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 */
17 struct file;
18 struct poll_table_struct;
19 struct v4l2_ctrl;
20 struct v4l2_ctrl_handler;
21 struct v4l2_ctrl_helper;
22 struct v4l2_fh;
23 struct v4l2_fwnode_device_properties;
24 struct v4l2_subdev;
25 struct v4l2_subscribed_event;
26 struct 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 */
62 union 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 */
101 static 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 */
122 struct 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 */
138 struct 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 */
157 typedef 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 */
255 struct 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 */
349 struct 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 */
396 struct 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 */
444 struct 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 */
490 void 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 */
515 int 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 */
563 void 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 */
570 static 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 */
580 static 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 */
596 int __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 */
607 int 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 */
621 void 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 */
635 struct 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 */
659 struct 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 */
685 struct 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 */
710 struct 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 */
731 struct 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 */
752 struct 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
764 typedef 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 */
783 int 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 */
799 bool 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 */
808 void 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 */
842 void 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 */
856 struct 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 */
870 void 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 */
886 void __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 */
903 static 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 */
932 int __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 */
954 static 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 */
985 int __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 */
1007 static 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 */
1033 void 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 */
1044 const 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 */
1054 const 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 */
1065 const 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 */
1079 s32 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 */
1093 int __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 */
1107 static 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 */
1130 s64 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 */
1144 int __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 */
1159 static 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 */
1182 int __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 */
1197 static 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 */
1221 int __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 */
1238 static 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. */
1258 extern 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 */
1269 void 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 */
1280 void 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 */
1292 int 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 */
1304 int 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 */
1327 int 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 */
1344 void 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 */
1365 struct 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 */
1376 static 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 */
1391 struct v4l2_ctrl *
1392 v4l2_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 */
1405 int 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 */
1416 int 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 */
1428 int 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 */
1439 int 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 */
1452 int 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 */
1466 int 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 */
1480 int 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 */
1497 int 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 */
1511 int 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 */
1520 int 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 */
1544 int 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 */
1557 bool 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 */
1569 void 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 */
1579 void 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 */
1589 int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1590
1591 #endif
1592
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