ctrl_lock(ctrl); 847 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val); 848 v4l2_ctrl_unlock(ctrl); 849 850 return rval; 851 } 852 853 /** __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). 854 * 855 * @ctrl: The control. 856 * @s: The new string. 857 * 858 * This set the control's new string safely by going through the control 859 * framework. This function will lock the control's handler, so it cannot be 860 * used from within the &v4l2_ctrl_ops functions. 861 * 862 * This function is for string type controls only. 863 */ 864 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s); 865 866 /** v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value 867 * from within a driver. 868 * 869 * @ctrl: The control. 870 * @s: The new string. 871 * 872 * This set the control's new string safely by going through the control 873 * framework. This function will lock the control's handler, so it cannot be 874 * used from within the &v4l2_ctrl_ops functions. 875 * 876 * This function is for string type controls only. 877 */ 878 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s) 879 { 880 int rval; 881 882 v4l2_ctrl_lock(ctrl); 883 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s); 884 v4l2_ctrl_unlock(ctrl); 885 886 return rval; 887 } 888 889 /* Internal helper functions that deal with control events. */ 890 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops; 891 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new); 892 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new); 893 894 /* Can be used as a vidioc_log_status function that just dumps all controls 895 associated with the filehandle. */ 896 int v4l2_ctrl_log_status(struct file *file, void *fh); 897 898 /* Can be used as a vidioc_subscribe_event function that just subscribes 899 control events. */ 900 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, 901 const struct v4l2_event_subscription *sub); 902 903 /* Can be used as a poll function that just polls for control events. */ 904 unsigned int v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); 905 906 /* Helpers for ioctl_ops. If hdl == NULL then they will all return -EINVAL. */ 907 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc); 908 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_query_ext_ctrl *qc); 909 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm); 910 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl); 911 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 912 struct v4l2_control *ctrl); 913 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c); 914 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c); 915 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 916 struct v4l2_ext_controls *c); 917 918 /* Helpers for subdevices. If the associated ctrl_handler == NULL then they 919 will all return -EINVAL. */ 920 int v4l2_subdev_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc); 921 int v4l2_subdev_querymenu(struct v4l2_subdev *sd, struct v4l2_querymenu *qm); 922 int v4l2_subdev_g_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs); 923 int v4l2_subdev_try_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs); 924 int v4l2_subdev_s_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs); 925 int v4l2_subdev_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl); 926 int v4l2_subdev_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl); 927 928 /* Can be used as a subscribe_event function that just subscribes control 929 events. */ 930 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh, 931 struct v4l2_event_subscription *sub); 932 933 /* Log all controls owned by subdev's control handler. */ 934 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd); 935 936 #endif 937