1.文件: mm-camera2/media-controller/modules/sensors/actuator/actuator.h中对actuator_data_t进行了如下定义:
这个结构体是actuator马达控制的最外层的数据结构。
typedef struct {
int32_t fd;
actuator_ctrl_t *ctrl;
int16_t curr_step_pos;
int16_t cur_restore_pos;
uint16_t total_steps;
uint8_t is_af_supported;
uint8_t cam_name;
uinit8_t load_params;
} actuator_data_t;1.1. fd ---> 与内核进行交互的文件描述述(节点名称？？？ 节点名称为/dev/v4l-subdev4)。
1.2 ctrl ---> 重点结构体，其中我们定义的不同sensor的参数即是actuator_ctrl_t结构体，这是3A算法对外进行的参数配置接口。
1.3 curr_step_pos ---> 这个是一直变化的，它的作用是保存马达当前所处的位置。
1.4 cur_restore_pos ---> 进行马达复位是的位置设定。
1.5 total_steps ---> 表示马达可移动的总步数。它由下面代码计算所得:
- total_steps = af_tune_ptr->af_algo.position_far_end -
- af_tune_ptr->af_algo.position_near_end + 1;
- total_steps += af_tune_ptr->af_algo.undershoot_adjust;
1.6 is_af_supported ---> 代表sensor是否支持自动对焦，是在actuator模块的初始化函数中通过ioctl与底层交互获取
1.7 cam_name ---> camera name,获取同上一起获取，这个名字的作用主要是与我们定义的若干文件进行加载时匹配，根据头文件中af_tune.af_header_info.cam_name字段进行匹配加载，(对于200与201camera的不同处理即是在底层赋给不同的值在实现加载不同的头文件)。
1.8 load_params ---> 代表头文件是否加载，初始值设为1，加载完成后将其置0，后面则不会重复加载。
2.下面主要看actuator_ctrl_t结构体，我们定义的头文件也即此结构体。
- typedef struct {
- af_tunne_parms_t af_tune;
- } actuator_ctrl_t;
af_tunne_parms_t结构体各个版本的定义不同，0208/0301，故其定义在各自的文件目录下，我们使用的是0301版本，其定义文件为mm-camera2/media-controller/modules/sensors/actuators/0301/af_tunning.h
2.1 结构体af_header_info (变量af_header_info) 定义如下:
/** _af_header_info:
**/
typedef struct _af_header_info {
uint16_t header_version; // 头文件版本
enum af_camera_name cam_name; // camera 名字
char module_name[MAX_ACT_MOD_NAME_SIZE]; //模块名称
char actuator_name[MAX_ACT_NAME_SIZE]; //马达名称
}af_header_info_t;成员1. uint16_t header_version = 0x301;
- /* header_version */
成员2. enum af_camera_name af_camera_name cam_name = ACTUATOR_MAIN_CAM_1;
- /* module_name */
其取值范围如下:
enum af_camera_name {
ACTUATOR_MAIN_CAM_0,
ACTUATOR_MAIN_CAM_1,
ACTUATOR_MAIN_CAM_2,
ACTUATOR_MAIN_CAM_3,
ACTUATOR_MAIN_CAM_4,
ACTUATOR_MAIN_CAM_5,
ACTUATOR_WEB_CAM_0,
ACTUATOR_WEB_CAM_1,
ACTUATOR_WEB_CAM_2,
};成员3. char module_name[MAX_ACT_MOD_NAME_SIZE] = "abico";
- /* module_name */
成员4. char actuator_name[MAX_ACT_NAME_SIZE] = "dw9714";
- /* actuator_name */
主要成员cam_name,此处定义的名字将会与上面通过ioctl获取的名字进行匹配，如果匹配成功，则加载此头文件。实现代码如下:
if (af_actuator_ptr->is_af_supported) {
for (cnt = 0; cnt < (sizeof(actuators) / sizeof(actuators[0][0])/
ACTUATOR_CAM_MODE_MAX); cnt++) {
if (af_actuator_ptr->cam_name == actuators[cam_mode][cnt].af_tune.
af_header_info.cam_name) {
af_actuator_ptr->ctrl = &actuators[cam_mode][cnt]; //将头文件的定义进行赋值
break;
}
}
}2.2 结构体af_tuning_alog_t(变量af_algo)定义如下:
/** _af_tuning_algo: AF tuning parameters specific to AF
* algorithm.
*
* @af_process_type: af algorithm type used // AF的处理算法选择
*
* @position_near_end: nearest position lens can move to
*
* @position_default_in_macro: default lens rest position when
* focus mode is Macro.
*
* @position_boundary: determines near end of search range for
* Normal focus mode.
*
* @position_default_in_normal: default lens reset position
* when focus mode is other than
* macro.
*
* @position_far_end: farthest point of the search range
*
* @position_normal_hyperfocal: normal position of the lens when
* focus fails
*
* @undershoot_protect: when enabled, lens will be moved more
* in either forward or backward direction.
* @undershoot_adjust: when undershoot_protect is enabled, lens
* movement is adjusted by this amount.
*
* @fv_drop_allowance: amount by which fv is allowed to drop
* below max
*
* @lef_af_assist_enable: enable/disable led assisted AF
*
* @led_af_assist_trigger_idx: Lux Index燼t which LED assist
* for autofocus is enabled.
*
* @af_tuning_continuous_t: af parameters for continuous focus
*
* @af_exh: af parameters for exhaustive af
*
* @af_sad: sad related tuning parameters
*
* @af_shake_resistant: tuning parameters for af shake
* resistant.
*
* @af_motion_sensor: trigger parameters for af motion sensor.
**/
typedef struct _af_tuning_algo {
unsigned short af_process_type;
unsigned short position_near_end;
unsigned short position_default_in_macro;
unsigned short position_boundary;
unsigned short position_default_in_normal;
unsigned short position_far_end;
unsigned short position_normal_hyperfocal;
unsigned short position_macro_rgn;
unsigned short undershoot_protect;
unsigned short undershoot_adjust;
float fv_drop_allowance;
int lef_af_assist_enable;
long led_af_assist_trigger_idx;
int lens_reset_frame_skip_cnt;
float low_light_gain_th;
af_tuning_continuous_t af_cont;
af_tuning_exhaustive_t af_exh;
af_tuning_fullsweep_t af_full;
af_tuning_sp_t af_sp;
af_shake_resistant_t af_shake_resistant;
af_motion_sensor_t af_motion_sensor;
}af_tuning_algo_t;成员1. unsigned short af_process_type = AF_EXHAUSTIVE_SEARCH;
变量的赋值由下列枚举类型决定:
/* Variable name: af_process_type.
* Defines which AF algorithm to use -
* Exhaustive/Slope-predictive/Continuous.
* 3A version:
* Default value: AF_EXHAUSTIVE_SEARCH.
* Data range: based on af_algo_type
*/
AF_EXHAUSTIVE_SEARCH, (其值为下列枚举类型中列出)
/******************************************************************************
AF Algorithm tuning parameters AF算法调试选择
******************************************************************************/
/** af_algo_type: Type of algorithm currently supported
**/
typedef enum {
AF_PROCESS_DEFAULT = -2, // 默认算法
AF_PROCESS_UNCHANGED = -1, // UNCHANGED
AF_EXHAUSTIVE_SEARCH = 0, // 穷举算法
AF_EXHAUSTIVE_FAST, // 快速穷举法
AF_HILL_CLIMBING_CONSERVATIVE, // 保守爬山算法
AF_HILL_CLIMBING_DEFAULT, // 默认爬上算法
AF_HILL_CLIMBING_AGGRESSIVE, // 激进爬山算法
AF_FULL_SWEEP, // 扫描线算法
AF_SLOPE_PREDICTIVE_SEARCH, // 坡度预测算法
AF_CONTINUOUS_SEARCH, // 连续搜索算法
AF_PROCESS_MAX
} af_algo_type;成员2. unsigned short position_near_end = 0;
/* Variable name: position_near_end.
* Used to control how far lens can move away from mechanical stop. It
* is defined in term of indices, where position_far_end >
* position_near_end.
* 3A version:
* Default value: 0.
* Data range: 0 to (position_far_end - 1).
* Constraints: Less than position_far_end. Total steps for AF lens to
* travel = position_far_end - position_near_end. For
* sanity check, it should be more than 20 steps.
* Effect: Non-zero means we are limiting AF travel range even more than
* the values obtained from AF tuning. For example, if AF lens
* on the final production modules move 8 steps beyond the
* necessary MACRO focused distance, we can reduce travel range
* by setting position_near_end to 8 (or less to account for
* module-to-module variation).
*/用于控制镜头在多远处机械停止的位置，这个被定义为position_far_end > position_near_end.
成员3. unsigned short position_default_in_macro = 0;
/* Variable name: position_default_in_macro.
* Gives default rest position of lens when focus mode is Macro.
* 3A version:
* Default value: 0.
* Data range: 0 to position_far_end.
*/在对焦方式为无限远时，给出镜头静止时的默认位置，范围为: 0 - position_far_end
成员4. unsigned short position_boundary = 35;
/* Variable name: position_boundary.
* Used to control how far lens can move away from mechanical stop in
* NORMAL search mode.
* 3A version:
* Default value: 0.
* Data range: 0 to (position_far_end - 1).
* Constraints: Less than position_far_end.
* Effect: The closer it is to position_far_end, the less steps AF lens is allowed
* to travel in NORMAL search mode.
*/位置边界
成员5. unsigned short position_default_in_normal = 40;
/* Variable name: position_default_in_normal.
* Gives default rest position of lens when focus mode is Normal/Auto.
* mode.
* 3A version:
* Default value: position_far_end.
* Data range: 0 to position_far_end.
*/成员6. unsigned short position_far_end = 45;
/* Variable name: position_far_end.
* Used to control how far lens can move away from mechanical stop. It is
* defined in term of indices, where position_far_end > position_near_end.
* 3A version:
* Default value: actuator infinity position
* Data range: 1 to infinty
* Constraints:
* Effect: Non-zero means we are limiting AF travel range even more than the
* values obtained from AF tuning.
*/成员7. unsigned short position_normal_hyperfocal = 38;
/* Variable name: position_normal_hyperfocal.
* Gives default position of lens when focus mode is Normal/Auto and
* focus fails.
* 3A version:
* Default value: position_far_end.
* Data range: 0 to position_far_end.
*/成员8. unsigned short position_macro_rgn = 18;
/* Variable name: position_macro_rgn.
* Starting lens position of macro region.
* 3A version:
* Default value: tunable..
* Data range: 0 to position_far_end.
*/成员9. unsigned short undershoot_protect = 0;
/* Variable name: undershoot_protect.
* Boolean flag to enable/disable the feature
* 3A version:
* Default value: 0 (disable)
* Data range: 0 (enable) or 1 (disable)
* Constraints: the degree of protection from undershoot will be depends
* on undershoot_adjust variable
* Effect: If this feature is enabled, lens will move more in one
* direction over the other direction. This is needed when
* it is determined that AF actuator has severe hysteresis on
* its movement during characterization process. The feature
* compensate hysteresis by moving the lens more
* in either forward or backward direction.
*/成员10. unsigned short undershoot_adjust = 0;
/* Variable name: undershoot_adjust.
* Used when undershoot protection is enabled.
* 3A version:
* Default value: 0
* Data range: 0 to (coarse step size - 1)
* Constraints: As noted above, number greater than or equal to coarse
* step size is not recommended.
* Effect: When feature is turned on, the feature will compensate the
* undershoot movement of lens (mainly due to severe hysteresis)
* by moving extra step specified in this variable.
*/成员11.float fv_drop_allowance = 0.55;
/* Variable name: fv_drop_allowance.
* If focus value drops below this much of maximum fv, search forward
* is stopped.
* 3A version:
* Default value: 0.5
* Data range: 0 to less than 1
* Constraints: Value less than 0.75 is recommended.
* Effect: Increasing this value makes it easier to stop the search
* forward.
*/成员12.int lef_af_assist_enable = 1;
/* Variable name: lef_af_assist_enable.
* Enable or disable the LED assist for auto focus feature.
* 3A version:
* Default value: 0.5
* Data range: 1 or 0.
* Constraints: None
* Effect: LED auto focus assist is enabled.
*/成员13.long led_af_assist_trigger_idx = 372;
/* Variable name: led_af_assist_trigger_idx.
* Lux Index燼t which LED assist for autofocus is enabled.
* 3A version:
* Default value: wLED Trigger Index (calculated)
* Data range: 0 to 1000
* Constraints: None
* Effect: Selects scene brightness level at which LED auto focus assist
* can be enabled.
*/成员14.int lens_reset_frame_skip_cnt = 6;
/* Variable name: lens_reset_frame_skip_cnt
* How many frames to skip after resetting the lens
* 3A version:
* Default value: 2
* Data range: 2 - 6
* Constraints: Integers
* Effect: Bigger in value represents longer waiting time.
*/成员15.float low_light_gain_th = 10;
/* Variable name: low_light_gain_th
* When the aec gain is above this threshold, we assume it's low light condition.
* 3A version:
* Default value: 10
* Data range:
* Constraints:
* Effect:
*/成员16.af_tuning_continuous_t af_cont;
af_tunning_continuous_t定义如下:
/** _af_tuning_continuous: AF tuning parameters specific to
* Continuous AF
*
* @enable: CAF is enabled/disabled (currently only used by
* ez-tune)
*
* @scene_change_detection_ratio: fv change to trigger a
* target change
*
* @panning_stable_fv_change_trigger: fv change vs past
* frame fv to trigger to
*