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 17 #ifndef _V4L2_CTRLS_H 18 #define _V4L2_CTRLS_H 19 20 #include <linux/list.h> 21 #include <linux/mutex.h> 22 #include <linux/videodev2.h> 23 24 /* forward references */ 25 struct file; 26 struct v4l2_ctrl_handler; 27 struct v4l2_ctrl_helper; 28 struct v4l2_ctrl; 29 struct video_device; 30 struct v4l2_subdev; 31 struct v4l2_subscribed_event; 32 struct v4l2_fh; 33 struct poll_table_struct; 34 35 /** 36 * union v4l2_ctrl_ptr - A pointer to a control value. 37 * @p_s32: Pointer to a 32-bit signed value. 38 * @p_s64: Pointer to a 64-bit signed value. 39 * @p_u8: Pointer to a 8-bit unsigned value. 40 * @p_u16: Pointer to a 16-bit unsigned value. 41 * @p_u32: Pointer to a 32-bit unsigned value. 42 * @p_char: Pointer to a string. 43 * @p: Pointer to a compound value. 44 */ 45 union v4l2_ctrl_ptr { 46 s32 *p_s32; 47 s64 *p_s64; 48 u8 *p_u8; 49 u16 *p_u16; 50 u32 *p_u32; 51 char *p_char; 52 void *p; 53 }; 54 55 /** 56 * struct v4l2_ctrl_ops - The control operations that the driver has to provide. 57 * 58 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant 59 * for volatile (and usually read-only) controls such as a control 60 * that returns the current signal strength which changes 61 * continuously. 62 * If not set, then the currently cached value will be returned. 63 * @try_ctrl: Test whether the control's value is valid. Only relevant when 64 * the usual min/max/step checks are not sufficient. 65 * @s_ctrl: Actually set the new control value. s_ctrl is compulsory. The 66 * ctrl->handler->lock is held when these ops are called, so no 67 * one else can access controls owned by that handler. 68 */ 69 struct v4l2_ctrl_ops { 70 int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl); 71 int (*try_ctrl)(struct v4l2_ctrl *ctrl); 72 int (*s_ctrl)(struct v4l2_ctrl *ctrl); 73 }; 74 75 /** 76 * struct v4l2_ctrl_type_ops - The control type operations that the driver 77 * has to provide. 78 * 79 * @equal: return true if both values are equal. 80 * @init: initialize the value. 81 * @log: log the value. 82 * @validate: validate the value. Return 0 on success and a negative value 83 * otherwise. 84 */ 85 struct v4l2_ctrl_type_ops { 86 bool (*equal)(const struct v4l2_ctrl *ctrl, u32 idx, 87 union v4l2_ctrl_ptr ptr1, 88 union v4l2_ctrl_ptr ptr2); 89 void (*init)(const struct v4l2_ctrl *ctrl, u32 idx, 90 union v4l2_ctrl_ptr ptr); 91 void (*log)(const struct v4l2_ctrl *ctrl); 92 int (*validate)(const struct v4l2_ctrl *ctrl, u32 idx, 93 union v4l2_ctrl_ptr ptr); 94 }; 95 96 /** 97 * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function 98 * that should be called when a control value has changed. 99 * 100 * @ctrl: pointer to struct &v4l2_ctrl 101 * @priv: control private data 102 * 103 * This typedef definition is used as an argument to v4l2_ctrl_notify() 104 * and as an argument at struct &v4l2_ctrl_handler. 105 */ 106 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); 107 108 /** 109 * struct v4l2_ctrl - The control structure. 110 * 111 * @node: The list node. 112 * @ev_subs: The list of control event subscriptions. 113 * @handler: The handler that owns the control. 114 * @cluster: Point to start of cluster array. 115 * @ncontrols: Number of controls in cluster array. 116 * @done: Internal flag: set for each processed control. 117 * @is_new: Set when the user specified a new value for this control. It 118 * is also set when called from v4l2_ctrl_handler_setup(). Drivers 119 * should never set this flag. 120 * @has_changed: Set when the current value differs from the new value. Drivers 121 * should never use this flag. 122 * @is_private: If set, then this control is private to its handler and it 123 * will not be added to any other handlers. Drivers can set 124 * this flag. 125 * @is_auto: If set, then this control selects whether the other cluster 126 * members are in 'automatic' mode or 'manual' mode. This is 127 * used for autogain/gain type clusters. Drivers should never 128 * set this flag directly. 129 * @is_int: If set, then this control has a simple integer value (i.e. it 130 * uses ctrl->val). 131 * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING. 132 * @is_ptr: If set, then this control is an array and/or has type >= 133 * %V4L2_CTRL_COMPOUND_TYPES 134 * and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct 135 * v4l2_ext_control uses field p to point to the data. 136 * @is_array: If set, then this control contains an N-dimensional array. 137 * @has_volatiles: If set, then one or more members of the cluster are volatile. 138 * Drivers should never touch this flag. 139 * @call_notify: If set, then call the handler's notify function whenever the 140 * control's value changes. 141 * @manual_mode_value: If the is_auto flag is set, then this is the value 142 * of the auto control that determines if that control is in 143 * manual mode. So if the value of the auto control equals this 144 * value, then the whole cluster is in manual mode. Drivers should 145 * never set this flag directly. 146 * @ops: The control ops. 147 * @type_ops: The control type ops. 148 * @id: The control ID. 149 * @name: The control name. 150 * @type: The control type. 151 * @minimum: The control's minimum value. 152 * @maximum: The control's maximum value. 153 * @default_value: The control's default value. 154 * @step: The control's step value for non-menu controls. 155 * @elems: The number of elements in the N-dimensional array. 156 * @elem_size: The size in bytes of the control. 157 * @dims: The size of each dimension. 158 * @nr_of_dims:The number of dimensions in @dims. 159 * @menu_skip_mask: The control's skip mask for menu controls. This makes it 160 * easy to skip menu items that are not valid. If bit X is set, 161 * then menu item X is skipped. Of course, this only works for 162 * menus with <= 32 menu items. There are no menus that come 163 * close to that number, so this is OK. Should we ever need more, 164 * then this will have to be extended to a u64 or a bit array. 165 * @qmenu: A const char * array for all menu items. Array entries that are 166 * empty strings ("") correspond to non-existing menu items (this 167 * is in addition to the menu_skip_mask above). The last entry 168 * must be NULL. 169 * @flags: The control's flags. 170 * @cur: The control's current value. 171 * @val: The control's new s32 value. 172 * @priv: The control's private pointer. For use by the driver. It is 173 * untouched by the control framework. Note that this pointer is 174 * not freed when the control is deleted. Should this be needed 175 * then a new internal bitfield can be added to tell the framework 176 * to free this pointer. 177 * @p_cur: The control's current value represented via an union with 178 * provides a standard way of accessing control types 179 * through a pointer. 180 * @p_new: The control's new value represented via an union with provides 181 * a standard way of accessing control types 182 * through a pointer. 183 */ 184 struct v4l2_ctrl { 185 /* Administrative fields */ 186 struct list_head node; 187 struct list_head ev_subs; 188 struct v4l2_ctrl_handler *handler; 189 struct v4l2_ctrl **cluster; 190 unsigned int ncontrols; 191 192 unsigned int done:1; 193 194 unsigned int is_new:1; 195 unsigned int has_changed:1; 196 unsigned int is_private:1; 197 unsigned int is_auto:1; 198 unsigned int is_int:1; 199 unsigned int is_string:1; 200 unsigned int is_ptr:1; 201 unsigned int is_array:1; 202 unsigned int has_volatiles:1; 203 unsigned int call_notify:1; 204 unsigned int manual_mode_value:8; 205 206 const struct v4l2_ctrl_ops *ops; 207 const struct v4l2_ctrl_type_ops *type_ops; 208 u32 id; 209 const char *name; 210 enum v4l2_ctrl_type type; 211 s64 minimum, maximum, default_value; 212 u32 elems; 213 u32 elem_size; 214 u32 dims[V4L2_CTRL_MAX_DIMS]; 215 u32 nr_of_dims; 216 union { 217 u64 step; 218 u64 menu_skip_mask; 219 }; 220 union { 221 const char * const *qmenu; 222 const s64 *qmenu_int; 223 }; 224 unsigned long flags; 225 void *priv; 226 s32 val; 227 struct { 228 s32 val; 229 } cur; 230 231 union v4l2_ctrl_ptr p_new; 232 union v4l2_ctrl_ptr p_cur; 233 }; 234 235 /** 236 * struct v4l2_ctrl_ref - The control reference. 237 * 238 * @node: List node for the sorted list. 239 * @next: Single-link list node for the hash. 240 * @ctrl: The actual control information. 241 * @helper: Pointer to helper struct. Used internally in 242 * ``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``. 243 * 244 * Each control handler has a list of these refs. The list_head is used to 245 * keep a sorted-by-control-ID list of all controls, while the next pointer 246 * is used to link the control in the hash's bucket. 247 */ 248 struct v4l2_ctrl_ref { 249 struct list_head node; 250 struct v4l2_ctrl_ref *next; 251 struct v4l2_ctrl *ctrl; 252 struct v4l2_ctrl_helper *helper; 253 }; 254 255 /** 256 * struct v4l2_ctrl_handler - The control handler keeps track of all the 257 * controls: both the controls owned by the handler and those inherited 258 * from other handlers. 259 * 260 * @_lock: Default for "lock". 261 * @lock: Lock to control access to this handler and its controls. 262 * May be replaced by the user right after init. 263 * @ctrls: The list of controls owned by this handler. 264 * @ctrl_refs: The list of control references. 265 * @cached: The last found control reference. It is common that the same 266 * control is needed multiple times, so this is a simple 267 * optimization. 268 * @buckets: Buckets for the hashing. Allows for quick control lookup. 269 * @notify: A notify callback that is called whenever the control changes 270 * value. 271 * Note that the handler's lock is held when the notify function 272 * is called! 273 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback. 274 * @nr_of_buckets: Total number of buckets in the array. 275 * @error: The error code of the first failed control addition. 276 */ 277 struct v4l2_ctrl_handler { 278 struct mutex _lock; 279 struct mutex *lock; 280 struct list_head ctrls; 281 struct list_head ctrl_refs; 282 struct v4l2_ctrl_ref *cached; 283 struct v4l2_ctrl_ref **buckets; 284 v4l2_ctrl_notify_fnc notify; 285 void *notify_priv; 286 u16 nr_of_buckets; 287 int error; 288 }; 289 290 /** 291 * struct v4l2_ctrl_config - Control configuration structure. 292 * 293 * @ops: The control ops. 294 * @type_ops: The control type ops. Only needed for compound controls. 295 * @id: The control ID. 296 * @name: The control name. 297 * @type: The control type. 298 * @min: The control's minimum value. 299 * @max: The control's maximum value. 300 * @step: The control's step value for non-menu controls. 301 * @def: The control's default value. 302 * @dims: The size of each dimension. 303 * @elem_size: The size in bytes of the control. 304 * @flags: The control's flags. 305 * @menu_skip_mask: The control's skip mask for menu controls. This makes it 306 * easy to skip menu items that are not valid. If bit X is set, 307 * then menu item X is skipped. Of course, this only works for 308 * menus with <= 64 menu items. There are no menus that come 309 * close to that number, so this is OK. Should we ever need more, 310 * then this will have to be extended to a bit array. 311 * @qmenu: A const char * array for all menu items. Array entries that are 312 * empty strings ("") correspond to non-existing menu items (this 313 * is in addition to the menu_skip_mask above). The last entry 314 * must be NULL. 315 * @qmenu_int: A const s64 integer array for all menu items of the type 316 * V4L2_CTRL_TYPE_INTEGER_MENU. 317 * @is_private: If set, then this control is private to its handler and it 318 * will not be added to any other handlers. 319 */ 320 struct v4l2_ctrl_config { 321 const struct v4l2_ctrl_ops *ops; 322 const struct v4l2_ctrl_type_ops *type_ops; 323 u32 id; 324 const char *name; 325 enum v4l2_ctrl_type type; 326 s64 min; 327 s64 max; 328 u64 step; 329 s64 def; 330 u32 dims[V4L2_CTRL_MAX_DIMS]; 331 u32 elem_size; 332 u32 flags; 333 u64 menu_skip_mask; 334 const char * const *qmenu; 335 const s64 *qmenu_int; 336 unsigned int is_private:1; 337 }; 338 339 /** 340 * v4l2_ctrl_fill - Fill in the control fields based on the control ID. 341 * 342 * @id: ID of the control 343 * @name: name of the control 344 * @type: type of the control 345 * @min: minimum value for the control 346 * @max: maximum value for the control 347 * @step: control step 348 * @def: default value for the control 349 * @flags: flags to be used on the control 350 * 351 * This works for all standard V4L2 controls. 352 * For non-standard controls it will only fill in the given arguments 353 * and @name will be %NULL. 354 * 355 * This function will overwrite the contents of @name, @type and @flags. 356 * The contents of @min, @max, @step and @def may be modified depending on 357 * the type. 358 * 359 * .. note:: 360 * 361 * Do not use in drivers! It is used internally for backwards compatibility 362 * control handling only. Once all drivers are converted to use the new 363 * control framework this function will no longer be exported. 364 */ 365 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, 366 s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags); 367 368 369 /** 370 * v4l2_ctrl_handler_init_class() - Initialize the control handler. 371 * @hdl: The control handler. 372 * @nr_of_controls_hint: A hint of how many controls this handler is 373 * expected to refer to. This is the total number, so including 374 * any inherited controls. It doesn't have to be precise, but if 375 * it is way off, then you either waste memory (too many buckets 376 * are allocated) or the control lookup becomes slower (not enough 377 * buckets are allocated, so there are more slow list lookups). 378 * It will always work, though. 379 * @key: Used by the lock validator if CONFIG_LOCKDEP is set. 380 * @name: Used by the lock validator if CONFIG_LOCKDEP is set. 381 * 382 * .. attention:: 383 * 384 * Never use this call directly, always use the v4l2_ctrl_handler_init() 385 * macro that hides the @key and @name arguments. 386 * 387 * Return: returns an error if the buckets could not be allocated. This 388 * error will also be stored in @hdl->error. 389 */ 390 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl, 391 unsigned int nr_of_controls_hint, 392 struct lock_class_key *key, const char *name); 393 394 #ifdef CONFIG_LOCKDEP 395 396 /** 397 * v4l2_ctrl_handler_init - 398 * 399 * @hdl: The control handler. 400 * @nr_of_controls_hint: A hint of how many controls this handler is 401 * expected to refer to. This is the total number, so including 402 * any inherited controls. It doesn't have to be precise, but if 403 * it is way off, then you either waste memory (too many buckets 404 * are allocated) or the control lookup becomes slower (not enough 405 * buckets are allocated, so there are more slow list lookups). 406 * It will always work, though. 407 * 408 * This helper function creates a static struct &lock_class_key and 409 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock 410 * validador. 411 * 412 * Use this helper function to initialize a control handler. 413 */ 414 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 415 ( \ 416 ({ \ 417 static struct lock_class_key _key; \ 418 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \ 419 &_key, \ 420 KBUILD_BASENAME ":" \ 421 __stringify(__LINE__) ":" \ 422 "(" #hdl ")->_lock"); \ 423 }) \ 424 ) 425 #else 426 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 427 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL) 428 #endif 429 430 /** 431 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free 432 * the control list. 433 * @hdl: The control handler. 434 * 435 * Does nothing if @hdl == NULL. 436 */ 437 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl); 438 439 /** 440 * v4l2_ctrl_lock() - Helper function to lock the handler 441 * associated with the control. 442 * @ctrl: The control to lock. 443 */ 444 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) 445 { 446 mutex_lock(ctrl->handler->lock); 447 } 448 449 /** 450 * v4l2_ctrl_unlock() - Helper function to unlock the handler 451 * associated with the control. 452 * @ctrl: The control to unlock. 453 */ 454 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl) 455 { 456 mutex_unlock(ctrl->handler->lock); 457 } 458 459 /** 460 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging 461 * to the handler to initialize the hardware to the current control values. 462 * @hdl: The control handler. 463 * 464 * Button controls will be skipped, as are read-only controls. 465 * 466 * If @hdl == NULL, then this just returns 0. 467 */ 468 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl); 469 470 /** 471 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler. 472 * @hdl: The control handler. 473 * @prefix: The prefix to use when logging the control values. If the 474 * prefix does not end with a space, then ": " will be added 475 * after the prefix. If @prefix == NULL, then no prefix will be 476 * used. 477 * 478 * For use with VIDIOC_LOG_STATUS. 479 * 480 * Does nothing if @hdl == NULL. 481 */ 482 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, 483 const char *prefix); 484 485 /** 486 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2 487 * control. 488 * 489 * @hdl: The control handler. 490 * @cfg: The control's configuration data. 491 * @priv: The control's driver-specific private data. 492 * 493 * If the &v4l2_ctrl struct could not be allocated then NULL is returned 494 * and @hdl->error is set to the error code (if it wasn't set already). 495 */ 496 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, 497 const struct v4l2_ctrl_config *cfg, 498 void *priv); 499 500 /** 501 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu 502 * control. 503 * 504 * @hdl: The control handler. 505 * @ops: The control ops. 506 * @id: The control ID. 507 * @min: The control's minimum value. 508 * @max: The control's maximum value. 509 * @step: The control's step value 510 * @def: The control's default value. 511 * 512 * If the &v4l2_ctrl struct could not be allocated, or the control 513 * ID is not known, then NULL is returned and @hdl->error is set to the 514 * appropriate error code (if it wasn't set already). 515 * 516 * If @id refers to a menu control, then this function will return NULL. 517 * 518 * Use v4l2_ctrl_new_std_menu() when adding menu controls. 519 */ 520 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, 521 const struct v4l2_ctrl_ops *ops, 522 u32 id, s64 min, s64 max, u64 step, 523 s64 def); 524 525 /** 526 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 527 * menu control. 528 * 529 * @hdl: The control handler. 530 * @ops: The control ops. 531 * @id: The control ID. 532 * @max: The control's maximum value. 533 * @mask: The control's skip mask for menu controls. This makes it 534 * easy to skip menu items that are not valid. If bit X is set, 535 * then menu item X is skipped. Of course, this only works for 536 * menus with <= 64 menu items. There are no menus that come 537 * close to that number, so this is OK. Should we ever need more, 538 * then this will have to be extended to a bit array. 539 * @def: The control's default value. 540 * 541 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value 542 * determines which menu items are to be skipped. 543 * 544 * If @id refers to a non-menu control, then this function will return NULL. 545 */ 546 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, 547 const struct v4l2_ctrl_ops *ops, 548 u32 id, u8 max, u64 mask, u8 def); 549 550 /** 551 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control 552 * with driver specific menu. 553 * 554 * @hdl: The control handler. 555 * @ops: The control ops. 556 * @id: The control ID. 557 * @max: The control's maximum value. 558 * @mask: The control's skip mask for menu controls. This makes it 559 * easy to skip menu items that are not valid. If bit X is set, 560 * then menu item X is skipped. Of course, this only works for 561 * menus with <= 64 menu items. There are no menus that come 562 * close to that number, so this is OK. Should we ever need more, 563 * then this will have to be extended to a bit array. 564 * @def: The control's default value. 565 * @qmenu: The new menu. 566 * 567 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific 568 * menu of this control. 569 * 570 */ 571 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, 572 const struct v4l2_ctrl_ops *ops, 573 u32 id, u8 max, 574 u64 mask, u8 def, 575 const char * const *qmenu); 576 577 /** 578 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control. 579 * 580 * @hdl: The control handler. 581 * @ops: The control ops. 582 * @id: The control ID. 583 * @max: The control's maximum value. 584 * @def: The control's default value. 585 * @qmenu_int: The control's menu entries. 586 * 587 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly 588 * takes as an argument an array of integers determining the menu items. 589 * 590 * If @id refers to a non-integer-menu control, then this function will 591 * return %NULL. 592 */ 593 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl, 594 const struct v4l2_ctrl_ops *ops, 595 u32 id, u8 max, u8 def, 596 const s64 *qmenu_int); 597 598 /** 599 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be 600 * used when adding a control handler. 601 * 602 * @ctrl: pointer to struct &v4l2_ctrl. 603 */ 604 605 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl); 606 607 /** 608 * v4l2_ctrl_add_handler() - Add all controls from handler @add to 609 * handler @hdl. 610 * 611 * @hdl: The control handler. 612 * @add: The control handler whose controls you want to add to 613 * the @hdl control handler. 614 * @filter: This function will filter which controls should be added. 615 * 616 * Does nothing if either of the two handlers is a NULL pointer. 617 * If @filter is NULL, then all controls are added. Otherwise only those 618 * controls for which @filter returns true will be added. 619 * In case of an error @hdl->error will be set to the error code (if it 620 * wasn't set already). 621 */ 622 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, 623 struct v4l2_ctrl_handler *add, 624 v4l2_ctrl_filter filter); 625 626 /** 627 * v4l2_ctrl_radio_filter() - Standard filter for radio controls. 628 * 629 * @ctrl: The control that is filtered. 630 * 631 * This will return true for any controls that are valid for radio device 632 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM 633 * transmitter class controls. 634 * 635 * This function is to be used with v4l2_ctrl_add_handler(). 636 */ 637 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl); 638 639 /** 640 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging 641 * to that cluster. 642 * 643 * @ncontrols: The number of controls in this cluster. 644 * @controls: The cluster control array of size @ncontrols. 645 */ 646 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls); 647 648 649 /** 650 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging 651 * to that cluster and set it up for autofoo/foo-type handling. 652 * 653 * @ncontrols: The number of controls in this cluster. 654 * @controls: The cluster control array of size @ncontrols. The first control 655 * must be the 'auto' control (e.g. autogain, autoexposure, etc.) 656 * @manual_val: The value for the first control in the cluster that equals the 657 * manual setting. 658 * @set_volatile: If true, then all controls except the first auto control will 659 * be volatile. 660 * 661 * Use for control groups where one control selects some automatic feature and 662 * the other controls are only active whenever the automatic feature is turned 663 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs 664 * red and blue balance, etc. 665 * 666 * The behavior of such controls is as follows: 667 * 668 * When the autofoo control is set to automatic, then any manual controls 669 * are set to inactive and any reads will call g_volatile_ctrl (if the control 670 * was marked volatile). 671 * 672 * When the autofoo control is set to manual, then any manual controls will 673 * be marked active, and any reads will just return the current value without 674 * going through g_volatile_ctrl. 675 * 676 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag 677 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s) 678 * if autofoo is in auto mode. 679 */ 680 void v4l2_ctrl_auto_cluster(unsigned int ncontrols, 681 struct v4l2_ctrl **controls, 682 u8 manual_val, bool set_volatile); 683 684 685 /** 686 * v4l2_ctrl_find() - Find a control with the given ID. 687 * 688 * @hdl: The control handler. 689 * @id: The control ID to find. 690 * 691 * If @hdl == NULL this will return NULL as well. Will lock the handler so 692 * do not use from inside &v4l2_ctrl_ops. 693 */ 694 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id); 695 696 /** 697 * v4l2_ctrl_activate() - Make the control active or inactive. 698 * @ctrl: The control to (de)activate. 699 * @active: True if the control should become active. 700 * 701 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically. 702 * Does nothing if @ctrl == NULL. 703 * This will usually be called from within the s_ctrl op. 704 * The V4L2_EVENT_CTRL event will be generated afterwards. 705 * 706 * This function assumes that the control handler is locked. 707 */ 708 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); 709 710 /** 711 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed. 712 * 713 * @ctrl: The control to (de)activate. 714 * @grabbed: True if the control should become grabbed. 715 * 716 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically. 717 * Does nothing if @ctrl == NULL. 718 * The V4L2_EVENT_CTRL event will be generated afterwards. 719 * This will usually be called when starting or stopping streaming in the 720 * driver. 721 * 722 * This function assumes that the control handler is not locked and will 723 * take the lock itself. 724 */ 725 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); 726 727 /** 728 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range() 729 * 730 * @ctrl: The control to update. 731 * @min: The control's minimum value. 732 * @max: The control's maximum value. 733 * @step: The control's step value 734 * @def: The control's default value. 735 * 736 * Update the range of a control on the fly. This works for control types 737 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 738 * @step value is interpreted as a menu_skip_mask. 739 * 740 * An error is returned if one of the range arguments is invalid for this 741 * control type. 742 * 743 * This function assumes that the control handler is not locked and will 744 * take the lock itself. 745 */ 746 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 747 s64 min, s64 max, u64 step, s64 def); 748 749 /** 750 * v4l2_ctrl_modify_range() - Update the range of a control. 751 * 752 * @ctrl: The control to update. 753 * @min: The control's minimum value. 754 * @max: The control's maximum value. 755 * @step: The control's step value 756 * @def: The control's default value. 757 * 758 * Update the range of a control on the fly. This works for control types 759 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 760 * @step value is interpreted as a menu_skip_mask. 761 * 762 * An error is returned if one of the range arguments is invalid for this 763 * control type. 764 * 765 * This function assumes that the control handler is not locked and will 766 * take the lock itself. 767 */ 768 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 769 s64 min, s64 max, u64 step, s64 def) 770 { 771 int rval; 772 773 v4l2_ctrl_lock(ctrl); 774 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def); 775 v4l2_ctrl_unlock(ctrl); 776 777 return rval; 778 } 779 780 /** 781 * v4l2_ctrl_notify() - Function to set a notify callback for a control. 782 * 783 * @ctrl: The control. 784 * @notify: The callback function. 785 * @priv: The callback private handle, passed as argument to the callback. 786 * 787 * This function sets a callback function for the control. If @ctrl is NULL, 788 * then it will do nothing. If @notify is NULL, then the notify callback will 789 * be removed. 790 * 791 * There can be only one notify. If another already exists, then a WARN_ON 792 * will be issued and the function will do nothing. 793 */ 794 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, 795 void *priv); 796 797 /** 798 * v4l2_ctrl_get_name() - Get the name of the control 799 * 800 * @id: The control ID. 801 * 802 * This function returns the name of the given control ID or NULL if it isn't 803 * a known control. 804 */ 805 const char *v4l2_ctrl_get_name(u32 id); 806 807 /** 808 * v4l2_ctrl_get_menu() - Get the menu string array of the control 809 * 810 * @id: The control ID. 811 * 812 * This function returns the NULL-terminated menu string array name of the 813 * given control ID or NULL if it isn't a known menu control. 814 */ 815 const char * const *v4l2_ctrl_get_menu(u32 id); 816 817 /** 818 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control 819 * 820 * @id: The control ID. 821 * @len: The size of the integer array. 822 * 823 * This function returns the integer array of the given control ID or NULL if it 824 * if it isn't a known integer menu control. 825 */ 826 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len); 827 828 /** 829 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from 830 * within a driver. 831 * 832 * @ctrl: The control. 833 * 834 * This returns the control's value safely by going through the control 835 * framework. This function will lock the control's handler, so it cannot be 836 * used from within the &v4l2_ctrl_ops functions. 837 * 838 * This function is for integer type controls only. 839 */ 840 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); 841 842 /** 843 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl(). 844 * 845 * @ctrl: The control. 846 * @val: TheControls name new value. 847 * 848 * This sets the control's new value safely by going through the control 849 * framework. This function assumes the control's handler is already locked, 850 * allowing it to be used from within the &v4l2_ctrl_ops functions. 851 * 852 * This function is for integer type controls only. 853 */ 854 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val); 855 856 /** 857 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from 858 * within a driver. 859 * @ctrl: The control. 860 * @val: The new value. 861 * 862 * This sets the control's new value safely by going through the control 863 * framework. This function will lock the control's handler, so it cannot be 864 * used from within the &v4l2_ctrl_ops functions. 865 * 866 * This function is for integer type controls only. 867 */ 868 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) 869 { 870 int rval; 871 872 v4l2_ctrl_lock(ctrl); 873 rval = __v4l2_ctrl_s_ctrl(ctrl, val); 874 v4l2_ctrl_unlock(ctrl); 875 876 return rval; 877 } 878 879 /** 880 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value 881 * from within a driver. 882 * 883 * @ctrl: The control. 884 * 885 * This returns the control's value safely by going through the control 886 * framework. This function will lock the control's handler, so it cannot be 887 * used from within the &v4l2_ctrl_ops functions. 888 * 889 * This function is for 64-bit integer type controls only. 890 */ 891 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl); 892 893 /** 894 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64(). 895 * 896 * @ctrl: The control. 897 * @val: The new value. 898 * 899 * This sets the control's new value safely by going through the control 900 * framework. This function assumes the control's handler is already locked, 901 * allowing it to be used from within the &v4l2_ctrl_ops functions. 902 * 903 * This function is for 64-bit integer type controls only. 904 */ 905 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val); 906 907 /** 908 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value 909 * from within a driver. 910 * 911 * @ctrl: The control. 912 * @val: The new value. 913 * 914 * This sets the control's new value safely by going through the control 915 * framework. This function will lock the control's handler, so it cannot be 916 * used from within the &v4l2_ctrl_ops functions. 917 * 918 * This function is for 64-bit integer type controls only. 919 */ 920 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) 921 { 922 int rval; 923 924 v4l2_ctrl_lock(ctrl); 925 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val); 926 v4l2_ctrl_unlock(ctrl); 927 928 return rval; 929 } 930 931 /** 932 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). 933 * 934 * @ctrl: The control. 935 * @s: The new string. 936 * 937 * This sets the control's new string safely by going through the control 938 * framework. This function assumes the control's handler is already locked, 939 * allowing it to be used from within the &v4l2_ctrl_ops functions. 940 * 941 * This function is for string type controls only. 942 */ 943 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s); 944 945 /** 946 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value 947 * from within a driver. 948 * 949 * @ctrl: The control. 950 * @s: The new string. 951 *Controls name 952 * This sets the control's new string safely by going through the control 953 * framework. This function will lock the control's handler, so it cannot be 954 * used from within the &v4l2_ctrl_ops functions. 955 * 956 * This function is for string type controls only. 957 */ 958 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s) 959 { 960 int rval; 961 962 v4l2_ctrl_lock(ctrl); 963 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s); 964 v4l2_ctrl_unlock(ctrl); 965 966 return rval; 967 } 968 969 /* Internal helper functions that deal with control events. */ 970 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops; 971 972 /** 973 * v4l2_ctrl_replace - Function to be used as a callback to 974 * &struct v4l2_subscribed_event_ops replace\(\) 975 * 976 * @old: pointer to struct &v4l2_event with the reported 977 * event; 978 * @new: pointer to struct &v4l2_event with the modified 979 * event; 980 */ 981 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new); 982 983 /** 984 * v4l2_ctrl_merge - Function to be used as a callback to 985 * &struct v4l2_subscribed_event_ops merge(\) 986 * 987 * @old: pointer to struct &v4l2_event with the reported 988 * event; 989 * @new: pointer to struct &v4l2_event with the merged 990 * event; 991 */ 992 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new); 993 994 /** 995 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl 996 * 997 * @file: pointer to struct file 998 * @fh: unused. Kept just to be compatible to the arguments expected by 999 * &struct v4l2_ioctl_ops.vidioc_log_status. 1000 * 1001 * Can be used as a vidioc_log_status function that just dumps all controls 1002 * associated with the filehandle. 1003 */ 1004 int v4l2_ctrl_log_status(struct file *file, void *fh); 1005 1006 /** 1007 * v4l2_ctrl_subscribe_event - Subscribes to an event 1008 * 1009 * 1010 * @fh: pointer to struct v4l2_fh 1011 * @sub: pointer to &struct v4l2_event_subscription 1012 * 1013 * Can be used as a vidioc_subscribe_event function that just subscribes 1014 * control events. 1015 */ 1016 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, 1017 const struct v4l2_event_subscription *sub); 1018 1019 /** 1020 * v4l2_ctrl_poll - function to be used as a callback to the poll() 1021 * That just polls for control events. 1022 * 1023 * @file: pointer to struct file 1024 * @wait: pointer to struct poll_table_struct 1025 */ 1026 unsigned int v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); 1027 1028 /* Helpers for ioctl_ops */ 1029 1030 /** 1031 * v4l2_queryctrl - Helper function to implement 1032 * :ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl 1033 * 1034 * @hdl: pointer to &struct v4l2_ctrl_handler 1035 * @qc: pointer to &struct v4l2_queryctrl 1036 * 1037 * If hdl == NULL then they will all return -EINVAL. 1038 */ 1039 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc); 1040 1041 /** 1042 * v4l2_query_ext_ctrl - Helper function to implement 1043 * :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl 1044 * 1045 * @hdl: pointer to &struct v4l2_ctrl_handler 1046 * @qc: pointer to &struct v4l2_query_ext_ctrl 1047 * 1048 * If hdl == NULL then they will all return -EINVAL. 1049 */ 1050 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, 1051 struct v4l2_query_ext_ctrl *qc); 1052 1053 /** 1054 * v4l2_querymenu - Helper function to implement 1055 * :ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl 1056 * 1057 * @hdl: pointer to &struct v4l2_ctrl_handler 1058 * @qm: pointer to &struct v4l2_querymenu 1059 * 1060 * If hdl == NULL then they will all return -EINVAL. 1061 */ 1062 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm); 1063 1064 /** 1065 * v4l2_g_ctrl - Helper function to implement 1066 * :ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl 1067 * 1068 * @hdl: pointer to &struct v4l2_ctrl_handler 1069 * @ctrl: pointer to &struct v4l2_control 1070 * 1071 * If hdl == NULL then they will all return -EINVAL. 1072 */ 1073 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl); 1074 1075 /** 1076 * v4l2_s_ctrl - Helper function to implement 1077 * :ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl 1078 * 1079 * @fh: pointer to &struct v4l2_fh 1080 * @hdl: pointer to &struct v4l2_ctrl_handler 1081 * 1082 * @ctrl: pointer to &struct v4l2_control 1083 * 1084 * If hdl == NULL then they will all return -EINVAL. 1085 */ 1086 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1087 struct v4l2_control *ctrl); 1088 1089 /** 1090 * v4l2_g_ext_ctrls - Helper function to implement 1091 * :ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1092 * 1093 * @hdl: pointer to &struct v4l2_ctrl_handler 1094 * @c: pointer to &struct v4l2_ext_controls 1095 * 1096 * If hdl == NULL then they will all return -EINVAL. 1097 */ 1098 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1099 struct v4l2_ext_controls *c); 1100 1101 /** 1102 * v4l2_try_ext_ctrls - Helper function to implement 1103 * :ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1104 * 1105 * @hdl: pointer to &struct v4l2_ctrl_handler 1106 * @c: pointer to &struct v4l2_ext_controls 1107 * 1108 * If hdl == NULL then they will all return -EINVAL. 1109 */ 1110 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1111 struct v4l2_ext_controls *c); 1112 1113 /** 1114 * v4l2_s_ext_ctrls - Helper function to implement 1115 * :ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1116 * 1117 * @fh: pointer to &struct v4l2_fh 1118 * @hdl: pointer to &struct v4l2_ctrl_handler 1119 * @c: pointer to &struct v4l2_ext_controls 1120 * 1121 * If hdl == NULL then they will all return -EINVAL. 1122 */ 1123 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1124 struct v4l2_ext_controls *c); 1125 1126 /** 1127 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement 1128 * as a &struct v4l2_subdev_core_ops subscribe_event function 1129 * that just subscribes control events. 1130 * 1131 * @sd: pointer to &struct v4l2_subdev 1132 * @fh: pointer to &struct v4l2_fh 1133 * @sub: pointer to &struct v4l2_event_subscription 1134 */ 1135 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh, 1136 struct v4l2_event_subscription *sub); 1137 1138 /** 1139 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control 1140 * handler. 1141 * 1142 * @sd: pointer to &struct v4l2_subdev 1143 */ 1144 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd); 1145 1146 #endif 1147