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 <linux/android_kabi.h>
15 #include <media/media-request.h>
16 
17 /* forward references */
18 struct file;
19 struct poll_table_struct;
20 struct v4l2_ctrl;
21 struct v4l2_ctrl_handler;
22 struct v4l2_ctrl_helper;
23 struct v4l2_fh;
24 struct v4l2_fwnode_device_properties;
25 struct v4l2_subdev;
26 struct v4l2_subscribed_event;
27 struct video_device;
28 
29 /**
30  * union v4l2_ctrl_ptr - A pointer to a control value.
31  * @p_s32:			Pointer to a 32-bit signed value.
32  * @p_s64:			Pointer to a 64-bit signed value.
33  * @p_u8:			Pointer to a 8-bit unsigned value.
34  * @p_u16:			Pointer to a 16-bit unsigned value.
35  * @p_u32:			Pointer to a 32-bit unsigned value.
36  * @p_char:			Pointer to a string.
37  * @p_mpeg2_sequence:		Pointer to a MPEG2 sequence structure.
38  * @p_mpeg2_picture:		Pointer to a MPEG2 picture structure.
39  * @p_mpeg2_quantisation:	Pointer to a MPEG2 quantisation data structure.
40  * @p_fwht_params:		Pointer to a FWHT stateless parameters structure.
41  * @p_h264_sps:			Pointer to a struct v4l2_ctrl_h264_sps.
42  * @p_h264_pps:			Pointer to a struct v4l2_ctrl_h264_pps.
43  * @p_h264_scaling_matrix:	Pointer to a struct v4l2_ctrl_h264_scaling_matrix.
44  * @p_h264_slice_params:	Pointer to a struct v4l2_ctrl_h264_slice_params.
45  * @p_h264_decode_params:	Pointer to a struct v4l2_ctrl_h264_decode_params.
46  * @p_h264_pred_weights:	Pointer to a struct v4l2_ctrl_h264_pred_weights.
47  * @p_vp8_frame:		Pointer to a VP8 frame params structure.
48  * @p_vp9_compressed_hdr_probs:	Pointer to a VP9 frame compressed header probs structure.
49  * @p_vp9_frame:		Pointer to a VP9 frame params structure.
50  * @p_hevc_sps:			Pointer to an HEVC sequence parameter set structure.
51  * @p_hevc_pps:			Pointer to an HEVC picture parameter set structure.
52  * @p_hevc_slice_params:	Pointer to an HEVC slice parameters structure.
53  * @p_hdr10_cll:		Pointer to an HDR10 Content Light Level structure.
54  * @p_hdr10_mastering:		Pointer to an HDR10 Mastering Display structure.
55  * @p_area:			Pointer to an area.
56  * @p_av1_sequence:		Pointer to an AV1 sequence structure.
57  * @p_av1_tile_group_entry:	Pointer to an AV1 tile group entry structure.
58  * @p_av1_frame:		Pointer to an AV1 frame structure.
59  * @p_av1_film_grain:		Pointer to an AV1 film grain structure.
60  * @p_rect:			Pointer to a rectangle.
61  * @p:				Pointer to a compound value.
62  * @p_const:			Pointer to a constant compound value.
63  */
64 union v4l2_ctrl_ptr {
65 	s32 *p_s32;
66 	s64 *p_s64;
67 	u8 *p_u8;
68 	u16 *p_u16;
69 	u32 *p_u32;
70 	char *p_char;
71 	struct v4l2_ctrl_mpeg2_sequence *p_mpeg2_sequence;
72 	struct v4l2_ctrl_mpeg2_picture *p_mpeg2_picture;
73 	struct v4l2_ctrl_mpeg2_quantisation *p_mpeg2_quantisation;
74 	struct v4l2_ctrl_fwht_params *p_fwht_params;
75 	struct v4l2_ctrl_h264_sps *p_h264_sps;
76 	struct v4l2_ctrl_h264_pps *p_h264_pps;
77 	struct v4l2_ctrl_h264_scaling_matrix *p_h264_scaling_matrix;
78 	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
79 	struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
80 	struct v4l2_ctrl_h264_pred_weights *p_h264_pred_weights;
81 	struct v4l2_ctrl_vp8_frame *p_vp8_frame;
82 	struct v4l2_ctrl_hevc_sps *p_hevc_sps;
83 	struct v4l2_ctrl_hevc_pps *p_hevc_pps;
84 	struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
85 	struct v4l2_ctrl_vp9_compressed_hdr *p_vp9_compressed_hdr_probs;
86 	struct v4l2_ctrl_vp9_frame *p_vp9_frame;
87 	struct v4l2_ctrl_hdr10_cll_info *p_hdr10_cll;
88 	struct v4l2_ctrl_hdr10_mastering_display *p_hdr10_mastering;
89 	struct v4l2_area *p_area;
90 	struct v4l2_ctrl_av1_sequence *p_av1_sequence;
91 	struct v4l2_ctrl_av1_tile_group_entry *p_av1_tile_group_entry;
92 	struct v4l2_ctrl_av1_frame *p_av1_frame;
93 	struct v4l2_ctrl_av1_film_grain *p_av1_film_grain;
94 	struct v4l2_rect *p_rect;
95 	void *p;
96 	const void *p_const;
97 
98 	ANDROID_KABI_RESERVE(1);
99 	ANDROID_KABI_RESERVE(2);
100 };
101 
102 /**
103  * v4l2_ctrl_ptr_create() - Helper function to return a v4l2_ctrl_ptr from a
104  * void pointer
105  * @ptr:	The void pointer
106  */
v4l2_ctrl_ptr_create(void * ptr)107 static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_create(void *ptr)
108 {
109 	union v4l2_ctrl_ptr p = { .p = ptr };
110 
111 	return p;
112 }
113 
114 /**
115  * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
116  *
117  * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
118  *		for volatile (and usually read-only) controls such as a control
119  *		that returns the current signal strength which changes
120  *		continuously.
121  *		If not set, then the currently cached value will be returned.
122  * @try_ctrl:	Test whether the control's value is valid. Only relevant when
123  *		the usual min/max/step checks are not sufficient.
124  * @s_ctrl:	Actually set the new control value. s_ctrl is compulsory. The
125  *		ctrl->handler->lock is held when these ops are called, so no
126  *		one else can access controls owned by that handler.
127  */
128 struct v4l2_ctrl_ops {
129 	int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
130 	int (*try_ctrl)(struct v4l2_ctrl *ctrl);
131 	int (*s_ctrl)(struct v4l2_ctrl *ctrl);
132 
133 	ANDROID_KABI_RESERVE(1);
134 };
135 
136 /**
137  * struct v4l2_ctrl_type_ops - The control type operations that the driver
138  *			       has to provide.
139  *
140  * @equal: return true if all ctrl->elems array elements are equal.
141  * @init: initialize the value for array elements from from_idx to ctrl->elems.
142  * @minimum: set the value to the minimum value of the control.
143  * @maximum: set the value to the maximum value of the control.
144  * @log: log the value.
145  * @validate: validate the value for ctrl->new_elems array elements.
146  *	Return 0 on success and a negative value otherwise.
147  */
148 struct v4l2_ctrl_type_ops {
149 	bool (*equal)(const struct v4l2_ctrl *ctrl,
150 		      union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
151 	void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx,
152 		     union v4l2_ctrl_ptr ptr);
153 	void (*minimum)(const struct v4l2_ctrl *ctrl, u32 idx,
154 			union v4l2_ctrl_ptr ptr);
155 	void (*maximum)(const struct v4l2_ctrl *ctrl, u32 idx,
156 			union v4l2_ctrl_ptr ptr);
157 	void (*log)(const struct v4l2_ctrl *ctrl);
158 	int (*validate)(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
159 
160 	ANDROID_KABI_RESERVE(1);
161 };
162 
163 /**
164  * typedef v4l2_ctrl_notify_fnc - typedef for a notify argument with a function
165  *	that should be called when a control value has changed.
166  *
167  * @ctrl: pointer to struct &v4l2_ctrl
168  * @priv: control private data
169  *
170  * This typedef definition is used as an argument to v4l2_ctrl_notify()
171  * and as an argument at struct &v4l2_ctrl_handler.
172  */
173 typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
174 
175 /**
176  * struct v4l2_ctrl - The control structure.
177  *
178  * @node:	The list node.
179  * @ev_subs:	The list of control event subscriptions.
180  * @handler:	The handler that owns the control.
181  * @cluster:	Point to start of cluster array.
182  * @ncontrols:	Number of controls in cluster array.
183  * @done:	Internal flag: set for each processed control.
184  * @is_new:	Set when the user specified a new value for this control. It
185  *		is also set when called from v4l2_ctrl_handler_setup(). Drivers
186  *		should never set this flag.
187  * @has_changed: Set when the current value differs from the new value. Drivers
188  *		should never use this flag.
189  * @is_private: If set, then this control is private to its handler and it
190  *		will not be added to any other handlers. Drivers can set
191  *		this flag.
192  * @is_auto:   If set, then this control selects whether the other cluster
193  *		members are in 'automatic' mode or 'manual' mode. This is
194  *		used for autogain/gain type clusters. Drivers should never
195  *		set this flag directly.
196  * @is_int:    If set, then this control has a simple integer value (i.e. it
197  *		uses ctrl->val).
198  * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING.
199  * @is_ptr:	If set, then this control is an array and/or has type >=
200  *		%V4L2_CTRL_COMPOUND_TYPES
201  *		and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct
202  *		v4l2_ext_control uses field p to point to the data.
203  * @is_array: If set, then this control contains an N-dimensional array.
204  * @is_dyn_array: If set, then this control contains a dynamically sized 1-dimensional array.
205  *		If this is set, then @is_array is also set.
206  * @has_volatiles: If set, then one or more members of the cluster are volatile.
207  *		Drivers should never touch this flag.
208  * @call_notify: If set, then call the handler's notify function whenever the
209  *		control's value changes.
210  * @manual_mode_value: If the is_auto flag is set, then this is the value
211  *		of the auto control that determines if that control is in
212  *		manual mode. So if the value of the auto control equals this
213  *		value, then the whole cluster is in manual mode. Drivers should
214  *		never set this flag directly.
215  * @ops:	The control ops.
216  * @type_ops:	The control type ops.
217  * @id:	The control ID.
218  * @name:	The control name.
219  * @type:	The control type.
220  * @minimum:	The control's minimum value.
221  * @maximum:	The control's maximum value.
222  * @default_value: The control's default value.
223  * @step:	The control's step value for non-menu controls.
224  * @elems:	The number of elements in the N-dimensional array.
225  * @elem_size:	The size in bytes of the control.
226  * @new_elems:	The number of elements in p_new. This is the same as @elems,
227  *		except for dynamic arrays. In that case it is in the range of
228  *		1 to @p_array_alloc_elems.
229  * @dims:	The size of each dimension.
230  * @nr_of_dims:The number of dimensions in @dims.
231  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
232  *		easy to skip menu items that are not valid. If bit X is set,
233  *		then menu item X is skipped. Of course, this only works for
234  *		menus with <= 32 menu items. There are no menus that come
235  *		close to that number, so this is OK. Should we ever need more,
236  *		then this will have to be extended to a u64 or a bit array.
237  * @qmenu:	A const char * array for all menu items. Array entries that are
238  *		empty strings ("") correspond to non-existing menu items (this
239  *		is in addition to the menu_skip_mask above). The last entry
240  *		must be NULL.
241  *		Used only if the @type is %V4L2_CTRL_TYPE_MENU.
242  * @qmenu_int:	A 64-bit integer array for with integer menu items.
243  *		The size of array must be equal to the menu size, e. g.:
244  *		:math:`ceil(\frac{maximum - minimum}{step}) + 1`.
245  *		Used only if the @type is %V4L2_CTRL_TYPE_INTEGER_MENU.
246  * @flags:	The control's flags.
247  * @priv:	The control's private pointer. For use by the driver. It is
248  *		untouched by the control framework. Note that this pointer is
249  *		not freed when the control is deleted. Should this be needed
250  *		then a new internal bitfield can be added to tell the framework
251  *		to free this pointer.
252  * @p_array:	Pointer to the allocated array. Only valid if @is_array is true.
253  * @p_array_alloc_elems: The number of elements in the allocated
254  *		array for both the cur and new values. So @p_array is actually
255  *		sized for 2 * @p_array_alloc_elems * @elem_size. Only valid if
256  *		@is_array is true.
257  * @cur:	Structure to store the current value.
258  * @cur.val:	The control's current value, if the @type is represented via
259  *		a u32 integer (see &enum v4l2_ctrl_type).
260  * @val:	The control's new s32 value.
261  * @p_def:	The control's default value represented via a union which
262  *		provides a standard way of accessing control types
263  *		through a pointer (for compound controls only).
264  * @p_min:	The control's minimum value represented via a union which
265  *		provides a standard way of accessing control types
266  *		through a pointer (for compound controls only).
267  * @p_max:	The control's maximum value represented via a union which
268  *		provides a standard way of accessing control types
269  *		through a pointer (for compound controls only).
270  * @p_cur:	The control's current value represented via a union which
271  *		provides a standard way of accessing control types
272  *		through a pointer.
273  * @p_new:	The control's new value represented via a union which provides
274  *		a standard way of accessing control types
275  *		through a pointer.
276  */
277 struct v4l2_ctrl {
278 	/* Administrative fields */
279 	struct list_head node;
280 	struct list_head ev_subs;
281 	struct v4l2_ctrl_handler *handler;
282 	struct v4l2_ctrl **cluster;
283 	unsigned int ncontrols;
284 
285 	unsigned int done:1;
286 
287 	unsigned int is_new:1;
288 	unsigned int has_changed:1;
289 	unsigned int is_private:1;
290 	unsigned int is_auto:1;
291 	unsigned int is_int:1;
292 	unsigned int is_string:1;
293 	unsigned int is_ptr:1;
294 	unsigned int is_array:1;
295 	unsigned int is_dyn_array:1;
296 	unsigned int has_volatiles:1;
297 	unsigned int call_notify:1;
298 	unsigned int manual_mode_value:8;
299 
300 	const struct v4l2_ctrl_ops *ops;
301 	const struct v4l2_ctrl_type_ops *type_ops;
302 	u32 id;
303 	const char *name;
304 	enum v4l2_ctrl_type type;
305 	s64 minimum, maximum, default_value;
306 	u32 elems;
307 	u32 elem_size;
308 	u32 new_elems;
309 	u32 dims[V4L2_CTRL_MAX_DIMS];
310 	u32 nr_of_dims;
311 	union {
312 		u64 step;
313 		u64 menu_skip_mask;
314 	};
315 	union {
316 		const char * const *qmenu;
317 		const s64 *qmenu_int;
318 	};
319 	unsigned long flags;
320 	void *priv;
321 	void *p_array;
322 	u32 p_array_alloc_elems;
323 	s32 val;
324 	struct {
325 		s32 val;
326 	} cur;
327 
328 	union v4l2_ctrl_ptr p_def;
329 	union v4l2_ctrl_ptr p_min;
330 	union v4l2_ctrl_ptr p_max;
331 	union v4l2_ctrl_ptr p_new;
332 	union v4l2_ctrl_ptr p_cur;
333 
334 	ANDROID_KABI_RESERVE(1);
335 };
336 
337 /**
338  * struct v4l2_ctrl_ref - The control reference.
339  *
340  * @node:	List node for the sorted list.
341  * @next:	Single-link list node for the hash.
342  * @ctrl:	The actual control information.
343  * @helper:	Pointer to helper struct. Used internally in
344  *		``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
345  * @from_other_dev: If true, then @ctrl was defined in another
346  *		device than the &struct v4l2_ctrl_handler.
347  * @req_done:	Internal flag: if the control handler containing this control
348  *		reference is bound to a media request, then this is set when
349  *		the control has been applied. This prevents applying controls
350  *		from a cluster with multiple controls twice (when the first
351  *		control of a cluster is applied, they all are).
352  * @p_req_valid: If set, then p_req contains the control value for the request.
353  * @p_req_array_enomem: If set, then p_req is invalid since allocating space for
354  *		an array failed. Attempting to read this value shall
355  *		result in ENOMEM. Only valid if ctrl->is_array is true.
356  * @p_req_array_alloc_elems: The number of elements allocated for the
357  *		array. Only valid if @p_req_valid and ctrl->is_array are
358  *		true.
359  * @p_req_elems: The number of elements in @p_req. This is the same as
360  *		ctrl->elems, except for dynamic arrays. In that case it is in
361  *		the range of 1 to @p_req_array_alloc_elems. Only valid if
362  *		@p_req_valid is true.
363  * @p_req:	If the control handler containing this control reference
364  *		is bound to a media request, then this points to the
365  *		value of the control that must be applied when the request
366  *		is executed, or to the value of the control at the time
367  *		that the request was completed. If @p_req_valid is false,
368  *		then this control was never set for this request and the
369  *		control will not be updated when this request is applied.
370  *
371  * Each control handler has a list of these refs. The list_head is used to
372  * keep a sorted-by-control-ID list of all controls, while the next pointer
373  * is used to link the control in the hash's bucket.
374  */
375 struct v4l2_ctrl_ref {
376 	struct list_head node;
377 	struct v4l2_ctrl_ref *next;
378 	struct v4l2_ctrl *ctrl;
379 	struct v4l2_ctrl_helper *helper;
380 	bool from_other_dev;
381 	bool req_done;
382 	bool p_req_valid;
383 	bool p_req_array_enomem;
384 	u32 p_req_array_alloc_elems;
385 	u32 p_req_elems;
386 	union v4l2_ctrl_ptr p_req;
387 
388 	ANDROID_KABI_RESERVE(1);
389 };
390 
391 /**
392  * struct v4l2_ctrl_handler - The control handler keeps track of all the
393  *	controls: both the controls owned by the handler and those inherited
394  *	from other handlers.
395  *
396  * @_lock:	Default for "lock".
397  * @lock:	Lock to control access to this handler and its controls.
398  *		May be replaced by the user right after init.
399  * @ctrls:	The list of controls owned by this handler.
400  * @ctrl_refs:	The list of control references.
401  * @cached:	The last found control reference. It is common that the same
402  *		control is needed multiple times, so this is a simple
403  *		optimization.
404  * @buckets:	Buckets for the hashing. Allows for quick control lookup.
405  * @notify:	A notify callback that is called whenever the control changes
406  *		value.
407  *		Note that the handler's lock is held when the notify function
408  *		is called!
409  * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
410  * @nr_of_buckets: Total number of buckets in the array.
411  * @error:	The error code of the first failed control addition.
412  * @request_is_queued: True if the request was queued.
413  * @requests:	List to keep track of open control handler request objects.
414  *		For the parent control handler (@req_obj.ops == NULL) this
415  *		is the list header. When the parent control handler is
416  *		removed, it has to unbind and put all these requests since
417  *		they refer to the parent.
418  * @requests_queued: List of the queued requests. This determines the order
419  *		in which these controls are applied. Once the request is
420  *		completed it is removed from this list.
421  * @req_obj:	The &struct media_request_object, used to link into a
422  *		&struct media_request. This request object has a refcount.
423  */
424 struct v4l2_ctrl_handler {
425 	struct mutex _lock;
426 	struct mutex *lock;
427 	struct list_head ctrls;
428 	struct list_head ctrl_refs;
429 	struct v4l2_ctrl_ref *cached;
430 	struct v4l2_ctrl_ref **buckets;
431 	v4l2_ctrl_notify_fnc notify;
432 	void *notify_priv;
433 	u16 nr_of_buckets;
434 	int error;
435 	bool request_is_queued;
436 	struct list_head requests;
437 	struct list_head requests_queued;
438 	struct media_request_object req_obj;
439 
440 	ANDROID_KABI_RESERVE(1);
441 };
442 
443 /**
444  * struct v4l2_ctrl_config - Control configuration structure.
445  *
446  * @ops:	The control ops.
447  * @type_ops:	The control type ops. Only needed for compound controls.
448  * @id:	The control ID.
449  * @name:	The control name.
450  * @type:	The control type.
451  * @min:	The control's minimum value.
452  * @max:	The control's maximum value.
453  * @step:	The control's step value for non-menu controls.
454  * @def:	The control's default value.
455  * @p_def:	The control's default value for compound controls.
456  * @p_min:	The control's minimum value for compound controls.
457  * @p_max:	The control's maximum value for compound controls.
458  * @dims:	The size of each dimension.
459  * @elem_size:	The size in bytes of the control.
460  * @flags:	The control's flags.
461  * @menu_skip_mask: The control's skip mask for menu controls. This makes it
462  *		easy to skip menu items that are not valid. If bit X is set,
463  *		then menu item X is skipped. Of course, this only works for
464  *		menus with <= 64 menu items. There are no menus that come
465  *		close to that number, so this is OK. Should we ever need more,
466  *		then this will have to be extended to a bit array.
467  * @qmenu:	A const char * array for all menu items. Array entries that are
468  *		empty strings ("") correspond to non-existing menu items (this
469  *		is in addition to the menu_skip_mask above). The last entry
470  *		must be NULL.
471  * @qmenu_int:	A const s64 integer array for all menu items of the type
472  *		V4L2_CTRL_TYPE_INTEGER_MENU.
473  * @is_private: If set, then this control is private to its handler and it
474  *		will not be added to any other handlers.
475  */
476 struct v4l2_ctrl_config {
477 	const struct v4l2_ctrl_ops *ops;
478 	const struct v4l2_ctrl_type_ops *type_ops;
479 	u32 id;
480 	const char *name;
481 	enum v4l2_ctrl_type type;
482 	s64 min;
483 	s64 max;
484 	u64 step;
485 	s64 def;
486 	union v4l2_ctrl_ptr p_def;
487 	union v4l2_ctrl_ptr p_min;
488 	union v4l2_ctrl_ptr p_max;
489 	u32 dims[V4L2_CTRL_MAX_DIMS];
490 	u32 elem_size;
491 	u32 flags;
492 	u64 menu_skip_mask;
493 	const char * const *qmenu;
494 	const s64 *qmenu_int;
495 	unsigned int is_private:1;
496 
497 	ANDROID_KABI_RESERVE(1);
498 };
499 
500 /**
501  * v4l2_ctrl_fill - Fill in the control fields based on the control ID.
502  *
503  * @id: ID of the control
504  * @name: pointer to be filled with a string with the name of the control
505  * @type: pointer for storing the type of the control
506  * @min: pointer for storing the minimum value for the control
507  * @max: pointer for storing the maximum value for the control
508  * @step: pointer for storing the control step
509  * @def: pointer for storing the default value for the control
510  * @flags: pointer for storing the flags to be used on the control
511  *
512  * This works for all standard V4L2 controls.
513  * For non-standard controls it will only fill in the given arguments
514  * and @name content will be set to %NULL.
515  *
516  * This function will overwrite the contents of @name, @type and @flags.
517  * The contents of @min, @max, @step and @def may be modified depending on
518  * the type.
519  *
520  * .. note::
521  *
522  *    Do not use in drivers! It is used internally for backwards compatibility
523  *    control handling only. Once all drivers are converted to use the new
524  *    control framework this function will no longer be exported.
525  */
526 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
527 		    s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags);
528 
529 
530 /**
531  * v4l2_ctrl_handler_init_class() - Initialize the control handler.
532  * @hdl:	The control handler.
533  * @nr_of_controls_hint: A hint of how many controls this handler is
534  *		expected to refer to. This is the total number, so including
535  *		any inherited controls. It doesn't have to be precise, but if
536  *		it is way off, then you either waste memory (too many buckets
537  *		are allocated) or the control lookup becomes slower (not enough
538  *		buckets are allocated, so there are more slow list lookups).
539  *		It will always work, though.
540  * @key:	Used by the lock validator if CONFIG_LOCKDEP is set.
541  * @name:	Used by the lock validator if CONFIG_LOCKDEP is set.
542  *
543  * .. attention::
544  *
545  *    Never use this call directly, always use the v4l2_ctrl_handler_init()
546  *    macro that hides the @key and @name arguments.
547  *
548  * Return: returns an error if the buckets could not be allocated. This
549  * error will also be stored in @hdl->error.
550  */
551 int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl,
552 				 unsigned int nr_of_controls_hint,
553 				 struct lock_class_key *key, const char *name);
554 
555 #ifdef CONFIG_LOCKDEP
556 
557 /**
558  * v4l2_ctrl_handler_init - helper function to create a static struct
559  *	 &lock_class_key and calls v4l2_ctrl_handler_init_class()
560  *
561  * @hdl:	The control handler.
562  * @nr_of_controls_hint: A hint of how many controls this handler is
563  *		expected to refer to. This is the total number, so including
564  *		any inherited controls. It doesn't have to be precise, but if
565  *		it is way off, then you either waste memory (too many buckets
566  *		are allocated) or the control lookup becomes slower (not enough
567  *		buckets are allocated, so there are more slow list lookups).
568  *		It will always work, though.
569  *
570  * This helper function creates a static struct &lock_class_key and
571  * calls v4l2_ctrl_handler_init_class(), providing a proper name for the lock
572  * validador.
573  *
574  * Use this helper function to initialize a control handler.
575  */
576 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
577 (									\
578 	({								\
579 		static struct lock_class_key _key;			\
580 		v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint,	\
581 					&_key,				\
582 					KBUILD_BASENAME ":"		\
583 					__stringify(__LINE__) ":"	\
584 					"(" #hdl ")->_lock");		\
585 	})								\
586 )
587 #else
588 #define v4l2_ctrl_handler_init(hdl, nr_of_controls_hint)		\
589 	v4l2_ctrl_handler_init_class(hdl, nr_of_controls_hint, NULL, NULL)
590 #endif
591 
592 /**
593  * v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
594  * the control list.
595  * @hdl:	The control handler.
596  *
597  * Does nothing if @hdl == NULL.
598  */
599 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
600 
601 /**
602  * v4l2_ctrl_lock() - Helper function to lock the handler
603  * associated with the control.
604  * @ctrl:	The control to lock.
605  */
v4l2_ctrl_lock(struct v4l2_ctrl * ctrl)606 static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
607 {
608 	mutex_lock(ctrl->handler->lock);
609 }
610 
611 /**
612  * v4l2_ctrl_unlock() - Helper function to unlock the handler
613  * associated with the control.
614  * @ctrl:	The control to unlock.
615  */
v4l2_ctrl_unlock(struct v4l2_ctrl * ctrl)616 static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
617 {
618 	mutex_unlock(ctrl->handler->lock);
619 }
620 
621 /**
622  * __v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
623  * to the handler to initialize the hardware to the current control values. The
624  * caller is responsible for acquiring the control handler mutex on behalf of
625  * __v4l2_ctrl_handler_setup().
626  * @hdl:	The control handler.
627  *
628  * Button controls will be skipped, as are read-only controls.
629  *
630  * If @hdl == NULL, then this just returns 0.
631  */
632 int __v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
633 
634 /**
635  * v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
636  * to the handler to initialize the hardware to the current control values.
637  * @hdl:	The control handler.
638  *
639  * Button controls will be skipped, as are read-only controls.
640  *
641  * If @hdl == NULL, then this just returns 0.
642  */
643 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
644 
645 /**
646  * v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
647  * @hdl:	The control handler.
648  * @prefix:	The prefix to use when logging the control values. If the
649  *		prefix does not end with a space, then ": " will be added
650  *		after the prefix. If @prefix == NULL, then no prefix will be
651  *		used.
652  *
653  * For use with VIDIOC_LOG_STATUS.
654  *
655  * Does nothing if @hdl == NULL.
656  */
657 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
658 				  const char *prefix);
659 
660 /**
661  * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
662  *	control.
663  *
664  * @hdl:	The control handler.
665  * @cfg:	The control's configuration data.
666  * @priv:	The control's driver-specific private data.
667  *
668  * If the &v4l2_ctrl struct could not be allocated then NULL is returned
669  * and @hdl->error is set to the error code (if it wasn't set already).
670  */
671 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
672 				       const struct v4l2_ctrl_config *cfg,
673 				       void *priv);
674 
675 /**
676  * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu
677  *	control.
678  *
679  * @hdl:	The control handler.
680  * @ops:	The control ops.
681  * @id:		The control ID.
682  * @min:	The control's minimum value.
683  * @max:	The control's maximum value.
684  * @step:	The control's step value
685  * @def:	The control's default value.
686  *
687  * If the &v4l2_ctrl struct could not be allocated, or the control
688  * ID is not known, then NULL is returned and @hdl->error is set to the
689  * appropriate error code (if it wasn't set already).
690  *
691  * If @id refers to a menu control, then this function will return NULL.
692  *
693  * Use v4l2_ctrl_new_std_menu() when adding menu controls.
694  */
695 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
696 				    const struct v4l2_ctrl_ops *ops,
697 				    u32 id, s64 min, s64 max, u64 step,
698 				    s64 def);
699 
700 /**
701  * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2
702  *	menu control.
703  *
704  * @hdl:	The control handler.
705  * @ops:	The control ops.
706  * @id:		The control ID.
707  * @max:	The control's maximum value.
708  * @mask:	The control's skip mask for menu controls. This makes it
709  *		easy to skip menu items that are not valid. If bit X is set,
710  *		then menu item X is skipped. Of course, this only works for
711  *		menus with <= 64 menu items. There are no menus that come
712  *		close to that number, so this is OK. Should we ever need more,
713  *		then this will have to be extended to a bit array.
714  * @def:	The control's default value.
715  *
716  * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
717  * determines which menu items are to be skipped.
718  *
719  * If @id refers to a non-menu control, then this function will return NULL.
720  */
721 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
722 					 const struct v4l2_ctrl_ops *ops,
723 					 u32 id, u8 max, u64 mask, u8 def);
724 
725 /**
726  * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control
727  *	with driver specific menu.
728  *
729  * @hdl:	The control handler.
730  * @ops:	The control ops.
731  * @id:	The control ID.
732  * @max:	The control's maximum value.
733  * @mask:	The control's skip mask for menu controls. This makes it
734  *		easy to skip menu items that are not valid. If bit X is set,
735  *		then menu item X is skipped. Of course, this only works for
736  *		menus with <= 64 menu items. There are no menus that come
737  *		close to that number, so this is OK. Should we ever need more,
738  *		then this will have to be extended to a bit array.
739  * @def:	The control's default value.
740  * @qmenu:	The new menu.
741  *
742  * Same as v4l2_ctrl_new_std_menu(), but @qmenu will be the driver specific
743  * menu of this control.
744  *
745  */
746 struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
747 					       const struct v4l2_ctrl_ops *ops,
748 					       u32 id, u8 max,
749 					       u64 mask, u8 def,
750 					       const char * const *qmenu);
751 
752 /**
753  * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
754  *      compound control.
755  *
756  * @hdl:       The control handler.
757  * @ops:       The control ops.
758  * @id:        The control ID.
759  * @p_def:     The control's default value.
760  * @p_min:     The control's minimum value.
761  * @p_max:     The control's maximum value.
762  *
763  * Same as v4l2_ctrl_new_std(), but with support for compound controls.
764  * To fill in the @p_def, @p_min and @p_max fields, use v4l2_ctrl_ptr_create()
765  * to convert a pointer to a const union v4l2_ctrl_ptr.
766  * Use v4l2_ctrl_ptr_create(NULL) if you want the default, minimum or maximum
767  * value of the compound control to be all zeroes.
768  * If the compound control does not set the ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX``
769  * flag, then it does not has minimum and maximum values. In that case just use
770  * v4l2_ctrl_ptr_create(NULL) for the @p_min and @p_max arguments.
771  *
772  */
773 struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
774 					     const struct v4l2_ctrl_ops *ops,
775 					     u32 id,
776 					     const union v4l2_ctrl_ptr p_def,
777 					     const union v4l2_ctrl_ptr p_min,
778 					     const union v4l2_ctrl_ptr p_max);
779 
780 /**
781  * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
782  *
783  * @hdl:	The control handler.
784  * @ops:	The control ops.
785  * @id:	The control ID.
786  * @max:	The control's maximum value.
787  * @def:	The control's default value.
788  * @qmenu_int:	The control's menu entries.
789  *
790  * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionally
791  * takes as an argument an array of integers determining the menu items.
792  *
793  * If @id refers to a non-integer-menu control, then this function will
794  * return %NULL.
795  */
796 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
797 					 const struct v4l2_ctrl_ops *ops,
798 					 u32 id, u8 max, u8 def,
799 					 const s64 *qmenu_int);
800 
801 /**
802  * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
803  *	used when adding a control handler.
804  *
805  * @ctrl: pointer to struct &v4l2_ctrl.
806  */
807 
808 typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl);
809 
810 /**
811  * v4l2_ctrl_add_handler() - Add all controls from handler @add to
812  *	handler @hdl.
813  *
814  * @hdl:	The control handler.
815  * @add:	The control handler whose controls you want to add to
816  *		the @hdl control handler.
817  * @filter:	This function will filter which controls should be added.
818  * @from_other_dev: If true, then the controls in @add were defined in another
819  *		device than @hdl.
820  *
821  * Does nothing if either of the two handlers is a NULL pointer.
822  * If @filter is NULL, then all controls are added. Otherwise only those
823  * controls for which @filter returns true will be added.
824  * In case of an error @hdl->error will be set to the error code (if it
825  * wasn't set already).
826  */
827 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
828 			  struct v4l2_ctrl_handler *add,
829 			  v4l2_ctrl_filter filter,
830 			  bool from_other_dev);
831 
832 /**
833  * v4l2_ctrl_radio_filter() - Standard filter for radio controls.
834  *
835  * @ctrl:	The control that is filtered.
836  *
837  * This will return true for any controls that are valid for radio device
838  * nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
839  * transmitter class controls.
840  *
841  * This function is to be used with v4l2_ctrl_add_handler().
842  */
843 bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
844 
845 /**
846  * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging
847  *	to that cluster.
848  *
849  * @ncontrols:	The number of controls in this cluster.
850  * @controls:	The cluster control array of size @ncontrols.
851  */
852 void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls);
853 
854 
855 /**
856  * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging
857  *	to that cluster and set it up for autofoo/foo-type handling.
858  *
859  * @ncontrols:	The number of controls in this cluster.
860  * @controls:	The cluster control array of size @ncontrols. The first control
861  *		must be the 'auto' control (e.g. autogain, autoexposure, etc.)
862  * @manual_val: The value for the first control in the cluster that equals the
863  *		manual setting.
864  * @set_volatile: If true, then all controls except the first auto control will
865  *		be volatile.
866  *
867  * Use for control groups where one control selects some automatic feature and
868  * the other controls are only active whenever the automatic feature is turned
869  * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
870  * red and blue balance, etc.
871  *
872  * The behavior of such controls is as follows:
873  *
874  * When the autofoo control is set to automatic, then any manual controls
875  * are set to inactive and any reads will call g_volatile_ctrl (if the control
876  * was marked volatile).
877  *
878  * When the autofoo control is set to manual, then any manual controls will
879  * be marked active, and any reads will just return the current value without
880  * going through g_volatile_ctrl.
881  *
882  * In addition, this function will set the %V4L2_CTRL_FLAG_UPDATE flag
883  * on the autofoo control and %V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
884  * if autofoo is in auto mode.
885  */
886 void v4l2_ctrl_auto_cluster(unsigned int ncontrols,
887 			    struct v4l2_ctrl **controls,
888 			    u8 manual_val, bool set_volatile);
889 
890 
891 /**
892  * v4l2_ctrl_find() - Find a control with the given ID.
893  *
894  * @hdl:	The control handler.
895  * @id:	The control ID to find.
896  *
897  * If @hdl == NULL this will return NULL as well. Will lock the handler so
898  * do not use from inside &v4l2_ctrl_ops.
899  */
900 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
901 
902 /**
903  * v4l2_ctrl_activate() - Make the control active or inactive.
904  * @ctrl:	The control to (de)activate.
905  * @active:	True if the control should become active.
906  *
907  * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
908  * Does nothing if @ctrl == NULL.
909  * This will usually be called from within the s_ctrl op.
910  * The V4L2_EVENT_CTRL event will be generated afterwards.
911  *
912  * This function assumes that the control handler is locked.
913  */
914 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
915 
916 /**
917  * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.
918  *
919  * @ctrl:	The control to (de)activate.
920  * @grabbed:	True if the control should become grabbed.
921  *
922  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
923  * Does nothing if @ctrl == NULL.
924  * The V4L2_EVENT_CTRL event will be generated afterwards.
925  * This will usually be called when starting or stopping streaming in the
926  * driver.
927  *
928  * This function assumes that the control handler is locked by the caller.
929  */
930 void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
931 
932 /**
933  * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
934  *
935  * @ctrl:	The control to (de)activate.
936  * @grabbed:	True if the control should become grabbed.
937  *
938  * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
939  * Does nothing if @ctrl == NULL.
940  * The V4L2_EVENT_CTRL event will be generated afterwards.
941  * This will usually be called when starting or stopping streaming in the
942  * driver.
943  *
944  * This function assumes that the control handler is not locked and will
945  * take the lock itself.
946  */
v4l2_ctrl_grab(struct v4l2_ctrl * ctrl,bool grabbed)947 static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
948 {
949 	if (!ctrl)
950 		return;
951 
952 	v4l2_ctrl_lock(ctrl);
953 	__v4l2_ctrl_grab(ctrl, grabbed);
954 	v4l2_ctrl_unlock(ctrl);
955 }
956 
957 /**
958  *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()
959  *
960  * @ctrl:	The control to update.
961  * @min:	The control's minimum value.
962  * @max:	The control's maximum value.
963  * @step:	The control's step value
964  * @def:	The control's default value.
965  *
966  * Update the range of a control on the fly. This works for control types
967  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
968  * @step value is interpreted as a menu_skip_mask.
969  *
970  * An error is returned if one of the range arguments is invalid for this
971  * control type.
972  *
973  * The caller is responsible for acquiring the control handler mutex on behalf
974  * of __v4l2_ctrl_modify_range().
975  */
976 int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
977 			     s64 min, s64 max, u64 step, s64 def);
978 
979 /**
980  * v4l2_ctrl_modify_range() - Update the range of a control.
981  *
982  * @ctrl:	The control to update.
983  * @min:	The control's minimum value.
984  * @max:	The control's maximum value.
985  * @step:	The control's step value
986  * @def:	The control's default value.
987  *
988  * Update the range of a control on the fly. This works for control types
989  * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the
990  * @step value is interpreted as a menu_skip_mask.
991  *
992  * An error is returned if one of the range arguments is invalid for this
993  * control type.
994  *
995  * This function assumes that the control handler is not locked and will
996  * take the lock itself.
997  */
v4l2_ctrl_modify_range(struct v4l2_ctrl * ctrl,s64 min,s64 max,u64 step,s64 def)998 static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
999 					 s64 min, s64 max, u64 step, s64 def)
1000 {
1001 	int rval;
1002 
1003 	v4l2_ctrl_lock(ctrl);
1004 	rval = __v4l2_ctrl_modify_range(ctrl, min, max, step, def);
1005 	v4l2_ctrl_unlock(ctrl);
1006 
1007 	return rval;
1008 }
1009 
1010 /**
1011  *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
1012  *
1013  * @ctrl:	The control to update.
1014  * @dims:	The control's new dimensions.
1015  *
1016  * Update the dimensions of an array control on the fly. The elements of the
1017  * array are reset to their default value, even if the dimensions are
1018  * unchanged.
1019  *
1020  * An error is returned if @dims is invalid for this control.
1021  *
1022  * The caller is responsible for acquiring the control handler mutex on behalf
1023  * of __v4l2_ctrl_modify_dimensions().
1024  *
1025  * Note: calling this function when the same control is used in pending requests
1026  * is untested. It should work (a request with the wrong size of the control
1027  * will drop that control silently), but it will be very confusing.
1028  */
1029 int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1030 				  u32 dims[V4L2_CTRL_MAX_DIMS]);
1031 
1032 /**
1033  * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
1034  *
1035  * @ctrl:	The control to update.
1036  * @dims:	The control's new dimensions.
1037  *
1038  * Update the dimensions of an array control on the fly. The elements of the
1039  * array are reset to their default value, even if the dimensions are
1040  * unchanged.
1041  *
1042  * An error is returned if @dims is invalid for this control type.
1043  *
1044  * This function assumes that the control handler is not locked and will
1045  * take the lock itself.
1046  *
1047  * Note: calling this function when the same control is used in pending requests
1048  * is untested. It should work (a request with the wrong size of the control
1049  * will drop that control silently), but it will be very confusing.
1050  */
v4l2_ctrl_modify_dimensions(struct v4l2_ctrl * ctrl,u32 dims[V4L2_CTRL_MAX_DIMS])1051 static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
1052 					      u32 dims[V4L2_CTRL_MAX_DIMS])
1053 {
1054 	int rval;
1055 
1056 	v4l2_ctrl_lock(ctrl);
1057 	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
1058 	v4l2_ctrl_unlock(ctrl);
1059 
1060 	return rval;
1061 }
1062 
1063 /**
1064  * v4l2_ctrl_notify() - Function to set a notify callback for a control.
1065  *
1066  * @ctrl:	The control.
1067  * @notify:	The callback function.
1068  * @priv:	The callback private handle, passed as argument to the callback.
1069  *
1070  * This function sets a callback function for the control. If @ctrl is NULL,
1071  * then it will do nothing. If @notify is NULL, then the notify callback will
1072  * be removed.
1073  *
1074  * There can be only one notify. If another already exists, then a WARN_ON
1075  * will be issued and the function will do nothing.
1076  */
1077 void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
1078 		      void *priv);
1079 
1080 /**
1081  * v4l2_ctrl_get_name() - Get the name of the control
1082  *
1083  * @id:		The control ID.
1084  *
1085  * This function returns the name of the given control ID or NULL if it isn't
1086  * a known control.
1087  */
1088 const char *v4l2_ctrl_get_name(u32 id);
1089 
1090 /**
1091  * v4l2_ctrl_get_menu() - Get the menu string array of the control
1092  *
1093  * @id:		The control ID.
1094  *
1095  * This function returns the NULL-terminated menu string array name of the
1096  * given control ID or NULL if it isn't a known menu control.
1097  */
1098 const char * const *v4l2_ctrl_get_menu(u32 id);
1099 
1100 /**
1101  * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control
1102  *
1103  * @id:		The control ID.
1104  * @len:	The size of the integer array.
1105  *
1106  * This function returns the integer array of the given control ID or NULL if it
1107  * if it isn't a known integer menu control.
1108  */
1109 const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len);
1110 
1111 /**
1112  * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from
1113  *	within a driver.
1114  *
1115  * @ctrl:	The control.
1116  *
1117  * This returns the control's value safely by going through the control
1118  * framework. This function will lock the control's handler, so it cannot be
1119  * used from within the &v4l2_ctrl_ops functions.
1120  *
1121  * This function is for integer type controls only.
1122  */
1123 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
1124 
1125 /**
1126  * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl().
1127  *
1128  * @ctrl:	The control.
1129  * @val:	The new value.
1130  *
1131  * This sets the control's new value safely by going through the control
1132  * framework. This function assumes the control's handler is already locked,
1133  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1134  *
1135  * This function is for integer type controls only.
1136  */
1137 int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
1138 
1139 /**
1140  * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from
1141  *	within a driver.
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 integer type controls only.
1150  */
v4l2_ctrl_s_ctrl(struct v4l2_ctrl * ctrl,s32 val)1151 static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
1152 {
1153 	int rval;
1154 
1155 	v4l2_ctrl_lock(ctrl);
1156 	rval = __v4l2_ctrl_s_ctrl(ctrl, val);
1157 	v4l2_ctrl_unlock(ctrl);
1158 
1159 	return rval;
1160 }
1161 
1162 /**
1163  * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value
1164  *	from within a driver.
1165  *
1166  * @ctrl:	The control.
1167  *
1168  * This returns the control's value safely by going through the control
1169  * framework. This function will lock the control's handler, so it cannot be
1170  * used from within the &v4l2_ctrl_ops functions.
1171  *
1172  * This function is for 64-bit integer type controls only.
1173  */
1174 s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl);
1175 
1176 /**
1177  * __v4l2_ctrl_s_ctrl_int64() - Unlocked variant of v4l2_ctrl_s_ctrl_int64().
1178  *
1179  * @ctrl:	The control.
1180  * @val:	The new value.
1181  *
1182  * This sets the control's new value safely by going through the control
1183  * framework. This function assumes the control's handler is already locked,
1184  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1185  *
1186  * This function is for 64-bit integer type controls only.
1187  */
1188 int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val);
1189 
1190 /**
1191  * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value
1192  *	from within a driver.
1193  *
1194  * @ctrl:	The control.
1195  * @val:	The new value.
1196  *
1197  * This sets the control's new value safely by going through the control
1198  * framework. This function will lock the control's handler, so it cannot be
1199  * used from within the &v4l2_ctrl_ops functions.
1200  *
1201  * This function is for 64-bit integer type controls only.
1202  */
v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl * ctrl,s64 val)1203 static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
1204 {
1205 	int rval;
1206 
1207 	v4l2_ctrl_lock(ctrl);
1208 	rval = __v4l2_ctrl_s_ctrl_int64(ctrl, val);
1209 	v4l2_ctrl_unlock(ctrl);
1210 
1211 	return rval;
1212 }
1213 
1214 /**
1215  * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string().
1216  *
1217  * @ctrl:	The control.
1218  * @s:		The new string.
1219  *
1220  * This sets the control's new string safely by going through the control
1221  * framework. This function assumes the control's handler is already locked,
1222  * allowing it to be used from within the &v4l2_ctrl_ops functions.
1223  *
1224  * This function is for string type controls only.
1225  */
1226 int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s);
1227 
1228 /**
1229  * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value
1230  *	 from within a driver.
1231  *
1232  * @ctrl:	The control.
1233  * @s:		The new string.
1234  *
1235  * This sets the control's new string safely by going through the control
1236  * framework. This function will lock the control's handler, so it cannot be
1237  * used from within the &v4l2_ctrl_ops functions.
1238  *
1239  * This function is for string type controls only.
1240  */
v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl * ctrl,const char * s)1241 static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
1242 {
1243 	int rval;
1244 
1245 	v4l2_ctrl_lock(ctrl);
1246 	rval = __v4l2_ctrl_s_ctrl_string(ctrl, s);
1247 	v4l2_ctrl_unlock(ctrl);
1248 
1249 	return rval;
1250 }
1251 
1252 /**
1253  * __v4l2_ctrl_s_ctrl_compound() - Unlocked variant to set a compound control
1254  *
1255  * @ctrl: The control.
1256  * @type: The type of the data.
1257  * @p:    The new compound payload.
1258  *
1259  * This sets the control's new compound payload safely by going through the
1260  * control framework. This function assumes the control's handler is already
1261  * locked, allowing it to be used from within the &v4l2_ctrl_ops functions.
1262  *
1263  * This function is for compound type controls only.
1264  */
1265 int __v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1266 				enum v4l2_ctrl_type type, const void *p);
1267 
1268 /**
1269  * v4l2_ctrl_s_ctrl_compound() - Helper function to set a compound control
1270  *	from within a driver.
1271  *
1272  * @ctrl: The control.
1273  * @type: The type of the data.
1274  * @p:    The new compound payload.
1275  *
1276  * This sets the control's new compound payload safely by going through the
1277  * control framework. This function will lock the control's handler, so it
1278  * cannot be used from within the &v4l2_ctrl_ops functions.
1279  *
1280  * This function is for compound type controls only.
1281  */
v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl * ctrl,enum v4l2_ctrl_type type,const void * p)1282 static inline int v4l2_ctrl_s_ctrl_compound(struct v4l2_ctrl *ctrl,
1283 					    enum v4l2_ctrl_type type,
1284 					    const void *p)
1285 {
1286 	int rval;
1287 
1288 	v4l2_ctrl_lock(ctrl);
1289 	rval = __v4l2_ctrl_s_ctrl_compound(ctrl, type, p);
1290 	v4l2_ctrl_unlock(ctrl);
1291 
1292 	return rval;
1293 }
1294 
1295 /* Helper defines for area type controls */
1296 #define __v4l2_ctrl_s_ctrl_area(ctrl, area) \
1297 	__v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1298 #define v4l2_ctrl_s_ctrl_area(ctrl, area) \
1299 	v4l2_ctrl_s_ctrl_compound((ctrl), V4L2_CTRL_TYPE_AREA, (area))
1300 
1301 /* Internal helper functions that deal with control events. */
1302 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
1303 
1304 /**
1305  * v4l2_ctrl_replace - Function to be used as a callback to
1306  *	&struct v4l2_subscribed_event_ops replace\(\)
1307  *
1308  * @old: pointer to struct &v4l2_event with the reported
1309  *	 event;
1310  * @new: pointer to struct &v4l2_event with the modified
1311  *	 event;
1312  */
1313 void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
1314 
1315 /**
1316  * v4l2_ctrl_merge - Function to be used as a callback to
1317  *	&struct v4l2_subscribed_event_ops merge(\)
1318  *
1319  * @old: pointer to struct &v4l2_event with the reported
1320  *	 event;
1321  * @new: pointer to struct &v4l2_event with the merged
1322  *	 event;
1323  */
1324 void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
1325 
1326 /**
1327  * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl
1328  *
1329  * @file: pointer to struct file
1330  * @fh: unused. Kept just to be compatible to the arguments expected by
1331  *	&struct v4l2_ioctl_ops.vidioc_log_status.
1332  *
1333  * Can be used as a vidioc_log_status function that just dumps all controls
1334  * associated with the filehandle.
1335  */
1336 int v4l2_ctrl_log_status(struct file *file, void *fh);
1337 
1338 /**
1339  * v4l2_ctrl_subscribe_event - Subscribes to an event
1340  *
1341  *
1342  * @fh: pointer to struct v4l2_fh
1343  * @sub: pointer to &struct v4l2_event_subscription
1344  *
1345  * Can be used as a vidioc_subscribe_event function that just subscribes
1346  * control events.
1347  */
1348 int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
1349 				const struct v4l2_event_subscription *sub);
1350 
1351 /**
1352  * v4l2_ctrl_poll - function to be used as a callback to the poll()
1353  *	That just polls for control events.
1354  *
1355  * @file: pointer to struct file
1356  * @wait: pointer to struct poll_table_struct
1357  */
1358 __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
1359 
1360 /**
1361  * v4l2_ctrl_request_setup - helper function to apply control values in a request
1362  *
1363  * @req: The request
1364  * @parent: The parent control handler ('priv' in media_request_object_find())
1365  *
1366  * This is a helper function to call the control handler's s_ctrl callback with
1367  * the control values contained in the request. Do note that this approach of
1368  * applying control values in a request is only applicable to memory-to-memory
1369  * devices.
1370  */
1371 int v4l2_ctrl_request_setup(struct media_request *req,
1372 			     struct v4l2_ctrl_handler *parent);
1373 
1374 /**
1375  * v4l2_ctrl_request_complete - Complete a control handler request object
1376  *
1377  * @req: The request
1378  * @parent: The parent control handler ('priv' in media_request_object_find())
1379  *
1380  * This function is to be called on each control handler that may have had a
1381  * request object associated with it, i.e. control handlers of a driver that
1382  * supports requests.
1383  *
1384  * The function first obtains the values of any volatile controls in the control
1385  * handler and attach them to the request. Then, the function completes the
1386  * request object.
1387  */
1388 void v4l2_ctrl_request_complete(struct media_request *req,
1389 				struct v4l2_ctrl_handler *parent);
1390 
1391 /**
1392  * v4l2_ctrl_request_hdl_find - Find the control handler in the request
1393  *
1394  * @req: The request
1395  * @parent: The parent control handler ('priv' in media_request_object_find())
1396  *
1397  * This function finds the control handler in the request. It may return
1398  * NULL if not found. When done, you must call v4l2_ctrl_request_hdl_put()
1399  * with the returned handler pointer.
1400  *
1401  * If the request is not in state VALIDATING or QUEUED, then this function
1402  * will always return NULL.
1403  *
1404  * Note that in state VALIDATING the req_queue_mutex is held, so
1405  * no objects can be added or deleted from the request.
1406  *
1407  * In state QUEUED it is the driver that will have to ensure this.
1408  */
1409 struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
1410 					struct v4l2_ctrl_handler *parent);
1411 
1412 /**
1413  * v4l2_ctrl_request_hdl_put - Put the control handler
1414  *
1415  * @hdl: Put this control handler
1416  *
1417  * This function released the control handler previously obtained from'
1418  * v4l2_ctrl_request_hdl_find().
1419  */
v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler * hdl)1420 static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
1421 {
1422 	if (hdl)
1423 		media_request_object_put(&hdl->req_obj);
1424 }
1425 
1426 /**
1427  * v4l2_ctrl_request_hdl_ctrl_find() - Find a control with the given ID.
1428  *
1429  * @hdl: The control handler from the request.
1430  * @id: The ID of the control to find.
1431  *
1432  * This function returns a pointer to the control if this control is
1433  * part of the request or NULL otherwise.
1434  */
1435 struct v4l2_ctrl *
1436 v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
1437 
1438 /* Helpers for ioctl_ops */
1439 
1440 /**
1441  * v4l2_queryctrl - Helper function to implement
1442  *	:ref:`VIDIOC_QUERYCTRL <vidioc_queryctrl>` ioctl
1443  *
1444  * @hdl: pointer to &struct v4l2_ctrl_handler
1445  * @qc: pointer to &struct v4l2_queryctrl
1446  *
1447  * If hdl == NULL then they will all return -EINVAL.
1448  */
1449 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
1450 
1451 /**
1452  * v4l2_query_ext_ctrl - Helper function to implement
1453  *	 :ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
1454  *
1455  * @hdl: pointer to &struct v4l2_ctrl_handler
1456  * @qc: pointer to &struct v4l2_query_ext_ctrl
1457  *
1458  * If hdl == NULL then they will all return -EINVAL.
1459  */
1460 int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl,
1461 			struct v4l2_query_ext_ctrl *qc);
1462 
1463 /**
1464  * v4l2_querymenu - Helper function to implement
1465  *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
1466  *
1467  * @hdl: pointer to &struct v4l2_ctrl_handler
1468  * @qm: pointer to &struct v4l2_querymenu
1469  *
1470  * If hdl == NULL then they will all return -EINVAL.
1471  */
1472 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
1473 
1474 /**
1475  * v4l2_g_ctrl - Helper function to implement
1476  *	:ref:`VIDIOC_G_CTRL <vidioc_g_ctrl>` ioctl
1477  *
1478  * @hdl: pointer to &struct v4l2_ctrl_handler
1479  * @ctrl: pointer to &struct v4l2_control
1480  *
1481  * If hdl == NULL then they will all return -EINVAL.
1482  */
1483 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
1484 
1485 /**
1486  * v4l2_s_ctrl - Helper function to implement
1487  *	:ref:`VIDIOC_S_CTRL <vidioc_g_ctrl>` ioctl
1488  *
1489  * @fh: pointer to &struct v4l2_fh
1490  * @hdl: pointer to &struct v4l2_ctrl_handler
1491  *
1492  * @ctrl: pointer to &struct v4l2_control
1493  *
1494  * If hdl == NULL then they will all return -EINVAL.
1495  */
1496 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1497 		struct v4l2_control *ctrl);
1498 
1499 /**
1500  * v4l2_g_ext_ctrls - Helper function to implement
1501  *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1502  *
1503  * @hdl: pointer to &struct v4l2_ctrl_handler
1504  * @vdev: pointer to &struct video_device
1505  * @mdev: pointer to &struct media_device
1506  * @c: pointer to &struct v4l2_ext_controls
1507  *
1508  * If hdl == NULL then they will all return -EINVAL.
1509  */
1510 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
1511 		     struct media_device *mdev, struct v4l2_ext_controls *c);
1512 
1513 /**
1514  * v4l2_try_ext_ctrls - Helper function to implement
1515  *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1516  *
1517  * @hdl: pointer to &struct v4l2_ctrl_handler
1518  * @vdev: pointer to &struct video_device
1519  * @mdev: pointer to &struct media_device
1520  * @c: pointer to &struct v4l2_ext_controls
1521  *
1522  * If hdl == NULL then they will all return -EINVAL.
1523  */
1524 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1525 		       struct video_device *vdev,
1526 		       struct media_device *mdev,
1527 		       struct v4l2_ext_controls *c);
1528 
1529 /**
1530  * v4l2_s_ext_ctrls - Helper function to implement
1531  *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
1532  *
1533  * @fh: pointer to &struct v4l2_fh
1534  * @hdl: pointer to &struct v4l2_ctrl_handler
1535  * @vdev: pointer to &struct video_device
1536  * @mdev: pointer to &struct media_device
1537  * @c: pointer to &struct v4l2_ext_controls
1538  *
1539  * If hdl == NULL then they will all return -EINVAL.
1540  */
1541 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1542 		     struct video_device *vdev,
1543 		     struct media_device *mdev,
1544 		     struct v4l2_ext_controls *c);
1545 
1546 /**
1547  * v4l2_ctrl_subdev_subscribe_event - Helper function to implement
1548  *	as a &struct v4l2_subdev_core_ops subscribe_event function
1549  *	that just subscribes control events.
1550  *
1551  * @sd: pointer to &struct v4l2_subdev
1552  * @fh: pointer to &struct v4l2_fh
1553  * @sub: pointer to &struct v4l2_event_subscription
1554  */
1555 int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
1556 				     struct v4l2_event_subscription *sub);
1557 
1558 /**
1559  * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control
1560  *	 handler.
1561  *
1562  * @sd: pointer to &struct v4l2_subdev
1563  */
1564 int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd);
1565 
1566 /**
1567  * v4l2_ctrl_new_fwnode_properties() - Register controls for the device
1568  *				       properties
1569  *
1570  * @hdl: pointer to &struct v4l2_ctrl_handler to register controls on
1571  * @ctrl_ops: pointer to &struct v4l2_ctrl_ops to register controls with
1572  * @p: pointer to &struct v4l2_fwnode_device_properties
1573  *
1574  * This function registers controls associated to device properties, using the
1575  * property values contained in @p parameter, if the property has been set to
1576  * a value.
1577  *
1578  * Currently the following v4l2 controls are parsed and registered:
1579  * - V4L2_CID_CAMERA_ORIENTATION
1580  * - V4L2_CID_CAMERA_SENSOR_ROTATION;
1581  *
1582  * Controls already registered by the caller with the @hdl control handler are
1583  * not overwritten. Callers should register the controls they want to handle
1584  * themselves before calling this function.
1585  *
1586  * Return: 0 on success, a negative error code on failure.
1587  */
1588 int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl,
1589 				    const struct v4l2_ctrl_ops *ctrl_ops,
1590 				    const struct v4l2_fwnode_device_properties *p);
1591 
1592 /**
1593  * v4l2_ctrl_type_op_equal - Default v4l2_ctrl_type_ops equal callback.
1594  *
1595  * @ctrl: The v4l2_ctrl pointer.
1596  * @ptr1: A v4l2 control value.
1597  * @ptr2: A v4l2 control value.
1598  *
1599  * Return: true if values are equal, otherwise false.
1600  */
1601 bool v4l2_ctrl_type_op_equal(const struct v4l2_ctrl *ctrl,
1602 			     union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
1603 
1604 /**
1605  * v4l2_ctrl_type_op_init - Default v4l2_ctrl_type_ops init callback.
1606  *
1607  * @ctrl: The v4l2_ctrl pointer.
1608  * @from_idx: Starting element index.
1609  * @ptr: The v4l2 control value.
1610  *
1611  * Return: void
1612  */
1613 void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
1614 			    union v4l2_ctrl_ptr ptr);
1615 
1616 /**
1617  * v4l2_ctrl_type_op_log - Default v4l2_ctrl_type_ops log callback.
1618  *
1619  * @ctrl: The v4l2_ctrl pointer.
1620  *
1621  * Return: void
1622  */
1623 void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
1624 
1625 /**
1626  * v4l2_ctrl_type_op_validate - Default v4l2_ctrl_type_ops validate callback.
1627  *
1628  * @ctrl: The v4l2_ctrl pointer.
1629  * @ptr: The v4l2 control value.
1630  *
1631  * Return: 0 on success, a negative error code on failure.
1632  */
1633 int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
1634 
1635 #endif
1636