xref: /linux/include/media/v4l2-ctrls.h (revision 6c8c1406)
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:				Pointer to a compound value.
56  * @p_const:			Pointer to a constant compound value.
57  */
58 union v4l2_ctrl_ptr {
59 	s32 *p_s32;
60 	s64 *p_s64;
61 	u8 *p_u8;
62 	u16 *p_u16;
63 	u32 *p_u32;
64 	char *p_char;
65 	struct v4l2_ctrl_mpeg2_sequence *p_mpeg2_sequence;
66 	struct v4l2_ctrl_mpeg2_picture *p_mpeg2_picture;
67 	struct v4l2_ctrl_mpeg2_quantisation *p_mpeg2_quantisation;
68 	struct v4l2_ctrl_fwht_params *p_fwht_params;
69 	struct v4l2_ctrl_h264_sps *p_h264_sps;
70 	struct v4l2_ctrl_h264_pps *p_h264_pps;
71 	struct v4l2_ctrl_h264_scaling_matrix *p_h264_scaling_matrix;
72 	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
73 	struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
74 	struct v4l2_ctrl_h264_pred_weights *p_h264_pred_weights;
75 	struct v4l2_ctrl_vp8_frame *p_vp8_frame;
76 	struct v4l2_ctrl_hevc_sps *p_hevc_sps;
77 	struct v4l2_ctrl_hevc_pps *p_hevc_pps;
78 	struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
79 	struct v4l2_ctrl_vp9_compressed_hdr *p_vp9_compressed_hdr_probs;
80 	struct v4l2_ctrl_vp9_frame *p_vp9_frame;
81 	struct v4l2_ctrl_hdr10_cll_info *p_hdr10_cll;
82 	struct v4l2_ctrl_hdr10_mastering_display *p_hdr10_mastering;
83 	struct v4l2_area *p_area;
84 	void *p;
85 	const void *p_const;
86 };
87 
88 /**
89  * v4l2_ctrl_ptr_create() - Helper function to return a v4l2_ctrl_ptr from a
90  * void pointer
91  * @ptr:	The void pointer
92  */
93 static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_create(void *ptr)
94 {
95 	union v4l2_ctrl_ptr p = { .p = ptr };
96 
97 	return p;
98 }
99 
100 /**
101  * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
102  *
103  * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
104  *		for volatile (and usually read-only) controls such as a control
105  *		that returns the current signal strength which changes
106  *		continuously.
107  *		If not set, then the currently cached value will be returned.
108  * @try_ctrl:	Test whether the control's value is valid. Only relevant when
109  *		the usual min/max/step checks are not sufficient.
110  * @s_ctrl:	Actually set the new control value. s_ctrl is compulsory. The
111  *		ctrl->handler->lock is held when these ops are called, so no
112  *		one else can access controls owned by that handler.
113  */
114 struct v4l2_ctrl_ops {
115 	int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
116 	int (*try_ctrl)(struct v4l2_ctrl *ctrl);
117 	int (*s_ctrl)(struct v4l2_ctrl *ctrl);
118 };
119 
120 /**
121  * struct v4l2_ctrl_type_ops - The control type operations that the driver
122  *			       has to provide.
123  *
124  * @equal: return true if all ctrl->elems array elements are equal.
125  * @init: initialize the value for array elements from from_idx to ctrl->elems.
126  * @log: log the value.
127  * @validate: validate the value for ctrl->new_elems array elements.
128  *	Return 0 on success and a negative value otherwise.
129  */
130 struct v4l2_ctrl_type_ops {
131 	bool (*equal)(const struct v4l2_ctrl *ctrl,
132 		      union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
133 	void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx,
134 		     union v4l2_ctrl_ptr ptr);
135 	void (*log)(const struct v4l2_ctrl *ctrl);
136 	int (*validate)(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
137 };
138 
139 /**
140  * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
141  *	that should be called when a control value has changed.
142  *
143  * @ctrl: pointer to struct &v4l2_ctrl
144  * @priv: control private data
145  *
146  * This typedef definition is used as an argument to v4l2_ctrl_notify()
147  * and as an argument at struct &v4l2_ctrl_handler.
148  */
149 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
150 
151 /**
152  * struct v4l2_ctrl - The control structure.
153  *
154  * @node:	The list node.
155  * @ev_subs:	The list of control event subscriptions.
156  * @handler:	The handler that owns the control.
157  * @cluster:	Point to start of cluster array.
158  * @ncontrols:	Number of controls in cluster array.
159  * @done:	Internal flag: set for each processed control.
160  * @is_new:	Set when the user specified a new value for this control. It
161  *		is also set when called from v4l2_ctrl_handler_setup(). Drivers
162  *		should never set this flag.
163  * @has_changed: Set when the current value differs from the new value. Drivers
164  *		should never use this flag.
165  * @is_private: If set, then this control is private to its handler and it
166  *		will not be added to any other handlers. Drivers can set
167  *		this flag.
168  * @is_auto:   If set, then this control selects whether the other cluster
169  *		members are in 'automatic' mode or 'manual' mode. This is
170  *		used for autogain/gain type clusters. Drivers should never
171  *		set this flag directly.
172  * @is_int:    If set, then this control has a simple integer value (i.e. it
173  *		uses ctrl->val).
174  * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
175  * @is_ptr:	If set, then this control is an array and/or has type >=
176  *		%V4L2_CTRL_COMPOUND_TYPES
177  *		and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
178  *		v4l2_ext_control uses field p to point to the data.
179  * @is_array: If set, then this control contains an N-dimensional array.
180  * @is_dyn_array: If set, then this control contains a dynamically sized 1-dimensional array.
181  *		If this is set, then @is_array is also set.
182  * @has_volatiles: If set, then one or more members of the cluster are volatile.
183  *		Drivers should never touch this flag.
184  * @call_notify: If set, then call the handler's notify function whenever the
185  *		control's value changes.
186  * @manual_mode_value: If the is_auto flag is set, then this is the value
187  *		of the auto control that determines if that control is in
188  *		manual mode. So if the value of the auto control equals this
189  *		value, then the whole cluster is in manual mode. Drivers should
190  *		never set this flag directly.
191  * @ops:	The control ops.
192  * @type_ops:	The control type ops.
193  * @id:	The control ID.
194  * @name:	The control name.
195  * @type:	The control type.
196  * @minimum:	The control's minimum value.
197  * @maximum:	The control's maximum value.
198  * @default_value: The control's default value.
199  * @step:	The control's step value for non-menu controls.
200  * @elems:	The number of elements in the N-dimensional array.
201  * @elem_size:	The size in bytes of the control.
202  * @new_elems:	The number of elements in p_new. This is the same as @elems,
203  *		except for dynamic arrays. In that case it is in the range of
204  *		1 to @p_array_alloc_elems.
205  * @dims:	The size of each dimension.
206  * @nr_of_dims:The number of dimensions in @dims.
207  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
208  *		easy to skip menu items that are not valid. If bit X is set,
209  *		then menu item X is skipped. Of course, this only works for
210  *		menus with <= 32 menu items. There are no menus that come
211  *		close to that number, so this is OK. Should we ever need more,
212  *		then this will have to be extended to a u64 or a bit array.
213  * @qmenu:	A const char * array for all menu items. Array entries that are
214  *		empty strings ("") correspond to non-existing menu items (this
215  *		is in addition to the menu_skip_mask above). The last entry
216  *		must be NULL.
217  *		Used only if the @type is %V4L2_CTRL_TYPE_MENU.
218  * @qmenu_int:	A 64-bit integer array for with integer menu items.
219  *		The size of array must be equal to the menu size, e. g.:
220  *		:math:`ceil(\frac{maximum - minimum}{step}) + 1`.
221  *		Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
222  * @flags:	The control's flags.
223  * @priv:	The control's private pointer. For use by the driver. It is
224  *		untouched by the control framework. Note that this pointer is
225  *		not freed when the control is deleted. Should this be needed
226  *		then a new internal bitfield can be added to tell the framework
227  *		to free this pointer.
228  * @p_array:	Pointer to the allocated array. Only valid if @is_array is true.
229  * @p_array_alloc_elems: The number of elements in the allocated
230  *		array for both the cur and new values. So @p_array is actually
231  *		sized for 2 * @p_array_alloc_elems * @elem_size. Only valid if
232  *		@is_array is true.
233  * @cur:	Structure to store the current value.
234  * @cur.val:	The control's current value, if the @type is represented via
235  *		a u32 integer (see &enum v4l2_ctrl_type).
236  * @val:	The control's new s32 value.
237  * @p_def:	The control's default value represented via a union which
238  *		provides a standard way of accessing control types
239  *		through a pointer (for compound controls only).
240  * @p_cur:	The control's current value represented via a union which
241  *		provides a standard way of accessing control types
242  *		through a pointer.
243  * @p_new:	The control's new value represented via a union which provides
244  *		a standard way of accessing control types
245  *		through a pointer.
246  */
247 struct v4l2_ctrl {
248 	/* Administrative fields */
249 	struct list_head node;
250 	struct list_head ev_subs;
251 	struct v4l2_ctrl_handler *handler;
252 	struct v4l2_ctrl **cluster;
253 	unsigned int ncontrols;
254 
255 	unsigned int done:1;
256 
257 	unsigned int is_new:1;
258 	unsigned int has_changed:1;
259 	unsigned int is_private:1;
260 	unsigned int is_auto:1;
261 	unsigned int is_int:1;
262 	unsigned int is_string:1;
263 	unsigned int is_ptr:1;
264 	unsigned int is_array:1;
265 	unsigned int is_dyn_array:1;
266 	unsigned int has_volatiles:1;
267 	unsigned int call_notify:1;
268 	unsigned int manual_mode_value:8;
269 
270 	const struct v4l2_ctrl_ops *ops;
271 	const struct v4l2_ctrl_type_ops *type_ops;
272 	u32 id;
273 	const char *name;
274 	enum v4l2_ctrl_type type;
275 	s64 minimum, maximum, default_value;
276 	u32 elems;
277 	u32 elem_size;
278 	u32 new_elems;
279 	u32 dims[V4L2_CTRL_MAX_DIMS];
280 	u32 nr_of_dims;
281 	union {
282 		u64 step;
283 		u64 menu_skip_mask;
284 	};
285 	union {
286 		const char * const *qmenu;
287 		const s64 *qmenu_int;
288 	};
289 	unsigned long flags;
290 	void *priv;
291 	void *p_array;
292 	u32 p_array_alloc_elems;
293 	s32 val;
294 	struct {
295 		s32 val;
296 	} cur;
297 
298 	union v4l2_ctrl_ptr p_def;
299 	union v4l2_ctrl_ptr p_new;
300 	union v4l2_ctrl_ptr p_cur;
301 };
302 
303 /**
304  * struct v4l2_ctrl_ref - The control reference.
305  *
306  * @node:	List node for the sorted list.
307  * @next:	Single-link list node for the hash.
308  * @ctrl:	The actual control information.
309  * @helper:	Pointer to helper struct. Used internally in
310  *		``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
311  * @from_other_dev: If true, then @ctrl was defined in another
312  *		device than the &struct v4l2_ctrl_handler.
313  * @req_done:	Internal flag: if the control handler containing this control
314  *		reference is bound to a media request, then this is set when
315  *		the control has been applied. This prevents applying controls
316  *		from a cluster with multiple controls twice (when the first
317  *		control of a cluster is applied, they all are).
318  * @p_req_valid: If set, then p_req contains the control value for the request.
319  * @p_req_array_enomem: If set, then p_req is invalid since allocating space for
320  *		an array failed. Attempting to read this value shall
321  *		result in ENOMEM. Only valid if ctrl->is_array is true.
322  * @p_req_array_alloc_elems: The number of elements allocated for the
323  *		array. Only valid if @p_req_valid and ctrl->is_array are
324  *		true.
325  * @p_req_elems: The number of elements in @p_req. This is the same as
326  *		ctrl->elems, except for dynamic arrays. In that case it is in
327  *		the range of 1 to @p_req_array_alloc_elems. Only valid if
328  *		@p_req_valid is true.
329  * @p_req:	If the control handler containing this control reference
330  *		is bound to a media request, then this points to the
331  *		value of the control that must be applied when the request
332  *		is executed, or to the value of the control at the time
333  *		that the request was completed. If @p_req_valid is false,
334  *		then this control was never set for this request and the
335  *		control will not be updated when this request is applied.
336  *
337  * Each control handler has a list of these refs. The list_head is used to
338  * keep a sorted-by-control-ID list of all controls, while the next pointer
339  * is used to link the control in the hash's bucket.
340  */
341 struct v4l2_ctrl_ref {
342 	struct list_head node;
343 	struct v4l2_ctrl_ref *next;
344 	struct v4l2_ctrl *ctrl;
345 	struct v4l2_ctrl_helper *helper;
346 	bool from_other_dev;
347 	bool req_done;
348 	bool p_req_valid;
349 	bool p_req_array_enomem;
350 	u32 p_req_array_alloc_elems;
351 	u32 p_req_elems;
352 	union v4l2_ctrl_ptr p_req;
353 };
354 
355 /**
356  * struct v4l2_ctrl_handler - The control handler keeps track of all the
357  *	controls: both the controls owned by the handler and those inherited
358  *	from other handlers.
359  *
360  * @_lock:	Default for "lock".
361  * @lock:	Lock to control access to this handler and its controls.
362  *		May be replaced by the user right after init.
363  * @ctrls:	The list of controls owned by this handler.
364  * @ctrl_refs:	The list of control references.
365  * @cached:	The last found control reference. It is common that the same
366  *		control is needed multiple times, so this is a simple
367  *		optimization.
368  * @buckets:	Buckets for the hashing. Allows for quick control lookup.
369  * @notify:	A notify callback that is called whenever the control changes
370  *		value.
371  *		Note that the handler's lock is held when the notify function
372  *		is called!
373  * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
374  * @nr_of_buckets: Total number of buckets in the array.
375  * @error:	The error code of the first failed control addition.
376  * @request_is_queued: True if the request was queued.
377  * @requests:	List to keep track of open control handler request objects.
378  *		For the parent control handler (@req_obj.ops == NULL) this
379  *		is the list header. When the parent control handler is
380  *		removed, it has to unbind and put all these requests since
381  *		they refer to the parent.
382  * @requests_queued: List of the queued requests. This determines the order
383  *		in which these controls are applied. Once the request is
384  *		completed it is removed from this list.
385  * @req_obj:	The &struct media_request_object, used to link into a
386  *		&struct media_request. This request object has a refcount.
387  */
388 struct v4l2_ctrl_handler {
389 	struct mutex _lock;
390 	struct mutex *lock;
391 	struct list_head ctrls;
392 	struct list_head ctrl_refs;
393 	struct v4l2_ctrl_ref *cached;
394 	struct v4l2_ctrl_ref **buckets;
395 	v4l2_ctrl_notify_fnc notify;
396 	void *notify_priv;
397 	u16 nr_of_buckets;
398 	int error;
399 	bool request_is_queued;
400 	struct list_head requests;
401 	struct list_head requests_queued;
402 	struct media_request_object req_obj;
403 };
404 
405 /**
406  * struct v4l2_ctrl_config - Control configuration structure.
407  *
408  * @ops:	The control ops.
409  * @type_ops:	The control type ops. Only needed for compound controls.
410  * @id:	The control ID.
411  * @name:	The control name.
412  * @type:	The control type.
413  * @min:	The control's minimum value.
414  * @max:	The control's maximum value.
415  * @step:	The control's step value for non-menu controls.
416  * @def:	The control's default value.
417  * @p_def:	The control's default value for compound controls.
418  * @dims:	The size of each dimension.
419  * @elem_size:	The size in bytes of the control.
420  * @flags:	The control's flags.
421  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
422  *		easy to skip menu items that are not valid. If bit X is set,
423  *		then menu item X is skipped. Of course, this only works for
424  *		menus with <= 64 menu items. There are no menus that come
425  *		close to that number, so this is OK. Should we ever need more,
426  *		then this will have to be extended to a bit array.
427  * @qmenu:	A const char * array for all menu items. Array entries that are
428  *		empty strings ("") correspond to non-existing menu items (this
429  *		is in addition to the menu_skip_mask above). The last entry
430  *		must be NULL.
431  * @qmenu_int:	A const s64 integer array for all menu items of the type
432  *		V4L2_CTRL_TYPE_INTEGER_MENU.
433  * @is_private: If set, then this control is private to its handler and it
434  *		will not be added to any other handlers.
435  */
436 struct v4l2_ctrl_config {
437 	const struct v4l2_ctrl_ops *ops;
438 	const struct v4l2_ctrl_type_ops *type_ops;
439 	u32 id;
440 	const char *name;
441 	enum v4l2_ctrl_type type;
442 	s64 min;
443 	s64 max;
444 	u64 step;
445 	s64 def;
446 	union v4l2_ctrl_ptr p_def;
447 	u32 dims[V4L2_CTRL_MAX_DIMS];
448 	u32 elem_size;
449 	u32 flags;
450 	u64 menu_skip_mask;
451 	const char * const *qmenu;
452 	const s64 *qmenu_int;
453 	unsigned int is_private:1;
454 };
455 
456 /**
457  * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
458  *
459  * @id: ID of the control
460  * @name: pointer to be filled with a string with the name of the control
461  * @type: pointer for storing the type of the control
462  * @min: pointer for storing the minimum value for the control
463  * @max: pointer for storing the maximum value for the control
464  * @step: pointer for storing the control step
465  * @def: pointer for storing the default value for the control
466  * @flags: pointer for storing the flags to be used on the control
467  *
468  * This works for all standard V4L2 controls.
469  * For non-standard controls it will only fill in the given arguments
470  * and @name content will be set to %NULL.
471  *
472  * This function will overwrite the contents of @name, @type and @flags.
473  * The contents of @min, @max, @step and @def may be modified depending on
474  * the type.
475  *
476  * .. note::
477  *
478  *    Do not use in drivers! It is used internally for backwards compatibility
479  *    control handling only. Once all drivers are converted to use the new
480  *    control framework this function will no longer be exported.
481  */
482 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
483 		    s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
484 
485 
486 /**
487  * v4l2_ctrl_handler_init_class() - Initialize the control handler.
488  * @hdl:	The control handler.
489  * @nr_of_controls_hint: A hint of how many controls this handler is
490  *		expected to refer to. This is the total number, so including
491  *		any inherited controls. It doesn't have to be precise, but if
492  *		it is way off, then you either waste memory (too many buckets
493  *		are allocated) or the control lookup becomes slower (not enough
494  *		buckets are allocated, so there are more slow list lookups).
495  *		It will always work, though.
496  * @key:	Used by the lock validator if CONFIG_LOCKDEP is set.
497  * @name:	Used by the lock validator if CONFIG_LOCKDEP is set.
498  *
499  * .. attention::
500  *
501  *    Never use this call directly, always use the v4l2_ctrl_handler_init()
502  *    macro that hides the @key and @name arguments.
503  *
504  * Return: returns an error if the buckets could not be allocated. This
505  * error will also be stored in @hdl->error.
506  */
507 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
508 				 unsigned int nr_of_controls_hint,
509 				 struct lock_class_key *key, const char *name);
510 
511 #ifdef CONFIG_LOCKDEP
512 
513 /**
514  * v4l2_ctrl_handler_init - helper function to create a static struct
515  *	 &lock_class_key and calls v4l2_ctrl_handler_init_class()
516  *
517  * @hdl:	The control handler.
518  * @nr_of_controls_hint: A hint of how many controls this handler is
519  *		expected to refer to. This is the total number, so including
520  *		any inherited controls. It doesn't have to be precise, but if
521  *		it is way off, then you either waste memory (too many buckets
522  *		are allocated) or the control lookup becomes slower (not enough
523  *		buckets are allocated, so there are more slow list lookups).
524  *		It will always work, though.
525  *
526  * This helper function creates a static struct &lock_class_key and
527  * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
528  * validador.
529  *
530  * Use this helper function to initialize a control handler.
531  */
532 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
533 (									\
534 	({								\
535 		static struct lock_class_key _key;			\
536 		v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint,	\
537 					&_key,				\
538 					KBUILD_BASENAME ":"		\
539 					__stringify(__LINE__) ":"	\
540 					"(" #hdl ")->_lock");		\
541 	})								\
542 )
543 #else
544 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
545 	v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
546 #endif
547 
548 /**
549  * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
550  * the control list.
551  * @hdl:	The control handler.
552  *
553  * Does nothing if @hdl == NULL.
554  */
555 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
556 
557 /**
558  * v4l2_ctrl_lock() - Helper function to lock the handler
559  * associated with the control.
560  * @ctrl:	The control to lock.
561  */
562 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
563 {
564 	mutex_lock(ctrl->handler->lock);
565 }
566 
567 /**
568  * v4l2_ctrl_unlock() - Helper function to unlock the handler
569  * associated with the control.
570  * @ctrl:	The control to unlock.
571  */
572 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
573 {
574 	mutex_unlock(ctrl->handler->lock);
575 }
576 
577 /**
578  * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
579  * to the handler to initialize the hardware to the current control values. The
580  * caller is responsible for acquiring the control handler mutex on behalf of
581  * __v4l2_ctrl_handler_setup().
582  * @hdl:	The control handler.
583  *
584  * Button controls will be skipped, as are read-only controls.
585  *
586  * If @hdl == NULL, then this just returns 0.
587  */
588 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
589 
590 /**
591  * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
592  * to the handler to initialize the hardware to the current control values.
593  * @hdl:	The control handler.
594  *
595  * Button controls will be skipped, as are read-only controls.
596  *
597  * If @hdl == NULL, then this just returns 0.
598  */
599 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
600 
601 /**
602  * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
603  * @hdl:	The control handler.
604  * @prefix:	The prefix to use when logging the control values. If the
605  *		prefix does not end with a space, then ": " will be added
606  *		after the prefix. If @prefix == NULL, then no prefix will be
607  *		used.
608  *
609  * For use with VIDIOC_LOG_STATUS.
610  *
611  * Does nothing if @hdl == NULL.
612  */
613 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
614 				  const char *prefix);
615 
616 /**
617  * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
618  *	control.
619  *
620  * @hdl:	The control handler.
621  * @cfg:	The control's configuration data.
622  * @priv:	The control's driver-specific private data.
623  *
624  * If the &v4l2_ctrl struct could not be allocated then NULL is returned
625  * and @hdl->error is set to the error code (if it wasn't set already).
626  */
627 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
628 				       const struct v4l2_ctrl_config *cfg,
629 				       void *priv);
630 
631 /**
632  * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
633  *	control.
634  *
635  * @hdl:	The control handler.
636  * @ops:	The control ops.
637  * @id:		The control ID.
638  * @min:	The control's minimum value.
639  * @max:	The control's maximum value.
640  * @step:	The control's step value
641  * @def:	The control's default value.
642  *
643  * If the &v4l2_ctrl struct could not be allocated, or the control
644  * ID is not known, then NULL is returned and @hdl->error is set to the
645  * appropriate error code (if it wasn't set already).
646  *
647  * If @id refers to a menu control, then this function will return NULL.
648  *
649  * Use v4l2_ctrl_new_std_menu() when adding menu controls.
650  */
651 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
652 				    const struct v4l2_ctrl_ops *ops,
653 				    u32 id, s64 min, s64 max, u64 step,
654 				    s64 def);
655 
656 /**
657  * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
658  *	menu control.
659  *
660  * @hdl:	The control handler.
661  * @ops:	The control ops.
662  * @id:		The control ID.
663  * @max:	The control's maximum value.
664  * @mask:	The control's skip mask for menu controls. This makes it
665  *		easy to skip menu items that are not valid. If bit X is set,
666  *		then menu item X is skipped. Of course, this only works for
667  *		menus with <= 64 menu items. There are no menus that come
668  *		close to that number, so this is OK. Should we ever need more,
669  *		then this will have to be extended to a bit array.
670  * @def:	The control's default value.
671  *
672  * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
673  * determines which menu items are to be skipped.
674  *
675  * If @id refers to a non-menu control, then this function will return NULL.
676  */
677 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
678 					 const struct v4l2_ctrl_ops *ops,
679 					 u32 id, u8 max, u64 mask, u8 def);
680 
681 /**
682  * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
683  *	with driver specific menu.
684  *
685  * @hdl:	The control handler.
686  * @ops:	The control ops.
687  * @id:	The control ID.
688  * @max:	The control's maximum value.
689  * @mask:	The control's skip mask for menu controls. This makes it
690  *		easy to skip menu items that are not valid. If bit X is set,
691  *		then menu item X is skipped. Of course, this only works for
692  *		menus with <= 64 menu items. There are no menus that come
693  *		close to that number, so this is OK. Should we ever need more,
694  *		then this will have to be extended to a bit array.
695  * @def:	The control's default value.
696  * @qmenu:	The new menu.
697  *
698  * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
699  * menu of this control.
700  *
701  */
702 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
703 					       const struct v4l2_ctrl_ops *ops,
704 					       u32 id, u8 max,
705 					       u64 mask, u8 def,
706 					       const char * const *qmenu);
707 
708 /**
709  * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
710  *      compound control.
711  *
712  * @hdl:       The control handler.
713  * @ops:       The control ops.
714  * @id:        The control ID.
715  * @p_def:     The control's default value.
716  *
717  * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
718  * to the @p_def field. Use v4l2_ctrl_ptr_create() to create @p_def from a
719  * pointer. Use v4l2_ctrl_ptr_create(NULL) if the default value of the
720  * compound control should be all zeroes.
721  *
722  */
723 struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
724 					     const struct v4l2_ctrl_ops *ops,
725 					     u32 id,
726 					     const union v4l2_ctrl_ptr p_def);
727 
728 /**
729  * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
730  *
731  * @hdl:	The control handler.
732  * @ops:	The control ops.
733  * @id:	The control ID.
734  * @max:	The control's maximum value.
735  * @def:	The control's default value.
736  * @qmenu_int:	The control's menu entries.
737  *
738  * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
739  * takes as an argument an array of integers determining the menu items.
740  *
741  * If @id refers to a non-integer-menu control, then this function will
742  * return %NULL.
743  */
744 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
745 					 const struct v4l2_ctrl_ops *ops,
746 					 u32 id, u8 max, u8 def,
747 					 const s64 *qmenu_int);
748 
749 /**
750  * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
751  *	used when adding a control handler.
752  *
753  * @ctrl: pointer to struct &v4l2_ctrl.
754  */
755 
756 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
757 
758 /**
759  * v4l2_ctrl_add_handler() - Add all controls from handler @add to
760  *	handler @hdl.
761  *
762  * @hdl:	The control handler.
763  * @add:	The control handler whose controls you want to add to
764  *		the @hdl control handler.
765  * @filter:	This function will filter which controls should be added.
766  * @from_other_dev: If true, then the controls in @add were defined in another
767  *		device than @hdl.
768  *
769  * Does nothing if either of the two handlers is a NULL pointer.
770  * If @filter is NULL, then all controls are added. Otherwise only those
771  * controls for which @filter returns true will be added.
772  * In case of an error @hdl->error will be set to the error code (if it
773  * wasn't set already).
774  */
775 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
776 			  struct v4l2_ctrl_handler *add,
777 			  v4l2_ctrl_filter filter,
778 			  bool from_other_dev);
779 
780 /**
781  * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
782  *
783  * @ctrl:	The control that is filtered.
784  *
785  * This will return true for any controls that are valid for radio device
786  * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
787  * transmitter class controls.
788  *
789  * This function is to be used with v4l2_ctrl_add_handler().
790  */
791 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
792 
793 /**
794  * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
795  *	to that cluster.
796  *
797  * @ncontrols:	The number of controls in this cluster.
798  * @controls:	The cluster control array of size @ncontrols.
799  */
800 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
801 
802 
803 /**
804  * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
805  *	to that cluster and set it up for autofoo/foo-type handling.
806  *
807  * @ncontrols:	The number of controls in this cluster.
808  * @controls:	The cluster control array of size @ncontrols. The first control
809  *		must be the 'auto' control (e.g. autogain, autoexposure, etc.)
810  * @manual_val: The value for the first control in the cluster that equals the
811  *		manual setting.
812  * @set_volatile: If true, then all controls except the first auto control will
813  *		be volatile.
814  *
815  * Use for control groups where one control selects some automatic feature and
816  * the other controls are only active whenever the automatic feature is turned
817  * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
818  * red and blue balance, etc.
819  *
820  * The behavior of such controls is as follows:
821  *
822  * When the autofoo control is set to automatic, then any manual controls
823  * are set to inactive and any reads will call g_volatile_ctrl (if the control
824  * was marked volatile).
825  *
826  * When the autofoo control is set to manual, then any manual controls will
827  * be marked active, and any reads will just return the current value without
828  * going through g_volatile_ctrl.
829  *
830  * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
831  * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
832  * if autofoo is in auto mode.
833  */
834 void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
835 			    struct v4l2_ctrl **controls,
836 			    u8 manual_val, bool set_volatile);
837 
838 
839 /**
840  * v4l2_ctrl_find() - Find a control with the given ID.
841  *
842  * @hdl:	The control handler.
843  * @id:	The control ID to find.
844  *
845  * If @hdl == NULL this will return NULL as well. Will lock the handler so
846  * do not use from inside &v4l2_ctrl_ops.
847  */
848 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
849 
850 /**
851  * v4l2_ctrl_activate() - Make the control active or inactive.
852  * @ctrl:	The control to (de)activate.
853  * @active:	True if the control should become active.
854  *
855  * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
856  * Does nothing if @ctrl == NULL.
857  * This will usually be called from within the s_ctrl op.
858  * The V4L2_EVENT_CTRL event will be generated afterwards.
859  *
860  * This function assumes that the control handler is locked.
861  */
862 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
863 
864 /**
865  * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
866  *
867  * @ctrl:	The control to (de)activate.
868  * @grabbed:	True if the control should become grabbed.
869  *
870  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
871  * Does nothing if @ctrl == NULL.
872  * The V4L2_EVENT_CTRL event will be generated afterwards.
873  * This will usually be called when starting or stopping streaming in the
874  * driver.
875  *
876  * This function assumes that the control handler is locked by the caller.
877  */
878 void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
879 
880 /**
881  * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
882  *
883  * @ctrl:	The control to (de)activate.
884  * @grabbed:	True if the control should become grabbed.
885  *
886  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
887  * Does nothing if @ctrl == NULL.
888  * The V4L2_EVENT_CTRL event will be generated afterwards.
889  * This will usually be called when starting or stopping streaming in the
890  * driver.
891  *
892  * This function assumes that the control handler is not locked and will
893  * take the lock itself.
894  */
895 static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
896 {
897 	if (!ctrl)
898 		return;
899 
900 	v4l2_ctrl_lock(ctrl);
901 	__v4l2_ctrl_grab(ctrl, grabbed);
902 	v4l2_ctrl_unlock(ctrl);
903 }
904 
905 /**
906  *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
907  *
908  * @ctrl:	The control to update.
909  * @min:	The control's minimum value.
910  * @max:	The control's maximum value.
911  * @step:	The control's step value
912  * @def:	The control's default value.
913  *
914  * Update the range of a control on the fly. This works for control types
915  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
916  * @step value is interpreted as a menu_skip_mask.
917  *
918  * An error is returned if one of the range arguments is invalid for this
919  * control type.
920  *
921  * The caller is responsible for acquiring the control handler mutex on behalf
922  * of __v4l2_ctrl_modify_range().
923  */
924 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
925 			     s64 min, s64 max, u64 step, s64 def);
926 
927 /**
928  * v4l2_ctrl_modify_range() - Update the range of a control.
929  *
930  * @ctrl:	The control to update.
931  * @min:	The control's minimum value.
932  * @max:	The control's maximum value.
933  * @step:	The control's step value
934  * @def:	The control's default value.
935  *
936  * Update the range of a control on the fly. This works for control types
937  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
938  * @step value is interpreted as a menu_skip_mask.
939  *
940  * An error is returned if one of the range arguments is invalid for this
941  * control type.
942  *
943  * This function assumes that the control handler is not locked and will
944  * take the lock itself.
945  */
946 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
947 					 s64 min, s64 max, u64 step, s64 def)
948 {
949 	int rval;
950 
951 	v4l2_ctrl_lock(ctrl);
952 	rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
953 	v4l2_ctrl_unlock(ctrl);
954 
955 	return rval;
956 }
957 
958 /**
959  *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
960  *
961  * @ctrl:	The control to update.
962  * @dims:	The control's new dimensions.
963  *
964  * Update the dimensions of an array control on the fly. The elements of the
965  * array are reset to their default value, even if the dimensions are
966  * unchanged.
967  *
968  * An error is returned if @dims is invalid for this control.
969  *
970  * The caller is responsible for acquiring the control handler mutex on behalf
971  * of __v4l2_ctrl_modify_dimensions().
972  *
973  * Note: calling this function when the same control is used in pending requests
974  * is untested. It should work (a request with the wrong size of the control
975  * will drop that control silently), but it will be very confusing.
976  */
977 int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
978 				  u32 dims[V4L2_CTRL_MAX_DIMS]);
979 
980 /**
981  * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
982  *
983  * @ctrl:	The control to update.
984  * @dims:	The control's new dimensions.
985  *
986  * Update the dimensions of an array control on the fly. The elements of the
987  * array are reset to their default value, even if the dimensions are
988  * unchanged.
989  *
990  * An error is returned if @dims is invalid for this control type.
991  *
992  * This function assumes that the control handler is not locked and will
993  * take the lock itself.
994  *
995  * Note: calling this function when the same control is used in pending requests
996  * is untested. It should work (a request with the wrong size of the control
997  * will drop that control silently), but it will be very confusing.
998  */
999 static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1000 					      u32 dims[V4L2_CTRL_MAX_DIMS])
1001 {
1002 	int rval;
1003 
1004 	v4l2_ctrl_lock(ctrl);
1005 	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1006 	v4l2_ctrl_unlock(ctrl);
1007 
1008 	return rval;
1009 }
1010 
1011 /**
1012  * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1013  *
1014  * @ctrl:	The control.
1015  * @notify:	The callback function.
1016  * @priv:	The callback private handle, passed as argument to the callback.
1017  *
1018  * This function sets a callback function for the control. If @ctrl is NULL,
1019  * then it will do nothing. If @notify is NULL, then the notify callback will
1020  * be removed.
1021  *
1022  * There can be only one notify. If another already exists, then a WARN_ON
1023  * will be issued and the function will do nothing.
1024  */
1025 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1026 		      void *priv);
1027 
1028 /**
1029  * v4l2_ctrl_get_name() - Get the name of the control
1030  *
1031  * @id:		The control ID.
1032  *
1033  * This function returns the name of the given control ID or NULL if it isn't
1034  * a known control.
1035  */
1036 const char *v4l2_ctrl_get_name(u32 id);
1037 
1038 /**
1039  * v4l2_ctrl_get_menu() - Get the menu string array of the control
1040  *
1041  * @id:		The control ID.
1042  *
1043  * This function returns the NULL-terminated menu string array name of the
1044  * given control ID or NULL if it isn't a known menu control.
1045  */
1046 const char * const *v4l2_ctrl_get_menu(u32 id);
1047 
1048 /**
1049  * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1050  *
1051  * @id:		The control ID.
1052  * @len:	The size of the integer array.
1053  *
1054  * This function returns the integer array of the given control ID or NULL if it
1055  * if it isn't a known integer menu control.
1056  */
1057 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1058 
1059 /**
1060  * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1061  *	within a driver.
1062  *
1063  * @ctrl:	The control.
1064  *
1065  * This returns the control's value safely by going through the control
1066  * framework. This function will lock the control's handler, so it cannot be
1067  * used from within the &v4l2_ctrl_ops functions.
1068  *
1069  * This function is for integer type controls only.
1070  */
1071 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1072 
1073 /**
1074  * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1075  *
1076  * @ctrl:	The control.
1077  * @val:	The new value.
1078  *
1079  * This sets the control's new value safely by going through the control
1080  * framework. This function assumes the control's handler is already locked,
1081  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1082  *
1083  * This function is for integer type controls only.
1084  */
1085 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1086 
1087 /**
1088  * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1089  *	within a driver.
1090  * @ctrl:	The control.
1091  * @val:	The new value.
1092  *
1093  * This sets the control's new value safely by going through the control
1094  * framework. This function will lock the control's handler, so it cannot be
1095  * used from within the &v4l2_ctrl_ops functions.
1096  *
1097  * This function is for integer type controls only.
1098  */
1099 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1100 {
1101 	int rval;
1102 
1103 	v4l2_ctrl_lock(ctrl);
1104 	rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1105 	v4l2_ctrl_unlock(ctrl);
1106 
1107 	return rval;
1108 }
1109 
1110 /**
1111  * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1112  *	from within a driver.
1113  *
1114  * @ctrl:	The control.
1115  *
1116  * This returns the control's value safely by going through the control
1117  * framework. This function will lock the control's handler, so it cannot be
1118  * used from within the &v4l2_ctrl_ops functions.
1119  *
1120  * This function is for 64-bit integer type controls only.
1121  */
1122 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1123 
1124 /**
1125  * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1126  *
1127  * @ctrl:	The control.
1128  * @val:	The new value.
1129  *
1130  * This sets the control's new value safely by going through the control
1131  * framework. This function assumes the control's handler is already locked,
1132  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1133  *
1134  * This function is for 64-bit integer type controls only.
1135  */
1136 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1137 
1138 /**
1139  * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1140  *	from within a driver.
1141  *
1142  * @ctrl:	The control.
1143  * @val:	The new value.
1144  *
1145  * This sets the control's new value safely by going through the control
1146  * framework. This function will lock the control's handler, so it cannot be
1147  * used from within the &v4l2_ctrl_ops functions.
1148  *
1149  * This function is for 64-bit integer type controls only.
1150  */
1151 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1152 {
1153 	int rval;
1154 
1155 	v4l2_ctrl_lock(ctrl);
1156 	rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1157 	v4l2_ctrl_unlock(ctrl);
1158 
1159 	return rval;
1160 }
1161 
1162 /**
1163  * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1164  *
1165  * @ctrl:	The control.
1166  * @s:		The new string.
1167  *
1168  * This sets the control's new string safely by going through the control
1169  * framework. This function assumes the control's handler is already locked,
1170  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1171  *
1172  * This function is for string type controls only.
1173  */
1174 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1175 
1176 /**
1177  * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1178  *	 from within a driver.
1179  *
1180  * @ctrl:	The control.
1181  * @s:		The new string.
1182  *
1183  * This sets the control's new string safely by going through the control
1184  * framework. This function will lock the control's handler, so it cannot be
1185  * used from within the &v4l2_ctrl_ops functions.
1186  *
1187  * This function is for string type controls only.
1188  */
1189 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1190 {
1191 	int rval;
1192 
1193 	v4l2_ctrl_lock(ctrl);
1194 	rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1195 	v4l2_ctrl_unlock(ctrl);
1196 
1197 	return rval;
1198 }
1199 
1200 /**
1201  * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1202  *
1203  * @ctrl: The control.
1204  * @type: The type of the data.
1205  * @p:    The new compound payload.
1206  *
1207  * This sets the control's new compound payload safely by going through the
1208  * control framework. This function assumes the control's handler is already
1209  * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1210  *
1211  * This function is for compound type controls only.
1212  */
1213 int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1214 				enum v4l2_ctrl_type type, const void *p);
1215 
1216 /**
1217  * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1218  *	from within a driver.
1219  *
1220  * @ctrl: The control.
1221  * @type: The type of the data.
1222  * @p:    The new compound payload.
1223  *
1224  * This sets the control's new compound payload safely by going through the
1225  * control framework. This function will lock the control's handler, so it
1226  * cannot be used from within the &v4l2_ctrl_ops functions.
1227  *
1228  * This function is for compound type controls only.
1229  */
1230 static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1231 					    enum v4l2_ctrl_type type,
1232 					    const void *p)
1233 {
1234 	int rval;
1235 
1236 	v4l2_ctrl_lock(ctrl);
1237 	rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1238 	v4l2_ctrl_unlock(ctrl);
1239 
1240 	return rval;
1241 }
1242 
1243 /* Helper defines for area type controls */
1244 #define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1245 	__v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1246 #define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1247 	v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1248 
1249 /* Internal helper functions that deal with control events. */
1250 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1251 
1252 /**
1253  * v4l2_ctrl_replace - Function to be used as a callback to
1254  *	&struct v4l2_subscribed_event_ops replace\(\)
1255  *
1256  * @old: pointer to struct &v4l2_event with the reported
1257  *	 event;
1258  * @new: pointer to struct &v4l2_event with the modified
1259  *	 event;
1260  */
1261 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1262 
1263 /**
1264  * v4l2_ctrl_merge - Function to be used as a callback to
1265  *	&struct v4l2_subscribed_event_ops merge(\)
1266  *
1267  * @old: pointer to struct &v4l2_event with the reported
1268  *	 event;
1269  * @new: pointer to struct &v4l2_event with the merged
1270  *	 event;
1271  */
1272 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1273 
1274 /**
1275  * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1276  *
1277  * @file: pointer to struct file
1278  * @fh: unused. Kept just to be compatible to the arguments expected by
1279  *	&struct v4l2_ioctl_ops.vidioc_log_status.
1280  *
1281  * Can be used as a vidioc_log_status function that just dumps all controls
1282  * associated with the filehandle.
1283  */
1284 int v4l2_ctrl_log_status(struct file *file, void *fh);
1285 
1286 /**
1287  * v4l2_ctrl_subscribe_event - Subscribes to an event
1288  *
1289  *
1290  * @fh: pointer to struct v4l2_fh
1291  * @sub: pointer to &struct v4l2_event_subscription
1292  *
1293  * Can be used as a vidioc_subscribe_event function that just subscribes
1294  * control events.
1295  */
1296 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1297 				const struct v4l2_event_subscription *sub);
1298 
1299 /**
1300  * v4l2_ctrl_poll - function to be used as a callback to the poll()
1301  *	That just polls for control events.
1302  *
1303  * @file: pointer to struct file
1304  * @wait: pointer to struct poll_table_struct
1305  */
1306 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1307 
1308 /**
1309  * v4l2_ctrl_request_setup - helper function to apply control values in a request
1310  *
1311  * @req: The request
1312  * @parent: The parent control handler ('priv' in media_request_object_find())
1313  *
1314  * This is a helper function to call the control handler's s_ctrl callback with
1315  * the control values contained in the request. Do note that this approach of
1316  * applying control values in a request is only applicable to memory-to-memory
1317  * devices.
1318  */
1319 int v4l2_ctrl_request_setup(struct media_request *req,
1320 			     struct v4l2_ctrl_handler *parent);
1321 
1322 /**
1323  * v4l2_ctrl_request_complete - Complete a control handler request object
1324  *
1325  * @req: The request
1326  * @parent: The parent control handler ('priv' in media_request_object_find())
1327  *
1328  * This function is to be called on each control handler that may have had a
1329  * request object associated with it, i.e. control handlers of a driver that
1330  * supports requests.
1331  *
1332  * The function first obtains the values of any volatile controls in the control
1333  * handler and attach them to the request. Then, the function completes the
1334  * request object.
1335  */
1336 void v4l2_ctrl_request_complete(struct media_request *req,
1337 				struct v4l2_ctrl_handler *parent);
1338 
1339 /**
1340  * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1341  *
1342  * @req: The request
1343  * @parent: The parent control handler ('priv' in media_request_object_find())
1344  *
1345  * This function finds the control handler in the request. It may return
1346  * NULL if not found. When done, you must call v4l2_ctrl_request_put_hdl()
1347  * with the returned handler pointer.
1348  *
1349  * If the request is not in state VALIDATING or QUEUED, then this function
1350  * will always return NULL.
1351  *
1352  * Note that in state VALIDATING the req_queue_mutex is held, so
1353  * no objects can be added or deleted from the request.
1354  *
1355  * In state QUEUED it is the driver that will have to ensure this.
1356  */
1357 struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1358 					struct v4l2_ctrl_handler *parent);
1359 
1360 /**
1361  * v4l2_ctrl_request_hdl_put - Put the control handler
1362  *
1363  * @hdl: Put this control handler
1364  *
1365  * This function released the control handler previously obtained from'
1366  * v4l2_ctrl_request_hdl_find().
1367  */
1368 static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1369 {
1370 	if (hdl)
1371 		media_request_object_put(&hdl->req_obj);
1372 }
1373 
1374 /**
1375  * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1376  *
1377  * @hdl: The control handler from the request.
1378  * @id: The ID of the control to find.
1379  *
1380  * This function returns a pointer to the control if this control is
1381  * part of the request or NULL otherwise.
1382  */
1383 struct v4l2_ctrl *
1384 v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1385 
1386 /* Helpers for ioctl_ops */
1387 
1388 /**
1389  * v4l2_queryctrl - Helper function to implement
1390  *	:ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1391  *
1392  * @hdl: pointer to &struct v4l2_ctrl_handler
1393  * @qc: pointer to &struct v4l2_queryctrl
1394  *
1395  * If hdl == NULL then they will all return -EINVAL.
1396  */
1397 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1398 
1399 /**
1400  * v4l2_query_ext_ctrl - Helper function to implement
1401  *	 :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1402  *
1403  * @hdl: pointer to &struct v4l2_ctrl_handler
1404  * @qc: pointer to &struct v4l2_query_ext_ctrl
1405  *
1406  * If hdl == NULL then they will all return -EINVAL.
1407  */
1408 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1409 			struct v4l2_query_ext_ctrl *qc);
1410 
1411 /**
1412  * v4l2_querymenu - Helper function to implement
1413  *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1414  *
1415  * @hdl: pointer to &struct v4l2_ctrl_handler
1416  * @qm: pointer to &struct v4l2_querymenu
1417  *
1418  * If hdl == NULL then they will all return -EINVAL.
1419  */
1420 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1421 
1422 /**
1423  * v4l2_g_ctrl - Helper function to implement
1424  *	:ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1425  *
1426  * @hdl: pointer to &struct v4l2_ctrl_handler
1427  * @ctrl: pointer to &struct v4l2_control
1428  *
1429  * If hdl == NULL then they will all return -EINVAL.
1430  */
1431 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1432 
1433 /**
1434  * v4l2_s_ctrl - Helper function to implement
1435  *	:ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1436  *
1437  * @fh: pointer to &struct v4l2_fh
1438  * @hdl: pointer to &struct v4l2_ctrl_handler
1439  *
1440  * @ctrl: pointer to &struct v4l2_control
1441  *
1442  * If hdl == NULL then they will all return -EINVAL.
1443  */
1444 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1445 		struct v4l2_control *ctrl);
1446 
1447 /**
1448  * v4l2_g_ext_ctrls - Helper function to implement
1449  *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1450  *
1451  * @hdl: pointer to &struct v4l2_ctrl_handler
1452  * @vdev: pointer to &struct video_device
1453  * @mdev: pointer to &struct media_device
1454  * @c: pointer to &struct v4l2_ext_controls
1455  *
1456  * If hdl == NULL then they will all return -EINVAL.
1457  */
1458 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1459 		     struct media_device *mdev, struct v4l2_ext_controls *c);
1460 
1461 /**
1462  * v4l2_try_ext_ctrls - Helper function to implement
1463  *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1464  *
1465  * @hdl: pointer to &struct v4l2_ctrl_handler
1466  * @vdev: pointer to &struct video_device
1467  * @mdev: pointer to &struct media_device
1468  * @c: pointer to &struct v4l2_ext_controls
1469  *
1470  * If hdl == NULL then they will all return -EINVAL.
1471  */
1472 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1473 		       struct video_device *vdev,
1474 		       struct media_device *mdev,
1475 		       struct v4l2_ext_controls *c);
1476 
1477 /**
1478  * v4l2_s_ext_ctrls - Helper function to implement
1479  *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1480  *
1481  * @fh: pointer to &struct v4l2_fh
1482  * @hdl: pointer to &struct v4l2_ctrl_handler
1483  * @vdev: pointer to &struct video_device
1484  * @mdev: pointer to &struct media_device
1485  * @c: pointer to &struct v4l2_ext_controls
1486  *
1487  * If hdl == NULL then they will all return -EINVAL.
1488  */
1489 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1490 		     struct video_device *vdev,
1491 		     struct media_device *mdev,
1492 		     struct v4l2_ext_controls *c);
1493 
1494 /**
1495  * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1496  *	as a &struct v4l2_subdev_core_ops subscribe_event function
1497  *	that just subscribes control events.
1498  *
1499  * @sd: pointer to &struct v4l2_subdev
1500  * @fh: pointer to &struct v4l2_fh
1501  * @sub: pointer to &struct v4l2_event_subscription
1502  */
1503 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1504 				     struct v4l2_event_subscription *sub);
1505 
1506 /**
1507  * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1508  *	 handler.
1509  *
1510  * @sd: pointer to &struct v4l2_subdev
1511  */
1512 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1513 
1514 /**
1515  * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1516  *				       properties
1517  *
1518  * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1519  * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1520  * @p: pointer to &struct v4l2_fwnode_device_properties
1521  *
1522  * This function registers controls associated to device properties, using the
1523  * property values contained in @p parameter, if the property has been set to
1524  * a value.
1525  *
1526  * Currently the following v4l2 controls are parsed and registered:
1527  * - V4L2_CID_CAMERA_ORIENTATION
1528  * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1529  *
1530  * Controls already registered by the caller with the @hdl control handler are
1531  * not overwritten. Callers should register the controls they want to handle
1532  * themselves before calling this function.
1533  *
1534  * Return: 0 on success, a negative error code on failure.
1535  */
1536 int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1537 				    const struct v4l2_ctrl_ops *ctrl_ops,
1538 				    const struct v4l2_fwnode_device_properties *p);
1539 
1540 /**
1541  * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1542  *
1543  * @ctrl: The v4l2_ctrl pointer.
1544  * @ptr1: A v4l2 control value.
1545  * @ptr2: A v4l2 control value.
1546  *
1547  * Return: true if values are equal, otherwise false.
1548  */
1549 bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl,
1550 			     union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1551 
1552 /**
1553  * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1554  *
1555  * @ctrl: The v4l2_ctrl pointer.
1556  * @from_idx: Starting element index.
1557  * @ptr: The v4l2 control value.
1558  *
1559  * Return: void
1560  */
1561 void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1562 			    union v4l2_ctrl_ptr ptr);
1563 
1564 /**
1565  * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1566  *
1567  * @ctrl: The v4l2_ctrl pointer.
1568  *
1569  * Return: void
1570  */
1571 void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1572 
1573 /**
1574  * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1575  *
1576  * @ctrl: The v4l2_ctrl pointer.
1577  * @ptr: The v4l2 control value.
1578  *
1579  * Return: 0 on success, a negative error code on failure.
1580  */
1581 int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1582 
1583 #endif
1584