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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * V4L2 controls support header.
4 *
5 * Copyright (C) 2010 Hans Verkuil <[email protected]>
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_rect: Pointer to a rectangle.
60 * @p: Pointer to a compound value.
61 * @p_const: Pointer to a constant compound value.
62 */
63union v4l2_ctrl_ptr {
64 s32 *p_s32;
65 s64 *p_s64;
66 u8 *p_u8;
67 u16 *p_u16;
68 u32 *p_u32;
69 char *p_char;
70 struct v4l2_ctrl_mpeg2_sequence *p_mpeg2_sequence;
71 struct v4l2_ctrl_mpeg2_picture *p_mpeg2_picture;
72 struct v4l2_ctrl_mpeg2_quantisation *p_mpeg2_quantisation;
73 struct v4l2_ctrl_fwht_params *p_fwht_params;
74 struct v4l2_ctrl_h264_sps *p_h264_sps;
75 struct v4l2_ctrl_h264_pps *p_h264_pps;
76 struct v4l2_ctrl_h264_scaling_matrix *p_h264_scaling_matrix;
77 struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
78 struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
79 struct v4l2_ctrl_h264_pred_weights *p_h264_pred_weights;
80 struct v4l2_ctrl_vp8_frame *p_vp8_frame;
81 struct v4l2_ctrl_hevc_sps *p_hevc_sps;
82 struct v4l2_ctrl_hevc_pps *p_hevc_pps;
83 struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
84 struct v4l2_ctrl_vp9_compressed_hdr *p_vp9_compressed_hdr_probs;
85 struct v4l2_ctrl_vp9_frame *p_vp9_frame;
86 struct v4l2_ctrl_hdr10_cll_info *p_hdr10_cll;
87 struct v4l2_ctrl_hdr10_mastering_display *p_hdr10_mastering;
88 struct v4l2_area *p_area;
89 struct v4l2_ctrl_av1_sequence *p_av1_sequence;
90 struct v4l2_ctrl_av1_tile_group_entry *p_av1_tile_group_entry;
91 struct v4l2_ctrl_av1_frame *p_av1_frame;
92 struct v4l2_ctrl_av1_film_grain *p_av1_film_grain;
93 struct v4l2_rect *p_rect;
94 void *p;
95 const void *p_const;
96};
97
98/**
99 * v4l2_ctrl_ptr_create() - Helper function to return a v4l2_ctrl_ptr from a
100 * void pointer
101 * @ptr: The void pointer
102 */
103static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_create(void *ptr)
104{
105 union v4l2_ctrl_ptr p = { .p = ptr };
106
107 return p;
108}
109
110/**
111 * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
112 *
113 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
114 * for volatile (and usually read-only) controls such as a control
115 * that returns the current signal strength which changes
116 * continuously.
117 * If not set, then the currently cached value will be returned.
118 * @try_ctrl: Test whether the control's value is valid. Only relevant when
119 * the usual min/max/step checks are not sufficient.
120 * @s_ctrl: Actually set the new control value. s_ctrl is compulsory. The
121 * ctrl->handler->lock is held when these ops are called, so no
122 * one else can access controls owned by that handler.
123 */
124struct v4l2_ctrl_ops {
125 int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
126 int (*try_ctrl)(struct v4l2_ctrl *ctrl);
127 int (*s_ctrl)(struct v4l2_ctrl *ctrl);
128};
129
130/**
131 * struct v4l2_ctrl_type_ops - The control type operations that the driver
132 * has to provide.
133 *
134 * @equal: return true if all ctrl->elems array elements are equal.
135 * @init: initialize the value for array elements from from_idx to ctrl->elems.
136 * @minimum: set the value to the minimum value of the control.
137 * @maximum: set the value to the maximum value of the control.
138 * @log: log the value.
139 * @validate: validate the value for ctrl->new_elems array elements.
140 * Return 0 on success and a negative value otherwise.
141 */
142struct v4l2_ctrl_type_ops {
143 bool (*equal)(const struct v4l2_ctrl *ctrl,
144 union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
145 void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx,
146 union v4l2_ctrl_ptr ptr);
147 void (*minimum)(const struct v4l2_ctrl *ctrl, u32 idx,
148 union v4l2_ctrl_ptr ptr);
149 void (*maximum)(const struct v4l2_ctrl *ctrl, u32 idx,
150 union v4l2_ctrl_ptr ptr);
151 void (*log)(const struct v4l2_ctrl *ctrl);
152 int (*validate)(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
153};
154
155/**
156 * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
157 * that should be called when a control value has changed.
158 *
159 * @ctrl: pointer to struct &v4l2_ctrl
160 * @priv: control private data
161 *
162 * This typedef definition is used as an argument to v4l2_ctrl_notify()
163 * and as an argument at struct &v4l2_ctrl_handler.
164 */
165typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
166
167/**
168 * struct v4l2_ctrl - The control structure.
169 *
170 * @node: The list node.
171 * @ev_subs: The list of control event subscriptions.
172 * @handler: The handler that owns the control.
173 * @cluster: Point to start of cluster array.
174 * @ncontrols: Number of controls in cluster array.
175 * @done: Internal flag: set for each processed control.
176 * @is_new: Set when the user specified a new value for this control. It
177 * is also set when called from v4l2_ctrl_handler_setup(). Drivers
178 * should never set this flag.
179 * @has_changed: Set when the current value differs from the new value. Drivers
180 * should never use this flag.
181 * @is_private: If set, then this control is private to its handler and it
182 * will not be added to any other handlers. Drivers can set
183 * this flag.
184 * @is_auto: If set, then this control selects whether the other cluster
185 * members are in 'automatic' mode or 'manual' mode. This is
186 * used for autogain/gain type clusters. Drivers should never
187 * set this flag directly.
188 * @is_int: If set, then this control has a simple integer value (i.e. it
189 * uses ctrl->val).
190 * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
191 * @is_ptr: If set, then this control is an array and/or has type >=
192 * %V4L2_CTRL_COMPOUND_TYPES
193 * and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
194 * v4l2_ext_control uses field p to point to the data.
195 * @is_array: If set, then this control contains an N-dimensional array.
196 * @is_dyn_array: If set, then this control contains a dynamically sized 1-dimensional array.
197 * If this is set, then @is_array is also set.
198 * @has_volatiles: If set, then one or more members of the cluster are volatile.
199 * Drivers should never touch this flag.
200 * @call_notify: If set, then call the handler's notify function whenever the
201 * control's value changes.
202 * @manual_mode_value: If the is_auto flag is set, then this is the value
203 * of the auto control that determines if that control is in
204 * manual mode. So if the value of the auto control equals this
205 * value, then the whole cluster is in manual mode. Drivers should
206 * never set this flag directly.
207 * @ops: The control ops.
208 * @type_ops: The control type ops.
209 * @id: The control ID.
210 * @name: The control name.
211 * @type: The control type.
212 * @minimum: The control's minimum value.
213 * @maximum: The control's maximum value.
214 * @default_value: The control's default value.
215 * @step: The control's step value for non-menu controls.
216 * @elems: The number of elements in the N-dimensional array.
217 * @elem_size: The size in bytes of the control.
218 * @new_elems: The number of elements in p_new. This is the same as @elems,
219 * except for dynamic arrays. In that case it is in the range of
220 * 1 to @p_array_alloc_elems.
221 * @dims: The size of each dimension.
222 * @nr_of_dims:The number of dimensions in @dims.
223 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
224 * easy to skip menu items that are not valid. If bit X is set,
225 * then menu item X is skipped. Of course, this only works for
226 * menus with <= 32 menu items. There are no menus that come
227 * close to that number, so this is OK. Should we ever need more,
228 * then this will have to be extended to a u64 or a bit array.
229 * @qmenu: A const char * array for all menu items. Array entries that are
230 * empty strings ("") correspond to non-existing menu items (this
231 * is in addition to the menu_skip_mask above). The last entry
232 * must be NULL.
233 * Used only if the @type is %V4L2_CTRL_TYPE_MENU.
234 * @qmenu_int: A 64-bit integer array for with integer menu items.
235 * The size of array must be equal to the menu size, e. g.:
236 * :math:`ceil(\frac{maximum - minimum}{step}) + 1`.
237 * Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
238 * @flags: The control's flags.
239 * @priv: The control's private pointer. For use by the driver. It is
240 * untouched by the control framework. Note that this pointer is
241 * not freed when the control is deleted. Should this be needed
242 * then a new internal bitfield can be added to tell the framework
243 * to free this pointer.
244 * @p_array: Pointer to the allocated array. Only valid if @is_array is true.
245 * @p_array_alloc_elems: The number of elements in the allocated
246 * array for both the cur and new values. So @p_array is actually
247 * sized for 2 * @p_array_alloc_elems * @elem_size. Only valid if
248 * @is_array is true.
249 * @cur: Structure to store the current value.
250 * @cur.val: The control's current value, if the @type is represented via
251 * a u32 integer (see &enum v4l2_ctrl_type).
252 * @val: The control's new s32 value.
253 * @p_def: The control's default value represented via a union which
254 * provides a standard way of accessing control types
255 * through a pointer (for compound controls only).
256 * @p_min: The control's minimum value represented via a union which
257 * provides a standard way of accessing control types
258 * through a pointer (for compound controls only).
259 * @p_max: The control's maximum value represented via a union which
260 * provides a standard way of accessing control types
261 * through a pointer (for compound controls only).
262 * @p_cur: The control's current value represented via a union which
263 * provides a standard way of accessing control types
264 * through a pointer.
265 * @p_new: The control's new value represented via a union which provides
266 * a standard way of accessing control types
267 * through a pointer.
268 */
269struct v4l2_ctrl {
270 /* Administrative fields */
271 struct list_head node;
272 struct list_head ev_subs;
273 struct v4l2_ctrl_handler *handler;
274 struct v4l2_ctrl **cluster;
275 unsigned int ncontrols;
276
277 unsigned int done:1;
278
279 unsigned int is_new:1;
280 unsigned int has_changed:1;
281 unsigned int is_private:1;
282 unsigned int is_auto:1;
283 unsigned int is_int:1;
284 unsigned int is_string:1;
285 unsigned int is_ptr:1;
286 unsigned int is_array:1;
287 unsigned int is_dyn_array:1;
288 unsigned int has_volatiles:1;
289 unsigned int call_notify:1;
290 unsigned int manual_mode_value:8;
291
292 const struct v4l2_ctrl_ops *ops;
293 const struct v4l2_ctrl_type_ops *type_ops;
294 u32 id;
295 const char *name;
296 enum v4l2_ctrl_type type;
297 s64 minimum, maximum, default_value;
298 u32 elems;
299 u32 elem_size;
300 u32 new_elems;
301 u32 dims[V4L2_CTRL_MAX_DIMS];
302 u32 nr_of_dims;
303 union {
304 u64 step;
305 u64 menu_skip_mask;
306 };
307 union {
308 const char * const *qmenu;
309 const s64 *qmenu_int;
310 };
311 unsigned long flags;
312 void *priv;
313 void *p_array;
314 u32 p_array_alloc_elems;
315 s32 val;
316 struct {
317 s32 val;
318 } cur;
319
320 union v4l2_ctrl_ptr p_def;
321 union v4l2_ctrl_ptr p_min;
322 union v4l2_ctrl_ptr p_max;
323 union v4l2_ctrl_ptr p_new;
324 union v4l2_ctrl_ptr p_cur;
325};
326
327/**
328 * struct v4l2_ctrl_ref - The control reference.
329 *
330 * @node: List node for the sorted list.
331 * @next: Single-link list node for the hash.
332 * @ctrl: The actual control information.
333 * @helper: Pointer to helper struct. Used internally in
334 * ``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
335 * @from_other_dev: If true, then @ctrl was defined in another
336 * device than the &struct v4l2_ctrl_handler.
337 * @req_done: Internal flag: if the control handler containing this control
338 * reference is bound to a media request, then this is set when
339 * the control has been applied. This prevents applying controls
340 * from a cluster with multiple controls twice (when the first
341 * control of a cluster is applied, they all are).
342 * @p_req_valid: If set, then p_req contains the control value for the request.
343 * @p_req_array_enomem: If set, then p_req is invalid since allocating space for
344 * an array failed. Attempting to read this value shall
345 * result in ENOMEM. Only valid if ctrl->is_array is true.
346 * @p_req_array_alloc_elems: The number of elements allocated for the
347 * array. Only valid if @p_req_valid and ctrl->is_array are
348 * true.
349 * @p_req_elems: The number of elements in @p_req. This is the same as
350 * ctrl->elems, except for dynamic arrays. In that case it is in
351 * the range of 1 to @p_req_array_alloc_elems. Only valid if
352 * @p_req_valid is true.
353 * @p_req: If the control handler containing this control reference
354 * is bound to a media request, then this points to the
355 * value of the control that must be applied when the request
356 * is executed, or to the value of the control at the time
357 * that the request was completed. If @p_req_valid is false,
358 * then this control was never set for this request and the
359 * control will not be updated when this request is applied.
360 *
361 * Each control handler has a list of these refs. The list_head is used to
362 * keep a sorted-by-control-ID list of all controls, while the next pointer
363 * is used to link the control in the hash's bucket.
364 */
365struct v4l2_ctrl_ref {
366 struct list_head node;
367 struct v4l2_ctrl_ref *next;
368 struct v4l2_ctrl *ctrl;
369 struct v4l2_ctrl_helper *helper;
370 bool from_other_dev;
371 bool req_done;
372 bool p_req_valid;
373 bool p_req_array_enomem;
374 u32 p_req_array_alloc_elems;
375 u32 p_req_elems;
376 union v4l2_ctrl_ptr p_req;
377};
378
379/**
380 * struct v4l2_ctrl_handler - The control handler keeps track of all the
381 * controls: both the controls owned by the handler and those inherited
382 * from other handlers.
383 *
384 * @_lock: Default for "lock".
385 * @lock: Lock to control access to this handler and its controls.
386 * May be replaced by the user right after init.
387 * @ctrls: The list of controls owned by this handler.
388 * @ctrl_refs: The list of control references.
389 * @cached: The last found control reference. It is common that the same
390 * control is needed multiple times, so this is a simple
391 * optimization.
392 * @buckets: Buckets for the hashing. Allows for quick control lookup.
393 * @notify: A notify callback that is called whenever the control changes
394 * value.
395 * Note that the handler's lock is held when the notify function
396 * is called!
397 * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
398 * @nr_of_buckets: Total number of buckets in the array.
399 * @error: The error code of the first failed control addition.
400 * @request_is_queued: True if the request was queued.
401 * @requests: List to keep track of open control handler request objects.
402 * For the parent control handler (@req_obj.ops == NULL) this
403 * is the list header. When the parent control handler is
404 * removed, it has to unbind and put all these requests since
405 * they refer to the parent.
406 * @requests_queued: List of the queued requests. This determines the order
407 * in which these controls are applied. Once the request is
408 * completed it is removed from this list.
409 * @req_obj: The &struct media_request_object, used to link into a
410 * &struct media_request. This request object has a refcount.
411 */
412struct v4l2_ctrl_handler {
413 struct mutex _lock;
414 struct mutex *lock;
415 struct list_head ctrls;
416 struct list_head ctrl_refs;
417 struct v4l2_ctrl_ref *cached;
418 struct v4l2_ctrl_ref **buckets;
419 v4l2_ctrl_notify_fnc notify;
420 void *notify_priv;
421 u16 nr_of_buckets;
422 int error;
423 bool request_is_queued;
424 struct list_head requests;
425 struct list_head requests_queued;
426 struct media_request_object req_obj;
427};
428
429/**
430 * struct v4l2_ctrl_config - Control configuration structure.
431 *
432 * @ops: The control ops.
433 * @type_ops: The control type ops. Only needed for compound controls.
434 * @id: The control ID.
435 * @name: The control name.
436 * @type: The control type.
437 * @min: The control's minimum value.
438 * @max: The control's maximum value.
439 * @step: The control's step value for non-menu controls.
440 * @def: The control's default value.
441 * @p_def: The control's default value for compound controls.
442 * @p_min: The control's minimum value for compound controls.
443 * @p_max: The control's maximum value for compound controls.
444 * @dims: The size of each dimension.
445 * @elem_size: The size in bytes of the control.
446 * @flags: The control's flags.
447 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
448 * easy to skip menu items that are not valid. If bit X is set,
449 * then menu item X is skipped. Of course, this only works for
450 * menus with <= 64 menu items. There are no menus that come
451 * close to that number, so this is OK. Should we ever need more,
452 * then this will have to be extended to a bit array.
453 * @qmenu: A const char * array for all menu items. Array entries that are
454 * empty strings ("") correspond to non-existing menu items (this
455 * is in addition to the menu_skip_mask above). The last entry
456 * must be NULL.
457 * @qmenu_int: A const s64 integer array for all menu items of the type
458 * V4L2_CTRL_TYPE_INTEGER_MENU.
459 * @is_private: If set, then this control is private to its handler and it
460 * will not be added to any other handlers.
461 */
462struct v4l2_ctrl_config {
463 const struct v4l2_ctrl_ops *ops;
464 const struct v4l2_ctrl_type_ops *type_ops;
465 u32 id;
466 const char *name;
467 enum v4l2_ctrl_type type;
468 s64 min;
469 s64 max;
470 u64 step;
471 s64 def;
472 union v4l2_ctrl_ptr p_def;
473 union v4l2_ctrl_ptr p_min;
474 union v4l2_ctrl_ptr p_max;
475 u32 dims[V4L2_CTRL_MAX_DIMS];
476 u32 elem_size;
477 u32 flags;
478 u64 menu_skip_mask;
479 const char * const *qmenu;
480 const s64 *qmenu_int;
481 unsigned int is_private:1;
482};
483
484/**
485 * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
486 *
487 * @id: ID of the control
488 * @name: pointer to be filled with a string with the name of the control
489 * @type: pointer for storing the type of the control
490 * @min: pointer for storing the minimum value for the control
491 * @max: pointer for storing the maximum value for the control
492 * @step: pointer for storing the control step
493 * @def: pointer for storing the default value for the control
494 * @flags: pointer for storing the flags to be used on the control
495 *
496 * This works for all standard V4L2 controls.
497 * For non-standard controls it will only fill in the given arguments
498 * and @name content will be set to %NULL.
499 *
500 * This function will overwrite the contents of @name, @type and @flags.
501 * The contents of @min, @max, @step and @def may be modified depending on
502 * the type.
503 *
504 * .. note::
505 *
506 * Do not use in drivers! It is used internally for backwards compatibility
507 * control handling only. Once all drivers are converted to use the new
508 * control framework this function will no longer be exported.
509 */
510void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
511 s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
512
513
514/**
515 * v4l2_ctrl_handler_init_class() - Initialize the control handler.
516 * @hdl: The control handler.
517 * @nr_of_controls_hint: A hint of how many controls this handler is
518 * expected to refer to. This is the total number, so including
519 * any inherited controls. It doesn't have to be precise, but if
520 * it is way off, then you either waste memory (too many buckets
521 * are allocated) or the control lookup becomes slower (not enough
522 * buckets are allocated, so there are more slow list lookups).
523 * It will always work, though.
524 * @key: Used by the lock validator if CONFIG_LOCKDEP is set.
525 * @name: Used by the lock validator if CONFIG_LOCKDEP is set.
526 *
527 * .. attention::
528 *
529 * Never use this call directly, always use the v4l2_ctrl_handler_init()
530 * macro that hides the @key and @name arguments.
531 *
532 * Return: returns an error if the buckets could not be allocated. This
533 * error will also be stored in @hdl->error.
534 */
535int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
536 unsigned int nr_of_controls_hint,
537 struct lock_class_key *key, const char *name);
538
539#ifdef CONFIG_LOCKDEP
540
541/**
542 * v4l2_ctrl_handler_init - helper function to create a static struct
543 * &lock_class_key and calls v4l2_ctrl_handler_init_class()
544 *
545 * @hdl: The control handler.
546 * @nr_of_controls_hint: A hint of how many controls this handler is
547 * expected to refer to. This is the total number, so including
548 * any inherited controls. It doesn't have to be precise, but if
549 * it is way off, then you either waste memory (too many buckets
550 * are allocated) or the control lookup becomes slower (not enough
551 * buckets are allocated, so there are more slow list lookups).
552 * It will always work, though.
553 *
554 * This helper function creates a static struct &lock_class_key and
555 * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
556 * validador.
557 *
558 * Use this helper function to initialize a control handler.
559 */
560#define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \
561( \
562 ({ \
563 static struct lock_class_key _key; \
564 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, \
565 &_key, \
566 KBUILD_BASENAME ":" \
567 __stringify(__LINE__) ":" \
568 "(" #hdl ")->_lock"); \
569 }) \
570)
571#else
572#define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint) \
573 v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
574#endif
575
576/**
577 * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
578 * the control list.
579 * @hdl: The control handler.
580 *
581 * Does nothing if @hdl == NULL.
582 *
583 * Return: @hdl's error field or 0 if @hdl is NULL.
584 */
585int v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
586
587/**
588 * v4l2_ctrl_lock() - Helper function to lock the handler
589 * associated with the control.
590 * @ctrl: The control to lock.
591 */
592static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
593{
594 mutex_lock(ctrl->handler->lock);
595}
596
597/**
598 * v4l2_ctrl_unlock() - Helper function to unlock the handler
599 * associated with the control.
600 * @ctrl: The control to unlock.
601 */
602static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
603{
604 mutex_unlock(ctrl->handler->lock);
605}
606
607/**
608 * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
609 * to the handler to initialize the hardware to the current control values. The
610 * caller is responsible for acquiring the control handler mutex on behalf of
611 * __v4l2_ctrl_handler_setup().
612 * @hdl: The control handler.
613 *
614 * Button controls will be skipped, as are read-only controls.
615 *
616 * If @hdl == NULL, then this just returns 0.
617 */
618int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
619
620/**
621 * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
622 * to the handler to initialize the hardware to the current control values.
623 * @hdl: The control handler.
624 *
625 * Button controls will be skipped, as are read-only controls.
626 *
627 * If @hdl == NULL, then this just returns 0.
628 */
629int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
630
631/**
632 * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
633 * @hdl: The control handler.
634 * @prefix: The prefix to use when logging the control values. If the
635 * prefix does not end with a space, then ": " will be added
636 * after the prefix. If @prefix == NULL, then no prefix will be
637 * used.
638 *
639 * For use with VIDIOC_LOG_STATUS.
640 *
641 * Does nothing if @hdl == NULL.
642 */
643void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
644 const char *prefix);
645
646/**
647 * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
648 * control.
649 *
650 * @hdl: The control handler.
651 * @cfg: The control's configuration data.
652 * @priv: The control's driver-specific private data.
653 *
654 * If the &v4l2_ctrl struct could not be allocated then NULL is returned
655 * and @hdl->error is set to the error code (if it wasn't set already).
656 */
657struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
658 const struct v4l2_ctrl_config *cfg,
659 void *priv);
660
661/**
662 * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
663 * control.
664 *
665 * @hdl: The control handler.
666 * @ops: The control ops.
667 * @id: The control ID.
668 * @min: The control's minimum value.
669 * @max: The control's maximum value.
670 * @step: The control's step value
671 * @def: The control's default value.
672 *
673 * If the &v4l2_ctrl struct could not be allocated, or the control
674 * ID is not known, then NULL is returned and @hdl->error is set to the
675 * appropriate error code (if it wasn't set already).
676 *
677 * If @id refers to a menu control, then this function will return NULL.
678 *
679 * Use v4l2_ctrl_new_std_menu() when adding menu controls.
680 */
681struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
682 const struct v4l2_ctrl_ops *ops,
683 u32 id, s64 min, s64 max, u64 step,
684 s64 def);
685
686/**
687 * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
688 * menu control.
689 *
690 * @hdl: The control handler.
691 * @ops: The control ops.
692 * @id: The control ID.
693 * @max: The control's maximum value.
694 * @mask: The control's skip mask for menu controls. This makes it
695 * easy to skip menu items that are not valid. If bit X is set,
696 * then menu item X is skipped. Of course, this only works for
697 * menus with <= 64 menu items. There are no menus that come
698 * close to that number, so this is OK. Should we ever need more,
699 * then this will have to be extended to a bit array.
700 * @def: The control's default value.
701 *
702 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
703 * determines which menu items are to be skipped.
704 *
705 * If @id refers to a non-menu control, then this function will return NULL.
706 */
707struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
708 const struct v4l2_ctrl_ops *ops,
709 u32 id, u8 max, u64 mask, u8 def);
710
711/**
712 * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
713 * with driver specific menu.
714 *
715 * @hdl: The control handler.
716 * @ops: The control ops.
717 * @id: The control ID.
718 * @max: The control's maximum value.
719 * @mask: The control's skip mask for menu controls. This makes it
720 * easy to skip menu items that are not valid. If bit X is set,
721 * then menu item X is skipped. Of course, this only works for
722 * menus with <= 64 menu items. There are no menus that come
723 * close to that number, so this is OK. Should we ever need more,
724 * then this will have to be extended to a bit array.
725 * @def: The control's default value.
726 * @qmenu: The new menu.
727 *
728 * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
729 * menu of this control.
730 *
731 */
732struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
733 const struct v4l2_ctrl_ops *ops,
734 u32 id, u8 max,
735 u64 mask, u8 def,
736 const char * const *qmenu);
737
738/**
739 * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
740 * compound control.
741 *
742 * @hdl: The control handler.
743 * @ops: The control ops.
744 * @id: The control ID.
745 * @p_def: The control's default value.
746 * @p_min: The control's minimum value.
747 * @p_max: The control's maximum value.
748 *
749 * Same as v4l2_ctrl_new_std(), but with support for compound controls.
750 * To fill in the @p_def, @p_min and @p_max fields, use v4l2_ctrl_ptr_create()
751 * to convert a pointer to a const union v4l2_ctrl_ptr.
752 * Use v4l2_ctrl_ptr_create(NULL) if you want the default, minimum or maximum
753 * value of the compound control to be all zeroes.
754 * If the compound control does not set the ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX``
755 * flag, then it does not has minimum and maximum values. In that case just use
756 * v4l2_ctrl_ptr_create(NULL) for the @p_min and @p_max arguments.
757 *
758 */
759struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
760 const struct v4l2_ctrl_ops *ops,
761 u32 id,
762 const union v4l2_ctrl_ptr p_def,
763 const union v4l2_ctrl_ptr p_min,
764 const union v4l2_ctrl_ptr p_max);
765
766/**
767 * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
768 *
769 * @hdl: The control handler.
770 * @ops: The control ops.
771 * @id: The control ID.
772 * @max: The control's maximum value.
773 * @def: The control's default value.
774 * @qmenu_int: The control's menu entries.
775 *
776 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
777 * takes as an argument an array of integers determining the menu items.
778 *
779 * If @id refers to a non-integer-menu control, then this function will
780 * return %NULL.
781 */
782struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
783 const struct v4l2_ctrl_ops *ops,
784 u32 id, u8 max, u8 def,
785 const s64 *qmenu_int);
786
787/**
788 * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
789 * used when adding a control handler.
790 *
791 * @ctrl: pointer to struct &v4l2_ctrl.
792 */
793
794typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
795
796/**
797 * v4l2_ctrl_add_handler() - Add all controls from handler @add to
798 * handler @hdl.
799 *
800 * @hdl: The control handler.
801 * @add: The control handler whose controls you want to add to
802 * the @hdl control handler.
803 * @filter: This function will filter which controls should be added.
804 * @from_other_dev: If true, then the controls in @add were defined in another
805 * device than @hdl.
806 *
807 * Does nothing if either of the two handlers is a NULL pointer.
808 * If @filter is NULL, then all controls are added. Otherwise only those
809 * controls for which @filter returns true will be added.
810 * In case of an error @hdl->error will be set to the error code (if it
811 * wasn't set already).
812 */
813int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
814 struct v4l2_ctrl_handler *add,
815 v4l2_ctrl_filter filter,
816 bool from_other_dev);
817
818/**
819 * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
820 *
821 * @ctrl: The control that is filtered.
822 *
823 * This will return true for any controls that are valid for radio device
824 * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
825 * transmitter class controls.
826 *
827 * This function is to be used with v4l2_ctrl_add_handler().
828 */
829bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
830
831/**
832 * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
833 * to that cluster.
834 *
835 * @ncontrols: The number of controls in this cluster.
836 * @controls: The cluster control array of size @ncontrols.
837 */
838void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
839
840
841/**
842 * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
843 * to that cluster and set it up for autofoo/foo-type handling.
844 *
845 * @ncontrols: The number of controls in this cluster.
846 * @controls: The cluster control array of size @ncontrols. The first control
847 * must be the 'auto' control (e.g. autogain, autoexposure, etc.)
848 * @manual_val: The value for the first control in the cluster that equals the
849 * manual setting.
850 * @set_volatile: If true, then all controls except the first auto control will
851 * be volatile.
852 *
853 * Use for control groups where one control selects some automatic feature and
854 * the other controls are only active whenever the automatic feature is turned
855 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
856 * red and blue balance, etc.
857 *
858 * The behavior of such controls is as follows:
859 *
860 * When the autofoo control is set to automatic, then any manual controls
861 * are set to inactive and any reads will call g_volatile_ctrl (if the control
862 * was marked volatile).
863 *
864 * When the autofoo control is set to manual, then any manual controls will
865 * be marked active, and any reads will just return the current value without
866 * going through g_volatile_ctrl.
867 *
868 * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
869 * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
870 * if autofoo is in auto mode.
871 */
872void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
873 struct v4l2_ctrl **controls,
874 u8 manual_val, bool set_volatile);
875
876
877/**
878 * v4l2_ctrl_find() - Find a control with the given ID.
879 *
880 * @hdl: The control handler.
881 * @id: The control ID to find.
882 *
883 * If @hdl == NULL this will return NULL as well. Will lock the handler so
884 * do not use from inside &v4l2_ctrl_ops.
885 */
886struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
887
888/**
889 * v4l2_ctrl_activate() - Make the control active or inactive.
890 * @ctrl: The control to (de)activate.
891 * @active: True if the control should become active.
892 *
893 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
894 * Does nothing if @ctrl == NULL.
895 * This will usually be called from within the s_ctrl op.
896 * The V4L2_EVENT_CTRL event will be generated afterwards.
897 *
898 * This function assumes that the control handler is locked.
899 */
900void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
901
902/**
903 * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
904 *
905 * @ctrl: The control to (de)activate.
906 * @grabbed: True if the control should become grabbed.
907 *
908 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
909 * Does nothing if @ctrl == NULL.
910 * The V4L2_EVENT_CTRL event will be generated afterwards.
911 * This will usually be called when starting or stopping streaming in the
912 * driver.
913 *
914 * This function assumes that the control handler is locked by the caller.
915 */
916void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
917
918/**
919 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
920 *
921 * @ctrl: The control to (de)activate.
922 * @grabbed: True if the control should become grabbed.
923 *
924 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
925 * Does nothing if @ctrl == NULL.
926 * The V4L2_EVENT_CTRL event will be generated afterwards.
927 * This will usually be called when starting or stopping streaming in the
928 * driver.
929 *
930 * This function assumes that the control handler is not locked and will
931 * take the lock itself.
932 */
933static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
934{
935 if (!ctrl)
936 return;
937
938 v4l2_ctrl_lock(ctrl);
939 __v4l2_ctrl_grab(ctrl, grabbed);
940 v4l2_ctrl_unlock(ctrl);
941}
942
943/**
944 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
945 *
946 * @ctrl: The control to update.
947 * @min: The control's minimum value.
948 * @max: The control's maximum value.
949 * @step: The control's step value
950 * @def: The control's default value.
951 *
952 * Update the range of a control on the fly. This works for control types
953 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
954 * @step value is interpreted as a menu_skip_mask.
955 *
956 * An error is returned if one of the range arguments is invalid for this
957 * control type.
958 *
959 * The caller is responsible for acquiring the control handler mutex on behalf
960 * of __v4l2_ctrl_modify_range().
961 */
962int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
963 s64 min, s64 max, u64 step, s64 def);
964
965/**
966 * v4l2_ctrl_modify_range() - Update the range of a control.
967 *
968 * @ctrl: The control to update.
969 * @min: The control's minimum value.
970 * @max: The control's maximum value.
971 * @step: The control's step value
972 * @def: The control's default value.
973 *
974 * Update the range of a control on the fly. This works for control types
975 * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
976 * @step value is interpreted as a menu_skip_mask.
977 *
978 * An error is returned if one of the range arguments is invalid for this
979 * control type.
980 *
981 * This function assumes that the control handler is not locked and will
982 * take the lock itself.
983 */
984static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
985 s64 min, s64 max, u64 step, s64 def)
986{
987 int rval;
988
989 v4l2_ctrl_lock(ctrl);
990 rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
991 v4l2_ctrl_unlock(ctrl);
992
993 return rval;
994}
995
996/**
997 *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
998 *
999 * @ctrl: The control to update.
1000 * @dims: The control's new dimensions.
1001 *
1002 * Update the dimensions of an array control on the fly. The elements of the
1003 * array are reset to their default value, even if the dimensions are
1004 * unchanged.
1005 *
1006 * An error is returned if @dims is invalid for this control.
1007 *
1008 * The caller is responsible for acquiring the control handler mutex on behalf
1009 * of __v4l2_ctrl_modify_dimensions().
1010 *
1011 * Note: calling this function when the same control is used in pending requests
1012 * is untested. It should work (a request with the wrong size of the control
1013 * will drop that control silently), but it will be very confusing.
1014 */
1015int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1016 u32 dims[V4L2_CTRL_MAX_DIMS]);
1017
1018/**
1019 * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
1020 *
1021 * @ctrl: The control to update.
1022 * @dims: The control's new dimensions.
1023 *
1024 * Update the dimensions of an array control on the fly. The elements of the
1025 * array are reset to their default value, even if the dimensions are
1026 * unchanged.
1027 *
1028 * An error is returned if @dims is invalid for this control type.
1029 *
1030 * This function assumes that the control handler is not locked and will
1031 * take the lock itself.
1032 *
1033 * Note: calling this function when the same control is used in pending requests
1034 * is untested. It should work (a request with the wrong size of the control
1035 * will drop that control silently), but it will be very confusing.
1036 */
1037static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1038 u32 dims[V4L2_CTRL_MAX_DIMS])
1039{
1040 int rval;
1041
1042 v4l2_ctrl_lock(ctrl);
1043 rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1044 v4l2_ctrl_unlock(ctrl);
1045
1046 return rval;
1047}
1048
1049/**
1050 * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1051 *
1052 * @ctrl: The control.
1053 * @notify: The callback function.
1054 * @priv: The callback private handle, passed as argument to the callback.
1055 *
1056 * This function sets a callback function for the control. If @ctrl is NULL,
1057 * then it will do nothing. If @notify is NULL, then the notify callback will
1058 * be removed.
1059 *
1060 * There can be only one notify. If another already exists, then a WARN_ON
1061 * will be issued and the function will do nothing.
1062 */
1063void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1064 void *priv);
1065
1066/**
1067 * v4l2_ctrl_get_name() - Get the name of the control
1068 *
1069 * @id: The control ID.
1070 *
1071 * This function returns the name of the given control ID or NULL if it isn't
1072 * a known control.
1073 */
1074const char *v4l2_ctrl_get_name(u32 id);
1075
1076/**
1077 * v4l2_ctrl_get_menu() - Get the menu string array of the control
1078 *
1079 * @id: The control ID.
1080 *
1081 * This function returns the NULL-terminated menu string array name of the
1082 * given control ID or NULL if it isn't a known menu control.
1083 */
1084const char * const *v4l2_ctrl_get_menu(u32 id);
1085
1086/**
1087 * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1088 *
1089 * @id: The control ID.
1090 * @len: The size of the integer array.
1091 *
1092 * This function returns the integer array of the given control ID or NULL if it
1093 * if it isn't a known integer menu control.
1094 */
1095const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1096
1097/**
1098 * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1099 * within a driver.
1100 *
1101 * @ctrl: The control.
1102 *
1103 * This returns the control's value 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.
1106 *
1107 * This function is for integer type controls only.
1108 */
1109s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1110
1111/**
1112 * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1113 *
1114 * @ctrl: The control.
1115 * @val: The new value.
1116 *
1117 * This sets the control's new value safely by going through the control
1118 * framework. This function assumes the control's handler is already locked,
1119 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1120 *
1121 * This function is for integer type controls only.
1122 */
1123int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1124
1125/**
1126 * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1127 * within a driver.
1128 * @ctrl: The control.
1129 * @val: The new value.
1130 *
1131 * This sets the control's new value safely by going through the control
1132 * framework. This function will lock the control's handler, so it cannot be
1133 * used from within the &v4l2_ctrl_ops functions.
1134 *
1135 * This function is for integer type controls only.
1136 */
1137static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1138{
1139 int rval;
1140
1141 v4l2_ctrl_lock(ctrl);
1142 rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1143 v4l2_ctrl_unlock(ctrl);
1144
1145 return rval;
1146}
1147
1148/**
1149 * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1150 * from within a driver.
1151 *
1152 * @ctrl: The control.
1153 *
1154 * This returns the control's value safely by going through the control
1155 * framework. This function will lock the control's handler, so it cannot be
1156 * used from within the &v4l2_ctrl_ops functions.
1157 *
1158 * This function is for 64-bit integer type controls only.
1159 */
1160s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1161
1162/**
1163 * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1164 *
1165 * @ctrl: The control.
1166 * @val: The new value.
1167 *
1168 * This sets the control's new value safely by going through the control
1169 * framework. This function assumes the control's handler is already locked,
1170 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1171 *
1172 * This function is for 64-bit integer type controls only.
1173 */
1174int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1175
1176/**
1177 * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1178 * from within a driver.
1179 *
1180 * @ctrl: The control.
1181 * @val: The new value.
1182 *
1183 * This sets the control's new value safely by going through the control
1184 * framework. This function will lock the control's handler, so it cannot be
1185 * used from within the &v4l2_ctrl_ops functions.
1186 *
1187 * This function is for 64-bit integer type controls only.
1188 */
1189static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1190{
1191 int rval;
1192
1193 v4l2_ctrl_lock(ctrl);
1194 rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1195 v4l2_ctrl_unlock(ctrl);
1196
1197 return rval;
1198}
1199
1200/**
1201 * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1202 *
1203 * @ctrl: The control.
1204 * @s: The new string.
1205 *
1206 * This sets the control's new string safely by going through the control
1207 * framework. This function assumes the control's handler is already locked,
1208 * allowing it to be used from within the &v4l2_ctrl_ops functions.
1209 *
1210 * This function is for string type controls only.
1211 */
1212int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1213
1214/**
1215 * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1216 * from within a driver.
1217 *
1218 * @ctrl: The control.
1219 * @s: The new string.
1220 *
1221 * This sets the control's new string safely by going through the control
1222 * framework. This function will lock the control's handler, so it cannot be
1223 * used from within the &v4l2_ctrl_ops functions.
1224 *
1225 * This function is for string type controls only.
1226 */
1227static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1228{
1229 int rval;
1230
1231 v4l2_ctrl_lock(ctrl);
1232 rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1233 v4l2_ctrl_unlock(ctrl);
1234
1235 return rval;
1236}
1237
1238/**
1239 * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1240 *
1241 * @ctrl: The control.
1242 * @type: The type of the data.
1243 * @p: The new compound payload.
1244 *
1245 * This sets the control's new compound payload safely by going through the
1246 * control framework. This function assumes the control's handler is already
1247 * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1248 *
1249 * This function is for compound type controls only.
1250 */
1251int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1252 enum v4l2_ctrl_type type, const void *p);
1253
1254/**
1255 * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1256 * from within a driver.
1257 *
1258 * @ctrl: The control.
1259 * @type: The type of the data.
1260 * @p: The new compound payload.
1261 *
1262 * This sets the control's new compound payload safely by going through the
1263 * control framework. This function will lock the control's handler, so it
1264 * cannot be used from within the &v4l2_ctrl_ops functions.
1265 *
1266 * This function is for compound type controls only.
1267 */
1268static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1269 enum v4l2_ctrl_type type,
1270 const void *p)
1271{
1272 int rval;
1273
1274 v4l2_ctrl_lock(ctrl);
1275 rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1276 v4l2_ctrl_unlock(ctrl);
1277
1278 return rval;
1279}
1280
1281/* Helper defines for area type controls */
1282#define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1283 __v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1284#define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1285 v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1286
1287/* Internal helper functions that deal with control events. */
1288extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1289
1290/**
1291 * v4l2_ctrl_replace - Function to be used as a callback to
1292 * &struct v4l2_subscribed_event_ops replace\(\)
1293 *
1294 * @old: pointer to struct &v4l2_event with the reported
1295 * event;
1296 * @new: pointer to struct &v4l2_event with the modified
1297 * event;
1298 */
1299void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1300
1301/**
1302 * v4l2_ctrl_merge - Function to be used as a callback to
1303 * &struct v4l2_subscribed_event_ops merge(\)
1304 *
1305 * @old: pointer to struct &v4l2_event with the reported
1306 * event;
1307 * @new: pointer to struct &v4l2_event with the merged
1308 * event;
1309 */
1310void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1311
1312/**
1313 * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1314 *
1315 * @file: pointer to struct file
1316 * @priv: unused. Kept just to be compatible to the arguments expected by
1317 * &struct v4l2_ioctl_ops.vidioc_log_status.
1318 *
1319 * Can be used as a vidioc_log_status function that just dumps all controls
1320 * associated with the filehandle.
1321 */
1322int v4l2_ctrl_log_status(struct file *file, void *priv);
1323
1324/**
1325 * v4l2_ctrl_subscribe_event - Subscribes to an event
1326 *
1327 *
1328 * @fh: pointer to struct v4l2_fh
1329 * @sub: pointer to &struct v4l2_event_subscription
1330 *
1331 * Can be used as a vidioc_subscribe_event function that just subscribes
1332 * control events.
1333 */
1334int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1335 const struct v4l2_event_subscription *sub);
1336
1337/**
1338 * v4l2_ctrl_poll - function to be used as a callback to the poll()
1339 * That just polls for control events.
1340 *
1341 * @file: pointer to struct file
1342 * @wait: pointer to struct poll_table_struct
1343 */
1344__poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1345
1346/**
1347 * v4l2_ctrl_request_setup - helper function to apply control values in a request
1348 *
1349 * @req: The request
1350 * @parent: The parent control handler ('priv' in media_request_object_find())
1351 *
1352 * This is a helper function to call the control handler's s_ctrl callback with
1353 * the control values contained in the request. Do note that this approach of
1354 * applying control values in a request is only applicable to memory-to-memory
1355 * devices.
1356 */
1357int v4l2_ctrl_request_setup(struct media_request *req,
1358 struct v4l2_ctrl_handler *parent);
1359
1360/**
1361 * v4l2_ctrl_request_complete - Complete a control handler request object
1362 *
1363 * @req: The request
1364 * @parent: The parent control handler ('priv' in media_request_object_find())
1365 *
1366 * This function is to be called on each control handler that may have had a
1367 * request object associated with it, i.e. control handlers of a driver that
1368 * supports requests.
1369 *
1370 * The function first obtains the values of any volatile controls in the control
1371 * handler and attach them to the request. Then, the function completes the
1372 * request object.
1373 */
1374void v4l2_ctrl_request_complete(struct media_request *req,
1375 struct v4l2_ctrl_handler *parent);
1376
1377/**
1378 * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1379 *
1380 * @req: The request
1381 * @parent: The parent control handler ('priv' in media_request_object_find())
1382 *
1383 * This function finds the control handler in the request. It may return
1384 * NULL if not found. When done, you must call v4l2_ctrl_request_hdl_put()
1385 * with the returned handler pointer.
1386 *
1387 * If the request is not in state VALIDATING or QUEUED, then this function
1388 * will always return NULL.
1389 *
1390 * Note that in state VALIDATING the req_queue_mutex is held, so
1391 * no objects can be added or deleted from the request.
1392 *
1393 * In state QUEUED it is the driver that will have to ensure this.
1394 */
1395struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1396 struct v4l2_ctrl_handler *parent);
1397
1398/**
1399 * v4l2_ctrl_request_hdl_put - Put the control handler
1400 *
1401 * @hdl: Put this control handler
1402 *
1403 * This function released the control handler previously obtained from'
1404 * v4l2_ctrl_request_hdl_find().
1405 */
1406static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1407{
1408 if (hdl)
1409 media_request_object_put(&hdl->req_obj);
1410}
1411
1412/**
1413 * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1414 *
1415 * @hdl: The control handler from the request.
1416 * @id: The ID of the control to find.
1417 *
1418 * This function returns a pointer to the control if this control is
1419 * part of the request or NULL otherwise.
1420 */
1421struct v4l2_ctrl *
1422v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1423
1424/* Helpers for ioctl_ops */
1425
1426/**
1427 * v4l2_queryctrl - Helper function to implement
1428 * :ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1429 *
1430 * @hdl: pointer to &struct v4l2_ctrl_handler
1431 * @qc: pointer to &struct v4l2_queryctrl
1432 *
1433 * If hdl == NULL then they will all return -EINVAL.
1434 */
1435int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1436
1437/**
1438 * v4l2_query_ext_ctrl_to_v4l2_queryctrl - Convert a qec to qe.
1439 *
1440 * @to: The v4l2_queryctrl to write to.
1441 * @from: The v4l2_query_ext_ctrl to read from.
1442 *
1443 * This function is a helper to convert a v4l2_query_ext_ctrl into a
1444 * v4l2_queryctrl.
1445 */
1446void v4l2_query_ext_ctrl_to_v4l2_queryctrl(struct v4l2_queryctrl *to,
1447 const struct v4l2_query_ext_ctrl *from);
1448
1449/**
1450 * v4l2_query_ext_ctrl - Helper function to implement
1451 * :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1452 *
1453 * @hdl: pointer to &struct v4l2_ctrl_handler
1454 * @qc: pointer to &struct v4l2_query_ext_ctrl
1455 *
1456 * If hdl == NULL then they will all return -EINVAL.
1457 */
1458int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1459 struct v4l2_query_ext_ctrl *qc);
1460
1461/**
1462 * v4l2_querymenu - Helper function to implement
1463 * :ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1464 *
1465 * @hdl: pointer to &struct v4l2_ctrl_handler
1466 * @qm: pointer to &struct v4l2_querymenu
1467 *
1468 * If hdl == NULL then they will all return -EINVAL.
1469 */
1470int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1471
1472/**
1473 * v4l2_g_ctrl - Helper function to implement
1474 * :ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1475 *
1476 * @hdl: pointer to &struct v4l2_ctrl_handler
1477 * @ctrl: pointer to &struct v4l2_control
1478 *
1479 * If hdl == NULL then they will all return -EINVAL.
1480 */
1481int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1482
1483/**
1484 * v4l2_s_ctrl - Helper function to implement
1485 * :ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1486 *
1487 * @fh: pointer to &struct v4l2_fh
1488 * @hdl: pointer to &struct v4l2_ctrl_handler
1489 *
1490 * @ctrl: pointer to &struct v4l2_control
1491 *
1492 * If hdl == NULL then they will all return -EINVAL.
1493 */
1494int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1495 struct v4l2_control *ctrl);
1496
1497/**
1498 * v4l2_g_ext_ctrls - Helper function to implement
1499 * :ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1500 *
1501 * @hdl: pointer to &struct v4l2_ctrl_handler
1502 * @vdev: pointer to &struct video_device
1503 * @mdev: pointer to &struct media_device
1504 * @c: pointer to &struct v4l2_ext_controls
1505 *
1506 * If hdl == NULL then they will all return -EINVAL.
1507 */
1508int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1509 struct media_device *mdev, struct v4l2_ext_controls *c);
1510
1511/**
1512 * v4l2_try_ext_ctrls - Helper function to implement
1513 * :ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1514 *
1515 * @hdl: pointer to &struct v4l2_ctrl_handler
1516 * @vdev: pointer to &struct video_device
1517 * @mdev: pointer to &struct media_device
1518 * @c: pointer to &struct v4l2_ext_controls
1519 *
1520 * If hdl == NULL then they will all return -EINVAL.
1521 */
1522int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1523 struct video_device *vdev,
1524 struct media_device *mdev,
1525 struct v4l2_ext_controls *c);
1526
1527/**
1528 * v4l2_s_ext_ctrls - Helper function to implement
1529 * :ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1530 *
1531 * @fh: pointer to &struct v4l2_fh
1532 * @hdl: pointer to &struct v4l2_ctrl_handler
1533 * @vdev: pointer to &struct video_device
1534 * @mdev: pointer to &struct media_device
1535 * @c: pointer to &struct v4l2_ext_controls
1536 *
1537 * If hdl == NULL then they will all return -EINVAL.
1538 */
1539int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1540 struct video_device *vdev,
1541 struct media_device *mdev,
1542 struct v4l2_ext_controls *c);
1543
1544/**
1545 * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1546 * as a &struct v4l2_subdev_core_ops subscribe_event function
1547 * that just subscribes control events.
1548 *
1549 * @sd: pointer to &struct v4l2_subdev
1550 * @fh: pointer to &struct v4l2_fh
1551 * @sub: pointer to &struct v4l2_event_subscription
1552 */
1553int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1554 struct v4l2_event_subscription *sub);
1555
1556/**
1557 * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1558 * handler.
1559 *
1560 * @sd: pointer to &struct v4l2_subdev
1561 */
1562int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1563
1564/**
1565 * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1566 * properties
1567 *
1568 * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1569 * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1570 * @p: pointer to &struct v4l2_fwnode_device_properties
1571 *
1572 * This function registers controls associated to device properties, using the
1573 * property values contained in @p parameter, if the property has been set to
1574 * a value.
1575 *
1576 * Currently the following v4l2 controls are parsed and registered:
1577 * - V4L2_CID_CAMERA_ORIENTATION
1578 * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1579 *
1580 * Controls already registered by the caller with the @hdl control handler are
1581 * not overwritten. Callers should register the controls they want to handle
1582 * themselves before calling this function.
1583 *
1584 * This function will set the control handler's error field on failure, just as
1585 * other functions adding controls to the handler.
1586 *
1587 * Return: 0 on success, a negative error code on failure.
1588 */
1589int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1590 const struct v4l2_ctrl_ops *ctrl_ops,
1591 const struct v4l2_fwnode_device_properties *p);
1592
1593/**
1594 * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1595 *
1596 * @ctrl: The v4l2_ctrl pointer.
1597 * @ptr1: A v4l2 control value.
1598 * @ptr2: A v4l2 control value.
1599 *
1600 * Return: true if values are equal, otherwise false.
1601 */
1602bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl,
1603 union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1604
1605/**
1606 * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1607 *
1608 * @ctrl: The v4l2_ctrl pointer.
1609 * @from_idx: Starting element index.
1610 * @ptr: The v4l2 control value.
1611 *
1612 * Return: void
1613 */
1614void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1615 union v4l2_ctrl_ptr ptr);
1616
1617/**
1618 * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1619 *
1620 * @ctrl: The v4l2_ctrl pointer.
1621 *
1622 * Return: void
1623 */
1624void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1625
1626/**
1627 * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1628 *
1629 * @ctrl: The v4l2_ctrl pointer.
1630 * @ptr: The v4l2 control value.
1631 *
1632 * Return: 0 on success, a negative error code on failure.
1633 */
1634int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1635
1636#endif