From 8ec4bee7c10e55ca9df398a28cbd53beb26b343c Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 22 Jul 2016 13:57:29 -0300 Subject: [PATCH] [media] v4l2-ctrls.h: fully document the header file There are lots of undocumented stuff on this header. Document them. Signed-off-by: Mauro Carvalho Chehab --- include/media/v4l2-ctrls.h | 365 ++++++++++++++++++++++++++++--------- 1 file changed, 279 insertions(+), 86 deletions(-) diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h index d6f63406b885..178a88d45aea 100644 --- a/include/media/v4l2-ctrls.h +++ b/include/media/v4l2-ctrls.h @@ -1,21 +1,17 @@ /* - V4L2 controls support header. - - Copyright (C) 2010 Hans Verkuil - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * V4L2 controls support header. + * + * Copyright (C) 2010 Hans Verkuil + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. */ #ifndef _V4L2_CTRLS_H @@ -58,6 +54,7 @@ union v4l2_ctrl_ptr { /** * struct v4l2_ctrl_ops - The control operations that the driver has to provide. + * * @g_volatile_ctrl: Get a new value for this control. Generally only relevant * for volatile (and usually read-only) controls such as a control * that returns the current signal strength which changes @@ -77,12 +74,13 @@ struct v4l2_ctrl_ops { /** * struct v4l2_ctrl_type_ops - The control type operations that the driver - * has to provide. + * has to provide. * * @equal: return true if both values are equal. * @init: initialize the value. * @log: log the value. - * @validate: validate the value. Return 0 on success and a negative value otherwise. + * @validate: validate the value. Return 0 on success and a negative value + * otherwise. */ struct v4l2_ctrl_type_ops { bool (*equal)(const struct v4l2_ctrl *ctrl, u32 idx, @@ -99,6 +97,7 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); /** * struct v4l2_ctrl - The control structure. + * * @node: The list node. * @ev_subs: The list of control event subscriptions. * @handler: The handler that owns the control. @@ -106,7 +105,7 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); * @ncontrols: Number of controls in cluster array. * @done: Internal flag: set for each processed control. * @is_new: Set when the user specified a new value for this control. It - * is also set when called from v4l2_ctrl_handler_setup. Drivers + * is also set when called from v4l2_ctrl_handler_setup(). Drivers * should never set this flag. * @has_changed: Set when the current value differs from the new value. Drivers * should never use this flag. @@ -119,9 +118,10 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); * set this flag directly. * @is_int: If set, then this control has a simple integer value (i.e. it * uses ctrl->val). - * @is_string: If set, then this control has type V4L2_CTRL_TYPE_STRING. - * @is_ptr: If set, then this control is an array and/or has type >= V4L2_CTRL_COMPOUND_TYPES - * and/or has type V4L2_CTRL_TYPE_STRING. In other words, struct + * @is_string: If set, then this control has type %V4L2_CTRL_TYPE_STRING. + * @is_ptr: If set, then this control is an array and/or has type >= + * %V4L2_CTRL_COMPOUND_TYPES + * and/or has type %V4L2_CTRL_TYPE_STRING. In other words, &struct * v4l2_ext_control uses field p to point to the data. * @is_array: If set, then this control contains an N-dimensional array. * @has_volatiles: If set, then one or more members of the cluster are volatile. @@ -177,7 +177,8 @@ struct v4l2_ctrl { struct list_head ev_subs; struct v4l2_ctrl_handler *handler; struct v4l2_ctrl **cluster; - unsigned ncontrols; + unsigned int ncontrols; + unsigned int done:1; unsigned int is_new:1; @@ -223,10 +224,12 @@ struct v4l2_ctrl { /** * struct v4l2_ctrl_ref - The control reference. + * * @node: List node for the sorted list. * @next: Single-link list node for the hash. * @ctrl: The actual control information. - * @helper: Pointer to helper struct. Used internally in prepare_ext_ctrls(). + * @helper: Pointer to helper struct. Used internally in + * prepare_ext_ctrls(). * * Each control handler has a list of these refs. The list_head is used to * keep a sorted-by-control-ID list of all controls, while the next pointer @@ -241,8 +244,9 @@ struct v4l2_ctrl_ref { /** * struct v4l2_ctrl_handler - The control handler keeps track of all the - * controls: both the controls owned by the handler and those inherited - * from other handlers. + * controls: both the controls owned by the handler and those inherited + * from other handlers. + * * @_lock: Default for "lock". * @lock: Lock to control access to this handler and its controls. * May be replaced by the user right after init. @@ -252,7 +256,8 @@ struct v4l2_ctrl_ref { * control is needed multiple times, so this is a simple * optimization. * @buckets: Buckets for the hashing. Allows for quick control lookup. - * @notify: A notify callback that is called whenever the control changes value. + * @notify: A notify callback that is called whenever the control changes + * value. * Note that the handler's lock is held when the notify function * is called! * @notify_priv: Passed as argument to the v4l2_ctrl notify callback. @@ -274,6 +279,7 @@ struct v4l2_ctrl_handler { /** * struct v4l2_ctrl_config - Control configuration structure. + * * @ops: The control ops. * @type_ops: The control type ops. Only needed for compound controls. * @id: The control ID. @@ -282,7 +288,7 @@ struct v4l2_ctrl_handler { * @min: The control's minimum value. * @max: The control's maximum value. * @step: The control's step value for non-menu controls. - * @def: The control's default value. + * @def: The control's default value. * @dims: The size of each dimension. * @elem_size: The size in bytes of the control. * @flags: The control's flags. @@ -297,7 +303,7 @@ struct v4l2_ctrl_handler { * is in addition to the menu_skip_mask above). The last entry * must be NULL. * @qmenu_int: A const s64 integer array for all menu items of the type - * V4L2_CTRL_TYPE_INTEGER_MENU. + * V4L2_CTRL_TYPE_INTEGER_MENU. * @is_private: If set, then this control is private to its handler and it * will not be added to any other handlers. */ @@ -320,20 +326,31 @@ struct v4l2_ctrl_config { unsigned int is_private:1; }; -/* - * v4l2_ctrl_fill() - Fill in the control fields based on the control ID. +/** + * v4l2_ctrl_fill - Fill in the control fields based on the control ID. + * + * @id: ID of the control + * @name: name of the control + * @type: type of the control + * @min: minimum value for the control + * @max: maximum value for the control + * @step: control step + * @def: default value for the control + * @flags: flags to be used on the control * * This works for all standard V4L2 controls. * For non-standard controls it will only fill in the given arguments - * and @name will be NULL. + * and @name will be %NULL. * * This function will overwrite the contents of @name, @type and @flags. * The contents of @min, @max, @step and @def may be modified depending on * the type. * - * Do not use in drivers! It is used internally for backwards compatibility - * control handling only. Once all drivers are converted to use the new - * control framework this function will no longer be exported. + * .. note:: + * + * Do not use in drivers! It is used internally for backwards compatibility + * control handling only. Once all drivers are converted to use the new + * control framework this function will no longer be exported. */ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, s64 *min, s64 *max, u64 *step, s64 *def, u32 *flags); @@ -359,7 +376,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, * macro that hides the @key and @name arguments. */ int v4l2_ctrl_handler_init_class(struct v4l2_ctrl_handler *hdl, - unsigned nr_of_controls_hint, + unsigned int nr_of_controls_hint, struct lock_class_key *key, const char *name); #ifdef CONFIG_LOCKDEP @@ -436,7 +453,8 @@ void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, /** * v4l2_ctrl_new_custom() - Allocate and initialize a new custom V4L2 - * control. + * control. + * * @hdl: The control handler. * @cfg: The control's configuration data. * @priv: The control's driver-specific private data. @@ -445,17 +463,20 @@ void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, * and @hdl->error is set to the error code (if it wasn't set already). */ struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, - const struct v4l2_ctrl_config *cfg, void *priv); + const struct v4l2_ctrl_config *cfg, + void *priv); /** - * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu control. + * v4l2_ctrl_new_std() - Allocate and initialize a new standard V4L2 non-menu + * control. + * * @hdl: The control handler. * @ops: The control ops. - * @id: The control ID. + * @id: The control ID. * @min: The control's minimum value. * @max: The control's maximum value. * @step: The control's step value - * @def: The control's default value. + * @def: The control's default value. * * If the &v4l2_ctrl struct could not be allocated, or the control * ID is not known, then NULL is returned and @hdl->error is set to the @@ -466,22 +487,25 @@ struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl, * Use v4l2_ctrl_new_std_menu() when adding menu controls. */ struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, - const struct v4l2_ctrl_ops *ops, - u32 id, s64 min, s64 max, u64 step, s64 def); + const struct v4l2_ctrl_ops *ops, + u32 id, s64 min, s64 max, u64 step, + s64 def); /** - * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 menu control. + * v4l2_ctrl_new_std_menu() - Allocate and initialize a new standard V4L2 + * menu control. + * * @hdl: The control handler. * @ops: The control ops. - * @id: The control ID. + * @id: The control ID. * @max: The control's maximum value. - * @mask: The control's skip mask for menu controls. This makes it + * @mask: The control's skip mask for menu controls. This makes it * easy to skip menu items that are not valid. If bit X is set, * then menu item X is skipped. Of course, this only works for * menus with <= 64 menu items. There are no menus that come * close to that number, so this is OK. Should we ever need more, * then this will have to be extended to a bit array. - * @def: The control's default value. + * @def: The control's default value. * * Same as v4l2_ctrl_new_std(), but @min is set to 0 and the @mask value * determines which menu items are to be skipped. @@ -489,12 +513,13 @@ struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl, * If @id refers to a non-menu control, then this function will return NULL. */ struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, - const struct v4l2_ctrl_ops *ops, - u32 id, u8 max, u64 mask, u8 def); + const struct v4l2_ctrl_ops *ops, + u32 id, u8 max, u64 mask, u8 def); /** * v4l2_ctrl_new_std_menu_items() - Create a new standard V4L2 menu control - * with driver specific menu. + * with driver specific menu. + * * @hdl: The control handler. * @ops: The control ops. * @id: The control ID. @@ -513,11 +538,14 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl, * */ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, - const struct v4l2_ctrl_ops *ops, u32 id, u8 max, - u64 mask, u8 def, const char * const *qmenu); + const struct v4l2_ctrl_ops *ops, + u32 id, u8 max, + u64 mask, u8 def, + const char * const *qmenu); /** * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control. + * * @hdl: The control handler. * @ops: The control ops. * @id: The control ID. @@ -528,17 +556,20 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl, * Same as v4l2_ctrl_new_std_menu(), but @mask is set to 0 and it additionaly * takes as an argument an array of integers determining the menu items. * - * If @id refers to a non-integer-menu control, then this function will return NULL. + * If @id refers to a non-integer-menu control, then this function will + * return %NULL. */ struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl, - const struct v4l2_ctrl_ops *ops, - u32 id, u8 max, u8 def, const s64 *qmenu_int); + const struct v4l2_ctrl_ops *ops, + u32 id, u8 max, u8 def, + const s64 *qmenu_int); typedef bool (*v4l2_ctrl_filter)(const struct v4l2_ctrl *ctrl); /** * v4l2_ctrl_add_handler() - Add all controls from handler @add to - * handler @hdl. + * handler @hdl. + * * @hdl: The control handler. * @add: The control handler whose controls you want to add to * the @hdl control handler. @@ -556,6 +587,7 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, /** * v4l2_ctrl_radio_filter() - Standard filter for radio controls. + * * @ctrl: The control that is filtered. * * This will return true for any controls that are valid for radio device @@ -567,16 +599,19 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl); /** - * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging to that cluster. + * v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging + * to that cluster. + * * @ncontrols: The number of controls in this cluster. - * @controls: The cluster control array of size @ncontrols. + * @controls: The cluster control array of size @ncontrols. */ -void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls); +void v4l2_ctrl_cluster(unsigned int ncontrols, struct v4l2_ctrl **controls); /** - * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging to - * that cluster and set it up for autofoo/foo-type handling. + * v4l2_ctrl_auto_cluster() - Mark all controls in the cluster as belonging + * to that cluster and set it up for autofoo/foo-type handling. + * * @ncontrols: The number of controls in this cluster. * @controls: The cluster control array of size @ncontrols. The first control * must be the 'auto' control (e.g. autogain, autoexposure, etc.) @@ -604,12 +639,14 @@ void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls); * on the autofoo control and V4L2_CTRL_FLAG_INACTIVE on the foo control(s) * if autofoo is in auto mode. */ -void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls, - u8 manual_val, bool set_volatile); +void v4l2_ctrl_auto_cluster(unsigned int ncontrols, + struct v4l2_ctrl **controls, + u8 manual_val, bool set_volatile); /** * v4l2_ctrl_find() - Find a control with the given ID. + * * @hdl: The control handler. * @id: The control ID to find. * @@ -634,6 +671,7 @@ void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); /** * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed. + * * @ctrl: The control to (de)activate. * @grabbed: True if the control should become grabbed. * @@ -673,6 +711,7 @@ int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, /** * v4l2_ctrl_modify_range() - Update the range of a control. + * * @ctrl: The control to update. * @min: The control's minimum value. * @max: The control's maximum value. @@ -703,6 +742,7 @@ static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, /** * v4l2_ctrl_notify() - Function to set a notify callback for a control. + * * @ctrl: The control. * @notify: The callback function. * @priv: The callback private handle, passed as argument to the callback. @@ -714,10 +754,12 @@ static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, * There can be only one notify. If another already exists, then a WARN_ON * will be issued and the function will do nothing. */ -void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, void *priv); +void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, + void *priv); /** * v4l2_ctrl_get_name() - Get the name of the control + * * @id: The control ID. * * This function returns the name of the given control ID or NULL if it isn't @@ -727,6 +769,7 @@ const char *v4l2_ctrl_get_name(u32 id); /** * v4l2_ctrl_get_menu() - Get the menu string array of the control + * * @id: The control ID. * * This function returns the NULL-terminated menu string array name of the @@ -736,6 +779,7 @@ const char * const *v4l2_ctrl_get_menu(u32 id); /** * v4l2_ctrl_get_int_menu() - Get the integer menu array of the control + * * @id: The control ID. * @len: The size of the integer array. * @@ -745,7 +789,9 @@ const char * const *v4l2_ctrl_get_menu(u32 id); const s64 *v4l2_ctrl_get_int_menu(u32 id, u32 *len); /** - * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from within a driver. + * v4l2_ctrl_g_ctrl() - Helper function to get the control's value from + * within a driver. + * * @ctrl: The control. * * This returns the control's value safely by going through the control @@ -758,8 +804,9 @@ s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); /** * __v4l2_ctrl_s_ctrl() - Unlocked variant of v4l2_ctrl_s_ctrl(). + * * @ctrl: The control. - * @val: The new value. + * @val: TheControls name new value. * * This sets the control's new value safely by going through the control * framework. This function assumes the control's handler is already locked, @@ -769,7 +816,9 @@ s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl); */ int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val); -/** v4l2_ctrl_s_ctrl() - Helper function to set the control's value from within a driver. +/** + * v4l2_ctrl_s_ctrl() - Helper function to set the control's value from + * within a driver. * @ctrl: The control. * @val: The new value. * @@ -793,6 +842,7 @@ static inline int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) /** * v4l2_ctrl_g_ctrl_int64() - Helper function to get a 64-bit control's value * from within a driver. + * * @ctrl: The control. * * This returns the control's value safely by going through the control @@ -817,7 +867,8 @@ s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl); */ int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val); -/** v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value +/** + * v4l2_ctrl_s_ctrl_int64() - Helper function to set a 64-bit control's value * from within a driver. * * @ctrl: The control. @@ -840,7 +891,8 @@ static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) return rval; } -/** __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). +/** + * __v4l2_ctrl_s_ctrl_string() - Unlocked variant of v4l2_ctrl_s_ctrl_string(). * * @ctrl: The control. * @s: The new string. @@ -853,12 +905,13 @@ static inline int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) */ int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s); -/** v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value +/** + * v4l2_ctrl_s_ctrl_string() - Helper function to set a control's string value * from within a driver. * * @ctrl: The control. * @s: The new string. - * + *Controls name * This sets the control's new string safely by going through the control * framework. This function will lock the control's handler, so it cannot be * used from within the &v4l2_ctrl_ops functions. @@ -878,39 +931,179 @@ static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s) /* Internal helper functions that deal with control events. */ extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops; + +/** + * v4l2_ctrl_replace - Function to be used as a callback to + * &struct v4l2_subscribed_event_ops replace\(\) + * + * @old: pointer to :ref:`struct v4l2_event ` with the reported + * event; + * @new: pointer to :ref:`struct v4l2_event ` with the modified + * event; + */ void v4l2_ctrl_replace(struct v4l2_event *old, const struct v4l2_event *new); + +/** + * v4l2_ctrl_merge - Function to be used as a callback to + * &struct v4l2_subscribed_event_ops merge(\) + * + * @old: pointer to :ref:`struct v4l2_event ` with the reported + * event; + * @new: pointer to :ref:`struct v4l2_event ` with the merged + * event; + */ void v4l2_ctrl_merge(const struct v4l2_event *old, struct v4l2_event *new); -/* Can be used as a vidioc_log_status function that just dumps all controls - associated with the filehandle. */ +/** + * v4l2_ctrl_log_status - helper function to implement %VIDIOC_LOG_STATUS ioctl + * + * @file: pointer to struct file + * @fh: unused. Kept just to be compatible to the arguments expected by + * &struct v4l2_ioctl_ops.vidioc_log_status. + * + * Can be used as a vidioc_log_status function that just dumps all controls + * associated with the filehandle. + */ int v4l2_ctrl_log_status(struct file *file, void *fh); -/* Can be used as a vidioc_subscribe_event function that just subscribes - control events. */ +/** + * v4l2_ctrl_subscribe_event - Subscribes to an event + * + * + * @fh: pointer to struct v4l2_fh + * @sub: pointer to &struct v4l2_event_subscription + * + * Can be used as a vidioc_subscribe_event function that just subscribes + * control events. + */ int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, const struct v4l2_event_subscription *sub); -/* Can be used as a poll function that just polls for control events. */ +/** + * v4l2_ctrl_poll - function to be used as a callback to the poll() + * That just polls for control events. + * + * @file: pointer to struct file + * @wait: pointer to struct poll_table_struct + */ unsigned int v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); -/* Helpers for ioctl_ops. If hdl == NULL then they will all return -EINVAL. */ +/* Helpers for ioctl_ops */ + +/** + * v4l2_queryctrl - Helper function to implement + * :ref:`VIDIOC_QUERYCTRL ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @qc: pointer to &struct v4l2_queryctrl + * + * If hdl == NULL then they will all return -EINVAL. + */ int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc); -int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_query_ext_ctrl *qc); + +/** + * v4l2_query_ext_ctrl - Helper function to implement + * :ref:`VIDIOC_QUERY_EXT_CTRL ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @qc: pointer to &struct v4l2_query_ext_ctrl + * + * If hdl == NULL then they will all return -EINVAL. + */ +int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, + struct v4l2_query_ext_ctrl *qc); + +/** + * v4l2_querymenu - Helper function to implement + * :ref:`VIDIOC_QUERYMENU ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @qm: pointer to &struct v4l2_querymenu + * + * If hdl == NULL then they will all return -EINVAL. + */ int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm); + +/** + * v4l2_g_ctrl - Helper function to implement + * :ref:`VIDIOC_G_CTRL ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @ctrl: pointer to &struct v4l2_control + * + * If hdl == NULL then they will all return -EINVAL. + */ int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *ctrl); + +/** + * v4l2_s_ctrl - Helper function to implement + * :ref:`VIDIOC_S_CTRL ` ioctl + * + * @fh: pointer to &struct v4l2_fh + * @hdl: pointer to &struct v4l2_ctrl_handler + * + * @ctrl: pointer to &struct v4l2_control + * + * If hdl == NULL then they will all return -EINVAL. + */ int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, - struct v4l2_control *ctrl); -int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c); -int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *c); + struct v4l2_control *ctrl); + +/** + * v4l2_g_ext_ctrls - Helper function to implement + * :ref:`VIDIOC_G_EXT_CTRLS ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @c: pointer to &struct v4l2_ext_controls + * + * If hdl == NULL then they will all return -EINVAL. + */ +int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, + struct v4l2_ext_controls *c); + +/** + * v4l2_try_ext_ctrls - Helper function to implement + * :ref:`VIDIOC_TRY_EXT_CTRLS ` ioctl + * + * @hdl: pointer to &struct v4l2_ctrl_handler + * @c: pointer to &struct v4l2_ext_controls + * + * If hdl == NULL then they will all return -EINVAL. + */ +int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, + struct v4l2_ext_controls *c); + +/** + * v4l2_s_ext_ctrls - Helper function to implement + * :ref:`VIDIOC_S_EXT_CTRLS ` ioctl + * + * @fh: pointer to &struct v4l2_fh + * @hdl: pointer to &struct v4l2_ctrl_handler + * @c: pointer to &struct v4l2_ext_controls + * + * If hdl == NULL then they will all return -EINVAL. + */ int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, - struct v4l2_ext_controls *c); + struct v4l2_ext_controls *c); -/* Can be used as a subscribe_event function that just subscribes control - events. */ +/** + * v4l2_ctrl_subdev_subscribe_event - Helper function to implement + * as a &struct v4l2_subdev_core_ops subscribe_event function + * that just subscribes control events. + * + * @sd: pointer to &struct v4l2_subdev + * @fh: pointer to &struct v4l2_fh + * @sub: pointer to &struct v4l2_event_subscription + */ int v4l2_ctrl_subdev_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh, struct v4l2_event_subscription *sub); -/* Log all controls owned by subdev's control handler. */ +/** + * v4l2_ctrl_subdev_log_status - Log all controls owned by subdev's control + * handler. + * + * @sd: pointer to &struct v4l2_subdev + */ int v4l2_ctrl_subdev_log_status(struct v4l2_subdev *sd); #endif -- 2.20.1