1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * V4L2 controls support header.
5 * Copyright (C) 2010 Hans Verkuil <hverkuil@xs4all.nl>
11 #include <linux/list.h>
12 #include <linux/mutex.h>
13 #include <linux/videodev2.h>
14 #include <media/media-request.h>
17 * Include the stateless codec compound control definitions.
18 * This will move to the public headers once this API is fully stable.
20 #include <media/mpeg2-ctrls.h>
21 #include <media/fwht-ctrls.h>
22 #include <media/h264-ctrls.h>
23 #include <media/vp8-ctrls.h>
24 #include <media/hevc-ctrls.h>
26 /* forward references */
28 struct poll_table_struct;
30 struct v4l2_ctrl_handler;
31 struct v4l2_ctrl_helper;
33 struct v4l2_fwnode_device_properties;
35 struct v4l2_subscribed_event;
39 * union v4l2_ctrl_ptr - A pointer to a control value.
40 * @p_s32: Pointer to a 32-bit signed value.
41 * @p_s64: Pointer to a 64-bit signed value.
42 * @p_u8: Pointer to a 8-bit unsigned value.
43 * @p_u16: Pointer to a 16-bit unsigned value.
44 * @p_u32: Pointer to a 32-bit unsigned value.
45 * @p_char: Pointer to a string.
46 * @p_mpeg2_slice_params: Pointer to a MPEG2 slice parameters structure.
47 * @p_mpeg2_quantization: Pointer to a MPEG2 quantization data structure.
48 * @p_fwht_params: Pointer to a FWHT stateless parameters structure.
49 * @p_h264_sps: Pointer to a struct v4l2_ctrl_h264_sps.
50 * @p_h264_pps: Pointer to a struct v4l2_ctrl_h264_pps.
51 * @p_h264_scaling_matrix: Pointer to a struct v4l2_ctrl_h264_scaling_matrix.
52 * @p_h264_slice_params: Pointer to a struct v4l2_ctrl_h264_slice_params.
53 * @p_h264_decode_params: Pointer to a struct v4l2_ctrl_h264_decode_params.
54 * @p_h264_pred_weights: Pointer to a struct v4l2_ctrl_h264_pred_weights.
55 * @p_vp8_frame_header: Pointer to a VP8 frame header structure.
56 * @p_hevc_sps: Pointer to an HEVC sequence parameter set structure.
57 * @p_hevc_pps: Pointer to an HEVC picture parameter set structure.
58 * @p_hevc_slice_params: Pointer to an HEVC slice parameters structure.
59 * @p_area: Pointer to an area.
60 * @p: Pointer to a compound value.
61 * @p_const: Pointer to a constant compound value.
70 struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
71 struct v4l2_ctrl_mpeg2_quantization *p_mpeg2_quantization;
72 struct v4l2_ctrl_fwht_params *p_fwht_params;
73 struct v4l2_ctrl_h264_sps *p_h264_sps;
74 struct v4l2_ctrl_h264_pps *p_h264_pps;
75 struct v4l2_ctrl_h264_scaling_matrix *p_h264_scaling_matrix;
76 struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
77 struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
78 struct v4l2_ctrl_h264_pred_weights *p_h264_pred_weights;
79 struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
80 struct v4l2_ctrl_hevc_sps *p_hevc_sps;
81 struct v4l2_ctrl_hevc_pps *p_hevc_pps;
82 struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
83 struct v4l2_area *p_area;
89 * v4l2_ctrl_ptr_create() - Helper function to return a v4l2_ctrl_ptr from a
91 * @ptr: The void pointer
93 static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_create(void *ptr)
95 union v4l2_ctrl_ptr p = { .p = ptr };
101 * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
103 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
104 * for volatile (and usually read-only) controls such as a control
105 * that returns the current signal strength which changes
107 * If not set, then the currently cached value will be returned.
108 * @try_ctrl: Test whether the control's value is valid. Only relevant when
109 * the usual min/max/step checks are not sufficient.
110 * @s_ctrl: Actually set the new control value. s_ctrl is compulsory. The
111 * ctrl->handler->lock is held when these ops are called, so no
112 * one else can access controls owned by that handler.
114 struct v4l2_ctrl_ops {
115 int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
116 int (*try_ctrl)(struct v4l2_ctrl *ctrl);
117 int (*s_ctrl)(struct v4l2_ctrl *ctrl);
121 * struct v4l2_ctrl_type_ops - The control type operations that the driver
124 * @equal: return true if both values are equal.
125 * @init: initialize the value.
126 * @log: log the value.
127 * @validate: validate the value. Return 0 on success and a negative value
130 struct v4l2_ctrl_type_ops {
131 bool (*equal)(const struct v4l2_ctrl *ctrl, u32 idx,
132 union v4l2_ctrl_ptr ptr1,
133 union v4l2_ctrl_ptr ptr2);
134 void (*init)(const struct v4l2_ctrl *ctrl, u32 idx,
135 union v4l2_ctrl_ptr ptr);
136 void (*log)(const struct v4l2_ctrl *ctrl);
137 int (*validate)(const struct v4l2_ctrl *ctrl, u32 idx,
138 union v4l2_ctrl_ptr ptr);
142 * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
143 * that should be called when a control value has changed.
145 * @ctrl: pointer to struct &v4l2_ctrl
146 * @priv: control private data
148 * This typedef definition is used as an argument to v4l2_ctrl_notify()
149 * and as an argument at struct &v4l2_ctrl_handler.
151 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
154 * struct v4l2_ctrl - The control structure.
156 * @node: The list node.
157 * @ev_subs: The list of control event subscriptions.
158 * @handler: The handler that owns the control.
159 * @cluster: Point to start of cluster array.
160 * @ncontrols: Number of controls in cluster array.
161 * @done: Internal flag: set for each processed control.
162 * @is_new: Set when the user specified a new value for this control. It
163 * is also set when called from v4l2_ctrl_handler_setup(). Drivers
164 * should never set this flag.
165 * @has_changed: Set when the current value differs from the new value. Drivers
166 * should never use this flag.
167 * @is_private: If set, then this control is private to its handler and it
168 * will not be added to any other handlers. Drivers can set
170 * @is_auto: If set, then this control selects whether the other cluster
171 * members are in 'automatic' mode or 'manual' mode. This is
172 * used for autogain/gain type clusters. Drivers should never
173 * set this flag directly.
174 * @is_int: If set, then this control has a simple integer value (i.e. it
176 * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
177 * @is_ptr: If set, then this control is an array and/or has type >=
178 * %V4L2_CTRL_COMPOUND_TYPES
179 * and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
180 * v4l2_ext_control uses field p to point to the data.
181 * @is_array: If set, then this control contains an N-dimensional array.
182 * @has_volatiles: If set, then one or more members of the cluster are volatile.
183 * Drivers should never touch this flag.
184 * @call_notify: If set, then call the handler's notify function whenever the
185 * control's value changes.
186 * @manual_mode_value: If the is_auto flag is set, then this is the value
187 * of the auto control that determines if that control is in
188 * manual mode. So if the value of the auto control equals this
189 * value, then the whole cluster is in manual mode. Drivers should
190 * never set this flag directly.
191 * @ops: The control ops.
192 * @type_ops: The control type ops.
193 * @id: The control ID.
194 * @name: The control name.
195 * @type: The control type.
196 * @minimum: The control's minimum value.
197 * @maximum: The control's maximum value.
198 * @default_value: The control's default value.
199 * @step: The control's step value for non-menu controls.
200 * @elems: The number of elements in the N-dimensional array.
201 * @elem_size: The size in bytes of the control.
202 * @dims: The size of each dimension.
203 * @nr_of_dims:The number of dimensions in @dims.
204 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
205 * easy to skip menu items that are not valid. If bit X is set,
206 * then menu item X is skipped. Of course, this only works for
207 * menus with <= 32 menu items. There are no menus that come
208 * close to that number, so this is OK. Should we ever need more,
209 * then this will have to be extended to a u64 or a bit array.
210 * @qmenu: A const char * array for all menu items. Array entries that are
211 * empty strings ("") correspond to non-existing menu items (this
212 * is in addition to the menu_skip_mask above). The last entry
214 * Used only if the @type is %V4L2_CTRL_TYPE_MENU.
215 * @qmenu_int: A 64-bit integer array for with integer menu items.
216 * The size of array must be equal to the menu size, e. g.:
217 * :math:`ceil(\frac{maximum - minimum}{step}) + 1`.
218 * Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
219 * @flags: The control's flags.
220 * @cur: Structure to store the current value.
221 * @cur.val: The control's current value, if the @type is represented via
222 * a u32 integer (see &enum v4l2_ctrl_type).
223 * @val: The control's new s32 value.
224 * @priv: The control's private pointer. For use by the driver. It is
225 * untouched by the control framework. Note that this pointer is
226 * not freed when the control is deleted. Should this be needed
227 * then a new internal bitfield can be added to tell the framework
228 * to free this pointer.
229 * @p_def: The control's default value represented via a union which
230 * provides a standard way of accessing control types
231 * through a pointer (for compound controls only).
232 * @p_cur: The control's current value represented via a union which
233 * provides a standard way of accessing control types
235 * @p_new: The control's new value represented via a union which provides
236 * a standard way of accessing control types
240 /* Administrative fields */
241 struct list_head node;
242 struct list_head ev_subs;
243 struct v4l2_ctrl_handler *handler;
244 struct v4l2_ctrl **cluster;
245 unsigned int ncontrols;
249 unsigned int is_new:1;
250 unsigned int has_changed:1;
251 unsigned int is_private:1;
252 unsigned int is_auto:1;
253 unsigned int is_int:1;
254 unsigned int is_string:1;
255 unsigned int is_ptr:1;
256 unsigned int is_array:1;
257 unsigned int has_volatiles:1;
258 unsigned int call_notify:1;
259 unsigned int manual_mode_value:8;
261 const struct v4l2_ctrl_ops *ops;
262 const struct v4l2_ctrl_type_ops *type_ops;
265 enum v4l2_ctrl_type type;
266 s64 minimum, maximum, default_value;
269 u32 dims[V4L2_CTRL_MAX_DIMS];
276 const char * const *qmenu;
277 const s64 *qmenu_int;
286 union v4l2_ctrl_ptr p_def;
287 union v4l2_ctrl_ptr p_new;
288 union v4l2_ctrl_ptr p_cur;
292 * struct v4l2_ctrl_ref - The control reference.
294 * @node: List node for the sorted list.
295 * @next: Single-link list node for the hash.
296 * @ctrl: The actual control information.
297 * @helper: Pointer to helper struct. Used internally in
298 * ``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
299 * @from_other_dev: If true, then @ctrl was defined in another
300 * device than the &struct v4l2_ctrl_handler.
301 * @req_done: Internal flag: if the control handler containing this control
302 * reference is bound to a media request, then this is set when
303 * the control has been applied. This prevents applying controls
304 * from a cluster with multiple controls twice (when the first
305 * control of a cluster is applied, they all are).
306 * @req: If set, this refers to another request that sets this control.
307 * @p_req: If the control handler containing this control reference
308 * is bound to a media request, then this points to the
309 * value of the control that should be applied when the request
310 * is executed, or to the value of the control at the time
311 * that the request was completed.
313 * Each control handler has a list of these refs. The list_head is used to
314 * keep a sorted-by-control-ID list of all controls, while the next pointer
315 * is used to link the control in the hash's bucket.
317 struct v4l2_ctrl_ref {
318 struct list_head node;
319 struct v4l2_ctrl_ref *next;
320 struct v4l2_ctrl *ctrl;
321 struct v4l2_ctrl_helper *helper;
324 struct v4l2_ctrl_ref *req;
325 union v4l2_ctrl_ptr p_req;
329 * struct v4l2_ctrl_handler - The control handler keeps track of all the
330 * controls: both the controls owned by the handler and those inherited
331 * from other handlers.
333 * @_lock: Default for "lock".
334 * @lock: Lock to control access to this handler and its controls.
335 * May be replaced by the user right after init.
336 * @ctrls: The list of controls owned by this handler.
337 * @ctrl_refs: The list of control references.
338 * @cached: The last found control reference. It is common that the same
339 * control is needed multiple times, so this is a simple
341 * @buckets: Buckets for the hashing. Allows for quick control lookup.
342 * @notify: A notify callback that is called whenever the control changes
344 * Note that the handler's lock is held when the notify function
346 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
347 * @nr_of_buckets: Total number of buckets in the array.
348 * @error: The error code of the first failed control addition.
349 * @request_is_queued: True if the request was queued.
350 * @requests: List to keep track of open control handler request objects.
351 * For the parent control handler (@req_obj.req == NULL) this
352 * is the list header. When the parent control handler is
353 * removed, it has to unbind and put all these requests since
354 * they refer to the parent.
355 * @requests_queued: List of the queued requests. This determines the order
356 * in which these controls are applied. Once the request is
357 * completed it is removed from this list.
358 * @req_obj: The &struct media_request_object, used to link into a
359 * &struct media_request. This request object has a refcount.
361 struct v4l2_ctrl_handler {
364 struct list_head ctrls;
365 struct list_head ctrl_refs;
366 struct v4l2_ctrl_ref *cached;
367 struct v4l2_ctrl_ref **buckets;
368 v4l2_ctrl_notify_fnc notify;
372 bool request_is_queued;
373 struct list_head requests;
374 struct list_head requests_queued;
375 struct media_request_object req_obj;
379 * struct v4l2_ctrl_config - Control configuration structure.
381 * @ops: The control ops.
382 * @type_ops: The control type ops. Only needed for compound controls.
383 * @id: The control ID.
384 * @name: The control name.
385 * @type: The control type.
386 * @min: The control's minimum value.
387 * @max: The control's maximum value.
388 * @step: The control's step value for non-menu controls.
389 * @def: The control's default value.
390 * @p_def: The control's default value for compound controls.
391 * @dims: The size of each dimension.
392 * @elem_size: The size in bytes of the control.
393 * @flags: The control's flags.
394 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
395 * easy to skip menu items that are not valid. If bit X is set,
396 * then menu item X is skipped. Of course, this only works for
397 * menus with <= 64 menu items. There are no menus that come
398 * close to that number, so this is OK. Should we ever need more,
399 * then this will have to be extended to a bit array.
400 * @qmenu: A const char * array for all menu items. Array entries that are
401 * empty strings ("") correspond to non-existing menu items (this
402 * is in addition to the menu_skip_mask above). The last entry
404 * @qmenu_int: A const s64 integer array for all menu items of the type
405 * V4L2_CTRL_TYPE_INTEGER_MENU.
406 * @is_private: If set, then this control is private to its handler and it
407 * will not be added to any other handlers.
409 struct v4l2_ctrl_config {
410 const struct v4l2_ctrl_ops *ops;
411 const struct v4l2_ctrl_type_ops *type_ops;
414 enum v4l2_ctrl_type type;
419 union v4l2_ctrl_ptr p_def;
420 u32 dims[V4L2_CTRL_MAX_DIMS];
424 const char * const *qmenu;
425 const s64 *qmenu_int;
426 unsigned int is_private:1;
430 * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
432 * @id: ID of the control
433 * @name: pointer to be filled with a string with the name of the control
434 * @type: pointer for storing the type of the control
435 * @min: pointer for storing the minimum value for the control
436 * @max: pointer for storing the maximum value for the control
437 * @step: pointer for storing the control step
438 * @def: pointer for storing the default value for the control
439 * @flags: pointer for storing the flags to be used on the control
441 * This works for all standard V4L2 controls.
442 * For non-standard controls it will only fill in the given arguments
443 * and @name content will be set to %NULL.
445 * This function will overwrite the contents of @name, @type and @flags.
446 * The contents of @min, @max, @step and @def may be modified depending on
451 * Do not use in drivers! It is used internally for backwards compatibility
452 * control handling only. Once all drivers are converted to use the new
453 * control framework this function will no longer be exported.
455 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
456 s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
460 * v4l2_ctrl_handler_init_class() - Initialize the control handler.
461 * @hdl: The control handler.
462 * @nr_of_controls_hint: A hint of how many controls this handler is
463 * expected to refer to. This is the total number, so including
464 * any inherited controls. It doesn't have to be precise, but if
465 * it is way off, then you either waste memory (too many buckets
466 * are allocated) or the control lookup becomes slower (not enough
467 * buckets are allocated, so there are more slow list lookups).
468 * It will always work, though.
469 * @key: Used by the lock validator if CONFIG_LOCKDEP is set.
470 * @name: Used by the lock validator if CONFIG_LOCKDEP is set.
474 * Never use this call directly, always use the v4l2_ctrl_handler_init()
475 * macro that hides the @key and @name arguments.
477 * Return: returns an error if the buckets could not be allocated. This
478 * error will also be stored in @hdl->error.
480 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
481 unsigned int nr_of_controls_hint,
482 struct lock_class_key *key, const char *name);
484 #ifdef CONFIG_LOCKDEP
487 * v4l2_ctrl_handler_init - helper function to create a static struct
488 * &lock_class_key and calls v4l2_ctrl_handler_init_class()
490 * @hdl: The control handler.
491 * @nr_of_controls_hint: A hint of how many controls this handler is
492 * expected to refer to. This is the total number, so including
493 * any inherited controls. It doesn't have to be precise, but if
494 * it is way off, then you either waste memory (too many buckets
495 * are allocated) or the control lookup becomes slower (not enough
496 * buckets are allocated, so there are more slow list lookups).
497 * It will always work, though.
499 * This helper function creates a static struct &lock_class_key and
500 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
503 * Use this helper function to initialize a control handler.
505 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \
508 static struct lock_class_key _key; \
509 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \
511 KBUILD_BASENAME ":" \
512 __stringify(__LINE__) ":" \
513 "(" #hdl ")->_lock"); \
517 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \
518 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
522 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
524 * @hdl: The control handler.
526 * Does nothing if @hdl == NULL.
528 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
531 * v4l2_ctrl_lock() - Helper function to lock the handler
532 * associated with the control.
533 * @ctrl: The control to lock.
535 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
537 mutex_lock(ctrl->handler->lock);
541 * v4l2_ctrl_unlock() - Helper function to unlock the handler
542 * associated with the control.
543 * @ctrl: The control to unlock.
545 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
547 mutex_unlock(ctrl->handler->lock);
551 * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
552 * to the handler to initialize the hardware to the current control values. The
553 * caller is responsible for acquiring the control handler mutex on behalf of
554 * __v4l2_ctrl_handler_setup().
555 * @hdl: The control handler.
557 * Button controls will be skipped, as are read-only controls.
559 * If @hdl == NULL, then this just returns 0.
561 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
564 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
565 * to the handler to initialize the hardware to the current control values.
566 * @hdl: The control handler.
568 * Button controls will be skipped, as are read-only controls.
570 * If @hdl == NULL, then this just returns 0.
572 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
575 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
576 * @hdl: The control handler.
577 * @prefix: The prefix to use when logging the control values. If the
578 * prefix does not end with a space, then ": " will be added
579 * after the prefix. If @prefix == NULL, then no prefix will be
582 * For use with VIDIOC_LOG_STATUS.
584 * Does nothing if @hdl == NULL.
586 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
590 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
593 * @hdl: The control handler.
594 * @cfg: The control's configuration data.
595 * @priv: The control's driver-specific private data.
597 * If the &v4l2_ctrl struct could not be allocated then NULL is returned
598 * and @hdl->error is set to the error code (if it wasn't set already).
600 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
601 const struct v4l2_ctrl_config *cfg,
605 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
608 * @hdl: The control handler.
609 * @ops: The control ops.
610 * @id: The control ID.
611 * @min: The control's minimum value.
612 * @max: The control's maximum value.
613 * @step: The control's step value
614 * @def: The control's default value.
616 * If the &v4l2_ctrl struct could not be allocated, or the control
617 * ID is not known, then NULL is returned and @hdl->error is set to the
618 * appropriate error code (if it wasn't set already).
620 * If @id refers to a menu control, then this function will return NULL.
622 * Use v4l2_ctrl_new_std_menu() when adding menu controls.
624 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
625 const struct v4l2_ctrl_ops *ops,
626 u32 id, s64 min, s64 max, u64 step,
630 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
633 * @hdl: The control handler.
634 * @ops: The control ops.
635 * @id: The control ID.
636 * @max: The control's maximum value.
637 * @mask: The control's skip mask for menu controls. This makes it
638 * easy to skip menu items that are not valid. If bit X is set,
639 * then menu item X is skipped. Of course, this only works for
640 * menus with <= 64 menu items. There are no menus that come
641 * close to that number, so this is OK. Should we ever need more,
642 * then this will have to be extended to a bit array.
643 * @def: The control's default value.
645 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
646 * determines which menu items are to be skipped.
648 * If @id refers to a non-menu control, then this function will return NULL.
650 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
651 const struct v4l2_ctrl_ops *ops,
652 u32 id, u8 max, u64 mask, u8 def);
655 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
656 * with driver specific menu.
658 * @hdl: The control handler.
659 * @ops: The control ops.
660 * @id: The control ID.
661 * @max: The control's maximum value.
662 * @mask: The control's skip mask for menu controls. This makes it
663 * easy to skip menu items that are not valid. If bit X is set,
664 * then menu item X is skipped. Of course, this only works for
665 * menus with <= 64 menu items. There are no menus that come
666 * close to that number, so this is OK. Should we ever need more,
667 * then this will have to be extended to a bit array.
668 * @def: The control's default value.
669 * @qmenu: The new menu.
671 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
672 * menu of this control.
675 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
676 const struct v4l2_ctrl_ops *ops,
679 const char * const *qmenu);
682 * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
685 * @hdl: The control handler.
686 * @ops: The control ops.
687 * @id: The control ID.
688 * @p_def: The control's default value.
690 * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
691 * to the @p_def field. Use v4l2_ctrl_ptr_create() to create @p_def from a
692 * pointer. Use v4l2_ctrl_ptr_create(NULL) if the default value of the
693 * compound control should be all zeroes.
696 struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
697 const struct v4l2_ctrl_ops *ops,
699 const union v4l2_ctrl_ptr p_def);
702 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
704 * @hdl: The control handler.
705 * @ops: The control ops.
706 * @id: The control ID.
707 * @max: The control's maximum value.
708 * @def: The control's default value.
709 * @qmenu_int: The control's menu entries.
711 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
712 * takes as an argument an array of integers determining the menu items.
714 * If @id refers to a non-integer-menu control, then this function will
717 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
718 const struct v4l2_ctrl_ops *ops,
719 u32 id, u8 max, u8 def,
720 const s64 *qmenu_int);
723 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
724 * used when adding a control handler.
726 * @ctrl: pointer to struct &v4l2_ctrl.
729 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
732 * v4l2_ctrl_add_handler() - Add all controls from handler @add to
735 * @hdl: The control handler.
736 * @add: The control handler whose controls you want to add to
737 * the @hdl control handler.
738 * @filter: This function will filter which controls should be added.
739 * @from_other_dev: If true, then the controls in @add were defined in another
742 * Does nothing if either of the two handlers is a NULL pointer.
743 * If @filter is NULL, then all controls are added. Otherwise only those
744 * controls for which @filter returns true will be added.
745 * In case of an error @hdl->error will be set to the error code (if it
746 * wasn't set already).
748 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
749 struct v4l2_ctrl_handler *add,
750 v4l2_ctrl_filter filter,
751 bool from_other_dev);
754 * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
756 * @ctrl: The control that is filtered.
758 * This will return true for any controls that are valid for radio device
759 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
760 * transmitter class controls.
762 * This function is to be used with v4l2_ctrl_add_handler().
764 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
767 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
770 * @ncontrols: The number of controls in this cluster.
771 * @controls: The cluster control array of size @ncontrols.
773 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
777 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
778 * to that cluster and set it up for autofoo/foo-type handling.
780 * @ncontrols: The number of controls in this cluster.
781 * @controls: The cluster control array of size @ncontrols. The first control
782 * must be the 'auto' control (e.g. autogain, autoexposure, etc.)
783 * @manual_val: The value for the first control in the cluster that equals the
785 * @set_volatile: If true, then all controls except the first auto control will
788 * Use for control groups where one control selects some automatic feature and
789 * the other controls are only active whenever the automatic feature is turned
790 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
791 * red and blue balance, etc.
793 * The behavior of such controls is as follows:
795 * When the autofoo control is set to automatic, then any manual controls
796 * are set to inactive and any reads will call g_volatile_ctrl (if the control
797 * was marked volatile).
799 * When the autofoo control is set to manual, then any manual controls will
800 * be marked active, and any reads will just return the current value without
801 * going through g_volatile_ctrl.
803 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
804 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
805 * if autofoo is in auto mode.
807 void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
808 struct v4l2_ctrl **controls,
809 u8 manual_val, bool set_volatile);
813 * v4l2_ctrl_find() - Find a control with the given ID.
815 * @hdl: The control handler.
816 * @id: The control ID to find.
818 * If @hdl == NULL this will return NULL as well. Will lock the handler so
819 * do not use from inside &v4l2_ctrl_ops.
821 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
824 * v4l2_ctrl_activate() - Make the control active or inactive.
825 * @ctrl: The control to (de)activate.
826 * @active: True if the control should become active.
828 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
829 * Does nothing if @ctrl == NULL.
830 * This will usually be called from within the s_ctrl op.
831 * The V4L2_EVENT_CTRL event will be generated afterwards.
833 * This function assumes that the control handler is locked.
835 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
838 * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
840 * @ctrl: The control to (de)activate.
841 * @grabbed: True if the control should become grabbed.
843 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
844 * Does nothing if @ctrl == NULL.
845 * The V4L2_EVENT_CTRL event will be generated afterwards.
846 * This will usually be called when starting or stopping streaming in the
849 * This function assumes that the control handler is locked by the caller.
851 void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
854 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
856 * @ctrl: The control to (de)activate.
857 * @grabbed: True if the control should become grabbed.
859 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
860 * Does nothing if @ctrl == NULL.
861 * The V4L2_EVENT_CTRL event will be generated afterwards.
862 * This will usually be called when starting or stopping streaming in the
865 * This function assumes that the control handler is not locked and will
866 * take the lock itself.
868 static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
873 v4l2_ctrl_lock(ctrl);
874 __v4l2_ctrl_grab(ctrl, grabbed);
875 v4l2_ctrl_unlock(ctrl);
879 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
881 * @ctrl: The control to update.
882 * @min: The control's minimum value.
883 * @max: The control's maximum value.
884 * @step: The control's step value
885 * @def: The control's default value.
887 * Update the range of a control on the fly. This works for control types
888 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
889 * @step value is interpreted as a menu_skip_mask.
891 * An error is returned if one of the range arguments is invalid for this
894 * The caller is responsible for acquiring the control handler mutex on behalf
895 * of __v4l2_ctrl_modify_range().
897 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
898 s64 min, s64 max, u64 step, s64 def);
901 * v4l2_ctrl_modify_range() - Update the range of a control.
903 * @ctrl: The control to update.
904 * @min: The control's minimum value.
905 * @max: The control's maximum value.
906 * @step: The control's step value
907 * @def: The control's default value.
909 * Update the range of a control on the fly. This works for control types
910 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
911 * @step value is interpreted as a menu_skip_mask.
913 * An error is returned if one of the range arguments is invalid for this
916 * This function assumes that the control handler is not locked and will
917 * take the lock itself.
919 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
920 s64 min, s64 max, u64 step, s64 def)
924 v4l2_ctrl_lock(ctrl);
925 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
926 v4l2_ctrl_unlock(ctrl);
932 * v4l2_ctrl_notify() - Function to set a notify callback for a control.
934 * @ctrl: The control.
935 * @notify: The callback function.
936 * @priv: The callback private handle, passed as argument to the callback.
938 * This function sets a callback function for the control. If @ctrl is NULL,
939 * then it will do nothing. If @notify is NULL, then the notify callback will
942 * There can be only one notify. If another already exists, then a WARN_ON
943 * will be issued and the function will do nothing.
945 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
949 * v4l2_ctrl_get_name() - Get the name of the control
951 * @id: The control ID.
953 * This function returns the name of the given control ID or NULL if it isn't
956 const char *v4l2_ctrl_get_name(u32 id);
959 * v4l2_ctrl_get_menu() - Get the menu string array of the control
961 * @id: The control ID.
963 * This function returns the NULL-terminated menu string array name of the
964 * given control ID or NULL if it isn't a known menu control.
966 const char * const *v4l2_ctrl_get_menu(u32 id);
969 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
971 * @id: The control ID.
972 * @len: The size of the integer array.
974 * This function returns the integer array of the given control ID or NULL if it
975 * if it isn't a known integer menu control.
977 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
980 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
983 * @ctrl: The control.
985 * This returns the control's value safely by going through the control
986 * framework. This function will lock the control's handler, so it cannot be
987 * used from within the &v4l2_ctrl_ops functions.
989 * This function is for integer type controls only.
991 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
994 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
996 * @ctrl: The control.
997 * @val: The new value.
999 * This sets the control's new value safely by going through the control
1000 * framework. This function assumes the control's handler is already locked,
1001 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1003 * This function is for integer type controls only.
1005 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1008 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1010 * @ctrl: The control.
1011 * @val: The new value.
1013 * This sets the control's new value safely by going through the control
1014 * framework. This function will lock the control's handler, so it cannot be
1015 * used from within the &v4l2_ctrl_ops functions.
1017 * This function is for integer type controls only.
1019 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1023 v4l2_ctrl_lock(ctrl);
1024 rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1025 v4l2_ctrl_unlock(ctrl);
1031 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1032 * from within a driver.
1034 * @ctrl: The control.
1036 * This returns the control's value safely by going through the control
1037 * framework. This function will lock the control's handler, so it cannot be
1038 * used from within the &v4l2_ctrl_ops functions.
1040 * This function is for 64-bit integer type controls only.
1042 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1045 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1047 * @ctrl: The control.
1048 * @val: The new value.
1050 * This sets the control's new value safely by going through the control
1051 * framework. This function assumes the control's handler is already locked,
1052 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1054 * This function is for 64-bit integer type controls only.
1056 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1059 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1060 * from within a driver.
1062 * @ctrl: The control.
1063 * @val: The new value.
1065 * This sets the control's new value safely by going through the control
1066 * framework. This function will lock the control's handler, so it cannot be
1067 * used from within the &v4l2_ctrl_ops functions.
1069 * This function is for 64-bit integer type controls only.
1071 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1075 v4l2_ctrl_lock(ctrl);
1076 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1077 v4l2_ctrl_unlock(ctrl);
1083 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1085 * @ctrl: The control.
1086 * @s: The new string.
1088 * This sets the control's new string safely by going through the control
1089 * framework. This function assumes the control's handler is already locked,
1090 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1092 * This function is for string type controls only.
1094 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1097 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1098 * from within a driver.
1100 * @ctrl: The control.
1101 * @s: The new string.
1103 * This sets the control's new string safely by going through the control
1104 * framework. This function will lock the control's handler, so it cannot be
1105 * used from within the &v4l2_ctrl_ops functions.
1107 * This function is for string type controls only.
1109 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1113 v4l2_ctrl_lock(ctrl);
1114 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1115 v4l2_ctrl_unlock(ctrl);
1121 * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1123 * @ctrl: The control.
1124 * @type: The type of the data.
1125 * @p: The new compound payload.
1127 * This sets the control's new compound payload safely by going through the
1128 * control framework. This function assumes the control's handler is already
1129 * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1131 * This function is for compound type controls only.
1133 int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1134 enum v4l2_ctrl_type type, const void *p);
1137 * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1138 * from within a driver.
1140 * @ctrl: The control.
1141 * @type: The type of the data.
1142 * @p: The new compound payload.
1144 * This sets the control's new compound payload safely by going through the
1145 * control framework. This function will lock the control's handler, so it
1146 * cannot be used from within the &v4l2_ctrl_ops functions.
1148 * This function is for compound type controls only.
1150 static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1151 enum v4l2_ctrl_type type,
1156 v4l2_ctrl_lock(ctrl);
1157 rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1158 v4l2_ctrl_unlock(ctrl);
1163 /* Helper defines for area type controls */
1164 #define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1165 __v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1166 #define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1167 v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1169 /* Internal helper functions that deal with control events. */
1170 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1173 * v4l2_ctrl_replace - Function to be used as a callback to
1174 * &struct v4l2_subscribed_event_ops replace\(\)
1176 * @old: pointer to struct &v4l2_event with the reported
1178 * @new: pointer to struct &v4l2_event with the modified
1181 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1184 * v4l2_ctrl_merge - Function to be used as a callback to
1185 * &struct v4l2_subscribed_event_ops merge(\)
1187 * @old: pointer to struct &v4l2_event with the reported
1189 * @new: pointer to struct &v4l2_event with the merged
1192 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1195 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1197 * @file: pointer to struct file
1198 * @fh: unused. Kept just to be compatible to the arguments expected by
1199 * &struct v4l2_ioctl_ops.vidioc_log_status.
1201 * Can be used as a vidioc_log_status function that just dumps all controls
1202 * associated with the filehandle.
1204 int v4l2_ctrl_log_status(struct file *file, void *fh);
1207 * v4l2_ctrl_subscribe_event - Subscribes to an event
1210 * @fh: pointer to struct v4l2_fh
1211 * @sub: pointer to &struct v4l2_event_subscription
1213 * Can be used as a vidioc_subscribe_event function that just subscribes
1216 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1217 const struct v4l2_event_subscription *sub);
1220 * v4l2_ctrl_poll - function to be used as a callback to the poll()
1221 * That just polls for control events.
1223 * @file: pointer to struct file
1224 * @wait: pointer to struct poll_table_struct
1226 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1229 * v4l2_ctrl_request_setup - helper function to apply control values in a request
1232 * @parent: The parent control handler ('priv' in media_request_object_find())
1234 * This is a helper function to call the control handler's s_ctrl callback with
1235 * the control values contained in the request. Do note that this approach of
1236 * applying control values in a request is only applicable to memory-to-memory
1239 int v4l2_ctrl_request_setup(struct media_request *req,
1240 struct v4l2_ctrl_handler *parent);
1243 * v4l2_ctrl_request_complete - Complete a control handler request object
1246 * @parent: The parent control handler ('priv' in media_request_object_find())
1248 * This function is to be called on each control handler that may have had a
1249 * request object associated with it, i.e. control handlers of a driver that
1250 * supports requests.
1252 * The function first obtains the values of any volatile controls in the control
1253 * handler and attach them to the request. Then, the function completes the
1256 void v4l2_ctrl_request_complete(struct media_request *req,
1257 struct v4l2_ctrl_handler *parent);
1260 * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1263 * @parent: The parent control handler ('priv' in media_request_object_find())
1265 * This function finds the control handler in the request. It may return
1266 * NULL if not found. When done, you must call v4l2_ctrl_request_put_hdl()
1267 * with the returned handler pointer.
1269 * If the request is not in state VALIDATING or QUEUED, then this function
1270 * will always return NULL.
1272 * Note that in state VALIDATING the req_queue_mutex is held, so
1273 * no objects can be added or deleted from the request.
1275 * In state QUEUED it is the driver that will have to ensure this.
1277 struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1278 struct v4l2_ctrl_handler *parent);
1281 * v4l2_ctrl_request_hdl_put - Put the control handler
1283 * @hdl: Put this control handler
1285 * This function released the control handler previously obtained from'
1286 * v4l2_ctrl_request_hdl_find().
1288 static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1291 media_request_object_put(&hdl->req_obj);
1295 * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1297 * @hdl: The control handler from the request.
1298 * @id: The ID of the control to find.
1300 * This function returns a pointer to the control if this control is
1301 * part of the request or NULL otherwise.
1304 v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1306 /* Helpers for ioctl_ops */
1309 * v4l2_queryctrl - Helper function to implement
1310 * :ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1312 * @hdl: pointer to &struct v4l2_ctrl_handler
1313 * @qc: pointer to &struct v4l2_queryctrl
1315 * If hdl == NULL then they will all return -EINVAL.
1317 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1320 * v4l2_query_ext_ctrl - Helper function to implement
1321 * :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1323 * @hdl: pointer to &struct v4l2_ctrl_handler
1324 * @qc: pointer to &struct v4l2_query_ext_ctrl
1326 * If hdl == NULL then they will all return -EINVAL.
1328 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1329 struct v4l2_query_ext_ctrl *qc);
1332 * v4l2_querymenu - Helper function to implement
1333 * :ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1335 * @hdl: pointer to &struct v4l2_ctrl_handler
1336 * @qm: pointer to &struct v4l2_querymenu
1338 * If hdl == NULL then they will all return -EINVAL.
1340 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1343 * v4l2_g_ctrl - Helper function to implement
1344 * :ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1346 * @hdl: pointer to &struct v4l2_ctrl_handler
1347 * @ctrl: pointer to &struct v4l2_control
1349 * If hdl == NULL then they will all return -EINVAL.
1351 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1354 * v4l2_s_ctrl - Helper function to implement
1355 * :ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1357 * @fh: pointer to &struct v4l2_fh
1358 * @hdl: pointer to &struct v4l2_ctrl_handler
1360 * @ctrl: pointer to &struct v4l2_control
1362 * If hdl == NULL then they will all return -EINVAL.
1364 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1365 struct v4l2_control *ctrl);
1368 * v4l2_g_ext_ctrls - Helper function to implement
1369 * :ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1371 * @hdl: pointer to &struct v4l2_ctrl_handler
1372 * @vdev: pointer to &struct video_device
1373 * @mdev: pointer to &struct media_device
1374 * @c: pointer to &struct v4l2_ext_controls
1376 * If hdl == NULL then they will all return -EINVAL.
1378 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1379 struct media_device *mdev, struct v4l2_ext_controls *c);
1382 * v4l2_try_ext_ctrls - Helper function to implement
1383 * :ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1385 * @hdl: pointer to &struct v4l2_ctrl_handler
1386 * @vdev: pointer to &struct video_device
1387 * @mdev: pointer to &struct media_device
1388 * @c: pointer to &struct v4l2_ext_controls
1390 * If hdl == NULL then they will all return -EINVAL.
1392 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1393 struct video_device *vdev,
1394 struct media_device *mdev,
1395 struct v4l2_ext_controls *c);
1398 * v4l2_s_ext_ctrls - Helper function to implement
1399 * :ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1401 * @fh: pointer to &struct v4l2_fh
1402 * @hdl: pointer to &struct v4l2_ctrl_handler
1403 * @vdev: pointer to &struct video_device
1404 * @mdev: pointer to &struct media_device
1405 * @c: pointer to &struct v4l2_ext_controls
1407 * If hdl == NULL then they will all return -EINVAL.
1409 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1410 struct video_device *vdev,
1411 struct media_device *mdev,
1412 struct v4l2_ext_controls *c);
1415 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1416 * as a &struct v4l2_subdev_core_ops subscribe_event function
1417 * that just subscribes control events.
1419 * @sd: pointer to &struct v4l2_subdev
1420 * @fh: pointer to &struct v4l2_fh
1421 * @sub: pointer to &struct v4l2_event_subscription
1423 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1424 struct v4l2_event_subscription *sub);
1427 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1430 * @sd: pointer to &struct v4l2_subdev
1432 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1435 * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1438 * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1439 * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1440 * @p: pointer to &struct v4l2_fwnode_device_properties
1442 * This function registers controls associated to device properties, using the
1443 * property values contained in @p parameter, if the property has been set to
1446 * Currently the following v4l2 controls are parsed and registered:
1447 * - V4L2_CID_CAMERA_ORIENTATION
1448 * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1450 * Controls already registered by the caller with the @hdl control handler are
1451 * not overwritten. Callers should register the controls they want to handle
1452 * themselves before calling this function.
1454 * Return: 0 on success, a negative error code on failure.
1456 int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1457 const struct v4l2_ctrl_ops *ctrl_ops,
1458 const struct v4l2_fwnode_device_properties *p);