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 * Used only if the @type is %V4L2_CTRL_TYPE_MENU. 170 * @qmenu_int: A 64-bit integer array for with integer menu items. 171 * The size of array must be equal to the menu size, e. g.: 172 * :math:`ceil(\frac{maximum - minimum}{step}) + 1`. 173 * Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU. 174 * @flags: The control's flags. 175 * @cur: Structure to store the current value. 176 * @cur.val: The control's current value, if the @type is represented via 177 * a u32 integer (see &enum v4l2_ctrl_type). 178 * @val: The control's new s32 value. 179 * @priv: The control's private pointer. For use by the driver. It is 180 * untouched by the control framework. Note that this pointer is 181 * not freed when the control is deleted. Should this be needed 182 * then a new internal bitfield can be added to tell the framework 183 * to free this pointer. 184 * @p_cur: The control's current value represented via a union with 185 * provides a standard way of accessing control types 186 * through a pointer. 187 * @p_new: The control's new value represented via a union with provides 188 * a standard way of accessing control types 189 * through a pointer. 190 */ 191 struct v4l2_ctrl { 192 /* Administrative fields */ 193 struct list_head node; 194 struct list_head ev_subs; 195 struct v4l2_ctrl_handler *handler; 196 struct v4l2_ctrl **cluster; 197 unsigned int ncontrols; 198 199 unsigned int done:1; 200 201 unsigned int is_new:1; 202 unsigned int has_changed:1; 203 unsigned int is_private:1; 204 unsigned int is_auto:1; 205 unsigned int is_int:1; 206 unsigned int is_string:1; 207 unsigned int is_ptr:1; 208 unsigned int is_array:1; 209 unsigned int has_volatiles:1; 210 unsigned int call_notify:1; 211 unsigned int manual_mode_value:8; 212 213 const struct v4l2_ctrl_ops *ops; 214 const struct v4l2_ctrl_type_ops *type_ops; 215 u32 id; 216 const char *name; 217 enum v4l2_ctrl_type type; 218 s64 minimum, maximum, default_value; 219 u32 elems; 220 u32 elem_size; 221 u32 dims[V4L2_CTRL_MAX_DIMS]; 222 u32 nr_of_dims; 223 union { 224 u64 step; 225 u64 menu_skip_mask; 226 }; 227 union { 228 const char * const *qmenu; 229 const s64 *qmenu_int; 230 }; 231 unsigned long flags; 232 void *priv; 233 s32 val; 234 struct { 235 s32 val; 236 } cur; 237 238 union v4l2_ctrl_ptr p_new; 239 union v4l2_ctrl_ptr p_cur; 240 }; 241 242 /** 243 * struct v4l2_ctrl_ref - The control reference. 244 * 245 * @node: List node for the sorted list. 246 * @next: Single-link list node for the hash. 247 * @ctrl: The actual control information. 248 * @helper: Pointer to helper struct. Used internally in 249 * ``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``. 250 * 251 * Each control handler has a list of these refs. The list_head is used to 252 * keep a sorted-by-control-ID list of all controls, while the next pointer 253 * is used to link the control in the hash's bucket. 254 */ 255 struct v4l2_ctrl_ref { 256 struct list_head node; 257 struct v4l2_ctrl_ref *next; 258 struct v4l2_ctrl *ctrl; 259 struct v4l2_ctrl_helper *helper; 260 }; 261 262 /** 263 * struct v4l2_ctrl_handler - The control handler keeps track of all the 264 * controls: both the controls owned by the handler and those inherited 265 * from other handlers. 266 * 267 * @_lock: Default for "lock". 268 * @lock: Lock to control access to this handler and its controls. 269 * May be replaced by the user right after init. 270 * @ctrls: The list of controls owned by this handler. 271 * @ctrl_refs: The list of control references. 272 * @cached: The last found control reference. It is common that the same 273 * control is needed multiple times, so this is a simple 274 * optimization. 275 * @buckets: Buckets for the hashing. Allows for quick control lookup. 276 * @notify: A notify callback that is called whenever the control changes 277 * value. 278 * Note that the handler's lock is held when the notify function 279 * is called! 280 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback. 281 * @nr_of_buckets: Total number of buckets in the array. 282 * @error: The error code of the first failed control addition. 283 */ 284 struct v4l2_ctrl_handler { 285 struct mutex _lock; 286 struct mutex *lock; 287 struct list_head ctrls; 288 struct list_head ctrl_refs; 289 struct v4l2_ctrl_ref *cached; 290 struct v4l2_ctrl_ref **buckets; 291 v4l2_ctrl_notify_fnc notify; 292 void *notify_priv; 293 u16 nr_of_buckets; 294 int error; 295 }; 296 297 /** 298 * struct v4l2_ctrl_config - Control configuration structure. 299 * 300 * @ops: The control ops. 301 * @type_ops: The control type ops. Only needed for compound controls. 302 * @id: The control ID. 303 * @name: The control name. 304 * @type: The control type. 305 * @min: The control's minimum value. 306 * @max: The control's maximum value. 307 * @step: The control's step value for non-menu controls. 308 * @def: The control's default value. 309 * @dims: The size of each dimension. 310 * @elem_size: The size in bytes of the control. 311 * @flags: The control's flags. 312 * @menu_skip_mask: The control's skip mask for menu controls. This makes it 313 * easy to skip menu items that are not valid. If bit X is set, 314 * then menu item X is skipped. Of course, this only works for 315 * menus with <= 64 menu items. There are no menus that come 316 * close to that number, so this is OK. Should we ever need more, 317 * then this will have to be extended to a bit array. 318 * @qmenu: A const char * array for all menu items. Array entries that are 319 * empty strings ("") correspond to non-existing menu items (this 320 * is in addition to the menu_skip_mask above). The last entry 321 * must be NULL. 322 * @qmenu_int: A const s64 integer array for all menu items of the type 323 * V4L2_CTRL_TYPE_INTEGER_MENU. 324 * @is_private: If set, then this control is private to its handler and it 325 * will not be added to any other handlers. 326 */ 327 struct v4l2_ctrl_config { 328 const struct v4l2_ctrl_ops *ops; 329 const struct v4l2_ctrl_type_ops *type_ops; 330 u32 id; 331 const char *name; 332 enum v4l2_ctrl_type type; 333 s64 min; 334 s64 max; 335 u64 step; 336 s64 def; 337 u32 dims[V4L2_CTRL_MAX_DIMS]; 338 u32 elem_size; 339 u32 flags; 340 u64 menu_skip_mask; 341 const char * const *qmenu; 342 const s64 *qmenu_int; 343 unsigned int is_private:1; 344 }; 345 346 /** 347 * v4l2_ctrl_fill - Fill in the control fields based on the control ID. 348 * 349 * @id: ID of the control 350 * @name: pointer to be filled with a string with the name of the control 351 * @type: pointer for storing the type of the control 352 * @min: pointer for storing the minimum value for the control 353 * @max: pointer for storing the maximum value for the control 354 * @step: pointer for storing the control step 355 * @def: pointer for storing the default value for the control 356 * @flags: pointer for storing the flags to be used on the control 357 * 358 * This works for all standard V4L2 controls. 359 * For non-standard controls it will only fill in the given arguments 360 * and @name content will be set to %NULL. 361 * 362 * This function will overwrite the contents of @name, @type and @flags. 363 * The contents of @min, @max, @step and @def may be modified depending on 364 * the type. 365 * 366 * .. note:: 367 * 368 * Do not use in drivers! It is used internally for backwards compatibility 369 * control handling only. Once all drivers are converted to use the new 370 * control framework this function will no longer be exported. 371 */ 372 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, 373 s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags); 374 375 376 /** 377 * v4l2_ctrl_handler_init_class() - Initialize the control handler. 378 * @hdl: The control handler. 379 * @nr_of_controls_hint: A hint of how many controls this handler is 380 * expected to refer to. This is the total number, so including 381 * any inherited controls. It doesn't have to be precise, but if 382 * it is way off, then you either waste memory (too many buckets 383 * are allocated) or the control lookup becomes slower (not enough 384 * buckets are allocated, so there are more slow list lookups). 385 * It will always work, though. 386 * @key: Used by the lock validator if CONFIG_LOCKDEP is set. 387 * @name: Used by the lock validator if CONFIG_LOCKDEP is set. 388 * 389 * .. attention:: 390 * 391 * Never use this call directly, always use the v4l2_ctrl_handler_init() 392 * macro that hides the @key and @name arguments. 393 * 394 * Return: returns an error if the buckets could not be allocated. This 395 * error will also be stored in @hdl->error. 396 */ 397 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl, 398 unsigned int nr_of_controls_hint, 399 struct lock_class_key *key, const char *name); 400 401 #ifdef CONFIG_LOCKDEP 402 403 /** 404 * v4l2_ctrl_handler_init - helper function to create a static struct 405 * &lock_class_key and calls v4l2_ctrl_handler_init_class() 406 * 407 * @hdl: The control handler. 408 * @nr_of_controls_hint: A hint of how many controls this handler is 409 * expected to refer to. This is the total number, so including 410 * any inherited controls. It doesn't have to be precise, but if 411 * it is way off, then you either waste memory (too many buckets 412 * are allocated) or the control lookup becomes slower (not enough 413 * buckets are allocated, so there are more slow list lookups). 414 * It will always work, though. 415 * 416 * This helper function creates a static struct &lock_class_key and 417 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock 418 * validador. 419 * 420 * Use this helper function to initialize a control handler. 421 */ 422 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 423 ( \ 424 ({ \ 425 static struct lock_class_key _key; \ 426 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \ 427 &_key, \ 428 KBUILD_BASENAME ":" \ 429 __stringify(__LINE__) ":" \ 430 "(" #hdl ")->_lock"); \ 431 }) \ 432 ) 433 #else 434 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 435 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL) 436 #endif 437 438 /** 439 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free 440 * the control list. 441 * @hdl: The control handler. 442 * 443 * Does nothing if @hdl == NULL. 444 */ 445 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl); 446 447 /** 448 * v4l2_ctrl_lock() - Helper function to lock the handler 449 * associated with the control. 450 * @ctrl: The control to lock. 451 */ 452 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) 453 { 454 mutex_lock(ctrl->handler->lock); 455 } 456 457 /** 458 * v4l2_ctrl_unlock() - Helper function to unlock the handler 459 * associated with the control. 460 * @ctrl: The control to unlock. 461 */ 462 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl) 463 { 464 mutex_unlock(ctrl->handler->lock); 465 } 466 467 /** 468 * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging 469 * to the handler to initialize the hardware to the current control values. The 470 * caller is responsible for acquiring the control handler mutex on behalf of 471 * __v4l2_ctrl_handler_setup(). 472 * @hdl: The control handler. 473 * 474 * Button controls will be skipped, as are read-only controls. 475 * 476 * If @hdl == NULL, then this just returns 0. 477 */ 478 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl); 479 480 /** 481 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging 482 * to the handler to initialize the hardware to the current control values. 483 * @hdl: The control handler. 484 * 485 * Button controls will be skipped, as are read-only controls. 486 * 487 * If @hdl == NULL, then this just returns 0. 488 */ 489 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl); 490 491 /** 492 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler. 493 * @hdl: The control handler. 494 * @prefix: The prefix to use when logging the control values. If the 495 * prefix does not end with a space, then ": " will be added 496 * after the prefix. If @prefix == NULL, then no prefix will be 497 * used. 498 * 499 * For use with VIDIOC_LOG_STATUS. 500 * 501 * Does nothing if @hdl == NULL. 502 */ 503 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, 504 const char *prefix); 505 506 /** 507 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2 508 * control. 509 * 510 * @hdl: The control handler. 511 * @cfg: The control's configuration data. 512 * @priv: The control's driver-specific private data. 513 * 514 * If the &v4l2_ctrl struct could not be allocated then NULL is returned 515 * and @hdl->error is set to the error code (if it wasn't set already). 516 */ 517 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, 518 const struct v4l2_ctrl_config *cfg, 519 void *priv); 520 521 /** 522 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu 523 * control. 524 * 525 * @hdl: The control handler. 526 * @ops: The control ops. 527 * @id: The control ID. 528 * @min: The control's minimum value. 529 * @max: The control's maximum value. 530 * @step: The control's step value 531 * @def: The control's default value. 532 * 533 * If the &v4l2_ctrl struct could not be allocated, or the control 534 * ID is not known, then NULL is returned and @hdl->error is set to the 535 * appropriate error code (if it wasn't set already). 536 * 537 * If @id refers to a menu control, then this function will return NULL. 538 * 539 * Use v4l2_ctrl_new_std_menu() when adding menu controls. 540 */ 541 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, 542 const struct v4l2_ctrl_ops *ops, 543 u32 id, s64 min, s64 max, u64 step, 544 s64 def); 545 546 /** 547 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 548 * menu control. 549 * 550 * @hdl: The control handler. 551 * @ops: The control ops. 552 * @id: The control ID. 553 * @max: The control's maximum value. 554 * @mask: The control's skip mask for menu controls. This makes it 555 * easy to skip menu items that are not valid. If bit X is set, 556 * then menu item X is skipped. Of course, this only works for 557 * menus with <= 64 menu items. There are no menus that come 558 * close to that number, so this is OK. Should we ever need more, 559 * then this will have to be extended to a bit array. 560 * @def: The control's default value. 561 * 562 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value 563 * determines which menu items are to be skipped. 564 * 565 * If @id refers to a non-menu control, then this function will return NULL. 566 */ 567 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, 568 const struct v4l2_ctrl_ops *ops, 569 u32 id, u8 max, u64 mask, u8 def); 570 571 /** 572 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control 573 * with driver specific menu. 574 * 575 * @hdl: The control handler. 576 * @ops: The control ops. 577 * @id: The control ID. 578 * @max: The control's maximum value. 579 * @mask: The control's skip mask for menu controls. This makes it 580 * easy to skip menu items that are not valid. If bit X is set, 581 * then menu item X is skipped. Of course, this only works for 582 * menus with <= 64 menu items. There are no menus that come 583 * close to that number, so this is OK. Should we ever need more, 584 * then this will have to be extended to a bit array. 585 * @def: The control's default value. 586 * @qmenu: The new menu. 587 * 588 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific 589 * menu of this control. 590 * 591 */ 592 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, 593 const struct v4l2_ctrl_ops *ops, 594 u32 id, u8 max, 595 u64 mask, u8 def, 596 const char * const *qmenu); 597 598 /** 599 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control. 600 * 601 * @hdl: The control handler. 602 * @ops: The control ops. 603 * @id: The control ID. 604 * @max: The control's maximum value. 605 * @def: The control's default value. 606 * @qmenu_int: The control's menu entries. 607 * 608 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly 609 * takes as an argument an array of integers determining the menu items. 610 * 611 * If @id refers to a non-integer-menu control, then this function will 612 * return %NULL. 613 */ 614 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl, 615 const struct v4l2_ctrl_ops *ops, 616 u32 id, u8 max, u8 def, 617 const s64 *qmenu_int); 618 619 /** 620 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be 621 * used when adding a control handler. 622 * 623 * @ctrl: pointer to struct &v4l2_ctrl. 624 */ 625 626 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl); 627 628 /** 629 * v4l2_ctrl_add_handler() - Add all controls from handler @add to 630 * handler @hdl. 631 * 632 * @hdl: The control handler. 633 * @add: The control handler whose controls you want to add to 634 * the @hdl control handler. 635 * @filter: This function will filter which controls should be added. 636 * 637 * Does nothing if either of the two handlers is a NULL pointer. 638 * If @filter is NULL, then all controls are added. Otherwise only those 639 * controls for which @filter returns true will be added. 640 * In case of an error @hdl->error will be set to the error code (if it 641 * wasn't set already). 642 */ 643 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, 644 struct v4l2_ctrl_handler *add, 645 v4l2_ctrl_filter filter); 646 647 /** 648 * v4l2_ctrl_radio_filter() - Standard filter for radio controls. 649 * 650 * @ctrl: The control that is filtered. 651 * 652 * This will return true for any controls that are valid for radio device 653 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM 654 * transmitter class controls. 655 * 656 * This function is to be used with v4l2_ctrl_add_handler(). 657 */ 658 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl); 659 660 /** 661 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging 662 * to that cluster. 663 * 664 * @ncontrols: The number of controls in this cluster. 665 * @controls: The cluster control array of size @ncontrols. 666 */ 667 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls); 668 669 670 /** 671 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging 672 * to that cluster and set it up for autofoo/foo-type handling. 673 * 674 * @ncontrols: The number of controls in this cluster. 675 * @controls: The cluster control array of size @ncontrols. The first control 676 * must be the 'auto' control (e.g. autogain, autoexposure, etc.) 677 * @manual_val: The value for the first control in the cluster that equals the 678 * manual setting. 679 * @set_volatile: If true, then all controls except the first auto control will 680 * be volatile. 681 * 682 * Use for control groups where one control selects some automatic feature and 683 * the other controls are only active whenever the automatic feature is turned 684 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs 685 * red and blue balance, etc. 686 * 687 * The behavior of such controls is as follows: 688 * 689 * When the autofoo control is set to automatic, then any manual controls 690 * are set to inactive and any reads will call g_volatile_ctrl (if the control 691 * was marked volatile). 692 * 693 * When the autofoo control is set to manual, then any manual controls will 694 * be marked active, and any reads will just return the current value without 695 * going through g_volatile_ctrl. 696 * 697 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag 698 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s) 699 * if autofoo is in auto mode. 700 */ 701 void v4l2_ctrl_auto_cluster(unsigned int ncontrols, 702 struct v4l2_ctrl **controls, 703 u8 manual_val, bool set_volatile); 704 705 706 /** 707 * v4l2_ctrl_find() - Find a control with the given ID. 708 * 709 * @hdl: The control handler. 710 * @id: The control ID to find. 711 * 712 * If @hdl == NULL this will return NULL as well. Will lock the handler so 713 * do not use from inside &v4l2_ctrl_ops. 714 */ 715 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id); 716 717 /** 718 * v4l2_ctrl_activate() - Make the control active or inactive. 719 * @ctrl: The control to (de)activate. 720 * @active: True if the control should become active. 721 * 722 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically. 723 * Does nothing if @ctrl == NULL. 724 * This will usually be called from within the s_ctrl op. 725 * The V4L2_EVENT_CTRL event will be generated afterwards. 726 * 727 * This function assumes that the control handler is locked. 728 */ 729 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); 730 731 /** 732 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed. 733 * 734 * @ctrl: The control to (de)activate. 735 * @grabbed: True if the control should become grabbed. 736 * 737 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically. 738 * Does nothing if @ctrl == NULL. 739 * The V4L2_EVENT_CTRL event will be generated afterwards. 740 * This will usually be called when starting or stopping streaming in the 741 * driver. 742 * 743 * This function assumes that the control handler is not locked and will 744 * take the lock itself. 745 */ 746 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); 747 748 /** 749 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range() 750 * 751 * @ctrl: The control to update. 752 * @min: The control's minimum value. 753 * @max: The control's maximum value. 754 * @step: The control's step value 755 * @def: The control's default value. 756 * 757 * Update the range of a control on the fly. This works for control types 758 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 759 * @step value is interpreted as a menu_skip_mask. 760 * 761 * An error is returned if one of the range arguments is invalid for this 762 * control type. 763 * 764 * This function assumes that the control handler is not locked and will 765 * take the lock itself. 766 */ 767 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 768 s64 min, s64 max, u64 step, s64 def); 769 770 /** 771 * v4l2_ctrl_modify_range() - Update the range of a control. 772 * 773 * @ctrl: The control to update. 774 * @min: The control's minimum value. 775 * @max: The control's maximum value. 776 * @step: The control's step value 777 * @def: The control's default value. 778 * 779 * Update the range of a control on the fly. This works for control types 780 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 781 * @step value is interpreted as a menu_skip_mask. 782 * 783 * An error is returned if one of the range arguments is invalid for this 784 * control type. 785 * 786 * This function assumes that the control handler is not locked and will 787 * take the lock itself. 788 */ 789 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 790 s64 min, s64 max, u64 step, s64 def) 791 { 792 int rval; 793 794 v4l2_ctrl_lock(ctrl); 795 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def); 796 v4l2_ctrl_unlock(ctrl); 797 798 return rval; 799 } 800 801 /** 802 * v4l2_ctrl_notify() - Function to set a notify callback for a control. 803 * 804 * @ctrl: The control. 805 * @notify: The callback function. 806 * @priv: The callback private handle, passed as argument to the callback. 807 * 808 * This function sets a callback function for the control. If @ctrl is NULL, 809 * then it will do nothing. If @notify is NULL, then the notify callback will 810 * be removed. 811 * 812 * There can be only one notify. If another already exists, then a WARN_ON 813 * will be issued and the function will do nothing. 814 */ 815 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, 816 void *priv); 817 818 /** 819 * v4l2_ctrl_get_name() - Get the name of the control 820 * 821 * @id: The control ID. 822 * 823 * This function returns the name of the given control ID or NULL if it isn't 824 * a known control. 825 */ 826 const char *v4l2_ctrl_get_name(u32 id); 827 828 /** 829 * v4l2_ctrl_get_menu() - Get the menu string array of the control 830 * 831 * @id: The control ID. 832 * 833 * This function returns the NULL-terminated menu string array name of the 834 * given control ID or NULL if it isn't a known menu control. 835 */ 836 const char * const *v4l2_ctrl_get_menu(u32 id); 837 838 /** 839 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control 840 * 841 * @id: The control ID. 842 * @len: The size of the integer array. 843 * 844 * This function returns the integer array of the given control ID or NULL if it 845 * if it isn't a known integer menu control. 846 */ 847 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len); 848 849 /** 850 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from 851 * within a driver. 852 * 853 * @ctrl: The control. 854 * 855 * This returns the control's value safely by going through the control 856 * framework. This function will lock the control's handler, so it cannot be 857 * used from within the &v4l2_ctrl_ops functions. 858 * 859 * This function is for integer type controls only. 860 */ 861 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); 862 863 /** 864 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl(). 865 * 866 * @ctrl: The control. 867 * @val: TheControls name new value. 868 * 869 * This sets the control's new value safely by going through the control 870 * framework. This function assumes the control's handler is already locked, 871 * allowing it to be used from within the &v4l2_ctrl_ops functions. 872 * 873 * This function is for integer type controls only. 874 */ 875 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val); 876 877 /** 878 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from 879 * within a driver. 880 * @ctrl: The control. 881 * @val: The new value. 882 * 883 * This sets the control's new value safely by going through the control 884 * framework. This function will lock the control's handler, so it cannot be 885 * used from within the &v4l2_ctrl_ops functions. 886 * 887 * This function is for integer type controls only. 888 */ 889 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) 890 { 891 int rval; 892 893 v4l2_ctrl_lock(ctrl); 894 rval = __v4l2_ctrl_s_ctrl(ctrl, val); 895 v4l2_ctrl_unlock(ctrl); 896 897 return rval; 898 } 899 900 /** 901 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value 902 * from within a driver. 903 * 904 * @ctrl: The control. 905 * 906 * This returns the control's value safely by going through the control 907 * framework. This function will lock the control's handler, so it cannot be 908 * used from within the &v4l2_ctrl_ops functions. 909 * 910 * This function is for 64-bit integer type controls only. 911 */ 912 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl); 913 914 /** 915 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64(). 916 * 917 * @ctrl: The control. 918 * @val: The new value. 919 * 920 * This sets the control's new value safely by going through the control 921 * framework. This function assumes the control's handler is already locked, 922 * allowing it to be used from within the &v4l2_ctrl_ops functions. 923 * 924 * This function is for 64-bit integer type controls only. 925 */ 926 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val); 927 928 /** 929 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value 930 * from within a driver. 931 * 932 * @ctrl: The control. 933 * @val: The new value. 934 * 935 * This sets the control's new value safely by going through the control 936 * framework. This function will lock the control's handler, so it cannot be 937 * used from within the &v4l2_ctrl_ops functions. 938 * 939 * This function is for 64-bit integer type controls only. 940 */ 941 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) 942 { 943 int rval; 944 945 v4l2_ctrl_lock(ctrl); 946 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val); 947 v4l2_ctrl_unlock(ctrl); 948 949 return rval; 950 } 951 952 /** 953 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). 954 * 955 * @ctrl: The control. 956 * @s: The new string. 957 * 958 * This sets the control's new string safely by going through the control 959 * framework. This function assumes the control's handler is already locked, 960 * allowing it to be used from within the &v4l2_ctrl_ops functions. 961 * 962 * This function is for string type controls only. 963 */ 964 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s); 965 966 /** 967 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value 968 * from within a driver. 969 * 970 * @ctrl: The control. 971 * @s: The new string. 972 *Controls name 973 * This sets the control's new string safely by going through the control 974 * framework. This function will lock the control's handler, so it cannot be 975 * used from within the &v4l2_ctrl_ops functions. 976 * 977 * This function is for string type controls only. 978 */ 979 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s) 980 { 981 int rval; 982 983 v4l2_ctrl_lock(ctrl); 984 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s); 985 v4l2_ctrl_unlock(ctrl); 986 987 return rval; 988 } 989 990 /* Internal helper functions that deal with control events. */ 991 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops; 992 993 /** 994 * v4l2_ctrl_replace - Function to be used as a callback to 995 * &struct v4l2_subscribed_event_ops replace\(\) 996 * 997 * @old: pointer to struct &v4l2_event with the reported 998 * event; 999 * @new: pointer to struct &v4l2_event with the modified 1000 * event; 1001 */ 1002 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new); 1003 1004 /** 1005 * v4l2_ctrl_merge - Function to be used as a callback to 1006 * &struct v4l2_subscribed_event_ops merge(\) 1007 * 1008 * @old: pointer to struct &v4l2_event with the reported 1009 * event; 1010 * @new: pointer to struct &v4l2_event with the merged 1011 * event; 1012 */ 1013 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new); 1014 1015 /** 1016 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl 1017 * 1018 * @file: pointer to struct file 1019 * @fh: unused. Kept just to be compatible to the arguments expected by 1020 * &struct v4l2_ioctl_ops.vidioc_log_status. 1021 * 1022 * Can be used as a vidioc_log_status function that just dumps all controls 1023 * associated with the filehandle. 1024 */ 1025 int v4l2_ctrl_log_status(struct file *file, void *fh); 1026 1027 /** 1028 * v4l2_ctrl_subscribe_event - Subscribes to an event 1029 * 1030 * 1031 * @fh: pointer to struct v4l2_fh 1032 * @sub: pointer to &struct v4l2_event_subscription 1033 * 1034 * Can be used as a vidioc_subscribe_event function that just subscribes 1035 * control events. 1036 */ 1037 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, 1038 const struct v4l2_event_subscription *sub); 1039 1040 /** 1041 * v4l2_ctrl_poll - function to be used as a callback to the poll() 1042 * That just polls for control events. 1043 * 1044 * @file: pointer to struct file 1045 * @wait: pointer to struct poll_table_struct 1046 */ 1047 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); 1048 1049 /* Helpers for ioctl_ops */ 1050 1051 /** 1052 * v4l2_queryctrl - Helper function to implement 1053 * :ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl 1054 * 1055 * @hdl: pointer to &struct v4l2_ctrl_handler 1056 * @qc: pointer to &struct v4l2_queryctrl 1057 * 1058 * If hdl == NULL then they will all return -EINVAL. 1059 */ 1060 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc); 1061 1062 /** 1063 * v4l2_query_ext_ctrl - Helper function to implement 1064 * :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl 1065 * 1066 * @hdl: pointer to &struct v4l2_ctrl_handler 1067 * @qc: pointer to &struct v4l2_query_ext_ctrl 1068 * 1069 * If hdl == NULL then they will all return -EINVAL. 1070 */ 1071 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, 1072 struct v4l2_query_ext_ctrl *qc); 1073 1074 /** 1075 * v4l2_querymenu - Helper function to implement 1076 * :ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl 1077 * 1078 * @hdl: pointer to &struct v4l2_ctrl_handler 1079 * @qm: pointer to &struct v4l2_querymenu 1080 * 1081 * If hdl == NULL then they will all return -EINVAL. 1082 */ 1083 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm); 1084 1085 /** 1086 * v4l2_g_ctrl - Helper function to implement 1087 * :ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl 1088 * 1089 * @hdl: pointer to &struct v4l2_ctrl_handler 1090 * @ctrl: pointer to &struct v4l2_control 1091 * 1092 * If hdl == NULL then they will all return -EINVAL. 1093 */ 1094 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl); 1095 1096 /** 1097 * v4l2_s_ctrl - Helper function to implement 1098 * :ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl 1099 * 1100 * @fh: pointer to &struct v4l2_fh 1101 * @hdl: pointer to &struct v4l2_ctrl_handler 1102 * 1103 * @ctrl: pointer to &struct v4l2_control 1104 * 1105 * If hdl == NULL then they will all return -EINVAL. 1106 */ 1107 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1108 struct v4l2_control *ctrl); 1109 1110 /** 1111 * v4l2_g_ext_ctrls - Helper function to implement 1112 * :ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1113 * 1114 * @hdl: pointer to &struct v4l2_ctrl_handler 1115 * @c: pointer to &struct v4l2_ext_controls 1116 * 1117 * If hdl == NULL then they will all return -EINVAL. 1118 */ 1119 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1120 struct v4l2_ext_controls *c); 1121 1122 /** 1123 * v4l2_try_ext_ctrls - Helper function to implement 1124 * :ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1125 * 1126 * @hdl: pointer to &struct v4l2_ctrl_handler 1127 * @c: pointer to &struct v4l2_ext_controls 1128 * 1129 * If hdl == NULL then they will all return -EINVAL. 1130 */ 1131 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1132 struct v4l2_ext_controls *c); 1133 1134 /** 1135 * v4l2_s_ext_ctrls - Helper function to implement 1136 * :ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1137 * 1138 * @fh: pointer to &struct v4l2_fh 1139 * @hdl: pointer to &struct v4l2_ctrl_handler 1140 * @c: pointer to &struct v4l2_ext_controls 1141 * 1142 * If hdl == NULL then they will all return -EINVAL. 1143 */ 1144 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1145 struct v4l2_ext_controls *c); 1146 1147 /** 1148 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement 1149 * as a &struct v4l2_subdev_core_ops subscribe_event function 1150 * that just subscribes control events. 1151 * 1152 * @sd: pointer to &struct v4l2_subdev 1153 * @fh: pointer to &struct v4l2_fh 1154 * @sub: pointer to &struct v4l2_event_subscription 1155 */ 1156 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh, 1157 struct v4l2_event_subscription *sub); 1158 1159 /** 1160 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control 1161 * handler. 1162 * 1163 * @sd: pointer to &struct v4l2_subdev 1164 */ 1165 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd); 1166 1167 #endif 1168