xref: /openbmc/linux/include/media/v4l2-ctrls.h (revision 83b975b5)
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 both values are equal.
125  * @init: initialize the value.
126  * @log: log the value.
127  * @validate: validate the value. Return 0 on success and a negative value
128  *	otherwise.
129  */
130 struct v4l2_ctrl_type_ops {
131 	bool (*equal)(const struct v4l2_ctrl *ctrl, u32 elems,
132 		      union v4l2_ctrl_ptr ptr1,
133 		      union v4l2_ctrl_ptr ptr2);
134 	void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx, u32 tot_elems,
135 		     union v4l2_ctrl_ptr ptr);
136 	void (*log)(const struct v4l2_ctrl *ctrl);
137 	int (*validate)(const struct v4l2_ctrl *ctrl, u32 elems,
138 			union v4l2_ctrl_ptr ptr);
139 };
140 
141 /**
142  * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
143  *	that should be called when a control value has changed.
144  *
145  * @ctrl: pointer to struct &v4l2_ctrl
146  * @priv: control private data
147  *
148  * This typedef definition is used as an argument to v4l2_ctrl_notify()
149  * and as an argument at struct &v4l2_ctrl_handler.
150  */
151 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
152 
153 /**
154  * struct v4l2_ctrl - The control structure.
155  *
156  * @node:	The list node.
157  * @ev_subs:	The list of control event subscriptions.
158  * @handler:	The handler that owns the control.
159  * @cluster:	Point to start of cluster array.
160  * @ncontrols:	Number of controls in cluster array.
161  * @done:	Internal flag: set for each processed control.
162  * @is_new:	Set when the user specified a new value for this control. It
163  *		is also set when called from v4l2_ctrl_handler_setup(). Drivers
164  *		should never set this flag.
165  * @has_changed: Set when the current value differs from the new value. Drivers
166  *		should never use this flag.
167  * @is_private: If set, then this control is private to its handler and it
168  *		will not be added to any other handlers. Drivers can set
169  *		this flag.
170  * @is_auto:   If set, then this control selects whether the other cluster
171  *		members are in 'automatic' mode or 'manual' mode. This is
172  *		used for autogain/gain type clusters. Drivers should never
173  *		set this flag directly.
174  * @is_int:    If set, then this control has a simple integer value (i.e. it
175  *		uses ctrl->val).
176  * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
177  * @is_ptr:	If set, then this control is an array and/or has type >=
178  *		%V4L2_CTRL_COMPOUND_TYPES
179  *		and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
180  *		v4l2_ext_control uses field p to point to the data.
181  * @is_array: If set, then this control contains an N-dimensional array.
182  * @is_dyn_array: If set, then this control contains a dynamically sized 1-dimensional array.
183  *		If this is set, then @is_array is also set.
184  * @has_volatiles: If set, then one or more members of the cluster are volatile.
185  *		Drivers should never touch this flag.
186  * @call_notify: If set, then call the handler's notify function whenever the
187  *		control's value changes.
188  * @manual_mode_value: If the is_auto flag is set, then this is the value
189  *		of the auto control that determines if that control is in
190  *		manual mode. So if the value of the auto control equals this
191  *		value, then the whole cluster is in manual mode. Drivers should
192  *		never set this flag directly.
193  * @ops:	The control ops.
194  * @type_ops:	The control type ops.
195  * @id:	The control ID.
196  * @name:	The control name.
197  * @type:	The control type.
198  * @minimum:	The control's minimum value.
199  * @maximum:	The control's maximum value.
200  * @default_value: The control's default value.
201  * @step:	The control's step value for non-menu controls.
202  * @elems:	The number of elements in the N-dimensional array.
203  * @elem_size:	The size in bytes of the control.
204  * @new_elems:	The number of elements in p_new. This is the same as @elems,
205  *		except for dynamic arrays. In that case it is in the range of
206  *		1 to @p_array_alloc_elems.
207  * @dims:	The size of each dimension.
208  * @nr_of_dims:The number of dimensions in @dims.
209  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
210  *		easy to skip menu items that are not valid. If bit X is set,
211  *		then menu item X is skipped. Of course, this only works for
212  *		menus with <= 32 menu items. There are no menus that come
213  *		close to that number, so this is OK. Should we ever need more,
214  *		then this will have to be extended to a u64 or a bit array.
215  * @qmenu:	A const char * array for all menu items. Array entries that are
216  *		empty strings ("") correspond to non-existing menu items (this
217  *		is in addition to the menu_skip_mask above). The last entry
218  *		must be NULL.
219  *		Used only if the @type is %V4L2_CTRL_TYPE_MENU.
220  * @qmenu_int:	A 64-bit integer array for with integer menu items.
221  *		The size of array must be equal to the menu size, e. g.:
222  *		:math:`ceil(\frac{maximum - minimum}{step}) + 1`.
223  *		Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
224  * @flags:	The control's flags.
225  * @priv:	The control's private pointer. For use by the driver. It is
226  *		untouched by the control framework. Note that this pointer is
227  *		not freed when the control is deleted. Should this be needed
228  *		then a new internal bitfield can be added to tell the framework
229  *		to free this pointer.
230  * @p_array:	Pointer to the allocated array. Only valid if @is_array is true.
231  * @p_array_alloc_elems: The number of elements in the allocated
232  *		array for both the cur and new values. So @p_array is actually
233  *		sized for 2 * @p_array_alloc_elems * @elem_size. Only valid if
234  *		@is_array is true.
235  * @cur:	Structure to store the current value.
236  * @cur.val:	The control's current value, if the @type is represented via
237  *		a u32 integer (see &enum v4l2_ctrl_type).
238  * @val:	The control's new s32 value.
239  * @p_def:	The control's default value represented via a union which
240  *		provides a standard way of accessing control types
241  *		through a pointer (for compound controls only).
242  * @p_cur:	The control's current value represented via a union which
243  *		provides a standard way of accessing control types
244  *		through a pointer.
245  * @p_new:	The control's new value represented via a union which provides
246  *		a standard way of accessing control types
247  *		through a pointer.
248  */
249 struct v4l2_ctrl {
250 	/* Administrative fields */
251 	struct list_head node;
252 	struct list_head ev_subs;
253 	struct v4l2_ctrl_handler *handler;
254 	struct v4l2_ctrl **cluster;
255 	unsigned int ncontrols;
256 
257 	unsigned int done:1;
258 
259 	unsigned int is_new:1;
260 	unsigned int has_changed:1;
261 	unsigned int is_private:1;
262 	unsigned int is_auto:1;
263 	unsigned int is_int:1;
264 	unsigned int is_string:1;
265 	unsigned int is_ptr:1;
266 	unsigned int is_array:1;
267 	unsigned int is_dyn_array:1;
268 	unsigned int has_volatiles:1;
269 	unsigned int call_notify:1;
270 	unsigned int manual_mode_value:8;
271 
272 	const struct v4l2_ctrl_ops *ops;
273 	const struct v4l2_ctrl_type_ops *type_ops;
274 	u32 id;
275 	const char *name;
276 	enum v4l2_ctrl_type type;
277 	s64 minimum, maximum, default_value;
278 	u32 elems;
279 	u32 elem_size;
280 	u32 new_elems;
281 	u32 dims[V4L2_CTRL_MAX_DIMS];
282 	u32 nr_of_dims;
283 	union {
284 		u64 step;
285 		u64 menu_skip_mask;
286 	};
287 	union {
288 		const char * const *qmenu;
289 		const s64 *qmenu_int;
290 	};
291 	unsigned long flags;
292 	void *priv;
293 	void *p_array;
294 	u32 p_array_alloc_elems;
295 	s32 val;
296 	struct {
297 		s32 val;
298 	} cur;
299 
300 	union v4l2_ctrl_ptr p_def;
301 	union v4l2_ctrl_ptr p_new;
302 	union v4l2_ctrl_ptr p_cur;
303 };
304 
305 /**
306  * struct v4l2_ctrl_ref - The control reference.
307  *
308  * @node:	List node for the sorted list.
309  * @next:	Single-link list node for the hash.
310  * @ctrl:	The actual control information.
311  * @helper:	Pointer to helper struct. Used internally in
312  *		``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
313  * @from_other_dev: If true, then @ctrl was defined in another
314  *		device than the &struct v4l2_ctrl_handler.
315  * @req_done:	Internal flag: if the control handler containing this control
316  *		reference is bound to a media request, then this is set when
317  *		the control has been applied. This prevents applying controls
318  *		from a cluster with multiple controls twice (when the first
319  *		control of a cluster is applied, they all are).
320  * @p_req_valid: If set, then p_req contains the control value for the request.
321  * @p_req_array_enomem: If set, then p_req is invalid since allocating space for
322  *		an array failed. Attempting to read this value shall
323  *		result in ENOMEM. Only valid if ctrl->is_array is true.
324  * @p_req_array_alloc_elems: The number of elements allocated for the
325  *		array. Only valid if @p_req_valid and ctrl->is_array are
326  *		true.
327  * @p_req_elems: The number of elements in @p_req. This is the same as
328  *		ctrl->elems, except for dynamic arrays. In that case it is in
329  *		the range of 1 to @p_req_array_alloc_elems. Only valid if
330  *		@p_req_valid is true.
331  * @p_req:	If the control handler containing this control reference
332  *		is bound to a media request, then this points to the
333  *		value of the control that must be applied when the request
334  *		is executed, or to the value of the control at the time
335  *		that the request was completed. If @p_req_valid is false,
336  *		then this control was never set for this request and the
337  *		control will not be updated when this request is applied.
338  *
339  * Each control handler has a list of these refs. The list_head is used to
340  * keep a sorted-by-control-ID list of all controls, while the next pointer
341  * is used to link the control in the hash's bucket.
342  */
343 struct v4l2_ctrl_ref {
344 	struct list_head node;
345 	struct v4l2_ctrl_ref *next;
346 	struct v4l2_ctrl *ctrl;
347 	struct v4l2_ctrl_helper *helper;
348 	bool from_other_dev;
349 	bool req_done;
350 	bool p_req_valid;
351 	bool p_req_array_enomem;
352 	u32 p_req_array_alloc_elems;
353 	u32 p_req_elems;
354 	union v4l2_ctrl_ptr p_req;
355 };
356 
357 /**
358  * struct v4l2_ctrl_handler - The control handler keeps track of all the
359  *	controls: both the controls owned by the handler and those inherited
360  *	from other handlers.
361  *
362  * @_lock:	Default for "lock".
363  * @lock:	Lock to control access to this handler and its controls.
364  *		May be replaced by the user right after init.
365  * @ctrls:	The list of controls owned by this handler.
366  * @ctrl_refs:	The list of control references.
367  * @cached:	The last found control reference. It is common that the same
368  *		control is needed multiple times, so this is a simple
369  *		optimization.
370  * @buckets:	Buckets for the hashing. Allows for quick control lookup.
371  * @notify:	A notify callback that is called whenever the control changes
372  *		value.
373  *		Note that the handler's lock is held when the notify function
374  *		is called!
375  * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
376  * @nr_of_buckets: Total number of buckets in the array.
377  * @error:	The error code of the first failed control addition.
378  * @request_is_queued: True if the request was queued.
379  * @requests:	List to keep track of open control handler request objects.
380  *		For the parent control handler (@req_obj.ops == NULL) this
381  *		is the list header. When the parent control handler is
382  *		removed, it has to unbind and put all these requests since
383  *		they refer to the parent.
384  * @requests_queued: List of the queued requests. This determines the order
385  *		in which these controls are applied. Once the request is
386  *		completed it is removed from this list.
387  * @req_obj:	The &struct media_request_object, used to link into a
388  *		&struct media_request. This request object has a refcount.
389  */
390 struct v4l2_ctrl_handler {
391 	struct mutex _lock;
392 	struct mutex *lock;
393 	struct list_head ctrls;
394 	struct list_head ctrl_refs;
395 	struct v4l2_ctrl_ref *cached;
396 	struct v4l2_ctrl_ref **buckets;
397 	v4l2_ctrl_notify_fnc notify;
398 	void *notify_priv;
399 	u16 nr_of_buckets;
400 	int error;
401 	bool request_is_queued;
402 	struct list_head requests;
403 	struct list_head requests_queued;
404 	struct media_request_object req_obj;
405 };
406 
407 /**
408  * struct v4l2_ctrl_config - Control configuration structure.
409  *
410  * @ops:	The control ops.
411  * @type_ops:	The control type ops. Only needed for compound controls.
412  * @id:	The control ID.
413  * @name:	The control name.
414  * @type:	The control type.
415  * @min:	The control's minimum value.
416  * @max:	The control's maximum value.
417  * @step:	The control's step value for non-menu controls.
418  * @def:	The control's default value.
419  * @p_def:	The control's default value for compound controls.
420  * @dims:	The size of each dimension.
421  * @elem_size:	The size in bytes of the control.
422  * @flags:	The control's flags.
423  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
424  *		easy to skip menu items that are not valid. If bit X is set,
425  *		then menu item X is skipped. Of course, this only works for
426  *		menus with <= 64 menu items. There are no menus that come
427  *		close to that number, so this is OK. Should we ever need more,
428  *		then this will have to be extended to a bit array.
429  * @qmenu:	A const char * array for all menu items. Array entries that are
430  *		empty strings ("") correspond to non-existing menu items (this
431  *		is in addition to the menu_skip_mask above). The last entry
432  *		must be NULL.
433  * @qmenu_int:	A const s64 integer array for all menu items of the type
434  *		V4L2_CTRL_TYPE_INTEGER_MENU.
435  * @is_private: If set, then this control is private to its handler and it
436  *		will not be added to any other handlers.
437  */
438 struct v4l2_ctrl_config {
439 	const struct v4l2_ctrl_ops *ops;
440 	const struct v4l2_ctrl_type_ops *type_ops;
441 	u32 id;
442 	const char *name;
443 	enum v4l2_ctrl_type type;
444 	s64 min;
445 	s64 max;
446 	u64 step;
447 	s64 def;
448 	union v4l2_ctrl_ptr p_def;
449 	u32 dims[V4L2_CTRL_MAX_DIMS];
450 	u32 elem_size;
451 	u32 flags;
452 	u64 menu_skip_mask;
453 	const char * const *qmenu;
454 	const s64 *qmenu_int;
455 	unsigned int is_private:1;
456 };
457 
458 /**
459  * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
460  *
461  * @id: ID of the control
462  * @name: pointer to be filled with a string with the name of the control
463  * @type: pointer for storing the type of the control
464  * @min: pointer for storing the minimum value for the control
465  * @max: pointer for storing the maximum value for the control
466  * @step: pointer for storing the control step
467  * @def: pointer for storing the default value for the control
468  * @flags: pointer for storing the flags to be used on the control
469  *
470  * This works for all standard V4L2 controls.
471  * For non-standard controls it will only fill in the given arguments
472  * and @name content will be set to %NULL.
473  *
474  * This function will overwrite the contents of @name, @type and @flags.
475  * The contents of @min, @max, @step and @def may be modified depending on
476  * the type.
477  *
478  * .. note::
479  *
480  *    Do not use in drivers! It is used internally for backwards compatibility
481  *    control handling only. Once all drivers are converted to use the new
482  *    control framework this function will no longer be exported.
483  */
484 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
485 		    s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
486 
487 
488 /**
489  * v4l2_ctrl_handler_init_class() - Initialize the control handler.
490  * @hdl:	The control handler.
491  * @nr_of_controls_hint: A hint of how many controls this handler is
492  *		expected to refer to. This is the total number, so including
493  *		any inherited controls. It doesn't have to be precise, but if
494  *		it is way off, then you either waste memory (too many buckets
495  *		are allocated) or the control lookup becomes slower (not enough
496  *		buckets are allocated, so there are more slow list lookups).
497  *		It will always work, though.
498  * @key:	Used by the lock validator if CONFIG_LOCKDEP is set.
499  * @name:	Used by the lock validator if CONFIG_LOCKDEP is set.
500  *
501  * .. attention::
502  *
503  *    Never use this call directly, always use the v4l2_ctrl_handler_init()
504  *    macro that hides the @key and @name arguments.
505  *
506  * Return: returns an error if the buckets could not be allocated. This
507  * error will also be stored in @hdl->error.
508  */
509 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
510 				 unsigned int nr_of_controls_hint,
511 				 struct lock_class_key *key, const char *name);
512 
513 #ifdef CONFIG_LOCKDEP
514 
515 /**
516  * v4l2_ctrl_handler_init - helper function to create a static struct
517  *	 &lock_class_key and calls v4l2_ctrl_handler_init_class()
518  *
519  * @hdl:	The control handler.
520  * @nr_of_controls_hint: A hint of how many controls this handler is
521  *		expected to refer to. This is the total number, so including
522  *		any inherited controls. It doesn't have to be precise, but if
523  *		it is way off, then you either waste memory (too many buckets
524  *		are allocated) or the control lookup becomes slower (not enough
525  *		buckets are allocated, so there are more slow list lookups).
526  *		It will always work, though.
527  *
528  * This helper function creates a static struct &lock_class_key and
529  * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
530  * validador.
531  *
532  * Use this helper function to initialize a control handler.
533  */
534 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
535 (									\
536 	({								\
537 		static struct lock_class_key _key;			\
538 		v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint,	\
539 					&_key,				\
540 					KBUILD_BASENAME ":"		\
541 					__stringify(__LINE__) ":"	\
542 					"(" #hdl ")->_lock");		\
543 	})								\
544 )
545 #else
546 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
547 	v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
548 #endif
549 
550 /**
551  * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
552  * the control list.
553  * @hdl:	The control handler.
554  *
555  * Does nothing if @hdl == NULL.
556  */
557 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
558 
559 /**
560  * v4l2_ctrl_lock() - Helper function to lock the handler
561  * associated with the control.
562  * @ctrl:	The control to lock.
563  */
564 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
565 {
566 	mutex_lock(ctrl->handler->lock);
567 }
568 
569 /**
570  * v4l2_ctrl_unlock() - Helper function to unlock the handler
571  * associated with the control.
572  * @ctrl:	The control to unlock.
573  */
574 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
575 {
576 	mutex_unlock(ctrl->handler->lock);
577 }
578 
579 /**
580  * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
581  * to the handler to initialize the hardware to the current control values. The
582  * caller is responsible for acquiring the control handler mutex on behalf of
583  * __v4l2_ctrl_handler_setup().
584  * @hdl:	The control handler.
585  *
586  * Button controls will be skipped, as are read-only controls.
587  *
588  * If @hdl == NULL, then this just returns 0.
589  */
590 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
591 
592 /**
593  * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
594  * to the handler to initialize the hardware to the current control values.
595  * @hdl:	The control handler.
596  *
597  * Button controls will be skipped, as are read-only controls.
598  *
599  * If @hdl == NULL, then this just returns 0.
600  */
601 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
602 
603 /**
604  * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
605  * @hdl:	The control handler.
606  * @prefix:	The prefix to use when logging the control values. If the
607  *		prefix does not end with a space, then ": " will be added
608  *		after the prefix. If @prefix == NULL, then no prefix will be
609  *		used.
610  *
611  * For use with VIDIOC_LOG_STATUS.
612  *
613  * Does nothing if @hdl == NULL.
614  */
615 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
616 				  const char *prefix);
617 
618 /**
619  * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
620  *	control.
621  *
622  * @hdl:	The control handler.
623  * @cfg:	The control's configuration data.
624  * @priv:	The control's driver-specific private data.
625  *
626  * If the &v4l2_ctrl struct could not be allocated then NULL is returned
627  * and @hdl->error is set to the error code (if it wasn't set already).
628  */
629 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
630 				       const struct v4l2_ctrl_config *cfg,
631 				       void *priv);
632 
633 /**
634  * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
635  *	control.
636  *
637  * @hdl:	The control handler.
638  * @ops:	The control ops.
639  * @id:		The control ID.
640  * @min:	The control's minimum value.
641  * @max:	The control's maximum value.
642  * @step:	The control's step value
643  * @def:	The control's default value.
644  *
645  * If the &v4l2_ctrl struct could not be allocated, or the control
646  * ID is not known, then NULL is returned and @hdl->error is set to the
647  * appropriate error code (if it wasn't set already).
648  *
649  * If @id refers to a menu control, then this function will return NULL.
650  *
651  * Use v4l2_ctrl_new_std_menu() when adding menu controls.
652  */
653 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
654 				    const struct v4l2_ctrl_ops *ops,
655 				    u32 id, s64 min, s64 max, u64 step,
656 				    s64 def);
657 
658 /**
659  * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
660  *	menu control.
661  *
662  * @hdl:	The control handler.
663  * @ops:	The control ops.
664  * @id:		The control ID.
665  * @max:	The control's maximum value.
666  * @mask:	The control's skip mask for menu controls. This makes it
667  *		easy to skip menu items that are not valid. If bit X is set,
668  *		then menu item X is skipped. Of course, this only works for
669  *		menus with <= 64 menu items. There are no menus that come
670  *		close to that number, so this is OK. Should we ever need more,
671  *		then this will have to be extended to a bit array.
672  * @def:	The control's default value.
673  *
674  * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
675  * determines which menu items are to be skipped.
676  *
677  * If @id refers to a non-menu control, then this function will return NULL.
678  */
679 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
680 					 const struct v4l2_ctrl_ops *ops,
681 					 u32 id, u8 max, u64 mask, u8 def);
682 
683 /**
684  * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
685  *	with driver specific menu.
686  *
687  * @hdl:	The control handler.
688  * @ops:	The control ops.
689  * @id:	The control ID.
690  * @max:	The control's maximum value.
691  * @mask:	The control's skip mask for menu controls. This makes it
692  *		easy to skip menu items that are not valid. If bit X is set,
693  *		then menu item X is skipped. Of course, this only works for
694  *		menus with <= 64 menu items. There are no menus that come
695  *		close to that number, so this is OK. Should we ever need more,
696  *		then this will have to be extended to a bit array.
697  * @def:	The control's default value.
698  * @qmenu:	The new menu.
699  *
700  * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
701  * menu of this control.
702  *
703  */
704 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
705 					       const struct v4l2_ctrl_ops *ops,
706 					       u32 id, u8 max,
707 					       u64 mask, u8 def,
708 					       const char * const *qmenu);
709 
710 /**
711  * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
712  *      compound control.
713  *
714  * @hdl:       The control handler.
715  * @ops:       The control ops.
716  * @id:        The control ID.
717  * @p_def:     The control's default value.
718  *
719  * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
720  * to the @p_def field. Use v4l2_ctrl_ptr_create() to create @p_def from a
721  * pointer. Use v4l2_ctrl_ptr_create(NULL) if the default value of the
722  * compound control should be all zeroes.
723  *
724  */
725 struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
726 					     const struct v4l2_ctrl_ops *ops,
727 					     u32 id,
728 					     const union v4l2_ctrl_ptr p_def);
729 
730 /**
731  * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
732  *
733  * @hdl:	The control handler.
734  * @ops:	The control ops.
735  * @id:	The control ID.
736  * @max:	The control's maximum value.
737  * @def:	The control's default value.
738  * @qmenu_int:	The control's menu entries.
739  *
740  * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
741  * takes as an argument an array of integers determining the menu items.
742  *
743  * If @id refers to a non-integer-menu control, then this function will
744  * return %NULL.
745  */
746 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
747 					 const struct v4l2_ctrl_ops *ops,
748 					 u32 id, u8 max, u8 def,
749 					 const s64 *qmenu_int);
750 
751 /**
752  * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
753  *	used when adding a control handler.
754  *
755  * @ctrl: pointer to struct &v4l2_ctrl.
756  */
757 
758 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
759 
760 /**
761  * v4l2_ctrl_add_handler() - Add all controls from handler @add to
762  *	handler @hdl.
763  *
764  * @hdl:	The control handler.
765  * @add:	The control handler whose controls you want to add to
766  *		the @hdl control handler.
767  * @filter:	This function will filter which controls should be added.
768  * @from_other_dev: If true, then the controls in @add were defined in another
769  *		device than @hdl.
770  *
771  * Does nothing if either of the two handlers is a NULL pointer.
772  * If @filter is NULL, then all controls are added. Otherwise only those
773  * controls for which @filter returns true will be added.
774  * In case of an error @hdl->error will be set to the error code (if it
775  * wasn't set already).
776  */
777 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
778 			  struct v4l2_ctrl_handler *add,
779 			  v4l2_ctrl_filter filter,
780 			  bool from_other_dev);
781 
782 /**
783  * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
784  *
785  * @ctrl:	The control that is filtered.
786  *
787  * This will return true for any controls that are valid for radio device
788  * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
789  * transmitter class controls.
790  *
791  * This function is to be used with v4l2_ctrl_add_handler().
792  */
793 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
794 
795 /**
796  * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
797  *	to that cluster.
798  *
799  * @ncontrols:	The number of controls in this cluster.
800  * @controls:	The cluster control array of size @ncontrols.
801  */
802 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
803 
804 
805 /**
806  * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
807  *	to that cluster and set it up for autofoo/foo-type handling.
808  *
809  * @ncontrols:	The number of controls in this cluster.
810  * @controls:	The cluster control array of size @ncontrols. The first control
811  *		must be the 'auto' control (e.g. autogain, autoexposure, etc.)
812  * @manual_val: The value for the first control in the cluster that equals the
813  *		manual setting.
814  * @set_volatile: If true, then all controls except the first auto control will
815  *		be volatile.
816  *
817  * Use for control groups where one control selects some automatic feature and
818  * the other controls are only active whenever the automatic feature is turned
819  * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
820  * red and blue balance, etc.
821  *
822  * The behavior of such controls is as follows:
823  *
824  * When the autofoo control is set to automatic, then any manual controls
825  * are set to inactive and any reads will call g_volatile_ctrl (if the control
826  * was marked volatile).
827  *
828  * When the autofoo control is set to manual, then any manual controls will
829  * be marked active, and any reads will just return the current value without
830  * going through g_volatile_ctrl.
831  *
832  * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
833  * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
834  * if autofoo is in auto mode.
835  */
836 void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
837 			    struct v4l2_ctrl **controls,
838 			    u8 manual_val, bool set_volatile);
839 
840 
841 /**
842  * v4l2_ctrl_find() - Find a control with the given ID.
843  *
844  * @hdl:	The control handler.
845  * @id:	The control ID to find.
846  *
847  * If @hdl == NULL this will return NULL as well. Will lock the handler so
848  * do not use from inside &v4l2_ctrl_ops.
849  */
850 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
851 
852 /**
853  * v4l2_ctrl_activate() - Make the control active or inactive.
854  * @ctrl:	The control to (de)activate.
855  * @active:	True if the control should become active.
856  *
857  * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
858  * Does nothing if @ctrl == NULL.
859  * This will usually be called from within the s_ctrl op.
860  * The V4L2_EVENT_CTRL event will be generated afterwards.
861  *
862  * This function assumes that the control handler is locked.
863  */
864 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
865 
866 /**
867  * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
868  *
869  * @ctrl:	The control to (de)activate.
870  * @grabbed:	True if the control should become grabbed.
871  *
872  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
873  * Does nothing if @ctrl == NULL.
874  * The V4L2_EVENT_CTRL event will be generated afterwards.
875  * This will usually be called when starting or stopping streaming in the
876  * driver.
877  *
878  * This function assumes that the control handler is locked by the caller.
879  */
880 void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
881 
882 /**
883  * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
884  *
885  * @ctrl:	The control to (de)activate.
886  * @grabbed:	True if the control should become grabbed.
887  *
888  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
889  * Does nothing if @ctrl == NULL.
890  * The V4L2_EVENT_CTRL event will be generated afterwards.
891  * This will usually be called when starting or stopping streaming in the
892  * driver.
893  *
894  * This function assumes that the control handler is not locked and will
895  * take the lock itself.
896  */
897 static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
898 {
899 	if (!ctrl)
900 		return;
901 
902 	v4l2_ctrl_lock(ctrl);
903 	__v4l2_ctrl_grab(ctrl, grabbed);
904 	v4l2_ctrl_unlock(ctrl);
905 }
906 
907 /**
908  *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
909  *
910  * @ctrl:	The control to update.
911  * @min:	The control's minimum value.
912  * @max:	The control's maximum value.
913  * @step:	The control's step value
914  * @def:	The control's default value.
915  *
916  * Update the range of a control on the fly. This works for control types
917  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
918  * @step value is interpreted as a menu_skip_mask.
919  *
920  * An error is returned if one of the range arguments is invalid for this
921  * control type.
922  *
923  * The caller is responsible for acquiring the control handler mutex on behalf
924  * of __v4l2_ctrl_modify_range().
925  */
926 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
927 			     s64 min, s64 max, u64 step, s64 def);
928 
929 /**
930  * v4l2_ctrl_modify_range() - Update the range of a control.
931  *
932  * @ctrl:	The control to update.
933  * @min:	The control's minimum value.
934  * @max:	The control's maximum value.
935  * @step:	The control's step value
936  * @def:	The control's default value.
937  *
938  * Update the range of a control on the fly. This works for control types
939  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
940  * @step value is interpreted as a menu_skip_mask.
941  *
942  * An error is returned if one of the range arguments is invalid for this
943  * control type.
944  *
945  * This function assumes that the control handler is not locked and will
946  * take the lock itself.
947  */
948 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
949 					 s64 min, s64 max, u64 step, s64 def)
950 {
951 	int rval;
952 
953 	v4l2_ctrl_lock(ctrl);
954 	rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
955 	v4l2_ctrl_unlock(ctrl);
956 
957 	return rval;
958 }
959 
960 /**
961  *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
962  *
963  * @ctrl:	The control to update.
964  * @dims:	The control's new dimensions.
965  *
966  * Update the dimensions of an array control on the fly. The elements of the
967  * array are reset to their default value, even if the dimensions are
968  * unchanged.
969  *
970  * An error is returned if @dims is invalid for this control.
971  *
972  * The caller is responsible for acquiring the control handler mutex on behalf
973  * of __v4l2_ctrl_modify_dimensions().
974  *
975  * Note: calling this function when the same control is used in pending requests
976  * is untested. It should work (a request with the wrong size of the control
977  * will drop that control silently), but it will be very confusing.
978  */
979 int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
980 				  u32 dims[V4L2_CTRL_MAX_DIMS]);
981 
982 /**
983  * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
984  *
985  * @ctrl:	The control to update.
986  * @dims:	The control's new dimensions.
987  *
988  * Update the dimensions of an array control on the fly. The elements of the
989  * array are reset to their default value, even if the dimensions are
990  * unchanged.
991  *
992  * An error is returned if @dims is invalid for this control type.
993  *
994  * This function assumes that the control handler is not locked and will
995  * take the lock itself.
996  *
997  * Note: calling this function when the same control is used in pending requests
998  * is untested. It should work (a request with the wrong size of the control
999  * will drop that control silently), but it will be very confusing.
1000  */
1001 static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1002 					      u32 dims[V4L2_CTRL_MAX_DIMS])
1003 {
1004 	int rval;
1005 
1006 	v4l2_ctrl_lock(ctrl);
1007 	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1008 	v4l2_ctrl_unlock(ctrl);
1009 
1010 	return rval;
1011 }
1012 
1013 /**
1014  * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1015  *
1016  * @ctrl:	The control.
1017  * @notify:	The callback function.
1018  * @priv:	The callback private handle, passed as argument to the callback.
1019  *
1020  * This function sets a callback function for the control. If @ctrl is NULL,
1021  * then it will do nothing. If @notify is NULL, then the notify callback will
1022  * be removed.
1023  *
1024  * There can be only one notify. If another already exists, then a WARN_ON
1025  * will be issued and the function will do nothing.
1026  */
1027 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1028 		      void *priv);
1029 
1030 /**
1031  * v4l2_ctrl_get_name() - Get the name of the control
1032  *
1033  * @id:		The control ID.
1034  *
1035  * This function returns the name of the given control ID or NULL if it isn't
1036  * a known control.
1037  */
1038 const char *v4l2_ctrl_get_name(u32 id);
1039 
1040 /**
1041  * v4l2_ctrl_get_menu() - Get the menu string array of the control
1042  *
1043  * @id:		The control ID.
1044  *
1045  * This function returns the NULL-terminated menu string array name of the
1046  * given control ID or NULL if it isn't a known menu control.
1047  */
1048 const char * const *v4l2_ctrl_get_menu(u32 id);
1049 
1050 /**
1051  * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1052  *
1053  * @id:		The control ID.
1054  * @len:	The size of the integer array.
1055  *
1056  * This function returns the integer array of the given control ID or NULL if it
1057  * if it isn't a known integer menu control.
1058  */
1059 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1060 
1061 /**
1062  * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1063  *	within a driver.
1064  *
1065  * @ctrl:	The control.
1066  *
1067  * This returns the control's value safely by going through the control
1068  * framework. This function will lock the control's handler, so it cannot be
1069  * used from within the &v4l2_ctrl_ops functions.
1070  *
1071  * This function is for integer type controls only.
1072  */
1073 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1074 
1075 /**
1076  * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1077  *
1078  * @ctrl:	The control.
1079  * @val:	The new value.
1080  *
1081  * This sets the control's new value safely by going through the control
1082  * framework. This function assumes the control's handler is already locked,
1083  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1084  *
1085  * This function is for integer type controls only.
1086  */
1087 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1088 
1089 /**
1090  * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1091  *	within a driver.
1092  * @ctrl:	The control.
1093  * @val:	The new value.
1094  *
1095  * This sets the control's new value safely by going through the control
1096  * framework. This function will lock the control's handler, so it cannot be
1097  * used from within the &v4l2_ctrl_ops functions.
1098  *
1099  * This function is for integer type controls only.
1100  */
1101 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1102 {
1103 	int rval;
1104 
1105 	v4l2_ctrl_lock(ctrl);
1106 	rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1107 	v4l2_ctrl_unlock(ctrl);
1108 
1109 	return rval;
1110 }
1111 
1112 /**
1113  * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1114  *	from within a driver.
1115  *
1116  * @ctrl:	The control.
1117  *
1118  * This returns the control's value safely by going through the control
1119  * framework. This function will lock the control's handler, so it cannot be
1120  * used from within the &v4l2_ctrl_ops functions.
1121  *
1122  * This function is for 64-bit integer type controls only.
1123  */
1124 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1125 
1126 /**
1127  * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1128  *
1129  * @ctrl:	The control.
1130  * @val:	The new value.
1131  *
1132  * This sets the control's new value safely by going through the control
1133  * framework. This function assumes the control's handler is already locked,
1134  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1135  *
1136  * This function is for 64-bit integer type controls only.
1137  */
1138 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1139 
1140 /**
1141  * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1142  *	from within a driver.
1143  *
1144  * @ctrl:	The control.
1145  * @val:	The new value.
1146  *
1147  * This sets the control's new value safely by going through the control
1148  * framework. This function will lock the control's handler, so it cannot be
1149  * used from within the &v4l2_ctrl_ops functions.
1150  *
1151  * This function is for 64-bit integer type controls only.
1152  */
1153 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1154 {
1155 	int rval;
1156 
1157 	v4l2_ctrl_lock(ctrl);
1158 	rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1159 	v4l2_ctrl_unlock(ctrl);
1160 
1161 	return rval;
1162 }
1163 
1164 /**
1165  * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1166  *
1167  * @ctrl:	The control.
1168  * @s:		The new string.
1169  *
1170  * This sets the control's new string safely by going through the control
1171  * framework. This function assumes the control's handler is already locked,
1172  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1173  *
1174  * This function is for string type controls only.
1175  */
1176 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1177 
1178 /**
1179  * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1180  *	 from within a driver.
1181  *
1182  * @ctrl:	The control.
1183  * @s:		The new string.
1184  *
1185  * This sets the control's new string safely by going through the control
1186  * framework. This function will lock the control's handler, so it cannot be
1187  * used from within the &v4l2_ctrl_ops functions.
1188  *
1189  * This function is for string type controls only.
1190  */
1191 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1192 {
1193 	int rval;
1194 
1195 	v4l2_ctrl_lock(ctrl);
1196 	rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1197 	v4l2_ctrl_unlock(ctrl);
1198 
1199 	return rval;
1200 }
1201 
1202 /**
1203  * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1204  *
1205  * @ctrl: The control.
1206  * @type: The type of the data.
1207  * @p:    The new compound payload.
1208  *
1209  * This sets the control's new compound payload safely by going through the
1210  * control framework. This function assumes the control's handler is already
1211  * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1212  *
1213  * This function is for compound type controls only.
1214  */
1215 int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1216 				enum v4l2_ctrl_type type, const void *p);
1217 
1218 /**
1219  * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1220  *	from within a driver.
1221  *
1222  * @ctrl: The control.
1223  * @type: The type of the data.
1224  * @p:    The new compound payload.
1225  *
1226  * This sets the control's new compound payload safely by going through the
1227  * control framework. This function will lock the control's handler, so it
1228  * cannot be used from within the &v4l2_ctrl_ops functions.
1229  *
1230  * This function is for compound type controls only.
1231  */
1232 static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1233 					    enum v4l2_ctrl_type type,
1234 					    const void *p)
1235 {
1236 	int rval;
1237 
1238 	v4l2_ctrl_lock(ctrl);
1239 	rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1240 	v4l2_ctrl_unlock(ctrl);
1241 
1242 	return rval;
1243 }
1244 
1245 /* Helper defines for area type controls */
1246 #define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1247 	__v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1248 #define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1249 	v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1250 
1251 /* Internal helper functions that deal with control events. */
1252 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1253 
1254 /**
1255  * v4l2_ctrl_replace - Function to be used as a callback to
1256  *	&struct v4l2_subscribed_event_ops replace\(\)
1257  *
1258  * @old: pointer to struct &v4l2_event with the reported
1259  *	 event;
1260  * @new: pointer to struct &v4l2_event with the modified
1261  *	 event;
1262  */
1263 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1264 
1265 /**
1266  * v4l2_ctrl_merge - Function to be used as a callback to
1267  *	&struct v4l2_subscribed_event_ops merge(\)
1268  *
1269  * @old: pointer to struct &v4l2_event with the reported
1270  *	 event;
1271  * @new: pointer to struct &v4l2_event with the merged
1272  *	 event;
1273  */
1274 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1275 
1276 /**
1277  * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1278  *
1279  * @file: pointer to struct file
1280  * @fh: unused. Kept just to be compatible to the arguments expected by
1281  *	&struct v4l2_ioctl_ops.vidioc_log_status.
1282  *
1283  * Can be used as a vidioc_log_status function that just dumps all controls
1284  * associated with the filehandle.
1285  */
1286 int v4l2_ctrl_log_status(struct file *file, void *fh);
1287 
1288 /**
1289  * v4l2_ctrl_subscribe_event - Subscribes to an event
1290  *
1291  *
1292  * @fh: pointer to struct v4l2_fh
1293  * @sub: pointer to &struct v4l2_event_subscription
1294  *
1295  * Can be used as a vidioc_subscribe_event function that just subscribes
1296  * control events.
1297  */
1298 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1299 				const struct v4l2_event_subscription *sub);
1300 
1301 /**
1302  * v4l2_ctrl_poll - function to be used as a callback to the poll()
1303  *	That just polls for control events.
1304  *
1305  * @file: pointer to struct file
1306  * @wait: pointer to struct poll_table_struct
1307  */
1308 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1309 
1310 /**
1311  * v4l2_ctrl_request_setup - helper function to apply control values in a request
1312  *
1313  * @req: The request
1314  * @parent: The parent control handler ('priv' in media_request_object_find())
1315  *
1316  * This is a helper function to call the control handler's s_ctrl callback with
1317  * the control values contained in the request. Do note that this approach of
1318  * applying control values in a request is only applicable to memory-to-memory
1319  * devices.
1320  */
1321 int v4l2_ctrl_request_setup(struct media_request *req,
1322 			     struct v4l2_ctrl_handler *parent);
1323 
1324 /**
1325  * v4l2_ctrl_request_complete - Complete a control handler request object
1326  *
1327  * @req: The request
1328  * @parent: The parent control handler ('priv' in media_request_object_find())
1329  *
1330  * This function is to be called on each control handler that may have had a
1331  * request object associated with it, i.e. control handlers of a driver that
1332  * supports requests.
1333  *
1334  * The function first obtains the values of any volatile controls in the control
1335  * handler and attach them to the request. Then, the function completes the
1336  * request object.
1337  */
1338 void v4l2_ctrl_request_complete(struct media_request *req,
1339 				struct v4l2_ctrl_handler *parent);
1340 
1341 /**
1342  * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1343  *
1344  * @req: The request
1345  * @parent: The parent control handler ('priv' in media_request_object_find())
1346  *
1347  * This function finds the control handler in the request. It may return
1348  * NULL if not found. When done, you must call v4l2_ctrl_request_put_hdl()
1349  * with the returned handler pointer.
1350  *
1351  * If the request is not in state VALIDATING or QUEUED, then this function
1352  * will always return NULL.
1353  *
1354  * Note that in state VALIDATING the req_queue_mutex is held, so
1355  * no objects can be added or deleted from the request.
1356  *
1357  * In state QUEUED it is the driver that will have to ensure this.
1358  */
1359 struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1360 					struct v4l2_ctrl_handler *parent);
1361 
1362 /**
1363  * v4l2_ctrl_request_hdl_put - Put the control handler
1364  *
1365  * @hdl: Put this control handler
1366  *
1367  * This function released the control handler previously obtained from'
1368  * v4l2_ctrl_request_hdl_find().
1369  */
1370 static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1371 {
1372 	if (hdl)
1373 		media_request_object_put(&hdl->req_obj);
1374 }
1375 
1376 /**
1377  * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1378  *
1379  * @hdl: The control handler from the request.
1380  * @id: The ID of the control to find.
1381  *
1382  * This function returns a pointer to the control if this control is
1383  * part of the request or NULL otherwise.
1384  */
1385 struct v4l2_ctrl *
1386 v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1387 
1388 /* Helpers for ioctl_ops */
1389 
1390 /**
1391  * v4l2_queryctrl - Helper function to implement
1392  *	:ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1393  *
1394  * @hdl: pointer to &struct v4l2_ctrl_handler
1395  * @qc: pointer to &struct v4l2_queryctrl
1396  *
1397  * If hdl == NULL then they will all return -EINVAL.
1398  */
1399 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1400 
1401 /**
1402  * v4l2_query_ext_ctrl - Helper function to implement
1403  *	 :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1404  *
1405  * @hdl: pointer to &struct v4l2_ctrl_handler
1406  * @qc: pointer to &struct v4l2_query_ext_ctrl
1407  *
1408  * If hdl == NULL then they will all return -EINVAL.
1409  */
1410 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1411 			struct v4l2_query_ext_ctrl *qc);
1412 
1413 /**
1414  * v4l2_querymenu - Helper function to implement
1415  *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1416  *
1417  * @hdl: pointer to &struct v4l2_ctrl_handler
1418  * @qm: pointer to &struct v4l2_querymenu
1419  *
1420  * If hdl == NULL then they will all return -EINVAL.
1421  */
1422 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1423 
1424 /**
1425  * v4l2_g_ctrl - Helper function to implement
1426  *	:ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1427  *
1428  * @hdl: pointer to &struct v4l2_ctrl_handler
1429  * @ctrl: pointer to &struct v4l2_control
1430  *
1431  * If hdl == NULL then they will all return -EINVAL.
1432  */
1433 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1434 
1435 /**
1436  * v4l2_s_ctrl - Helper function to implement
1437  *	:ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1438  *
1439  * @fh: pointer to &struct v4l2_fh
1440  * @hdl: pointer to &struct v4l2_ctrl_handler
1441  *
1442  * @ctrl: pointer to &struct v4l2_control
1443  *
1444  * If hdl == NULL then they will all return -EINVAL.
1445  */
1446 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1447 		struct v4l2_control *ctrl);
1448 
1449 /**
1450  * v4l2_g_ext_ctrls - Helper function to implement
1451  *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1452  *
1453  * @hdl: pointer to &struct v4l2_ctrl_handler
1454  * @vdev: pointer to &struct video_device
1455  * @mdev: pointer to &struct media_device
1456  * @c: pointer to &struct v4l2_ext_controls
1457  *
1458  * If hdl == NULL then they will all return -EINVAL.
1459  */
1460 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1461 		     struct media_device *mdev, struct v4l2_ext_controls *c);
1462 
1463 /**
1464  * v4l2_try_ext_ctrls - Helper function to implement
1465  *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1466  *
1467  * @hdl: pointer to &struct v4l2_ctrl_handler
1468  * @vdev: pointer to &struct video_device
1469  * @mdev: pointer to &struct media_device
1470  * @c: pointer to &struct v4l2_ext_controls
1471  *
1472  * If hdl == NULL then they will all return -EINVAL.
1473  */
1474 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1475 		       struct video_device *vdev,
1476 		       struct media_device *mdev,
1477 		       struct v4l2_ext_controls *c);
1478 
1479 /**
1480  * v4l2_s_ext_ctrls - Helper function to implement
1481  *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1482  *
1483  * @fh: pointer to &struct v4l2_fh
1484  * @hdl: pointer to &struct v4l2_ctrl_handler
1485  * @vdev: pointer to &struct video_device
1486  * @mdev: pointer to &struct media_device
1487  * @c: pointer to &struct v4l2_ext_controls
1488  *
1489  * If hdl == NULL then they will all return -EINVAL.
1490  */
1491 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1492 		     struct video_device *vdev,
1493 		     struct media_device *mdev,
1494 		     struct v4l2_ext_controls *c);
1495 
1496 /**
1497  * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1498  *	as a &struct v4l2_subdev_core_ops subscribe_event function
1499  *	that just subscribes control events.
1500  *
1501  * @sd: pointer to &struct v4l2_subdev
1502  * @fh: pointer to &struct v4l2_fh
1503  * @sub: pointer to &struct v4l2_event_subscription
1504  */
1505 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1506 				     struct v4l2_event_subscription *sub);
1507 
1508 /**
1509  * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1510  *	 handler.
1511  *
1512  * @sd: pointer to &struct v4l2_subdev
1513  */
1514 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1515 
1516 /**
1517  * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1518  *				       properties
1519  *
1520  * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1521  * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1522  * @p: pointer to &struct v4l2_fwnode_device_properties
1523  *
1524  * This function registers controls associated to device properties, using the
1525  * property values contained in @p parameter, if the property has been set to
1526  * a value.
1527  *
1528  * Currently the following v4l2 controls are parsed and registered:
1529  * - V4L2_CID_CAMERA_ORIENTATION
1530  * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1531  *
1532  * Controls already registered by the caller with the @hdl control handler are
1533  * not overwritten. Callers should register the controls they want to handle
1534  * themselves before calling this function.
1535  *
1536  * Return: 0 on success, a negative error code on failure.
1537  */
1538 int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1539 				    const struct v4l2_ctrl_ops *ctrl_ops,
1540 				    const struct v4l2_fwnode_device_properties *p);
1541 
1542 /**
1543  * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1544  *
1545  * @ctrl: The v4l2_ctrl pointer.
1546  * @elems: The number of elements to compare.
1547  * @ptr1: A v4l2 control value.
1548  * @ptr2: A v4l2 control value.
1549  *
1550  * Return: true if values are equal, otherwise false.
1551  */
1552 bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl, u32 elems,
1553 			     union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1554 
1555 /**
1556  * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1557  *
1558  * @ctrl: The v4l2_ctrl pointer.
1559  * @from_idx: Starting element index.
1560  * @elems: The number of elements to initialize.
1561  * @ptr: The v4l2 control value.
1562  *
1563  * Return: void
1564  */
1565 void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1566 			    u32 elems, union v4l2_ctrl_ptr ptr);
1567 
1568 /**
1569  * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1570  *
1571  * @ctrl: The v4l2_ctrl pointer.
1572  *
1573  * Return: void
1574  */
1575 void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1576 
1577 /**
1578  * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1579  *
1580  * @ctrl: The v4l2_ctrl pointer.
1581  * @elems: The number of elements in the control.
1582  * @ptr: The v4l2 control value.
1583  *
1584  * Return: 0 on success, a negative error code on failure.
1585  */
1586 int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, u32 elems,
1587 			       union v4l2_ctrl_ptr ptr);
1588 
1589 #endif
1590