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 a 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 a 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 - helper function to create a static struct 398 * &lock_class_key and calls v4l2_ctrl_handler_init_class() 399 * 400 * @hdl: The control handler. 401 * @nr_of_controls_hint: A hint of how many controls this handler is 402 * expected to refer to. This is the total number, so including 403 * any inherited controls. It doesn't have to be precise, but if 404 * it is way off, then you either waste memory (too many buckets 405 * are allocated) or the control lookup becomes slower (not enough 406 * buckets are allocated, so there are more slow list lookups). 407 * It will always work, though. 408 * 409 * This helper function creates a static struct &lock_class_key and 410 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock 411 * validador. 412 * 413 * Use this helper function to initialize a control handler. 414 */ 415 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 416 ( \ 417 ({ \ 418 static struct lock_class_key _key; \ 419 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \ 420 &_key, \ 421 KBUILD_BASENAME ":" \ 422 __stringify(__LINE__) ":" \ 423 "(" #hdl ")->_lock"); \ 424 }) \ 425 ) 426 #else 427 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \ 428 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL) 429 #endif 430 431 /** 432 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free 433 * the control list. 434 * @hdl: The control handler. 435 * 436 * Does nothing if @hdl == NULL. 437 */ 438 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl); 439 440 /** 441 * v4l2_ctrl_lock() - Helper function to lock the handler 442 * associated with the control. 443 * @ctrl: The control to lock. 444 */ 445 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) 446 { 447 mutex_lock(ctrl->handler->lock); 448 } 449 450 /** 451 * v4l2_ctrl_unlock() - Helper function to unlock the handler 452 * associated with the control. 453 * @ctrl: The control to unlock. 454 */ 455 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl) 456 { 457 mutex_unlock(ctrl->handler->lock); 458 } 459 460 /** 461 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging 462 * to the handler to initialize the hardware to the current control values. 463 * @hdl: The control handler. 464 * 465 * Button controls will be skipped, as are read-only controls. 466 * 467 * If @hdl == NULL, then this just returns 0. 468 */ 469 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl); 470 471 /** 472 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler. 473 * @hdl: The control handler. 474 * @prefix: The prefix to use when logging the control values. If the 475 * prefix does not end with a space, then ": " will be added 476 * after the prefix. If @prefix == NULL, then no prefix will be 477 * used. 478 * 479 * For use with VIDIOC_LOG_STATUS. 480 * 481 * Does nothing if @hdl == NULL. 482 */ 483 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, 484 const char *prefix); 485 486 /** 487 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2 488 * control. 489 * 490 * @hdl: The control handler. 491 * @cfg: The control's configuration data. 492 * @priv: The control's driver-specific private data. 493 * 494 * If the &v4l2_ctrl struct could not be allocated then NULL is returned 495 * and @hdl->error is set to the error code (if it wasn't set already). 496 */ 497 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, 498 const struct v4l2_ctrl_config *cfg, 499 void *priv); 500 501 /** 502 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu 503 * control. 504 * 505 * @hdl: The control handler. 506 * @ops: The control ops. 507 * @id: The control ID. 508 * @min: The control's minimum value. 509 * @max: The control's maximum value. 510 * @step: The control's step value 511 * @def: The control's default value. 512 * 513 * If the &v4l2_ctrl struct could not be allocated, or the control 514 * ID is not known, then NULL is returned and @hdl->error is set to the 515 * appropriate error code (if it wasn't set already). 516 * 517 * If @id refers to a menu control, then this function will return NULL. 518 * 519 * Use v4l2_ctrl_new_std_menu() when adding menu controls. 520 */ 521 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, 522 const struct v4l2_ctrl_ops *ops, 523 u32 id, s64 min, s64 max, u64 step, 524 s64 def); 525 526 /** 527 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 528 * menu control. 529 * 530 * @hdl: The control handler. 531 * @ops: The control ops. 532 * @id: The control ID. 533 * @max: The control's maximum value. 534 * @mask: The control's skip mask for menu controls. This makes it 535 * easy to skip menu items that are not valid. If bit X is set, 536 * then menu item X is skipped. Of course, this only works for 537 * menus with <= 64 menu items. There are no menus that come 538 * close to that number, so this is OK. Should we ever need more, 539 * then this will have to be extended to a bit array. 540 * @def: The control's default value. 541 * 542 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value 543 * determines which menu items are to be skipped. 544 * 545 * If @id refers to a non-menu control, then this function will return NULL. 546 */ 547 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, 548 const struct v4l2_ctrl_ops *ops, 549 u32 id, u8 max, u64 mask, u8 def); 550 551 /** 552 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control 553 * with driver specific menu. 554 * 555 * @hdl: The control handler. 556 * @ops: The control ops. 557 * @id: The control ID. 558 * @max: The control's maximum value. 559 * @mask: The control's skip mask for menu controls. This makes it 560 * easy to skip menu items that are not valid. If bit X is set, 561 * then menu item X is skipped. Of course, this only works for 562 * menus with <= 64 menu items. There are no menus that come 563 * close to that number, so this is OK. Should we ever need more, 564 * then this will have to be extended to a bit array. 565 * @def: The control's default value. 566 * @qmenu: The new menu. 567 * 568 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific 569 * menu of this control. 570 * 571 */ 572 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, 573 const struct v4l2_ctrl_ops *ops, 574 u32 id, u8 max, 575 u64 mask, u8 def, 576 const char * const *qmenu); 577 578 /** 579 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control. 580 * 581 * @hdl: The control handler. 582 * @ops: The control ops. 583 * @id: The control ID. 584 * @max: The control's maximum value. 585 * @def: The control's default value. 586 * @qmenu_int: The control's menu entries. 587 * 588 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly 589 * takes as an argument an array of integers determining the menu items. 590 * 591 * If @id refers to a non-integer-menu control, then this function will 592 * return %NULL. 593 */ 594 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl, 595 const struct v4l2_ctrl_ops *ops, 596 u32 id, u8 max, u8 def, 597 const s64 *qmenu_int); 598 599 /** 600 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be 601 * used when adding a control handler. 602 * 603 * @ctrl: pointer to struct &v4l2_ctrl. 604 */ 605 606 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl); 607 608 /** 609 * v4l2_ctrl_add_handler() - Add all controls from handler @add to 610 * handler @hdl. 611 * 612 * @hdl: The control handler. 613 * @add: The control handler whose controls you want to add to 614 * the @hdl control handler. 615 * @filter: This function will filter which controls should be added. 616 * 617 * Does nothing if either of the two handlers is a NULL pointer. 618 * If @filter is NULL, then all controls are added. Otherwise only those 619 * controls for which @filter returns true will be added. 620 * In case of an error @hdl->error will be set to the error code (if it 621 * wasn't set already). 622 */ 623 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, 624 struct v4l2_ctrl_handler *add, 625 v4l2_ctrl_filter filter); 626 627 /** 628 * v4l2_ctrl_radio_filter() - Standard filter for radio controls. 629 * 630 * @ctrl: The control that is filtered. 631 * 632 * This will return true for any controls that are valid for radio device 633 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM 634 * transmitter class controls. 635 * 636 * This function is to be used with v4l2_ctrl_add_handler(). 637 */ 638 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl); 639 640 /** 641 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging 642 * to that cluster. 643 * 644 * @ncontrols: The number of controls in this cluster. 645 * @controls: The cluster control array of size @ncontrols. 646 */ 647 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls); 648 649 650 /** 651 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging 652 * to that cluster and set it up for autofoo/foo-type handling. 653 * 654 * @ncontrols: The number of controls in this cluster. 655 * @controls: The cluster control array of size @ncontrols. The first control 656 * must be the 'auto' control (e.g. autogain, autoexposure, etc.) 657 * @manual_val: The value for the first control in the cluster that equals the 658 * manual setting. 659 * @set_volatile: If true, then all controls except the first auto control will 660 * be volatile. 661 * 662 * Use for control groups where one control selects some automatic feature and 663 * the other controls are only active whenever the automatic feature is turned 664 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs 665 * red and blue balance, etc. 666 * 667 * The behavior of such controls is as follows: 668 * 669 * When the autofoo control is set to automatic, then any manual controls 670 * are set to inactive and any reads will call g_volatile_ctrl (if the control 671 * was marked volatile). 672 * 673 * When the autofoo control is set to manual, then any manual controls will 674 * be marked active, and any reads will just return the current value without 675 * going through g_volatile_ctrl. 676 * 677 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag 678 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s) 679 * if autofoo is in auto mode. 680 */ 681 void v4l2_ctrl_auto_cluster(unsigned int ncontrols, 682 struct v4l2_ctrl **controls, 683 u8 manual_val, bool set_volatile); 684 685 686 /** 687 * v4l2_ctrl_find() - Find a control with the given ID. 688 * 689 * @hdl: The control handler. 690 * @id: The control ID to find. 691 * 692 * If @hdl == NULL this will return NULL as well. Will lock the handler so 693 * do not use from inside &v4l2_ctrl_ops. 694 */ 695 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id); 696 697 /** 698 * v4l2_ctrl_activate() - Make the control active or inactive. 699 * @ctrl: The control to (de)activate. 700 * @active: True if the control should become active. 701 * 702 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically. 703 * Does nothing if @ctrl == NULL. 704 * This will usually be called from within the s_ctrl op. 705 * The V4L2_EVENT_CTRL event will be generated afterwards. 706 * 707 * This function assumes that the control handler is locked. 708 */ 709 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); 710 711 /** 712 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed. 713 * 714 * @ctrl: The control to (de)activate. 715 * @grabbed: True if the control should become grabbed. 716 * 717 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically. 718 * Does nothing if @ctrl == NULL. 719 * The V4L2_EVENT_CTRL event will be generated afterwards. 720 * This will usually be called when starting or stopping streaming in the 721 * driver. 722 * 723 * This function assumes that the control handler is not locked and will 724 * take the lock itself. 725 */ 726 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); 727 728 /** 729 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range() 730 * 731 * @ctrl: The control to update. 732 * @min: The control's minimum value. 733 * @max: The control's maximum value. 734 * @step: The control's step value 735 * @def: The control's default value. 736 * 737 * Update the range of a control on the fly. This works for control types 738 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 739 * @step value is interpreted as a menu_skip_mask. 740 * 741 * An error is returned if one of the range arguments is invalid for this 742 * control type. 743 * 744 * This function assumes that the control handler is not locked and will 745 * take the lock itself. 746 */ 747 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 748 s64 min, s64 max, u64 step, s64 def); 749 750 /** 751 * v4l2_ctrl_modify_range() - Update the range of a control. 752 * 753 * @ctrl: The control to update. 754 * @min: The control's minimum value. 755 * @max: The control's maximum value. 756 * @step: The control's step value 757 * @def: The control's default value. 758 * 759 * Update the range of a control on the fly. This works for control types 760 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the 761 * @step value is interpreted as a menu_skip_mask. 762 * 763 * An error is returned if one of the range arguments is invalid for this 764 * control type. 765 * 766 * This function assumes that the control handler is not locked and will 767 * take the lock itself. 768 */ 769 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 770 s64 min, s64 max, u64 step, s64 def) 771 { 772 int rval; 773 774 v4l2_ctrl_lock(ctrl); 775 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def); 776 v4l2_ctrl_unlock(ctrl); 777 778 return rval; 779 } 780 781 /** 782 * v4l2_ctrl_notify() - Function to set a notify callback for a control. 783 * 784 * @ctrl: The control. 785 * @notify: The callback function. 786 * @priv: The callback private handle, passed as argument to the callback. 787 * 788 * This function sets a callback function for the control. If @ctrl is NULL, 789 * then it will do nothing. If @notify is NULL, then the notify callback will 790 * be removed. 791 * 792 * There can be only one notify. If another already exists, then a WARN_ON 793 * will be issued and the function will do nothing. 794 */ 795 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, 796 void *priv); 797 798 /** 799 * v4l2_ctrl_get_name() - Get the name of the control 800 * 801 * @id: The control ID. 802 * 803 * This function returns the name of the given control ID or NULL if it isn't 804 * a known control. 805 */ 806 const char *v4l2_ctrl_get_name(u32 id); 807 808 /** 809 * v4l2_ctrl_get_menu() - Get the menu string array of the control 810 * 811 * @id: The control ID. 812 * 813 * This function returns the NULL-terminated menu string array name of the 814 * given control ID or NULL if it isn't a known menu control. 815 */ 816 const char * const *v4l2_ctrl_get_menu(u32 id); 817 818 /** 819 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control 820 * 821 * @id: The control ID. 822 * @len: The size of the integer array. 823 * 824 * This function returns the integer array of the given control ID or NULL if it 825 * if it isn't a known integer menu control. 826 */ 827 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len); 828 829 /** 830 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from 831 * within a driver. 832 * 833 * @ctrl: The control. 834 * 835 * This returns the control's value safely by going through the control 836 * framework. This function will lock the control's handler, so it cannot be 837 * used from within the &v4l2_ctrl_ops functions. 838 * 839 * This function is for integer type controls only. 840 */ 841 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); 842 843 /** 844 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl(). 845 * 846 * @ctrl: The control. 847 * @val: TheControls name new value. 848 * 849 * This sets the control's new value safely by going through the control 850 * framework. This function assumes the control's handler is already locked, 851 * allowing it to be used from within the &v4l2_ctrl_ops functions. 852 * 853 * This function is for integer type controls only. 854 */ 855 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val); 856 857 /** 858 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from 859 * within a driver. 860 * @ctrl: The control. 861 * @val: The new value. 862 * 863 * This sets the control's new value safely by going through the control 864 * framework. This function will lock the control's handler, so it cannot be 865 * used from within the &v4l2_ctrl_ops functions. 866 * 867 * This function is for integer type controls only. 868 */ 869 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) 870 { 871 int rval; 872 873 v4l2_ctrl_lock(ctrl); 874 rval = __v4l2_ctrl_s_ctrl(ctrl, val); 875 v4l2_ctrl_unlock(ctrl); 876 877 return rval; 878 } 879 880 /** 881 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value 882 * from within a driver. 883 * 884 * @ctrl: The control. 885 * 886 * This returns the control's value safely by going through the control 887 * framework. This function will lock the control's handler, so it cannot be 888 * used from within the &v4l2_ctrl_ops functions. 889 * 890 * This function is for 64-bit integer type controls only. 891 */ 892 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl); 893 894 /** 895 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64(). 896 * 897 * @ctrl: The control. 898 * @val: The new value. 899 * 900 * This sets the control's new value safely by going through the control 901 * framework. This function assumes the control's handler is already locked, 902 * allowing it to be used from within the &v4l2_ctrl_ops functions. 903 * 904 * This function is for 64-bit integer type controls only. 905 */ 906 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val); 907 908 /** 909 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value 910 * from within a driver. 911 * 912 * @ctrl: The control. 913 * @val: The new value. 914 * 915 * This sets the control's new value safely by going through the control 916 * framework. This function will lock the control's handler, so it cannot be 917 * used from within the &v4l2_ctrl_ops functions. 918 * 919 * This function is for 64-bit integer type controls only. 920 */ 921 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) 922 { 923 int rval; 924 925 v4l2_ctrl_lock(ctrl); 926 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val); 927 v4l2_ctrl_unlock(ctrl); 928 929 return rval; 930 } 931 932 /** 933 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). 934 * 935 * @ctrl: The control. 936 * @s: The new string. 937 * 938 * This sets the control's new string safely by going through the control 939 * framework. This function assumes the control's handler is already locked, 940 * allowing it to be used from within the &v4l2_ctrl_ops functions. 941 * 942 * This function is for string type controls only. 943 */ 944 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s); 945 946 /** 947 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value 948 * from within a driver. 949 * 950 * @ctrl: The control. 951 * @s: The new string. 952 *Controls name 953 * This sets the control's new string safely by going through the control 954 * framework. This function will lock the control's handler, so it cannot be 955 * used from within the &v4l2_ctrl_ops functions. 956 * 957 * This function is for string type controls only. 958 */ 959 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s) 960 { 961 int rval; 962 963 v4l2_ctrl_lock(ctrl); 964 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s); 965 v4l2_ctrl_unlock(ctrl); 966 967 return rval; 968 } 969 970 /* Internal helper functions that deal with control events. */ 971 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops; 972 973 /** 974 * v4l2_ctrl_replace - Function to be used as a callback to 975 * &struct v4l2_subscribed_event_ops replace\(\) 976 * 977 * @old: pointer to struct &v4l2_event with the reported 978 * event; 979 * @new: pointer to struct &v4l2_event with the modified 980 * event; 981 */ 982 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new); 983 984 /** 985 * v4l2_ctrl_merge - Function to be used as a callback to 986 * &struct v4l2_subscribed_event_ops merge(\) 987 * 988 * @old: pointer to struct &v4l2_event with the reported 989 * event; 990 * @new: pointer to struct &v4l2_event with the merged 991 * event; 992 */ 993 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new); 994 995 /** 996 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl 997 * 998 * @file: pointer to struct file 999 * @fh: unused. Kept just to be compatible to the arguments expected by 1000 * &struct v4l2_ioctl_ops.vidioc_log_status. 1001 * 1002 * Can be used as a vidioc_log_status function that just dumps all controls 1003 * associated with the filehandle. 1004 */ 1005 int v4l2_ctrl_log_status(struct file *file, void *fh); 1006 1007 /** 1008 * v4l2_ctrl_subscribe_event - Subscribes to an event 1009 * 1010 * 1011 * @fh: pointer to struct v4l2_fh 1012 * @sub: pointer to &struct v4l2_event_subscription 1013 * 1014 * Can be used as a vidioc_subscribe_event function that just subscribes 1015 * control events. 1016 */ 1017 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, 1018 const struct v4l2_event_subscription *sub); 1019 1020 /** 1021 * v4l2_ctrl_poll - function to be used as a callback to the poll() 1022 * That just polls for control events. 1023 * 1024 * @file: pointer to struct file 1025 * @wait: pointer to struct poll_table_struct 1026 */ 1027 unsigned int v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); 1028 1029 /* Helpers for ioctl_ops */ 1030 1031 /** 1032 * v4l2_queryctrl - Helper function to implement 1033 * :ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl 1034 * 1035 * @hdl: pointer to &struct v4l2_ctrl_handler 1036 * @qc: pointer to &struct v4l2_queryctrl 1037 * 1038 * If hdl == NULL then they will all return -EINVAL. 1039 */ 1040 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc); 1041 1042 /** 1043 * v4l2_query_ext_ctrl - Helper function to implement 1044 * :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl 1045 * 1046 * @hdl: pointer to &struct v4l2_ctrl_handler 1047 * @qc: pointer to &struct v4l2_query_ext_ctrl 1048 * 1049 * If hdl == NULL then they will all return -EINVAL. 1050 */ 1051 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, 1052 struct v4l2_query_ext_ctrl *qc); 1053 1054 /** 1055 * v4l2_querymenu - Helper function to implement 1056 * :ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl 1057 * 1058 * @hdl: pointer to &struct v4l2_ctrl_handler 1059 * @qm: pointer to &struct v4l2_querymenu 1060 * 1061 * If hdl == NULL then they will all return -EINVAL. 1062 */ 1063 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm); 1064 1065 /** 1066 * v4l2_g_ctrl - Helper function to implement 1067 * :ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl 1068 * 1069 * @hdl: pointer to &struct v4l2_ctrl_handler 1070 * @ctrl: pointer to &struct v4l2_control 1071 * 1072 * If hdl == NULL then they will all return -EINVAL. 1073 */ 1074 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl); 1075 1076 /** 1077 * v4l2_s_ctrl - Helper function to implement 1078 * :ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl 1079 * 1080 * @fh: pointer to &struct v4l2_fh 1081 * @hdl: pointer to &struct v4l2_ctrl_handler 1082 * 1083 * @ctrl: pointer to &struct v4l2_control 1084 * 1085 * If hdl == NULL then they will all return -EINVAL. 1086 */ 1087 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1088 struct v4l2_control *ctrl); 1089 1090 /** 1091 * v4l2_g_ext_ctrls - Helper function to implement 1092 * :ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1093 * 1094 * @hdl: pointer to &struct v4l2_ctrl_handler 1095 * @c: pointer to &struct v4l2_ext_controls 1096 * 1097 * If hdl == NULL then they will all return -EINVAL. 1098 */ 1099 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1100 struct v4l2_ext_controls *c); 1101 1102 /** 1103 * v4l2_try_ext_ctrls - Helper function to implement 1104 * :ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1105 * 1106 * @hdl: pointer to &struct v4l2_ctrl_handler 1107 * @c: pointer to &struct v4l2_ext_controls 1108 * 1109 * If hdl == NULL then they will all return -EINVAL. 1110 */ 1111 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, 1112 struct v4l2_ext_controls *c); 1113 1114 /** 1115 * v4l2_s_ext_ctrls - Helper function to implement 1116 * :ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl 1117 * 1118 * @fh: pointer to &struct v4l2_fh 1119 * @hdl: pointer to &struct v4l2_ctrl_handler 1120 * @c: pointer to &struct v4l2_ext_controls 1121 * 1122 * If hdl == NULL then they will all return -EINVAL. 1123 */ 1124 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, 1125 struct v4l2_ext_controls *c); 1126 1127 /** 1128 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement 1129 * as a &struct v4l2_subdev_core_ops subscribe_event function 1130 * that just subscribes control events. 1131 * 1132 * @sd: pointer to &struct v4l2_subdev 1133 * @fh: pointer to &struct v4l2_fh 1134 * @sub: pointer to &struct v4l2_event_subscription 1135 */ 1136 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh, 1137 struct v4l2_event_subscription *sub); 1138 1139 /** 1140 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control 1141 * handler. 1142 * 1143 * @sd: pointer to &struct v4l2_subdev 1144 */ 1145 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd); 1146 1147 #endif 1148