1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 *  V4L2 controls support header.
   4 *
   5 *  Copyright (C) 2010  Hans Verkuil <hverkuil@xs4all.nl>
   6 */
   7
   8#ifndef _V4L2_CTRLS_H
   9#define _V4L2_CTRLS_H
  10
  11#include <linux/list.h>
  12#include <linux/mutex.h>
  13#include <linux/videodev2.h>
  14#include <media/media-request.h>
  15
  16/* forward references */
  17struct file;
  18struct poll_table_struct;
  19struct v4l2_ctrl;
  20struct v4l2_ctrl_handler;
  21struct v4l2_ctrl_helper;
  22struct v4l2_fh;
  23struct v4l2_fwnode_device_properties;
  24struct v4l2_subdev;
  25struct v4l2_subscribed_event;
  26struct video_device;
  27
  28/**
  29 * union v4l2_ctrl_ptr - A pointer to a control value.
  30 * @p_s32:			Pointer to a 32-bit signed value.
  31 * @p_s64:			Pointer to a 64-bit signed value.
  32 * @p_u8:			Pointer to a 8-bit unsigned value.
  33 * @p_u16:			Pointer to a 16-bit unsigned value.
  34 * @p_u32:			Pointer to a 32-bit unsigned value.
  35 * @p_char:			Pointer to a string.
  36 * @p_mpeg2_sequence:		Pointer to a MPEG2 sequence structure.
  37 * @p_mpeg2_picture:		Pointer to a MPEG2 picture structure.
  38 * @p_mpeg2_quantisation:	Pointer to a MPEG2 quantisation data structure.
  39 * @p_fwht_params:		Pointer to a FWHT stateless parameters structure.
  40 * @p_h264_sps:			Pointer to a struct v4l2_ctrl_h264_sps.
  41 * @p_h264_pps:			Pointer to a struct v4l2_ctrl_h264_pps.
  42 * @p_h264_scaling_matrix:	Pointer to a struct v4l2_ctrl_h264_scaling_matrix.
  43 * @p_h264_slice_params:	Pointer to a struct v4l2_ctrl_h264_slice_params.
  44 * @p_h264_decode_params:	Pointer to a struct v4l2_ctrl_h264_decode_params.
  45 * @p_h264_pred_weights:	Pointer to a struct v4l2_ctrl_h264_pred_weights.
  46 * @p_vp8_frame:		Pointer to a VP8 frame params structure.
  47 * @p_vp9_compressed_hdr_probs:	Pointer to a VP9 frame compressed header probs structure.
  48 * @p_vp9_frame:		Pointer to a VP9 frame params structure.
  49 * @p_hevc_sps:			Pointer to an HEVC sequence parameter set structure.
  50 * @p_hevc_pps:			Pointer to an HEVC picture parameter set structure.
  51 * @p_hevc_slice_params:	Pointer to an HEVC slice parameters structure.
  52 * @p_hdr10_cll:		Pointer to an HDR10 Content Light Level structure.
  53 * @p_hdr10_mastering:		Pointer to an HDR10 Mastering Display structure.
  54 * @p_area:			Pointer to an area.
  55 * @p_av1_sequence:		Pointer to an AV1 sequence structure.
  56 * @p_av1_tile_group_entry:	Pointer to an AV1 tile group entry structure.
  57 * @p_av1_frame:		Pointer to an AV1 frame structure.
  58 * @p_av1_film_grain:		Pointer to an AV1 film grain structure.
  59 * @p:				Pointer to a compound value.
  60 * @p_const:			Pointer to a constant compound value.
  61 */
  62union v4l2_ctrl_ptr {
  63	s32 *p_s32;
  64	s64 *p_s64;
  65	u8 *p_u8;
  66	u16 *p_u16;
  67	u32 *p_u32;
  68	char *p_char;
  69	struct v4l2_ctrl_mpeg2_sequence *p_mpeg2_sequence;
  70	struct v4l2_ctrl_mpeg2_picture *p_mpeg2_picture;
  71	struct v4l2_ctrl_mpeg2_quantisation *p_mpeg2_quantisation;
  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 *p_vp8_frame;
  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_ctrl_vp9_compressed_hdr *p_vp9_compressed_hdr_probs;
  84	struct v4l2_ctrl_vp9_frame *p_vp9_frame;
  85	struct v4l2_ctrl_hdr10_cll_info *p_hdr10_cll;
  86	struct v4l2_ctrl_hdr10_mastering_display *p_hdr10_mastering;
  87	struct v4l2_area *p_area;
  88	struct v4l2_ctrl_av1_sequence *p_av1_sequence;
  89	struct v4l2_ctrl_av1_tile_group_entry *p_av1_tile_group_entry;
  90	struct v4l2_ctrl_av1_frame *p_av1_frame;
  91	struct v4l2_ctrl_av1_film_grain *p_av1_film_grain;
  92	void *p;
  93	const void *p_const;
  94};
  95
  96/**
  97 * v4l2_ctrl_ptr_create() - Helper function to return a v4l2_ctrl_ptr from a
  98 * void pointer
  99 * @ptr:	The void pointer
 100 */
 101static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_create(void *ptr)
 102{
 103	union v4l2_ctrl_ptr p = { .p = ptr };
 104
 105	return p;
 106}
 107
 108/**
 109 * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
 110 *
 111 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
 112 *		for volatile (and usually read-only) controls such as a control
 113 *		that returns the current signal strength which changes
 114 *		continuously.
 115 *		If not set, then the currently cached value will be returned.
 116 * @try_ctrl:	Test whether the control's value is valid. Only relevant when
 117 *		the usual min/max/step checks are not sufficient.
 118 * @s_ctrl:	Actually set the new control value. s_ctrl is compulsory. The
 119 *		ctrl->handler->lock is held when these ops are called, so no
 120 *		one else can access controls owned by that handler.
 121 */
 122struct v4l2_ctrl_ops {
 123	int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
 124	int (*try_ctrl)(struct v4l2_ctrl *ctrl);
 125	int (*s_ctrl)(struct v4l2_ctrl *ctrl);
 126};
 127
 128/**
 129 * struct v4l2_ctrl_type_ops - The control type operations that the driver
 130 *			       has to provide.
 131 *
 132 * @equal: return true if all ctrl->elems array elements are equal.
 133 * @init: initialize the value for array elements from from_idx to ctrl->elems.
 134 * @log: log the value.
 135 * @validate: validate the value for ctrl->new_elems array elements.
 136 *	Return 0 on success and a negative value otherwise.
 137 */
 138struct v4l2_ctrl_type_ops {
 139	bool (*equal)(const struct v4l2_ctrl *ctrl,
 140		      union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
 141	void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx,
 142		     union v4l2_ctrl_ptr ptr);
 143	void (*log)(const struct v4l2_ctrl *ctrl);
 144	int (*validate)(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
 145};
 146
 147/**
 148 * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
 149 *	that should be called when a control value has changed.
 150 *
 151 * @ctrl: pointer to struct &v4l2_ctrl
 152 * @priv: control private data
 153 *
 154 * This typedef definition is used as an argument to v4l2_ctrl_notify()
 155 * and as an argument at struct &v4l2_ctrl_handler.
 156 */
 157typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
 158
 159/**
 160 * struct v4l2_ctrl - The control structure.
 161 *
 162 * @node:	The list node.
 163 * @ev_subs:	The list of control event subscriptions.
 164 * @handler:	The handler that owns the control.
 165 * @cluster:	Point to start of cluster array.
 166 * @ncontrols:	Number of controls in cluster array.
 167 * @done:	Internal flag: set for each processed control.
 168 * @is_new:	Set when the user specified a new value for this control. It
 169 *		is also set when called from v4l2_ctrl_handler_setup(). Drivers
 170 *		should never set this flag.
 171 * @has_changed: Set when the current value differs from the new value. Drivers
 172 *		should never use this flag.
 173 * @is_private: If set, then this control is private to its handler and it
 174 *		will not be added to any other handlers. Drivers can set
 175 *		this flag.
 176 * @is_auto:   If set, then this control selects whether the other cluster
 177 *		members are in 'automatic' mode or 'manual' mode. This is
 178 *		used for autogain/gain type clusters. Drivers should never
 179 *		set this flag directly.
 180 * @is_int:    If set, then this control has a simple integer value (i.e. it
 181 *		uses ctrl->val).
 182 * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
 183 * @is_ptr:	If set, then this control is an array and/or has type >=
 184 *		%V4L2_CTRL_COMPOUND_TYPES
 185 *		and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
 186 *		v4l2_ext_control uses field p to point to the data.
 187 * @is_array: If set, then this control contains an N-dimensional array.
 188 * @is_dyn_array: If set, then this control contains a dynamically sized 1-dimensional array.
 189 *		If this is set, then @is_array is also set.
 190 * @has_volatiles: If set, then one or more members of the cluster are volatile.
 191 *		Drivers should never touch this flag.
 192 * @call_notify: If set, then call the handler's notify function whenever the
 193 *		control's value changes.
 194 * @manual_mode_value: If the is_auto flag is set, then this is the value
 195 *		of the auto control that determines if that control is in
 196 *		manual mode. So if the value of the auto control equals this
 197 *		value, then the whole cluster is in manual mode. Drivers should
 198 *		never set this flag directly.
 199 * @ops:	The control ops.
 200 * @type_ops:	The control type ops.
 201 * @id:	The control ID.
 202 * @name:	The control name.
 203 * @type:	The control type.
 204 * @minimum:	The control's minimum value.
 205 * @maximum:	The control's maximum value.
 206 * @default_value: The control's default value.
 207 * @step:	The control's step value for non-menu controls.
 208 * @elems:	The number of elements in the N-dimensional array.
 209 * @elem_size:	The size in bytes of the control.
 210 * @new_elems:	The number of elements in p_new. This is the same as @elems,
 211 *		except for dynamic arrays. In that case it is in the range of
 212 *		1 to @p_array_alloc_elems.
 213 * @dims:	The size of each dimension.
 214 * @nr_of_dims:The number of dimensions in @dims.
 215 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
 216 *		easy to skip menu items that are not valid. If bit X is set,
 217 *		then menu item X is skipped. Of course, this only works for
 218 *		menus with <= 32 menu items. There are no menus that come
 219 *		close to that number, so this is OK. Should we ever need more,
 220 *		then this will have to be extended to a u64 or a bit array.
 221 * @qmenu:	A const char * array for all menu items. Array entries that are
 222 *		empty strings ("") correspond to non-existing menu items (this
 223 *		is in addition to the menu_skip_mask above). The last entry
 224 *		must be NULL.
 225 *		Used only if the @type is %V4L2_CTRL_TYPE_MENU.
 226 * @qmenu_int:	A 64-bit integer array for with integer menu items.
 227 *		The size of array must be equal to the menu size, e. g.:
 228 *		:math:`ceil(\frac{maximum - minimum}{step}) + 1`.
 229 *		Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
 230 * @flags:	The control's flags.
 231 * @priv:	The control's private pointer. For use by the driver. It is
 232 *		untouched by the control framework. Note that this pointer is
 233 *		not freed when the control is deleted. Should this be needed
 234 *		then a new internal bitfield can be added to tell the framework
 235 *		to free this pointer.
 236 * @p_array:	Pointer to the allocated array. Only valid if @is_array is true.
 237 * @p_array_alloc_elems: The number of elements in the allocated
 238 *		array for both the cur and new values. So @p_array is actually
 239 *		sized for 2 * @p_array_alloc_elems * @elem_size. Only valid if
 240 *		@is_array is true.
 241 * @cur:	Structure to store the current value.
 242 * @cur.val:	The control's current value, if the @type is represented via
 243 *		a u32 integer (see &enum v4l2_ctrl_type).
 244 * @val:	The control's new s32 value.
 245 * @p_def:	The control's default value represented via a union which
 246 *		provides a standard way of accessing control types
 247 *		through a pointer (for compound controls only).
 248 * @p_cur:	The control's current value represented via a union which
 249 *		provides a standard way of accessing control types
 250 *		through a pointer.
 251 * @p_new:	The control's new value represented via a union which provides
 252 *		a standard way of accessing control types
 253 *		through a pointer.
 254 */
 255struct v4l2_ctrl {
 256	/* Administrative fields */
 257	struct list_head node;
 258	struct list_head ev_subs;
 259	struct v4l2_ctrl_handler *handler;
 260	struct v4l2_ctrl **cluster;
 261	unsigned int ncontrols;
 262
 263	unsigned int done:1;
 264
 265	unsigned int is_new:1;
 266	unsigned int has_changed:1;
 267	unsigned int is_private:1;
 268	unsigned int is_auto:1;
 269	unsigned int is_int:1;
 270	unsigned int is_string:1;
 271	unsigned int is_ptr:1;
 272	unsigned int is_array:1;
 273	unsigned int is_dyn_array:1;
 274	unsigned int has_volatiles:1;
 275	unsigned int call_notify:1;
 276	unsigned int manual_mode_value:8;
 277
 278	const struct v4l2_ctrl_ops *ops;
 279	const struct v4l2_ctrl_type_ops *type_ops;
 280	u32 id;
 281	const char *name;
 282	enum v4l2_ctrl_type type;
 283	s64 minimum, maximum, default_value;
 284	u32 elems;
 285	u32 elem_size;
 286	u32 new_elems;
 287	u32 dims[V4L2_CTRL_MAX_DIMS];
 288	u32 nr_of_dims;
 289	union {
 290		u64 step;
 291		u64 menu_skip_mask;
 292	};
 293	union {
 294		const char * const *qmenu;
 295		const s64 *qmenu_int;
 296	};
 297	unsigned long flags;
 298	void *priv;
 299	void *p_array;
 300	u32 p_array_alloc_elems;
 301	s32 val;
 302	struct {
 303		s32 val;
 304	} cur;
 305
 306	union v4l2_ctrl_ptr p_def;
 307	union v4l2_ctrl_ptr p_new;
 308	union v4l2_ctrl_ptr p_cur;
 309};
 310
 311/**
 312 * struct v4l2_ctrl_ref - The control reference.
 313 *
 314 * @node:	List node for the sorted list.
 315 * @next:	Single-link list node for the hash.
 316 * @ctrl:	The actual control information.
 317 * @helper:	Pointer to helper struct. Used internally in
 318 *		``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
 319 * @from_other_dev: If true, then @ctrl was defined in another
 320 *		device than the &struct v4l2_ctrl_handler.
 321 * @req_done:	Internal flag: if the control handler containing this control
 322 *		reference is bound to a media request, then this is set when
 323 *		the control has been applied. This prevents applying controls
 324 *		from a cluster with multiple controls twice (when the first
 325 *		control of a cluster is applied, they all are).
 326 * @p_req_valid: If set, then p_req contains the control value for the request.
 327 * @p_req_array_enomem: If set, then p_req is invalid since allocating space for
 328 *		an array failed. Attempting to read this value shall
 329 *		result in ENOMEM. Only valid if ctrl->is_array is true.
 330 * @p_req_array_alloc_elems: The number of elements allocated for the
 331 *		array. Only valid if @p_req_valid and ctrl->is_array are
 332 *		true.
 333 * @p_req_elems: The number of elements in @p_req. This is the same as
 334 *		ctrl->elems, except for dynamic arrays. In that case it is in
 335 *		the range of 1 to @p_req_array_alloc_elems. Only valid if
 336 *		@p_req_valid is true.
 337 * @p_req:	If the control handler containing this control reference
 338 *		is bound to a media request, then this points to the
 339 *		value of the control that must be applied when the request
 340 *		is executed, or to the value of the control at the time
 341 *		that the request was completed. If @p_req_valid is false,
 342 *		then this control was never set for this request and the
 343 *		control will not be updated when this request is applied.
 344 *
 345 * Each control handler has a list of these refs. The list_head is used to
 346 * keep a sorted-by-control-ID list of all controls, while the next pointer
 347 * is used to link the control in the hash's bucket.
 348 */
 349struct v4l2_ctrl_ref {
 350	struct list_head node;
 351	struct v4l2_ctrl_ref *next;
 352	struct v4l2_ctrl *ctrl;
 353	struct v4l2_ctrl_helper *helper;
 354	bool from_other_dev;
 355	bool req_done;
 356	bool p_req_valid;
 357	bool p_req_array_enomem;
 358	u32 p_req_array_alloc_elems;
 359	u32 p_req_elems;
 360	union v4l2_ctrl_ptr p_req;
 361};
 362
 363/**
 364 * struct v4l2_ctrl_handler - The control handler keeps track of all the
 365 *	controls: both the controls owned by the handler and those inherited
 366 *	from other handlers.
 367 *
 368 * @_lock:	Default for "lock".
 369 * @lock:	Lock to control access to this handler and its controls.
 370 *		May be replaced by the user right after init.
 371 * @ctrls:	The list of controls owned by this handler.
 372 * @ctrl_refs:	The list of control references.
 373 * @cached:	The last found control reference. It is common that the same
 374 *		control is needed multiple times, so this is a simple
 375 *		optimization.
 376 * @buckets:	Buckets for the hashing. Allows for quick control lookup.
 377 * @notify:	A notify callback that is called whenever the control changes
 378 *		value.
 379 *		Note that the handler's lock is held when the notify function
 380 *		is called!
 381 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
 382 * @nr_of_buckets: Total number of buckets in the array.
 383 * @error:	The error code of the first failed control addition.
 384 * @request_is_queued: True if the request was queued.
 385 * @requests:	List to keep track of open control handler request objects.
 386 *		For the parent control handler (@req_obj.ops == NULL) this
 387 *		is the list header. When the parent control handler is
 388 *		removed, it has to unbind and put all these requests since
 389 *		they refer to the parent.
 390 * @requests_queued: List of the queued requests. This determines the order
 391 *		in which these controls are applied. Once the request is
 392 *		completed it is removed from this list.
 393 * @req_obj:	The &struct media_request_object, used to link into a
 394 *		&struct media_request. This request object has a refcount.
 395 */
 396struct v4l2_ctrl_handler {
 397	struct mutex _lock;
 398	struct mutex *lock;
 399	struct list_head ctrls;
 400	struct list_head ctrl_refs;
 401	struct v4l2_ctrl_ref *cached;
 402	struct v4l2_ctrl_ref **buckets;
 403	v4l2_ctrl_notify_fnc notify;
 404	void *notify_priv;
 405	u16 nr_of_buckets;
 406	int error;
 407	bool request_is_queued;
 408	struct list_head requests;
 409	struct list_head requests_queued;
 410	struct media_request_object req_obj;
 411};
 412
 413/**
 414 * struct v4l2_ctrl_config - Control configuration structure.
 415 *
 416 * @ops:	The control ops.
 417 * @type_ops:	The control type ops. Only needed for compound controls.
 418 * @id:	The control ID.
 419 * @name:	The control name.
 420 * @type:	The control type.
 421 * @min:	The control's minimum value.
 422 * @max:	The control's maximum value.
 423 * @step:	The control's step value for non-menu controls.
 424 * @def:	The control's default value.
 425 * @p_def:	The control's default value for compound controls.
 426 * @dims:	The size of each dimension.
 427 * @elem_size:	The size in bytes of the control.
 428 * @flags:	The control's flags.
 429 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
 430 *		easy to skip menu items that are not valid. If bit X is set,
 431 *		then menu item X is skipped. Of course, this only works for
 432 *		menus with <= 64 menu items. There are no menus that come
 433 *		close to that number, so this is OK. Should we ever need more,
 434 *		then this will have to be extended to a bit array.
 435 * @qmenu:	A const char * array for all menu items. Array entries that are
 436 *		empty strings ("") correspond to non-existing menu items (this
 437 *		is in addition to the menu_skip_mask above). The last entry
 438 *		must be NULL.
 439 * @qmenu_int:	A const s64 integer array for all menu items of the type
 440 *		V4L2_CTRL_TYPE_INTEGER_MENU.
 441 * @is_private: If set, then this control is private to its handler and it
 442 *		will not be added to any other handlers.
 443 */
 444struct v4l2_ctrl_config {
 445	const struct v4l2_ctrl_ops *ops;
 446	const struct v4l2_ctrl_type_ops *type_ops;
 447	u32 id;
 448	const char *name;
 449	enum v4l2_ctrl_type type;
 450	s64 min;
 451	s64 max;
 452	u64 step;
 453	s64 def;
 454	union v4l2_ctrl_ptr p_def;
 455	u32 dims[V4L2_CTRL_MAX_DIMS];
 456	u32 elem_size;
 457	u32 flags;
 458	u64 menu_skip_mask;
 459	const char * const *qmenu;
 460	const s64 *qmenu_int;
 461	unsigned int is_private:1;
 462};
 463
 464/**
 465 * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
 466 *
 467 * @id: ID of the control
 468 * @name: pointer to be filled with a string with the name of the control
 469 * @type: pointer for storing the type of the control
 470 * @min: pointer for storing the minimum value for the control
 471 * @max: pointer for storing the maximum value for the control
 472 * @step: pointer for storing the control step
 473 * @def: pointer for storing the default value for the control
 474 * @flags: pointer for storing the flags to be used on the control
 475 *
 476 * This works for all standard V4L2 controls.
 477 * For non-standard controls it will only fill in the given arguments
 478 * and @name content will be set to %NULL.
 479 *
 480 * This function will overwrite the contents of @name, @type and @flags.
 481 * The contents of @min, @max, @step and @def may be modified depending on
 482 * the type.
 483 *
 484 * .. note::
 485 *
 486 *    Do not use in drivers! It is used internally for backwards compatibility
 487 *    control handling only. Once all drivers are converted to use the new
 488 *    control framework this function will no longer be exported.
 489 */
 490void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 491		    s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
 492
 493
 494/**
 495 * v4l2_ctrl_handler_init_class() - Initialize the control handler.
 496 * @hdl:	The control handler.
 497 * @nr_of_controls_hint: A hint of how many controls this handler is
 498 *		expected to refer to. This is the total number, so including
 499 *		any inherited controls. It doesn't have to be precise, but if
 500 *		it is way off, then you either waste memory (too many buckets
 501 *		are allocated) or the control lookup becomes slower (not enough
 502 *		buckets are allocated, so there are more slow list lookups).
 503 *		It will always work, though.
 504 * @key:	Used by the lock validator if CONFIG_LOCKDEP is set.
 505 * @name:	Used by the lock validator if CONFIG_LOCKDEP is set.
 506 *
 507 * .. attention::
 508 *
 509 *    Never use this call directly, always use the v4l2_ctrl_handler_init()
 510 *    macro that hides the @key and @name arguments.
 511 *
 512 * Return: returns an error if the buckets could not be allocated. This
 513 * error will also be stored in @hdl->error.
 514 */
 515int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
 516				 unsigned int nr_of_controls_hint,
 517				 struct lock_class_key *key, const char *name);
 518
 519#ifdef CONFIG_LOCKDEP
 520
 521/**
 522 * v4l2_ctrl_handler_init - helper function to create a static struct
 523 *	 &lock_class_key and calls v4l2_ctrl_handler_init_class()
 524 *
 525 * @hdl:	The control handler.
 526 * @nr_of_controls_hint: A hint of how many controls this handler is
 527 *		expected to refer to. This is the total number, so including
 528 *		any inherited controls. It doesn't have to be precise, but if
 529 *		it is way off, then you either waste memory (too many buckets
 530 *		are allocated) or the control lookup becomes slower (not enough
 531 *		buckets are allocated, so there are more slow list lookups).
 532 *		It will always work, though.
 533 *
 534 * This helper function creates a static struct &lock_class_key and
 535 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
 536 * validador.
 537 *
 538 * Use this helper function to initialize a control handler.
 539 */
 540#define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
 541(									\
 542	({								\
 543		static struct lock_class_key _key;			\
 544		v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint,	\
 545					&_key,				\
 546					KBUILD_BASENAME ":"		\
 547					__stringify(__LINE__) ":"	\
 548					"(" #hdl ")->_lock");		\
 549	})								\
 550)
 551#else
 552#define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
 553	v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
 554#endif
 555
 556/**
 557 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
 558 * the control list.
 559 * @hdl:	The control handler.
 560 *
 561 * Does nothing if @hdl == NULL.
 562 */
 563void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
 564
 565/**
 566 * v4l2_ctrl_lock() - Helper function to lock the handler
 567 * associated with the control.
 568 * @ctrl:	The control to lock.
 569 */
 570static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
 571{
 572	mutex_lock(ctrl->handler->lock);
 573}
 574
 575/**
 576 * v4l2_ctrl_unlock() - Helper function to unlock the handler
 577 * associated with the control.
 578 * @ctrl:	The control to unlock.
 579 */
 580static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
 581{
 582	mutex_unlock(ctrl->handler->lock);
 583}
 584
 585/**
 586 * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
 587 * to the handler to initialize the hardware to the current control values. The
 588 * caller is responsible for acquiring the control handler mutex on behalf of
 589 * __v4l2_ctrl_handler_setup().
 590 * @hdl:	The control handler.
 591 *
 592 * Button controls will be skipped, as are read-only controls.
 593 *
 594 * If @hdl == NULL, then this just returns 0.
 595 */
 596int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
 597
 598/**
 599 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
 600 * to the handler to initialize the hardware to the current control values.
 601 * @hdl:	The control handler.
 602 *
 603 * Button controls will be skipped, as are read-only controls.
 604 *
 605 * If @hdl == NULL, then this just returns 0.
 606 */
 607int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
 608
 609/**
 610 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
 611 * @hdl:	The control handler.
 612 * @prefix:	The prefix to use when logging the control values. If the
 613 *		prefix does not end with a space, then ": " will be added
 614 *		after the prefix. If @prefix == NULL, then no prefix will be
 615 *		used.
 616 *
 617 * For use with VIDIOC_LOG_STATUS.
 618 *
 619 * Does nothing if @hdl == NULL.
 620 */
 621void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
 622				  const char *prefix);
 623
 624/**
 625 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
 626 *	control.
 627 *
 628 * @hdl:	The control handler.
 629 * @cfg:	The control's configuration data.
 630 * @priv:	The control's driver-specific private data.
 631 *
 632 * If the &v4l2_ctrl struct could not be allocated then NULL is returned
 633 * and @hdl->error is set to the error code (if it wasn't set already).
 634 */
 635struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
 636				       const struct v4l2_ctrl_config *cfg,
 637				       void *priv);
 638
 639/**
 640 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
 641 *	control.
 642 *
 643 * @hdl:	The control handler.
 644 * @ops:	The control ops.
 645 * @id:		The control ID.
 646 * @min:	The control's minimum value.
 647 * @max:	The control's maximum value.
 648 * @step:	The control's step value
 649 * @def:	The control's default value.
 650 *
 651 * If the &v4l2_ctrl struct could not be allocated, or the control
 652 * ID is not known, then NULL is returned and @hdl->error is set to the
 653 * appropriate error code (if it wasn't set already).
 654 *
 655 * If @id refers to a menu control, then this function will return NULL.
 656 *
 657 * Use v4l2_ctrl_new_std_menu() when adding menu controls.
 658 */
 659struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
 660				    const struct v4l2_ctrl_ops *ops,
 661				    u32 id, s64 min, s64 max, u64 step,
 662				    s64 def);
 663
 664/**
 665 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
 666 *	menu control.
 667 *
 668 * @hdl:	The control handler.
 669 * @ops:	The control ops.
 670 * @id:		The control ID.
 671 * @max:	The control's maximum value.
 672 * @mask:	The control's skip mask for menu controls. This makes it
 673 *		easy to skip menu items that are not valid. If bit X is set,
 674 *		then menu item X is skipped. Of course, this only works for
 675 *		menus with <= 64 menu items. There are no menus that come
 676 *		close to that number, so this is OK. Should we ever need more,
 677 *		then this will have to be extended to a bit array.
 678 * @def:	The control's default value.
 679 *
 680 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
 681 * determines which menu items are to be skipped.
 682 *
 683 * If @id refers to a non-menu control, then this function will return NULL.
 684 */
 685struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
 686					 const struct v4l2_ctrl_ops *ops,
 687					 u32 id, u8 max, u64 mask, u8 def);
 688
 689/**
 690 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
 691 *	with driver specific menu.
 692 *
 693 * @hdl:	The control handler.
 694 * @ops:	The control ops.
 695 * @id:	The control ID.
 696 * @max:	The control's maximum value.
 697 * @mask:	The control's skip mask for menu controls. This makes it
 698 *		easy to skip menu items that are not valid. If bit X is set,
 699 *		then menu item X is skipped. Of course, this only works for
 700 *		menus with <= 64 menu items. There are no menus that come
 701 *		close to that number, so this is OK. Should we ever need more,
 702 *		then this will have to be extended to a bit array.
 703 * @def:	The control's default value.
 704 * @qmenu:	The new menu.
 705 *
 706 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
 707 * menu of this control.
 708 *
 709 */
 710struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
 711					       const struct v4l2_ctrl_ops *ops,
 712					       u32 id, u8 max,
 713					       u64 mask, u8 def,
 714					       const char * const *qmenu);
 715
 716/**
 717 * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
 718 *      compound control.
 719 *
 720 * @hdl:       The control handler.
 721 * @ops:       The control ops.
 722 * @id:        The control ID.
 723 * @p_def:     The control's default value.
 724 *
 725 * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
 726 * to the @p_def field. Use v4l2_ctrl_ptr_create() to create @p_def from a
 727 * pointer. Use v4l2_ctrl_ptr_create(NULL) if the default value of the
 728 * compound control should be all zeroes.
 729 *
 730 */
 731struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
 732					     const struct v4l2_ctrl_ops *ops,
 733					     u32 id,
 734					     const union v4l2_ctrl_ptr p_def);
 735
 736/**
 737 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
 738 *
 739 * @hdl:	The control handler.
 740 * @ops:	The control ops.
 741 * @id:	The control ID.
 742 * @max:	The control's maximum value.
 743 * @def:	The control's default value.
 744 * @qmenu_int:	The control's menu entries.
 745 *
 746 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
 747 * takes as an argument an array of integers determining the menu items.
 748 *
 749 * If @id refers to a non-integer-menu control, then this function will
 750 * return %NULL.
 751 */
 752struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 753					 const struct v4l2_ctrl_ops *ops,
 754					 u32 id, u8 max, u8 def,
 755					 const s64 *qmenu_int);
 756
 757/**
 758 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
 759 *	used when adding a control handler.
 760 *
 761 * @ctrl: pointer to struct &v4l2_ctrl.
 762 */
 763
 764typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
 765
 766/**
 767 * v4l2_ctrl_add_handler() - Add all controls from handler @add to
 768 *	handler @hdl.
 769 *
 770 * @hdl:	The control handler.
 771 * @add:	The control handler whose controls you want to add to
 772 *		the @hdl control handler.
 773 * @filter:	This function will filter which controls should be added.
 774 * @from_other_dev: If true, then the controls in @add were defined in another
 775 *		device than @hdl.
 776 *
 777 * Does nothing if either of the two handlers is a NULL pointer.
 778 * If @filter is NULL, then all controls are added. Otherwise only those
 779 * controls for which @filter returns true will be added.
 780 * In case of an error @hdl->error will be set to the error code (if it
 781 * wasn't set already).
 782 */
 783int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
 784			  struct v4l2_ctrl_handler *add,
 785			  v4l2_ctrl_filter filter,
 786			  bool from_other_dev);
 787
 788/**
 789 * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
 790 *
 791 * @ctrl:	The control that is filtered.
 792 *
 793 * This will return true for any controls that are valid for radio device
 794 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
 795 * transmitter class controls.
 796 *
 797 * This function is to be used with v4l2_ctrl_add_handler().
 798 */
 799bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
 800
 801/**
 802 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
 803 *	to that cluster.
 804 *
 805 * @ncontrols:	The number of controls in this cluster.
 806 * @controls:	The cluster control array of size @ncontrols.
 807 */
 808void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
 809
 810
 811/**
 812 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
 813 *	to that cluster and set it up for autofoo/foo-type handling.
 814 *
 815 * @ncontrols:	The number of controls in this cluster.
 816 * @controls:	The cluster control array of size @ncontrols. The first control
 817 *		must be the 'auto' control (e.g. autogain, autoexposure, etc.)
 818 * @manual_val: The value for the first control in the cluster that equals the
 819 *		manual setting.
 820 * @set_volatile: If true, then all controls except the first auto control will
 821 *		be volatile.
 822 *
 823 * Use for control groups where one control selects some automatic feature and
 824 * the other controls are only active whenever the automatic feature is turned
 825 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
 826 * red and blue balance, etc.
 827 *
 828 * The behavior of such controls is as follows:
 829 *
 830 * When the autofoo control is set to automatic, then any manual controls
 831 * are set to inactive and any reads will call g_volatile_ctrl (if the control
 832 * was marked volatile).
 833 *
 834 * When the autofoo control is set to manual, then any manual controls will
 835 * be marked active, and any reads will just return the current value without
 836 * going through g_volatile_ctrl.
 837 *
 838 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
 839 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
 840 * if autofoo is in auto mode.
 841 */
 842void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
 843			    struct v4l2_ctrl **controls,
 844			    u8 manual_val, bool set_volatile);
 845
 846
 847/**
 848 * v4l2_ctrl_find() - Find a control with the given ID.
 849 *
 850 * @hdl:	The control handler.
 851 * @id:	The control ID to find.
 852 *
 853 * If @hdl == NULL this will return NULL as well. Will lock the handler so
 854 * do not use from inside &v4l2_ctrl_ops.
 855 */
 856struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
 857
 858/**
 859 * v4l2_ctrl_activate() - Make the control active or inactive.
 860 * @ctrl:	The control to (de)activate.
 861 * @active:	True if the control should become active.
 862 *
 863 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
 864 * Does nothing if @ctrl == NULL.
 865 * This will usually be called from within the s_ctrl op.
 866 * The V4L2_EVENT_CTRL event will be generated afterwards.
 867 *
 868 * This function assumes that the control handler is locked.
 869 */
 870void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
 871
 872/**
 873 * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
 874 *
 875 * @ctrl:	The control to (de)activate.
 876 * @grabbed:	True if the control should become grabbed.
 877 *
 878 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
 879 * Does nothing if @ctrl == NULL.
 880 * The V4L2_EVENT_CTRL event will be generated afterwards.
 881 * This will usually be called when starting or stopping streaming in the
 882 * driver.
 883 *
 884 * This function assumes that the control handler is locked by the caller.
 885 */
 886void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
 887
 888/**
 889 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
 890 *
 891 * @ctrl:	The control to (de)activate.
 892 * @grabbed:	True if the control should become grabbed.
 893 *
 894 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
 895 * Does nothing if @ctrl == NULL.
 896 * The V4L2_EVENT_CTRL event will be generated afterwards.
 897 * This will usually be called when starting or stopping streaming in the
 898 * driver.
 899 *
 900 * This function assumes that the control handler is not locked and will
 901 * take the lock itself.
 902 */
 903static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
 904{
 905	if (!ctrl)
 906		return;
 907
 908	v4l2_ctrl_lock(ctrl);
 909	__v4l2_ctrl_grab(ctrl, grabbed);
 910	v4l2_ctrl_unlock(ctrl);
 911}
 912
 913/**
 914 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
 915 *
 916 * @ctrl:	The control to update.
 917 * @min:	The control's minimum value.
 918 * @max:	The control's maximum value.
 919 * @step:	The control's step value
 920 * @def:	The control's default value.
 921 *
 922 * Update the range of a control on the fly. This works for control types
 923 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
 924 * @step value is interpreted as a menu_skip_mask.
 925 *
 926 * An error is returned if one of the range arguments is invalid for this
 927 * control type.
 928 *
 929 * The caller is responsible for acquiring the control handler mutex on behalf
 930 * of __v4l2_ctrl_modify_range().
 931 */
 932int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
 933			     s64 min, s64 max, u64 step, s64 def);
 934
 935/**
 936 * v4l2_ctrl_modify_range() - Update the range of a control.
 937 *
 938 * @ctrl:	The control to update.
 939 * @min:	The control's minimum value.
 940 * @max:	The control's maximum value.
 941 * @step:	The control's step value
 942 * @def:	The control's default value.
 943 *
 944 * Update the range of a control on the fly. This works for control types
 945 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
 946 * @step value is interpreted as a menu_skip_mask.
 947 *
 948 * An error is returned if one of the range arguments is invalid for this
 949 * control type.
 950 *
 951 * This function assumes that the control handler is not locked and will
 952 * take the lock itself.
 953 */
 954static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
 955					 s64 min, s64 max, u64 step, s64 def)
 956{
 957	int rval;
 958
 959	v4l2_ctrl_lock(ctrl);
 960	rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
 961	v4l2_ctrl_unlock(ctrl);
 962
 963	return rval;
 964}
 965
 966/**
 967 *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
 968 *
 969 * @ctrl:	The control to update.
 970 * @dims:	The control's new dimensions.
 971 *
 972 * Update the dimensions of an array control on the fly. The elements of the
 973 * array are reset to their default value, even if the dimensions are
 974 * unchanged.
 975 *
 976 * An error is returned if @dims is invalid for this control.
 977 *
 978 * The caller is responsible for acquiring the control handler mutex on behalf
 979 * of __v4l2_ctrl_modify_dimensions().
 980 *
 981 * Note: calling this function when the same control is used in pending requests
 982 * is untested. It should work (a request with the wrong size of the control
 983 * will drop that control silently), but it will be very confusing.
 984 */
 985int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
 986				  u32 dims[V4L2_CTRL_MAX_DIMS]);
 987
 988/**
 989 * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
 990 *
 991 * @ctrl:	The control to update.
 992 * @dims:	The control's new dimensions.
 993 *
 994 * Update the dimensions of an array control on the fly. The elements of the
 995 * array are reset to their default value, even if the dimensions are
 996 * unchanged.
 997 *
 998 * An error is returned if @dims is invalid for this control type.
 999 *
1000 * This function assumes that the control handler is not locked and will
1001 * take the lock itself.
1002 *
1003 * Note: calling this function when the same control is used in pending requests
1004 * is untested. It should work (a request with the wrong size of the control
1005 * will drop that control silently), but it will be very confusing.
1006 */
1007static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1008					      u32 dims[V4L2_CTRL_MAX_DIMS])
1009{
1010	int rval;
1011
1012	v4l2_ctrl_lock(ctrl);
1013	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1014	v4l2_ctrl_unlock(ctrl);
1015
1016	return rval;
1017}
1018
1019/**
1020 * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1021 *
1022 * @ctrl:	The control.
1023 * @notify:	The callback function.
1024 * @priv:	The callback private handle, passed as argument to the callback.
1025 *
1026 * This function sets a callback function for the control. If @ctrl is NULL,
1027 * then it will do nothing. If @notify is NULL, then the notify callback will
1028 * be removed.
1029 *
1030 * There can be only one notify. If another already exists, then a WARN_ON
1031 * will be issued and the function will do nothing.
1032 */
1033void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1034		      void *priv);
1035
1036/**
1037 * v4l2_ctrl_get_name() - Get the name of the control
1038 *
1039 * @id:		The control ID.
1040 *
1041 * This function returns the name of the given control ID or NULL if it isn't
1042 * a known control.
1043 */
1044const char *v4l2_ctrl_get_name(u32 id);
1045
1046/**
1047 * v4l2_ctrl_get_menu() - Get the menu string array of the control
1048 *
1049 * @id:		The control ID.
1050 *
1051 * This function returns the NULL-terminated menu string array name of the
1052 * given control ID or NULL if it isn't a known menu control.
1053 */
1054const char * const *v4l2_ctrl_get_menu(u32 id);
1055
1056/**
1057 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1058 *
1059 * @id:		The control ID.
1060 * @len:	The size of the integer array.
1061 *
1062 * This function returns the integer array of the given control ID or NULL if it
1063 * if it isn't a known integer menu control.
1064 */
1065const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1066
1067/**
1068 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1069 *	within a driver.
1070 *
1071 * @ctrl:	The control.
1072 *
1073 * This returns the control's value safely by going through the control
1074 * framework. This function will lock the control's handler, so it cannot be
1075 * used from within the &v4l2_ctrl_ops functions.
1076 *
1077 * This function is for integer type controls only.
1078 */
1079s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1080
1081/**
1082 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1083 *
1084 * @ctrl:	The control.
1085 * @val:	The new value.
1086 *
1087 * This sets the control's new value safely by going through the control
1088 * framework. This function assumes the control's handler is already locked,
1089 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1090 *
1091 * This function is for integer type controls only.
1092 */
1093int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1094
1095/**
1096 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1097 *	within a driver.
1098 * @ctrl:	The control.
1099 * @val:	The new value.
1100 *
1101 * This sets the control's new value safely by going through the control
1102 * framework. This function will lock the control's handler, so it cannot be
1103 * used from within the &v4l2_ctrl_ops functions.
1104 *
1105 * This function is for integer type controls only.
1106 */
1107static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1108{
1109	int rval;
1110
1111	v4l2_ctrl_lock(ctrl);
1112	rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1113	v4l2_ctrl_unlock(ctrl);
1114
1115	return rval;
1116}
1117
1118/**
1119 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1120 *	from within a driver.
1121 *
1122 * @ctrl:	The control.
1123 *
1124 * This returns the control's value safely by going through the control
1125 * framework. This function will lock the control's handler, so it cannot be
1126 * used from within the &v4l2_ctrl_ops functions.
1127 *
1128 * This function is for 64-bit integer type controls only.
1129 */
1130s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1131
1132/**
1133 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1134 *
1135 * @ctrl:	The control.
1136 * @val:	The new value.
1137 *
1138 * This sets the control's new value safely by going through the control
1139 * framework. This function assumes the control's handler is already locked,
1140 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1141 *
1142 * This function is for 64-bit integer type controls only.
1143 */
1144int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1145
1146/**
1147 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1148 *	from within a driver.
1149 *
1150 * @ctrl:	The control.
1151 * @val:	The new value.
1152 *
1153 * This sets the control's new value safely by going through the control
1154 * framework. This function will lock the control's handler, so it cannot be
1155 * used from within the &v4l2_ctrl_ops functions.
1156 *
1157 * This function is for 64-bit integer type controls only.
1158 */
1159static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1160{
1161	int rval;
1162
1163	v4l2_ctrl_lock(ctrl);
1164	rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1165	v4l2_ctrl_unlock(ctrl);
1166
1167	return rval;
1168}
1169
1170/**
1171 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1172 *
1173 * @ctrl:	The control.
1174 * @s:		The new string.
1175 *
1176 * This sets the control's new string safely by going through the control
1177 * framework. This function assumes the control's handler is already locked,
1178 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1179 *
1180 * This function is for string type controls only.
1181 */
1182int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1183
1184/**
1185 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1186 *	 from within a driver.
1187 *
1188 * @ctrl:	The control.
1189 * @s:		The new string.
1190 *
1191 * This sets the control's new string safely by going through the control
1192 * framework. This function will lock the control's handler, so it cannot be
1193 * used from within the &v4l2_ctrl_ops functions.
1194 *
1195 * This function is for string type controls only.
1196 */
1197static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1198{
1199	int rval;
1200
1201	v4l2_ctrl_lock(ctrl);
1202	rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1203	v4l2_ctrl_unlock(ctrl);
1204
1205	return rval;
1206}
1207
1208/**
1209 * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1210 *
1211 * @ctrl: The control.
1212 * @type: The type of the data.
1213 * @p:    The new compound payload.
1214 *
1215 * This sets the control's new compound payload safely by going through the
1216 * control framework. This function assumes the control's handler is already
1217 * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1218 *
1219 * This function is for compound type controls only.
1220 */
1221int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1222				enum v4l2_ctrl_type type, const void *p);
1223
1224/**
1225 * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1226 *	from within a driver.
1227 *
1228 * @ctrl: The control.
1229 * @type: The type of the data.
1230 * @p:    The new compound payload.
1231 *
1232 * This sets the control's new compound payload safely by going through the
1233 * control framework. This function will lock the control's handler, so it
1234 * cannot be used from within the &v4l2_ctrl_ops functions.
1235 *
1236 * This function is for compound type controls only.
1237 */
1238static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1239					    enum v4l2_ctrl_type type,
1240					    const void *p)
1241{
1242	int rval;
1243
1244	v4l2_ctrl_lock(ctrl);
1245	rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1246	v4l2_ctrl_unlock(ctrl);
1247
1248	return rval;
1249}
1250
1251/* Helper defines for area type controls */
1252#define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1253	__v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1254#define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1255	v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1256
1257/* Internal helper functions that deal with control events. */
1258extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1259
1260/**
1261 * v4l2_ctrl_replace - Function to be used as a callback to
1262 *	&struct v4l2_subscribed_event_ops replace\(\)
1263 *
1264 * @old: pointer to struct &v4l2_event with the reported
1265 *	 event;
1266 * @new: pointer to struct &v4l2_event with the modified
1267 *	 event;
1268 */
1269void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1270
1271/**
1272 * v4l2_ctrl_merge - Function to be used as a callback to
1273 *	&struct v4l2_subscribed_event_ops merge(\)
1274 *
1275 * @old: pointer to struct &v4l2_event with the reported
1276 *	 event;
1277 * @new: pointer to struct &v4l2_event with the merged
1278 *	 event;
1279 */
1280void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1281
1282/**
1283 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1284 *
1285 * @file: pointer to struct file
1286 * @fh: unused. Kept just to be compatible to the arguments expected by
1287 *	&struct v4l2_ioctl_ops.vidioc_log_status.
1288 *
1289 * Can be used as a vidioc_log_status function that just dumps all controls
1290 * associated with the filehandle.
1291 */
1292int v4l2_ctrl_log_status(struct file *file, void *fh);
1293
1294/**
1295 * v4l2_ctrl_subscribe_event - Subscribes to an event
1296 *
1297 *
1298 * @fh: pointer to struct v4l2_fh
1299 * @sub: pointer to &struct v4l2_event_subscription
1300 *
1301 * Can be used as a vidioc_subscribe_event function that just subscribes
1302 * control events.
1303 */
1304int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1305				const struct v4l2_event_subscription *sub);
1306
1307/**
1308 * v4l2_ctrl_poll - function to be used as a callback to the poll()
1309 *	That just polls for control events.
1310 *
1311 * @file: pointer to struct file
1312 * @wait: pointer to struct poll_table_struct
1313 */
1314__poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1315
1316/**
1317 * v4l2_ctrl_request_setup - helper function to apply control values in a request
1318 *
1319 * @req: The request
1320 * @parent: The parent control handler ('priv' in media_request_object_find())
1321 *
1322 * This is a helper function to call the control handler's s_ctrl callback with
1323 * the control values contained in the request. Do note that this approach of
1324 * applying control values in a request is only applicable to memory-to-memory
1325 * devices.
1326 */
1327int v4l2_ctrl_request_setup(struct media_request *req,
1328			     struct v4l2_ctrl_handler *parent);
1329
1330/**
1331 * v4l2_ctrl_request_complete - Complete a control handler request object
1332 *
1333 * @req: The request
1334 * @parent: The parent control handler ('priv' in media_request_object_find())
1335 *
1336 * This function is to be called on each control handler that may have had a
1337 * request object associated with it, i.e. control handlers of a driver that
1338 * supports requests.
1339 *
1340 * The function first obtains the values of any volatile controls in the control
1341 * handler and attach them to the request. Then, the function completes the
1342 * request object.
1343 */
1344void v4l2_ctrl_request_complete(struct media_request *req,
1345				struct v4l2_ctrl_handler *parent);
1346
1347/**
1348 * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1349 *
1350 * @req: The request
1351 * @parent: The parent control handler ('priv' in media_request_object_find())
1352 *
1353 * This function finds the control handler in the request. It may return
1354 * NULL if not found. When done, you must call v4l2_ctrl_request_hdl_put()
1355 * with the returned handler pointer.
1356 *
1357 * If the request is not in state VALIDATING or QUEUED, then this function
1358 * will always return NULL.
1359 *
1360 * Note that in state VALIDATING the req_queue_mutex is held, so
1361 * no objects can be added or deleted from the request.
1362 *
1363 * In state QUEUED it is the driver that will have to ensure this.
1364 */
1365struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1366					struct v4l2_ctrl_handler *parent);
1367
1368/**
1369 * v4l2_ctrl_request_hdl_put - Put the control handler
1370 *
1371 * @hdl: Put this control handler
1372 *
1373 * This function released the control handler previously obtained from'
1374 * v4l2_ctrl_request_hdl_find().
1375 */
1376static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1377{
1378	if (hdl)
1379		media_request_object_put(&hdl->req_obj);
1380}
1381
1382/**
1383 * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1384 *
1385 * @hdl: The control handler from the request.
1386 * @id: The ID of the control to find.
1387 *
1388 * This function returns a pointer to the control if this control is
1389 * part of the request or NULL otherwise.
1390 */
1391struct v4l2_ctrl *
1392v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1393
1394/* Helpers for ioctl_ops */
1395
1396/**
1397 * v4l2_queryctrl - Helper function to implement
1398 *	:ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1399 *
1400 * @hdl: pointer to &struct v4l2_ctrl_handler
1401 * @qc: pointer to &struct v4l2_queryctrl
1402 *
1403 * If hdl == NULL then they will all return -EINVAL.
1404 */
1405int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1406
1407/**
1408 * v4l2_query_ext_ctrl - Helper function to implement
1409 *	 :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1410 *
1411 * @hdl: pointer to &struct v4l2_ctrl_handler
1412 * @qc: pointer to &struct v4l2_query_ext_ctrl
1413 *
1414 * If hdl == NULL then they will all return -EINVAL.
1415 */
1416int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1417			struct v4l2_query_ext_ctrl *qc);
1418
1419/**
1420 * v4l2_querymenu - Helper function to implement
1421 *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1422 *
1423 * @hdl: pointer to &struct v4l2_ctrl_handler
1424 * @qm: pointer to &struct v4l2_querymenu
1425 *
1426 * If hdl == NULL then they will all return -EINVAL.
1427 */
1428int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1429
1430/**
1431 * v4l2_g_ctrl - Helper function to implement
1432 *	:ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1433 *
1434 * @hdl: pointer to &struct v4l2_ctrl_handler
1435 * @ctrl: pointer to &struct v4l2_control
1436 *
1437 * If hdl == NULL then they will all return -EINVAL.
1438 */
1439int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1440
1441/**
1442 * v4l2_s_ctrl - Helper function to implement
1443 *	:ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1444 *
1445 * @fh: pointer to &struct v4l2_fh
1446 * @hdl: pointer to &struct v4l2_ctrl_handler
1447 *
1448 * @ctrl: pointer to &struct v4l2_control
1449 *
1450 * If hdl == NULL then they will all return -EINVAL.
1451 */
1452int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1453		struct v4l2_control *ctrl);
1454
1455/**
1456 * v4l2_g_ext_ctrls - Helper function to implement
1457 *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1458 *
1459 * @hdl: pointer to &struct v4l2_ctrl_handler
1460 * @vdev: pointer to &struct video_device
1461 * @mdev: pointer to &struct media_device
1462 * @c: pointer to &struct v4l2_ext_controls
1463 *
1464 * If hdl == NULL then they will all return -EINVAL.
1465 */
1466int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1467		     struct media_device *mdev, struct v4l2_ext_controls *c);
1468
1469/**
1470 * v4l2_try_ext_ctrls - Helper function to implement
1471 *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1472 *
1473 * @hdl: pointer to &struct v4l2_ctrl_handler
1474 * @vdev: pointer to &struct video_device
1475 * @mdev: pointer to &struct media_device
1476 * @c: pointer to &struct v4l2_ext_controls
1477 *
1478 * If hdl == NULL then they will all return -EINVAL.
1479 */
1480int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1481		       struct video_device *vdev,
1482		       struct media_device *mdev,
1483		       struct v4l2_ext_controls *c);
1484
1485/**
1486 * v4l2_s_ext_ctrls - Helper function to implement
1487 *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1488 *
1489 * @fh: pointer to &struct v4l2_fh
1490 * @hdl: pointer to &struct v4l2_ctrl_handler
1491 * @vdev: pointer to &struct video_device
1492 * @mdev: pointer to &struct media_device
1493 * @c: pointer to &struct v4l2_ext_controls
1494 *
1495 * If hdl == NULL then they will all return -EINVAL.
1496 */
1497int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1498		     struct video_device *vdev,
1499		     struct media_device *mdev,
1500		     struct v4l2_ext_controls *c);
1501
1502/**
1503 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1504 *	as a &struct v4l2_subdev_core_ops subscribe_event function
1505 *	that just subscribes control events.
1506 *
1507 * @sd: pointer to &struct v4l2_subdev
1508 * @fh: pointer to &struct v4l2_fh
1509 * @sub: pointer to &struct v4l2_event_subscription
1510 */
1511int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1512				     struct v4l2_event_subscription *sub);
1513
1514/**
1515 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1516 *	 handler.
1517 *
1518 * @sd: pointer to &struct v4l2_subdev
1519 */
1520int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1521
1522/**
1523 * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1524 *				       properties
1525 *
1526 * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1527 * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1528 * @p: pointer to &struct v4l2_fwnode_device_properties
1529 *
1530 * This function registers controls associated to device properties, using the
1531 * property values contained in @p parameter, if the property has been set to
1532 * a value.
1533 *
1534 * Currently the following v4l2 controls are parsed and registered:
1535 * - V4L2_CID_CAMERA_ORIENTATION
1536 * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1537 *
1538 * Controls already registered by the caller with the @hdl control handler are
1539 * not overwritten. Callers should register the controls they want to handle
1540 * themselves before calling this function.
1541 *
1542 * Return: 0 on success, a negative error code on failure.
1543 */
1544int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1545				    const struct v4l2_ctrl_ops *ctrl_ops,
1546				    const struct v4l2_fwnode_device_properties *p);
1547
1548/**
1549 * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1550 *
1551 * @ctrl: The v4l2_ctrl pointer.
1552 * @ptr1: A v4l2 control value.
1553 * @ptr2: A v4l2 control value.
1554 *
1555 * Return: true if values are equal, otherwise false.
1556 */
1557bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl,
1558			     union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1559
1560/**
1561 * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1562 *
1563 * @ctrl: The v4l2_ctrl pointer.
1564 * @from_idx: Starting element index.
1565 * @ptr: The v4l2 control value.
1566 *
1567 * Return: void
1568 */
1569void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1570			    union v4l2_ctrl_ptr ptr);
1571
1572/**
1573 * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1574 *
1575 * @ctrl: The v4l2_ctrl pointer.
1576 *
1577 * Return: void
1578 */
1579void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1580
1581/**
1582 * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1583 *
1584 * @ctrl: The v4l2_ctrl pointer.
1585 * @ptr: The v4l2 control value.
1586 *
1587 * Return: 0 on success, a negative error code on failure.
1588 */
1589int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1590
1591#endif