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_rect:			Pointer to a rectangle.
60  * @p:				Pointer to a compound value.
61  * @p_const:			Pointer to a constant compound value.
62  */
63 union 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  */
v4l2_ctrl_ptr_create(void * ptr)103 static 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  */
124 struct 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  */
142 struct 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  */
165 typedef 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  */
269 struct 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  */
365 struct 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  */
412 struct 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  */
462 struct 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  */
510 void 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  */
535 int 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 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
584 
585 /**
586  * v4l2_ctrl_lock() - Helper function to lock the handler
587  * associated with the control.
588  * @ctrl:	The control to lock.
589  */
v4l2_ctrl_lock(struct v4l2_ctrl * ctrl)590 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
591 {
592 	mutex_lock(ctrl->handler->lock);
593 }
594 
595 /**
596  * v4l2_ctrl_unlock() - Helper function to unlock the handler
597  * associated with the control.
598  * @ctrl:	The control to unlock.
599  */
v4l2_ctrl_unlock(struct v4l2_ctrl * ctrl)600 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
601 {
602 	mutex_unlock(ctrl->handler->lock);
603 }
604 
605 /**
606  * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
607  * to the handler to initialize the hardware to the current control values. The
608  * caller is responsible for acquiring the control handler mutex on behalf of
609  * __v4l2_ctrl_handler_setup().
610  * @hdl:	The control handler.
611  *
612  * Button controls will be skipped, as are read-only controls.
613  *
614  * If @hdl == NULL, then this just returns 0.
615  */
616 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
617 
618 /**
619  * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
620  * to the handler to initialize the hardware to the current control values.
621  * @hdl:	The control handler.
622  *
623  * Button controls will be skipped, as are read-only controls.
624  *
625  * If @hdl == NULL, then this just returns 0.
626  */
627 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
628 
629 /**
630  * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
631  * @hdl:	The control handler.
632  * @prefix:	The prefix to use when logging the control values. If the
633  *		prefix does not end with a space, then ": " will be added
634  *		after the prefix. If @prefix == NULL, then no prefix will be
635  *		used.
636  *
637  * For use with VIDIOC_LOG_STATUS.
638  *
639  * Does nothing if @hdl == NULL.
640  */
641 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
642 				  const char *prefix);
643 
644 /**
645  * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
646  *	control.
647  *
648  * @hdl:	The control handler.
649  * @cfg:	The control's configuration data.
650  * @priv:	The control's driver-specific private data.
651  *
652  * If the &v4l2_ctrl struct could not be allocated then NULL is returned
653  * and @hdl->error is set to the error code (if it wasn't set already).
654  */
655 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
656 				       const struct v4l2_ctrl_config *cfg,
657 				       void *priv);
658 
659 /**
660  * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
661  *	control.
662  *
663  * @hdl:	The control handler.
664  * @ops:	The control ops.
665  * @id:		The control ID.
666  * @min:	The control's minimum value.
667  * @max:	The control's maximum value.
668  * @step:	The control's step value
669  * @def:	The control's default value.
670  *
671  * If the &v4l2_ctrl struct could not be allocated, or the control
672  * ID is not known, then NULL is returned and @hdl->error is set to the
673  * appropriate error code (if it wasn't set already).
674  *
675  * If @id refers to a menu control, then this function will return NULL.
676  *
677  * Use v4l2_ctrl_new_std_menu() when adding menu controls.
678  */
679 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
680 				    const struct v4l2_ctrl_ops *ops,
681 				    u32 id, s64 min, s64 max, u64 step,
682 				    s64 def);
683 
684 /**
685  * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
686  *	menu control.
687  *
688  * @hdl:	The control handler.
689  * @ops:	The control ops.
690  * @id:		The control ID.
691  * @max:	The control's maximum value.
692  * @mask:	The control's skip mask for menu controls. This makes it
693  *		easy to skip menu items that are not valid. If bit X is set,
694  *		then menu item X is skipped. Of course, this only works for
695  *		menus with <= 64 menu items. There are no menus that come
696  *		close to that number, so this is OK. Should we ever need more,
697  *		then this will have to be extended to a bit array.
698  * @def:	The control's default value.
699  *
700  * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
701  * determines which menu items are to be skipped.
702  *
703  * If @id refers to a non-menu control, then this function will return NULL.
704  */
705 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
706 					 const struct v4l2_ctrl_ops *ops,
707 					 u32 id, u8 max, u64 mask, u8 def);
708 
709 /**
710  * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
711  *	with driver specific menu.
712  *
713  * @hdl:	The control handler.
714  * @ops:	The control ops.
715  * @id:	The control ID.
716  * @max:	The control's maximum value.
717  * @mask:	The control's skip mask for menu controls. This makes it
718  *		easy to skip menu items that are not valid. If bit X is set,
719  *		then menu item X is skipped. Of course, this only works for
720  *		menus with <= 64 menu items. There are no menus that come
721  *		close to that number, so this is OK. Should we ever need more,
722  *		then this will have to be extended to a bit array.
723  * @def:	The control's default value.
724  * @qmenu:	The new menu.
725  *
726  * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
727  * menu of this control.
728  *
729  */
730 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
731 					       const struct v4l2_ctrl_ops *ops,
732 					       u32 id, u8 max,
733 					       u64 mask, u8 def,
734 					       const char * const *qmenu);
735 
736 /**
737  * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
738  *      compound control.
739  *
740  * @hdl:       The control handler.
741  * @ops:       The control ops.
742  * @id:        The control ID.
743  * @p_def:     The control's default value.
744  * @p_min:     The control's minimum value.
745  * @p_max:     The control's maximum value.
746  *
747  * Same as v4l2_ctrl_new_std(), but with support for compound controls.
748  * To fill in the @p_def, @p_min and @p_max fields, use v4l2_ctrl_ptr_create()
749  * to convert a pointer to a const union v4l2_ctrl_ptr.
750  * Use v4l2_ctrl_ptr_create(NULL) if you want the default, minimum or maximum
751  * value of the compound control to be all zeroes.
752  * If the compound control does not set the ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX``
753  * flag, then it does not has minimum and maximum values. In that case just use
754  * v4l2_ctrl_ptr_create(NULL) for the @p_min and @p_max arguments.
755  *
756  */
757 struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
758 					     const struct v4l2_ctrl_ops *ops,
759 					     u32 id,
760 					     const union v4l2_ctrl_ptr p_def,
761 					     const union v4l2_ctrl_ptr p_min,
762 					     const union v4l2_ctrl_ptr p_max);
763 
764 /**
765  * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
766  *
767  * @hdl:	The control handler.
768  * @ops:	The control ops.
769  * @id:	The control ID.
770  * @max:	The control's maximum value.
771  * @def:	The control's default value.
772  * @qmenu_int:	The control's menu entries.
773  *
774  * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
775  * takes as an argument an array of integers determining the menu items.
776  *
777  * If @id refers to a non-integer-menu control, then this function will
778  * return %NULL.
779  */
780 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
781 					 const struct v4l2_ctrl_ops *ops,
782 					 u32 id, u8 max, u8 def,
783 					 const s64 *qmenu_int);
784 
785 /**
786  * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
787  *	used when adding a control handler.
788  *
789  * @ctrl: pointer to struct &v4l2_ctrl.
790  */
791 
792 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
793 
794 /**
795  * v4l2_ctrl_add_handler() - Add all controls from handler @add to
796  *	handler @hdl.
797  *
798  * @hdl:	The control handler.
799  * @add:	The control handler whose controls you want to add to
800  *		the @hdl control handler.
801  * @filter:	This function will filter which controls should be added.
802  * @from_other_dev: If true, then the controls in @add were defined in another
803  *		device than @hdl.
804  *
805  * Does nothing if either of the two handlers is a NULL pointer.
806  * If @filter is NULL, then all controls are added. Otherwise only those
807  * controls for which @filter returns true will be added.
808  * In case of an error @hdl->error will be set to the error code (if it
809  * wasn't set already).
810  */
811 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
812 			  struct v4l2_ctrl_handler *add,
813 			  v4l2_ctrl_filter filter,
814 			  bool from_other_dev);
815 
816 /**
817  * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
818  *
819  * @ctrl:	The control that is filtered.
820  *
821  * This will return true for any controls that are valid for radio device
822  * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
823  * transmitter class controls.
824  *
825  * This function is to be used with v4l2_ctrl_add_handler().
826  */
827 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
828 
829 /**
830  * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
831  *	to that cluster.
832  *
833  * @ncontrols:	The number of controls in this cluster.
834  * @controls:	The cluster control array of size @ncontrols.
835  */
836 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
837 
838 
839 /**
840  * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
841  *	to that cluster and set it up for autofoo/foo-type handling.
842  *
843  * @ncontrols:	The number of controls in this cluster.
844  * @controls:	The cluster control array of size @ncontrols. The first control
845  *		must be the 'auto' control (e.g. autogain, autoexposure, etc.)
846  * @manual_val: The value for the first control in the cluster that equals the
847  *		manual setting.
848  * @set_volatile: If true, then all controls except the first auto control will
849  *		be volatile.
850  *
851  * Use for control groups where one control selects some automatic feature and
852  * the other controls are only active whenever the automatic feature is turned
853  * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
854  * red and blue balance, etc.
855  *
856  * The behavior of such controls is as follows:
857  *
858  * When the autofoo control is set to automatic, then any manual controls
859  * are set to inactive and any reads will call g_volatile_ctrl (if the control
860  * was marked volatile).
861  *
862  * When the autofoo control is set to manual, then any manual controls will
863  * be marked active, and any reads will just return the current value without
864  * going through g_volatile_ctrl.
865  *
866  * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
867  * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
868  * if autofoo is in auto mode.
869  */
870 void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
871 			    struct v4l2_ctrl **controls,
872 			    u8 manual_val, bool set_volatile);
873 
874 
875 /**
876  * v4l2_ctrl_find() - Find a control with the given ID.
877  *
878  * @hdl:	The control handler.
879  * @id:	The control ID to find.
880  *
881  * If @hdl == NULL this will return NULL as well. Will lock the handler so
882  * do not use from inside &v4l2_ctrl_ops.
883  */
884 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
885 
886 /**
887  * v4l2_ctrl_activate() - Make the control active or inactive.
888  * @ctrl:	The control to (de)activate.
889  * @active:	True if the control should become active.
890  *
891  * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
892  * Does nothing if @ctrl == NULL.
893  * This will usually be called from within the s_ctrl op.
894  * The V4L2_EVENT_CTRL event will be generated afterwards.
895  *
896  * This function assumes that the control handler is locked.
897  */
898 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
899 
900 /**
901  * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
902  *
903  * @ctrl:	The control to (de)activate.
904  * @grabbed:	True if the control should become grabbed.
905  *
906  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
907  * Does nothing if @ctrl == NULL.
908  * The V4L2_EVENT_CTRL event will be generated afterwards.
909  * This will usually be called when starting or stopping streaming in the
910  * driver.
911  *
912  * This function assumes that the control handler is locked by the caller.
913  */
914 void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
915 
916 /**
917  * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
918  *
919  * @ctrl:	The control to (de)activate.
920  * @grabbed:	True if the control should become grabbed.
921  *
922  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
923  * Does nothing if @ctrl == NULL.
924  * The V4L2_EVENT_CTRL event will be generated afterwards.
925  * This will usually be called when starting or stopping streaming in the
926  * driver.
927  *
928  * This function assumes that the control handler is not locked and will
929  * take the lock itself.
930  */
v4l2_ctrl_grab(struct v4l2_ctrl * ctrl,bool grabbed)931 static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
932 {
933 	if (!ctrl)
934 		return;
935 
936 	v4l2_ctrl_lock(ctrl);
937 	__v4l2_ctrl_grab(ctrl, grabbed);
938 	v4l2_ctrl_unlock(ctrl);
939 }
940 
941 /**
942  *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
943  *
944  * @ctrl:	The control to update.
945  * @min:	The control's minimum value.
946  * @max:	The control's maximum value.
947  * @step:	The control's step value
948  * @def:	The control's default value.
949  *
950  * Update the range of a control on the fly. This works for control types
951  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
952  * @step value is interpreted as a menu_skip_mask.
953  *
954  * An error is returned if one of the range arguments is invalid for this
955  * control type.
956  *
957  * The caller is responsible for acquiring the control handler mutex on behalf
958  * of __v4l2_ctrl_modify_range().
959  */
960 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
961 			     s64 min, s64 max, u64 step, s64 def);
962 
963 /**
964  * v4l2_ctrl_modify_range() - Update the range of a control.
965  *
966  * @ctrl:	The control to update.
967  * @min:	The control's minimum value.
968  * @max:	The control's maximum value.
969  * @step:	The control's step value
970  * @def:	The control's default value.
971  *
972  * Update the range of a control on the fly. This works for control types
973  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
974  * @step value is interpreted as a menu_skip_mask.
975  *
976  * An error is returned if one of the range arguments is invalid for this
977  * control type.
978  *
979  * This function assumes that the control handler is not locked and will
980  * take the lock itself.
981  */
v4l2_ctrl_modify_range(struct v4l2_ctrl * ctrl,s64 min,s64 max,u64 step,s64 def)982 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
983 					 s64 min, s64 max, u64 step, s64 def)
984 {
985 	int rval;
986 
987 	v4l2_ctrl_lock(ctrl);
988 	rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
989 	v4l2_ctrl_unlock(ctrl);
990 
991 	return rval;
992 }
993 
994 /**
995  *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
996  *
997  * @ctrl:	The control to update.
998  * @dims:	The control's new dimensions.
999  *
1000  * Update the dimensions of an array control on the fly. The elements of the
1001  * array are reset to their default value, even if the dimensions are
1002  * unchanged.
1003  *
1004  * An error is returned if @dims is invalid for this control.
1005  *
1006  * The caller is responsible for acquiring the control handler mutex on behalf
1007  * of __v4l2_ctrl_modify_dimensions().
1008  *
1009  * Note: calling this function when the same control is used in pending requests
1010  * is untested. It should work (a request with the wrong size of the control
1011  * will drop that control silently), but it will be very confusing.
1012  */
1013 int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1014 				  u32 dims[V4L2_CTRL_MAX_DIMS]);
1015 
1016 /**
1017  * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
1018  *
1019  * @ctrl:	The control to update.
1020  * @dims:	The control's new dimensions.
1021  *
1022  * Update the dimensions of an array control on the fly. The elements of the
1023  * array are reset to their default value, even if the dimensions are
1024  * unchanged.
1025  *
1026  * An error is returned if @dims is invalid for this control type.
1027  *
1028  * This function assumes that the control handler is not locked and will
1029  * take the lock itself.
1030  *
1031  * Note: calling this function when the same control is used in pending requests
1032  * is untested. It should work (a request with the wrong size of the control
1033  * will drop that control silently), but it will be very confusing.
1034  */
v4l2_ctrl_modify_dimensions(struct v4l2_ctrl * ctrl,u32 dims[V4L2_CTRL_MAX_DIMS])1035 static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1036 					      u32 dims[V4L2_CTRL_MAX_DIMS])
1037 {
1038 	int rval;
1039 
1040 	v4l2_ctrl_lock(ctrl);
1041 	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1042 	v4l2_ctrl_unlock(ctrl);
1043 
1044 	return rval;
1045 }
1046 
1047 /**
1048  * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1049  *
1050  * @ctrl:	The control.
1051  * @notify:	The callback function.
1052  * @priv:	The callback private handle, passed as argument to the callback.
1053  *
1054  * This function sets a callback function for the control. If @ctrl is NULL,
1055  * then it will do nothing. If @notify is NULL, then the notify callback will
1056  * be removed.
1057  *
1058  * There can be only one notify. If another already exists, then a WARN_ON
1059  * will be issued and the function will do nothing.
1060  */
1061 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1062 		      void *priv);
1063 
1064 /**
1065  * v4l2_ctrl_get_name() - Get the name of the control
1066  *
1067  * @id:		The control ID.
1068  *
1069  * This function returns the name of the given control ID or NULL if it isn't
1070  * a known control.
1071  */
1072 const char *v4l2_ctrl_get_name(u32 id);
1073 
1074 /**
1075  * v4l2_ctrl_get_menu() - Get the menu string array of the control
1076  *
1077  * @id:		The control ID.
1078  *
1079  * This function returns the NULL-terminated menu string array name of the
1080  * given control ID or NULL if it isn't a known menu control.
1081  */
1082 const char * const *v4l2_ctrl_get_menu(u32 id);
1083 
1084 /**
1085  * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1086  *
1087  * @id:		The control ID.
1088  * @len:	The size of the integer array.
1089  *
1090  * This function returns the integer array of the given control ID or NULL if it
1091  * if it isn't a known integer menu control.
1092  */
1093 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1094 
1095 /**
1096  * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1097  *	within a driver.
1098  *
1099  * @ctrl:	The control.
1100  *
1101  * This returns the control's 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 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1108 
1109 /**
1110  * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1111  *
1112  * @ctrl:	The control.
1113  * @val:	The new value.
1114  *
1115  * This sets the control's new value safely by going through the control
1116  * framework. This function assumes the control's handler is already locked,
1117  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1118  *
1119  * This function is for integer type controls only.
1120  */
1121 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1122 
1123 /**
1124  * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1125  *	within a driver.
1126  * @ctrl:	The control.
1127  * @val:	The new value.
1128  *
1129  * This sets the control's new value safely by going through the control
1130  * framework. This function will lock the control's handler, so it cannot be
1131  * used from within the &v4l2_ctrl_ops functions.
1132  *
1133  * This function is for integer type controls only.
1134  */
v4l2_ctrl_s_ctrl(struct v4l2_ctrl * ctrl,s32 val)1135 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1136 {
1137 	int rval;
1138 
1139 	v4l2_ctrl_lock(ctrl);
1140 	rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1141 	v4l2_ctrl_unlock(ctrl);
1142 
1143 	return rval;
1144 }
1145 
1146 /**
1147  * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1148  *	from within a driver.
1149  *
1150  * @ctrl:	The control.
1151  *
1152  * This returns the control's value safely by going through the control
1153  * framework. This function will lock the control's handler, so it cannot be
1154  * used from within the &v4l2_ctrl_ops functions.
1155  *
1156  * This function is for 64-bit integer type controls only.
1157  */
1158 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1159 
1160 /**
1161  * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1162  *
1163  * @ctrl:	The control.
1164  * @val:	The new value.
1165  *
1166  * This sets the control's new value safely by going through the control
1167  * framework. This function assumes the control's handler is already locked,
1168  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1169  *
1170  * This function is for 64-bit integer type controls only.
1171  */
1172 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1173 
1174 /**
1175  * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1176  *	from within a driver.
1177  *
1178  * @ctrl:	The control.
1179  * @val:	The new value.
1180  *
1181  * This sets the control's new value safely by going through the control
1182  * framework. This function will lock the control's handler, so it cannot be
1183  * used from within the &v4l2_ctrl_ops functions.
1184  *
1185  * This function is for 64-bit integer type controls only.
1186  */
v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl * ctrl,s64 val)1187 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1188 {
1189 	int rval;
1190 
1191 	v4l2_ctrl_lock(ctrl);
1192 	rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1193 	v4l2_ctrl_unlock(ctrl);
1194 
1195 	return rval;
1196 }
1197 
1198 /**
1199  * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1200  *
1201  * @ctrl:	The control.
1202  * @s:		The new string.
1203  *
1204  * This sets the control's new string safely by going through the control
1205  * framework. This function assumes the control's handler is already locked,
1206  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1207  *
1208  * This function is for string type controls only.
1209  */
1210 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1211 
1212 /**
1213  * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1214  *	 from within a driver.
1215  *
1216  * @ctrl:	The control.
1217  * @s:		The new string.
1218  *
1219  * This sets the control's new string safely by going through the control
1220  * framework. This function will lock the control's handler, so it cannot be
1221  * used from within the &v4l2_ctrl_ops functions.
1222  *
1223  * This function is for string type controls only.
1224  */
v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl * ctrl,const char * s)1225 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1226 {
1227 	int rval;
1228 
1229 	v4l2_ctrl_lock(ctrl);
1230 	rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1231 	v4l2_ctrl_unlock(ctrl);
1232 
1233 	return rval;
1234 }
1235 
1236 /**
1237  * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1238  *
1239  * @ctrl: The control.
1240  * @type: The type of the data.
1241  * @p:    The new compound payload.
1242  *
1243  * This sets the control's new compound payload safely by going through the
1244  * control framework. This function assumes the control's handler is already
1245  * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1246  *
1247  * This function is for compound type controls only.
1248  */
1249 int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1250 				enum v4l2_ctrl_type type, const void *p);
1251 
1252 /**
1253  * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1254  *	from within a driver.
1255  *
1256  * @ctrl: The control.
1257  * @type: The type of the data.
1258  * @p:    The new compound payload.
1259  *
1260  * This sets the control's new compound payload safely by going through the
1261  * control framework. This function will lock the control's handler, so it
1262  * cannot be used from within the &v4l2_ctrl_ops functions.
1263  *
1264  * This function is for compound type controls only.
1265  */
v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl * ctrl,enum v4l2_ctrl_type type,const void * p)1266 static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1267 					    enum v4l2_ctrl_type type,
1268 					    const void *p)
1269 {
1270 	int rval;
1271 
1272 	v4l2_ctrl_lock(ctrl);
1273 	rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1274 	v4l2_ctrl_unlock(ctrl);
1275 
1276 	return rval;
1277 }
1278 
1279 /* Helper defines for area type controls */
1280 #define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1281 	__v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1282 #define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1283 	v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1284 
1285 /* Internal helper functions that deal with control events. */
1286 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1287 
1288 /**
1289  * v4l2_ctrl_replace - Function to be used as a callback to
1290  *	&struct v4l2_subscribed_event_ops replace\(\)
1291  *
1292  * @old: pointer to struct &v4l2_event with the reported
1293  *	 event;
1294  * @new: pointer to struct &v4l2_event with the modified
1295  *	 event;
1296  */
1297 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1298 
1299 /**
1300  * v4l2_ctrl_merge - Function to be used as a callback to
1301  *	&struct v4l2_subscribed_event_ops merge(\)
1302  *
1303  * @old: pointer to struct &v4l2_event with the reported
1304  *	 event;
1305  * @new: pointer to struct &v4l2_event with the merged
1306  *	 event;
1307  */
1308 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1309 
1310 /**
1311  * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1312  *
1313  * @file: pointer to struct file
1314  * @fh: unused. Kept just to be compatible to the arguments expected by
1315  *	&struct v4l2_ioctl_ops.vidioc_log_status.
1316  *
1317  * Can be used as a vidioc_log_status function that just dumps all controls
1318  * associated with the filehandle.
1319  */
1320 int v4l2_ctrl_log_status(struct file *file, void *fh);
1321 
1322 /**
1323  * v4l2_ctrl_subscribe_event - Subscribes to an event
1324  *
1325  *
1326  * @fh: pointer to struct v4l2_fh
1327  * @sub: pointer to &struct v4l2_event_subscription
1328  *
1329  * Can be used as a vidioc_subscribe_event function that just subscribes
1330  * control events.
1331  */
1332 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1333 				const struct v4l2_event_subscription *sub);
1334 
1335 /**
1336  * v4l2_ctrl_poll - function to be used as a callback to the poll()
1337  *	That just polls for control events.
1338  *
1339  * @file: pointer to struct file
1340  * @wait: pointer to struct poll_table_struct
1341  */
1342 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1343 
1344 /**
1345  * v4l2_ctrl_request_setup - helper function to apply control values in a request
1346  *
1347  * @req: The request
1348  * @parent: The parent control handler ('priv' in media_request_object_find())
1349  *
1350  * This is a helper function to call the control handler's s_ctrl callback with
1351  * the control values contained in the request. Do note that this approach of
1352  * applying control values in a request is only applicable to memory-to-memory
1353  * devices.
1354  */
1355 int v4l2_ctrl_request_setup(struct media_request *req,
1356 			     struct v4l2_ctrl_handler *parent);
1357 
1358 /**
1359  * v4l2_ctrl_request_complete - Complete a control handler request object
1360  *
1361  * @req: The request
1362  * @parent: The parent control handler ('priv' in media_request_object_find())
1363  *
1364  * This function is to be called on each control handler that may have had a
1365  * request object associated with it, i.e. control handlers of a driver that
1366  * supports requests.
1367  *
1368  * The function first obtains the values of any volatile controls in the control
1369  * handler and attach them to the request. Then, the function completes the
1370  * request object.
1371  */
1372 void v4l2_ctrl_request_complete(struct media_request *req,
1373 				struct v4l2_ctrl_handler *parent);
1374 
1375 /**
1376  * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1377  *
1378  * @req: The request
1379  * @parent: The parent control handler ('priv' in media_request_object_find())
1380  *
1381  * This function finds the control handler in the request. It may return
1382  * NULL if not found. When done, you must call v4l2_ctrl_request_hdl_put()
1383  * with the returned handler pointer.
1384  *
1385  * If the request is not in state VALIDATING or QUEUED, then this function
1386  * will always return NULL.
1387  *
1388  * Note that in state VALIDATING the req_queue_mutex is held, so
1389  * no objects can be added or deleted from the request.
1390  *
1391  * In state QUEUED it is the driver that will have to ensure this.
1392  */
1393 struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1394 					struct v4l2_ctrl_handler *parent);
1395 
1396 /**
1397  * v4l2_ctrl_request_hdl_put - Put the control handler
1398  *
1399  * @hdl: Put this control handler
1400  *
1401  * This function released the control handler previously obtained from'
1402  * v4l2_ctrl_request_hdl_find().
1403  */
v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler * hdl)1404 static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1405 {
1406 	if (hdl)
1407 		media_request_object_put(&hdl->req_obj);
1408 }
1409 
1410 /**
1411  * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1412  *
1413  * @hdl: The control handler from the request.
1414  * @id: The ID of the control to find.
1415  *
1416  * This function returns a pointer to the control if this control is
1417  * part of the request or NULL otherwise.
1418  */
1419 struct v4l2_ctrl *
1420 v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1421 
1422 /* Helpers for ioctl_ops */
1423 
1424 /**
1425  * v4l2_queryctrl - Helper function to implement
1426  *	:ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1427  *
1428  * @hdl: pointer to &struct v4l2_ctrl_handler
1429  * @qc: pointer to &struct v4l2_queryctrl
1430  *
1431  * If hdl == NULL then they will all return -EINVAL.
1432  */
1433 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1434 
1435 /**
1436  * v4l2_query_ext_ctrl_to_v4l2_queryctrl - Convert a qec to qe.
1437  *
1438  * @to: The v4l2_queryctrl to write to.
1439  * @from: The v4l2_query_ext_ctrl to read from.
1440  *
1441  * This function is a helper to convert a v4l2_query_ext_ctrl into a
1442  * v4l2_queryctrl.
1443  */
1444 void v4l2_query_ext_ctrl_to_v4l2_queryctrl(struct v4l2_queryctrl *to,
1445 					   const struct v4l2_query_ext_ctrl *from);
1446 
1447 /**
1448  * v4l2_query_ext_ctrl - Helper function to implement
1449  *	 :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1450  *
1451  * @hdl: pointer to &struct v4l2_ctrl_handler
1452  * @qc: pointer to &struct v4l2_query_ext_ctrl
1453  *
1454  * If hdl == NULL then they will all return -EINVAL.
1455  */
1456 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1457 			struct v4l2_query_ext_ctrl *qc);
1458 
1459 /**
1460  * v4l2_querymenu - Helper function to implement
1461  *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1462  *
1463  * @hdl: pointer to &struct v4l2_ctrl_handler
1464  * @qm: pointer to &struct v4l2_querymenu
1465  *
1466  * If hdl == NULL then they will all return -EINVAL.
1467  */
1468 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1469 
1470 /**
1471  * v4l2_g_ctrl - Helper function to implement
1472  *	:ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1473  *
1474  * @hdl: pointer to &struct v4l2_ctrl_handler
1475  * @ctrl: pointer to &struct v4l2_control
1476  *
1477  * If hdl == NULL then they will all return -EINVAL.
1478  */
1479 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1480 
1481 /**
1482  * v4l2_s_ctrl - Helper function to implement
1483  *	:ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1484  *
1485  * @fh: pointer to &struct v4l2_fh
1486  * @hdl: pointer to &struct v4l2_ctrl_handler
1487  *
1488  * @ctrl: pointer to &struct v4l2_control
1489  *
1490  * If hdl == NULL then they will all return -EINVAL.
1491  */
1492 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1493 		struct v4l2_control *ctrl);
1494 
1495 /**
1496  * v4l2_g_ext_ctrls - Helper function to implement
1497  *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1498  *
1499  * @hdl: pointer to &struct v4l2_ctrl_handler
1500  * @vdev: pointer to &struct video_device
1501  * @mdev: pointer to &struct media_device
1502  * @c: pointer to &struct v4l2_ext_controls
1503  *
1504  * If hdl == NULL then they will all return -EINVAL.
1505  */
1506 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1507 		     struct media_device *mdev, struct v4l2_ext_controls *c);
1508 
1509 /**
1510  * v4l2_try_ext_ctrls - Helper function to implement
1511  *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1512  *
1513  * @hdl: pointer to &struct v4l2_ctrl_handler
1514  * @vdev: pointer to &struct video_device
1515  * @mdev: pointer to &struct media_device
1516  * @c: pointer to &struct v4l2_ext_controls
1517  *
1518  * If hdl == NULL then they will all return -EINVAL.
1519  */
1520 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1521 		       struct video_device *vdev,
1522 		       struct media_device *mdev,
1523 		       struct v4l2_ext_controls *c);
1524 
1525 /**
1526  * v4l2_s_ext_ctrls - Helper function to implement
1527  *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1528  *
1529  * @fh: pointer to &struct v4l2_fh
1530  * @hdl: pointer to &struct v4l2_ctrl_handler
1531  * @vdev: pointer to &struct video_device
1532  * @mdev: pointer to &struct media_device
1533  * @c: pointer to &struct v4l2_ext_controls
1534  *
1535  * If hdl == NULL then they will all return -EINVAL.
1536  */
1537 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1538 		     struct video_device *vdev,
1539 		     struct media_device *mdev,
1540 		     struct v4l2_ext_controls *c);
1541 
1542 /**
1543  * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1544  *	as a &struct v4l2_subdev_core_ops subscribe_event function
1545  *	that just subscribes control events.
1546  *
1547  * @sd: pointer to &struct v4l2_subdev
1548  * @fh: pointer to &struct v4l2_fh
1549  * @sub: pointer to &struct v4l2_event_subscription
1550  */
1551 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1552 				     struct v4l2_event_subscription *sub);
1553 
1554 /**
1555  * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1556  *	 handler.
1557  *
1558  * @sd: pointer to &struct v4l2_subdev
1559  */
1560 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1561 
1562 /**
1563  * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1564  *				       properties
1565  *
1566  * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1567  * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1568  * @p: pointer to &struct v4l2_fwnode_device_properties
1569  *
1570  * This function registers controls associated to device properties, using the
1571  * property values contained in @p parameter, if the property has been set to
1572  * a value.
1573  *
1574  * Currently the following v4l2 controls are parsed and registered:
1575  * - V4L2_CID_CAMERA_ORIENTATION
1576  * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1577  *
1578  * Controls already registered by the caller with the @hdl control handler are
1579  * not overwritten. Callers should register the controls they want to handle
1580  * themselves before calling this function.
1581  *
1582  * Return: 0 on success, a negative error code on failure.
1583  */
1584 int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1585 				    const struct v4l2_ctrl_ops *ctrl_ops,
1586 				    const struct v4l2_fwnode_device_properties *p);
1587 
1588 /**
1589  * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1590  *
1591  * @ctrl: The v4l2_ctrl pointer.
1592  * @ptr1: A v4l2 control value.
1593  * @ptr2: A v4l2 control value.
1594  *
1595  * Return: true if values are equal, otherwise false.
1596  */
1597 bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl,
1598 			     union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1599 
1600 /**
1601  * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1602  *
1603  * @ctrl: The v4l2_ctrl pointer.
1604  * @from_idx: Starting element index.
1605  * @ptr: The v4l2 control value.
1606  *
1607  * Return: void
1608  */
1609 void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1610 			    union v4l2_ctrl_ptr ptr);
1611 
1612 /**
1613  * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1614  *
1615  * @ctrl: The v4l2_ctrl pointer.
1616  *
1617  * Return: void
1618  */
1619 void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1620 
1621 /**
1622  * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1623  *
1624  * @ctrl: The v4l2_ctrl pointer.
1625  * @ptr: The v4l2 control value.
1626  *
1627  * Return: 0 on success, a negative error code on failure.
1628  */
1629 int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1630 
1631 #endif
1632