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Hans Verkuil09965172010-08-01 14:32:42 -03001/*
2 V4L2 controls support header.
3
4 Copyright (C) 2010 Hans Verkuil <hverkuil@xs4all.nl>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#ifndef _V4L2_CTRLS_H
22#define _V4L2_CTRLS_H
23
24#include <linux/list.h>
Laurent Pinchart01c40c02010-11-19 11:20:06 -030025#include <linux/videodev2.h>
Hans Verkuil09965172010-08-01 14:32:42 -030026
27/* forward references */
Laurent Pinchart528f0f72012-04-23 08:20:35 -030028struct file;
Hans Verkuil09965172010-08-01 14:32:42 -030029struct v4l2_ctrl_handler;
Hans Verkuileb5b16e2011-06-14 10:04:06 -030030struct v4l2_ctrl_helper;
Hans Verkuil09965172010-08-01 14:32:42 -030031struct v4l2_ctrl;
32struct video_device;
33struct v4l2_subdev;
Hans Verkuil77068d32011-06-13 18:55:58 -030034struct v4l2_subscribed_event;
Hans Verkuil6e239392011-06-07 11:13:44 -030035struct v4l2_fh;
Hans Verkuila26243b2012-01-27 16:18:42 -030036struct poll_table_struct;
Hans Verkuil09965172010-08-01 14:32:42 -030037
38/** struct v4l2_ctrl_ops - The control operations that the driver has to provide.
39 * @g_volatile_ctrl: Get a new value for this control. Generally only relevant
40 * for volatile (and usually read-only) controls such as a control
41 * that returns the current signal strength which changes
42 * continuously.
43 * If not set, then the currently cached value will be returned.
44 * @try_ctrl: Test whether the control's value is valid. Only relevant when
45 * the usual min/max/step checks are not sufficient.
46 * @s_ctrl: Actually set the new control value. s_ctrl is compulsory. The
47 * ctrl->handler->lock is held when these ops are called, so no
48 * one else can access controls owned by that handler.
49 */
50struct v4l2_ctrl_ops {
51 int (*g_volatile_ctrl)(struct v4l2_ctrl *ctrl);
52 int (*try_ctrl)(struct v4l2_ctrl *ctrl);
53 int (*s_ctrl)(struct v4l2_ctrl *ctrl);
54};
55
56/** struct v4l2_ctrl - The control structure.
57 * @node: The list node.
Hans Verkuil77068d32011-06-13 18:55:58 -030058 * @ev_subs: The list of control event subscriptions.
Hans Verkuil09965172010-08-01 14:32:42 -030059 * @handler: The handler that owns the control.
60 * @cluster: Point to start of cluster array.
61 * @ncontrols: Number of controls in cluster array.
Hans Verkuil09965172010-08-01 14:32:42 -030062 * @done: Internal flag: set for each processed control.
Hans Verkuil2a863792011-01-11 14:45:03 -030063 * @is_new: Set when the user specified a new value for this control. It
64 * is also set when called from v4l2_ctrl_handler_setup. Drivers
65 * should never set this flag.
Hans Verkuil09965172010-08-01 14:32:42 -030066 * @is_private: If set, then this control is private to its handler and it
67 * will not be added to any other handlers. Drivers can set
68 * this flag.
Hans Verkuil72d877c2011-06-10 05:44:36 -030069 * @is_auto: If set, then this control selects whether the other cluster
70 * members are in 'automatic' mode or 'manual' mode. This is
71 * used for autogain/gain type clusters. Drivers should never
72 * set this flag directly.
Hans Verkuil5626b8c2011-08-26 07:53:53 -030073 * @has_volatiles: If set, then one or more members of the cluster are volatile.
74 * Drivers should never touch this flag.
Hans Verkuil72d877c2011-06-10 05:44:36 -030075 * @manual_mode_value: If the is_auto flag is set, then this is the value
76 * of the auto control that determines if that control is in
77 * manual mode. So if the value of the auto control equals this
78 * value, then the whole cluster is in manual mode. Drivers should
79 * never set this flag directly.
Hans Verkuil09965172010-08-01 14:32:42 -030080 * @ops: The control ops.
81 * @id: The control ID.
82 * @name: The control name.
83 * @type: The control type.
84 * @minimum: The control's minimum value.
85 * @maximum: The control's maximum value.
86 * @default_value: The control's default value.
87 * @step: The control's step value for non-menu controls.
88 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
89 * easy to skip menu items that are not valid. If bit X is set,
90 * then menu item X is skipped. Of course, this only works for
91 * menus with <= 32 menu items. There are no menus that come
92 * close to that number, so this is OK. Should we ever need more,
93 * then this will have to be extended to a u64 or a bit array.
94 * @qmenu: A const char * array for all menu items. Array entries that are
95 * empty strings ("") correspond to non-existing menu items (this
96 * is in addition to the menu_skip_mask above). The last entry
97 * must be NULL.
98 * @flags: The control's flags.
99 * @cur: The control's current value.
100 * @val: The control's new s32 value.
101 * @val64: The control's new s64 value.
102 * @string: The control's new string value.
103 * @priv: The control's private pointer. For use by the driver. It is
104 * untouched by the control framework. Note that this pointer is
105 * not freed when the control is deleted. Should this be needed
106 * then a new internal bitfield can be added to tell the framework
107 * to free this pointer.
108 */
109struct v4l2_ctrl {
110 /* Administrative fields */
111 struct list_head node;
Hans Verkuil77068d32011-06-13 18:55:58 -0300112 struct list_head ev_subs;
Hans Verkuil09965172010-08-01 14:32:42 -0300113 struct v4l2_ctrl_handler *handler;
114 struct v4l2_ctrl **cluster;
115 unsigned ncontrols;
Hans Verkuil09965172010-08-01 14:32:42 -0300116 unsigned int done:1;
117
Hans Verkuil2a863792011-01-11 14:45:03 -0300118 unsigned int is_new:1;
Hans Verkuil09965172010-08-01 14:32:42 -0300119 unsigned int is_private:1;
Hans Verkuil72d877c2011-06-10 05:44:36 -0300120 unsigned int is_auto:1;
Hans Verkuil5626b8c2011-08-26 07:53:53 -0300121 unsigned int has_volatiles:1;
Hans Verkuil82a7c042011-06-28 10:43:13 -0300122 unsigned int manual_mode_value:8;
Hans Verkuil09965172010-08-01 14:32:42 -0300123
124 const struct v4l2_ctrl_ops *ops;
125 u32 id;
126 const char *name;
127 enum v4l2_ctrl_type type;
128 s32 minimum, maximum, default_value;
129 union {
130 u32 step;
131 u32 menu_skip_mask;
132 };
Sakari Ailusce580fe2011-08-04 13:51:11 -0300133 union {
134 const char * const *qmenu;
135 const s64 *qmenu_int;
136 };
Hans Verkuil09965172010-08-01 14:32:42 -0300137 unsigned long flags;
138 union {
139 s32 val;
140 s64 val64;
141 char *string;
142 } cur;
143 union {
144 s32 val;
145 s64 val64;
146 char *string;
147 };
148 void *priv;
149};
150
151/** struct v4l2_ctrl_ref - The control reference.
152 * @node: List node for the sorted list.
153 * @next: Single-link list node for the hash.
154 * @ctrl: The actual control information.
Hans Verkuileb5b16e2011-06-14 10:04:06 -0300155 * @helper: Pointer to helper struct. Used internally in prepare_ext_ctrls().
Hans Verkuil09965172010-08-01 14:32:42 -0300156 *
157 * Each control handler has a list of these refs. The list_head is used to
158 * keep a sorted-by-control-ID list of all controls, while the next pointer
159 * is used to link the control in the hash's bucket.
160 */
161struct v4l2_ctrl_ref {
162 struct list_head node;
163 struct v4l2_ctrl_ref *next;
164 struct v4l2_ctrl *ctrl;
Hans Verkuileb5b16e2011-06-14 10:04:06 -0300165 struct v4l2_ctrl_helper *helper;
Hans Verkuil09965172010-08-01 14:32:42 -0300166};
167
168/** struct v4l2_ctrl_handler - The control handler keeps track of all the
169 * controls: both the controls owned by the handler and those inherited
170 * from other handlers.
Sakari Ailus77e7c4e2012-01-24 21:05:34 -0300171 * @_lock: Default for "lock".
Hans Verkuil09965172010-08-01 14:32:42 -0300172 * @lock: Lock to control access to this handler and its controls.
Sakari Ailus77e7c4e2012-01-24 21:05:34 -0300173 * May be replaced by the user right after init.
Hans Verkuil09965172010-08-01 14:32:42 -0300174 * @ctrls: The list of controls owned by this handler.
175 * @ctrl_refs: The list of control references.
176 * @cached: The last found control reference. It is common that the same
177 * control is needed multiple times, so this is a simple
178 * optimization.
179 * @buckets: Buckets for the hashing. Allows for quick control lookup.
180 * @nr_of_buckets: Total number of buckets in the array.
181 * @error: The error code of the first failed control addition.
182 */
183struct v4l2_ctrl_handler {
Sakari Ailus77e7c4e2012-01-24 21:05:34 -0300184 struct mutex _lock;
185 struct mutex *lock;
Hans Verkuil09965172010-08-01 14:32:42 -0300186 struct list_head ctrls;
187 struct list_head ctrl_refs;
188 struct v4l2_ctrl_ref *cached;
189 struct v4l2_ctrl_ref **buckets;
190 u16 nr_of_buckets;
191 int error;
192};
193
194/** struct v4l2_ctrl_config - Control configuration structure.
195 * @ops: The control ops.
196 * @id: The control ID.
197 * @name: The control name.
198 * @type: The control type.
199 * @min: The control's minimum value.
200 * @max: The control's maximum value.
201 * @step: The control's step value for non-menu controls.
202 * @def: The control's default value.
203 * @flags: The control's flags.
204 * @menu_skip_mask: The control's skip mask for menu controls. This makes it
205 * easy to skip menu items that are not valid. If bit X is set,
206 * then menu item X is skipped. Of course, this only works for
207 * menus with <= 32 menu items. There are no menus that come
208 * close to that number, so this is OK. Should we ever need more,
209 * then this will have to be extended to a u64 or a bit array.
210 * @qmenu: A const char * array for all menu items. Array entries that are
211 * empty strings ("") correspond to non-existing menu items (this
212 * is in addition to the menu_skip_mask above). The last entry
213 * must be NULL.
214 * @is_private: If set, then this control is private to its handler and it
215 * will not be added to any other handlers.
Hans Verkuil09965172010-08-01 14:32:42 -0300216 */
217struct v4l2_ctrl_config {
218 const struct v4l2_ctrl_ops *ops;
219 u32 id;
220 const char *name;
221 enum v4l2_ctrl_type type;
222 s32 min;
223 s32 max;
224 u32 step;
225 s32 def;
226 u32 flags;
227 u32 menu_skip_mask;
Hans Verkuil513521e2010-12-29 14:25:52 -0300228 const char * const *qmenu;
Sakari Ailusce580fe2011-08-04 13:51:11 -0300229 const s64 *qmenu_int;
Hans Verkuil09965172010-08-01 14:32:42 -0300230 unsigned int is_private:1;
Hans Verkuil09965172010-08-01 14:32:42 -0300231};
232
233/** v4l2_ctrl_fill() - Fill in the control fields based on the control ID.
234 *
235 * This works for all standard V4L2 controls.
236 * For non-standard controls it will only fill in the given arguments
237 * and @name will be NULL.
238 *
239 * This function will overwrite the contents of @name, @type and @flags.
240 * The contents of @min, @max, @step and @def may be modified depending on
241 * the type.
242 *
243 * Do not use in drivers! It is used internally for backwards compatibility
244 * control handling only. Once all drivers are converted to use the new
245 * control framework this function will no longer be exported.
246 */
247void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
248 s32 *min, s32 *max, s32 *step, s32 *def, u32 *flags);
249
250
251/** v4l2_ctrl_handler_init() - Initialize the control handler.
252 * @hdl: The control handler.
253 * @nr_of_controls_hint: A hint of how many controls this handler is
254 * expected to refer to. This is the total number, so including
255 * any inherited controls. It doesn't have to be precise, but if
256 * it is way off, then you either waste memory (too many buckets
257 * are allocated) or the control lookup becomes slower (not enough
258 * buckets are allocated, so there are more slow list lookups).
259 * It will always work, though.
260 *
261 * Returns an error if the buckets could not be allocated. This error will
262 * also be stored in @hdl->error.
263 */
264int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler *hdl,
265 unsigned nr_of_controls_hint);
266
267/** v4l2_ctrl_handler_free() - Free all controls owned by the handler and free
268 * the control list.
269 * @hdl: The control handler.
270 *
271 * Does nothing if @hdl == NULL.
272 */
273void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl);
274
275/** v4l2_ctrl_handler_setup() - Call the s_ctrl op for all controls belonging
276 * to the handler to initialize the hardware to the current control values.
277 * @hdl: The control handler.
278 *
279 * Button controls will be skipped, as are read-only controls.
280 *
281 * If @hdl == NULL, then this just returns 0.
282 */
283int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl);
284
285/** v4l2_ctrl_handler_log_status() - Log all controls owned by the handler.
286 * @hdl: The control handler.
287 * @prefix: The prefix to use when logging the control values. If the
288 * prefix does not end with a space, then ": " will be added
289 * after the prefix. If @prefix == NULL, then no prefix will be
290 * used.
291 *
292 * For use with VIDIOC_LOG_STATUS.
293 *
294 * Does nothing if @hdl == NULL.
295 */
296void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
297 const char *prefix);
298
299/** v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2
300 * control.
301 * @hdl: The control handler.
302 * @cfg: The control's configuration data.
303 * @priv: The control's driver-specific private data.
304 *
305 * If the &v4l2_ctrl struct could not be allocated then NULL is returned
306 * and @hdl->error is set to the error code (if it wasn't set already).
307 */
308struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
309 const struct v4l2_ctrl_config *cfg, void *priv);
310
311/** v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu control.
312 * @hdl: The control handler.
313 * @ops: The control ops.
314 * @id: The control ID.
315 * @min: The control's minimum value.
316 * @max: The control's maximum value.
317 * @step: The control's step value
318 * @def: The control's default value.
319 *
320 * If the &v4l2_ctrl struct could not be allocated, or the control
321 * ID is not known, then NULL is returned and @hdl->error is set to the
322 * appropriate error code (if it wasn't set already).
323 *
324 * If @id refers to a menu control, then this function will return NULL.
325 *
326 * Use v4l2_ctrl_new_std_menu() when adding menu controls.
327 */
328struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
329 const struct v4l2_ctrl_ops *ops,
330 u32 id, s32 min, s32 max, u32 step, s32 def);
331
332/** v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 menu control.
333 * @hdl: The control handler.
334 * @ops: The control ops.
335 * @id: The control ID.
336 * @max: The control's maximum value.
337 * @mask: The control's skip mask for menu controls. This makes it
338 * easy to skip menu items that are not valid. If bit X is set,
339 * then menu item X is skipped. Of course, this only works for
340 * menus with <= 32 menu items. There are no menus that come
341 * close to that number, so this is OK. Should we ever need more,
342 * then this will have to be extended to a u64 or a bit array.
343 * @def: The control's default value.
344 *
345 * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value
346 * determines which menu items are to be skipped.
347 *
348 * If @id refers to a non-menu control, then this function will return NULL.
349 */
350struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
351 const struct v4l2_ctrl_ops *ops,
352 u32 id, s32 max, s32 mask, s32 def);
353
Sylwester Nawrocki515f3282012-05-06 15:30:44 -0300354/** v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
355 * @hdl: The control handler.
356 * @ops: The control ops.
357 * @id: The control ID.
358 * @max: The control's maximum value.
359 * @def: The control's default value.
360 * @qmenu_int: The control's menu entries.
361 *
362 * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly
363 * takes as an argument an array of integers determining the menu items.
364 *
365 * If @id refers to a non-integer-menu control, then this function will return NULL.
366 */
367struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
368 const struct v4l2_ctrl_ops *ops,
369 u32 id, s32 max, s32 def, const s64 *qmenu_int);
370
Hans Verkuil09965172010-08-01 14:32:42 -0300371/** v4l2_ctrl_add_ctrl() - Add a control from another handler to this handler.
372 * @hdl: The control handler.
373 * @ctrl: The control to add.
374 *
375 * It will return NULL if it was unable to add the control reference.
376 * If the control already belonged to the handler, then it will do
377 * nothing and just return @ctrl.
378 */
379struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl,
380 struct v4l2_ctrl *ctrl);
381
382/** v4l2_ctrl_add_handler() - Add all controls from handler @add to
383 * handler @hdl.
384 * @hdl: The control handler.
385 * @add: The control handler whose controls you want to add to
386 * the @hdl control handler.
387 *
388 * Does nothing if either of the two is a NULL pointer.
389 * In case of an error @hdl->error will be set to the error code (if it
390 * wasn't set already).
391 */
392int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
393 struct v4l2_ctrl_handler *add);
394
395
396/** v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging to that cluster.
397 * @ncontrols: The number of controls in this cluster.
398 * @controls: The cluster control array of size @ncontrols.
399 */
400void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls);
401
402
Hans Verkuil72d877c2011-06-10 05:44:36 -0300403/** v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging to
404 * that cluster and set it up for autofoo/foo-type handling.
405 * @ncontrols: The number of controls in this cluster.
406 * @controls: The cluster control array of size @ncontrols. The first control
407 * must be the 'auto' control (e.g. autogain, autoexposure, etc.)
408 * @manual_val: The value for the first control in the cluster that equals the
409 * manual setting.
410 * @set_volatile: If true, then all controls except the first auto control will
Hans Verkuil88365102011-08-26 07:35:14 -0300411 * be volatile.
Hans Verkuil72d877c2011-06-10 05:44:36 -0300412 *
413 * Use for control groups where one control selects some automatic feature and
414 * the other controls are only active whenever the automatic feature is turned
415 * off (manual mode). Typical examples: autogain vs gain, auto-whitebalance vs
416 * red and blue balance, etc.
417 *
418 * The behavior of such controls is as follows:
419 *
420 * When the autofoo control is set to automatic, then any manual controls
421 * are set to inactive and any reads will call g_volatile_ctrl (if the control
422 * was marked volatile).
423 *
424 * When the autofoo control is set to manual, then any manual controls will
425 * be marked active, and any reads will just return the current value without
426 * going through g_volatile_ctrl.
427 *
428 * In addition, this function will set the V4L2_CTRL_FLAG_UPDATE flag
429 * on the autofoo control and V4L2_CTRL_FLAG_INACTIVE on the foo control(s)
430 * if autofoo is in auto mode.
431 */
432void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls,
433 u8 manual_val, bool set_volatile);
434
435
Hans Verkuil09965172010-08-01 14:32:42 -0300436/** v4l2_ctrl_find() - Find a control with the given ID.
437 * @hdl: The control handler.
438 * @id: The control ID to find.
439 *
440 * If @hdl == NULL this will return NULL as well. Will lock the handler so
441 * do not use from inside &v4l2_ctrl_ops.
442 */
443struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);
444
445/** v4l2_ctrl_activate() - Make the control active or inactive.
446 * @ctrl: The control to (de)activate.
447 * @active: True if the control should become active.
448 *
449 * This sets or clears the V4L2_CTRL_FLAG_INACTIVE flag atomically.
450 * Does nothing if @ctrl == NULL.
451 * This will usually be called from within the s_ctrl op.
Hans Verkuil6e239392011-06-07 11:13:44 -0300452 * The V4L2_EVENT_CTRL event will be generated afterwards.
Hans Verkuil09965172010-08-01 14:32:42 -0300453 *
Hans Verkuil6e239392011-06-07 11:13:44 -0300454 * This function assumes that the control handler is locked.
Hans Verkuil09965172010-08-01 14:32:42 -0300455 */
456void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);
457
458/** v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.
459 * @ctrl: The control to (de)activate.
460 * @grabbed: True if the control should become grabbed.
461 *
462 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.
463 * Does nothing if @ctrl == NULL.
Hans Verkuil6e239392011-06-07 11:13:44 -0300464 * The V4L2_EVENT_CTRL event will be generated afterwards.
Hans Verkuil09965172010-08-01 14:32:42 -0300465 * This will usually be called when starting or stopping streaming in the
466 * driver.
467 *
Hans Verkuil6e239392011-06-07 11:13:44 -0300468 * This function assumes that the control handler is not locked and will
469 * take the lock itself.
Hans Verkuil09965172010-08-01 14:32:42 -0300470 */
471void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);
472
473/** v4l2_ctrl_lock() - Helper function to lock the handler
474 * associated with the control.
475 * @ctrl: The control to lock.
476 */
477static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl)
478{
Sakari Ailus77e7c4e2012-01-24 21:05:34 -0300479 mutex_lock(ctrl->handler->lock);
Hans Verkuil09965172010-08-01 14:32:42 -0300480}
481
482/** v4l2_ctrl_lock() - Helper function to unlock the handler
483 * associated with the control.
484 * @ctrl: The control to unlock.
485 */
486static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl)
487{
Sakari Ailus77e7c4e2012-01-24 21:05:34 -0300488 mutex_unlock(ctrl->handler->lock);
Hans Verkuil09965172010-08-01 14:32:42 -0300489}
490
491/** v4l2_ctrl_g_ctrl() - Helper function to get the control's value from within a driver.
492 * @ctrl: The control.
493 *
494 * This returns the control's value safely by going through the control
495 * framework. This function will lock the control's handler, so it cannot be
496 * used from within the &v4l2_ctrl_ops functions.
497 *
498 * This function is for integer type controls only.
499 */
500s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
501
502/** v4l2_ctrl_s_ctrl() - Helper function to set the control's value from within a driver.
503 * @ctrl: The control.
504 * @val: The new value.
505 *
506 * This set the control's new value safely by going through the control
507 * framework. This function will lock the control's handler, so it cannot be
508 * used from within the &v4l2_ctrl_ops functions.
509 *
510 * This function is for integer type controls only.
511 */
512int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
513
Hans Verkuilce727572011-06-10 05:56:39 -0300514/* Internal helper functions that deal with control events. */
Hans de Goede3e3661492012-04-08 12:59:47 -0300515extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
516void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new);
517void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new);
Hans Verkuil6e239392011-06-07 11:13:44 -0300518
Hans Verkuile2ecb252012-02-02 08:20:53 -0300519/* Can be used as a vidioc_log_status function that just dumps all controls
520 associated with the filehandle. */
521int v4l2_ctrl_log_status(struct file *file, void *fh);
522
Hans Verkuila26243b2012-01-27 16:18:42 -0300523/* Can be used as a vidioc_subscribe_event function that just subscribes
524 control events. */
525int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
526 struct v4l2_event_subscription *sub);
527
528/* Can be used as a poll function that just polls for control events. */
529unsigned int v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
530
Hans Verkuil09965172010-08-01 14:32:42 -0300531/* Helpers for ioctl_ops. If hdl == NULL then they will all return -EINVAL. */
532int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
533int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm);
534int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl);
Hans Verkuilab892ba2011-06-07 06:47:18 -0300535int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
536 struct v4l2_control *ctrl);
Hans Verkuil09965172010-08-01 14:32:42 -0300537int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c);
538int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c);
Hans Verkuilab892ba2011-06-07 06:47:18 -0300539int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
540 struct v4l2_ext_controls *c);
Hans Verkuil09965172010-08-01 14:32:42 -0300541
542/* Helpers for subdevices. If the associated ctrl_handler == NULL then they
543 will all return -EINVAL. */
544int v4l2_subdev_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc);
545int v4l2_subdev_querymenu(struct v4l2_subdev *sd, struct v4l2_querymenu *qm);
546int v4l2_subdev_g_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs);
547int v4l2_subdev_try_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs);
548int v4l2_subdev_s_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs);
549int v4l2_subdev_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
550int v4l2_subdev_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
551
552#endif