2.18. V4L2 flash functions and data structures¶
- 
struct v4l2_flash_ctrl_data¶
- flash control initialization data, filled basing on the features declared by the LED flash class driver in the v4l2_flash_config 
Definition:
struct v4l2_flash_ctrl_data {
    struct v4l2_ctrl_config config;
    u32 cid;
};
Members
- config
- initialization data for a control 
- cid
- contains v4l2 flash control id if the config field was initialized, 0 otherwise 
- 
struct v4l2_flash_ops¶
- V4L2 flash operations 
Definition:
struct v4l2_flash_ops {
    int (*external_strobe_set)(struct v4l2_flash *v4l2_flash, bool enable);
    enum led_brightness (*intensity_to_led_brightness) (struct v4l2_flash *v4l2_flash, s32 intensity);
    s32 (*led_brightness_to_intensity) (struct v4l2_flash *v4l2_flash, enum led_brightness);
};
Members
- external_strobe_set
- Setup strobing the flash by hardware pin state assertion. 
- intensity_to_led_brightness
- Convert intensity to brightness in a device specific manner 
- led_brightness_to_intensity
- convert brightness to intensity in a device specific manner. 
- 
struct v4l2_flash_config¶
- V4L2 Flash sub-device initialization data 
Definition:
struct v4l2_flash_config {
    char dev_name[32];
    struct led_flash_setting intensity;
    u32 flash_faults;
    unsigned int has_external_strobe:1;
};
Members
- dev_name
- the name of the media entity, unique in the system 
- intensity
- non-flash strobe constraints for the LED 
- flash_faults
- bitmask of flash faults that the LED flash class device can report; corresponding LED_FAULT* bit definitions are available in the header file <linux/led-class-flash.h> 
- has_external_strobe
- external strobe capability 
- 
struct v4l2_flash¶
- Flash sub-device context 
Definition:
struct v4l2_flash {
    struct led_classdev_flash *fled_cdev;
    struct led_classdev *iled_cdev;
    const struct v4l2_flash_ops *ops;
    struct v4l2_subdev sd;
    struct v4l2_ctrl_handler hdl;
    struct v4l2_ctrl **ctrls;
};
Members
- fled_cdev
- LED flash class device controlled by this sub-device 
- iled_cdev
- LED class device representing indicator LED associated with the LED flash class device 
- ops
- V4L2 specific flash ops 
- sd
- V4L2 sub-device 
- hdl
- flash controls handler 
- ctrls
- array of pointers to controls, whose values define the sub-device state 
- 
struct v4l2_flash *v4l2_subdev_to_v4l2_flash(struct v4l2_subdev *sd)¶
- Returns a - struct v4l2_flashfrom the- struct v4l2_subdevembedded on it.
Parameters
- struct v4l2_subdev *sd
- pointer to - struct v4l2_subdev
- 
struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)¶
- Returns a - struct v4l2_flashfrom the- struct v4l2_ctrlembedded on it.
Parameters
- struct v4l2_ctrl *c
- pointer to - struct v4l2_ctrl
- 
struct v4l2_flash *v4l2_flash_init(struct device *dev, struct fwnode_handle *fwn, struct led_classdev_flash *fled_cdev, const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)¶
- initialize V4L2 flash led sub-device 
Parameters
- struct device *dev
- flash device, e.g. an I2C device 
- struct fwnode_handle *fwn
- fwnode_handle of the LED, may be NULL if the same as device’s 
- struct led_classdev_flash *fled_cdev
- LED flash class device to wrap 
- const struct v4l2_flash_ops *ops
- V4L2 Flash device ops 
- struct v4l2_flash_config *config
- initialization data for V4L2 Flash sub-device 
Description
Create V4L2 Flash sub-device wrapping given LED subsystem device. The ops pointer is stored by the V4L2 flash framework. No references are held to config nor its contents once this function has returned.
Return
A valid pointer, or, when an error occurs, the return
value is encoded using ERR_PTR(). Use IS_ERR() to check and
PTR_ERR() to obtain the numeric return value.
- 
struct v4l2_flash *v4l2_flash_indicator_init(struct device *dev, struct fwnode_handle *fwn, struct led_classdev *iled_cdev, struct v4l2_flash_config *config)¶
- initialize V4L2 indicator sub-device 
Parameters
- struct device *dev
- flash device, e.g. an I2C device 
- struct fwnode_handle *fwn
- fwnode_handle of the LED, may be NULL if the same as device’s 
- struct led_classdev *iled_cdev
- LED flash class device representing the indicator LED 
- struct v4l2_flash_config *config
- initialization data for V4L2 Flash sub-device 
Description
Create V4L2 Flash sub-device wrapping given LED subsystem device. The ops pointer is stored by the V4L2 flash framework. No references are held to config nor its contents once this function has returned.
Return
A valid pointer, or, when an error occurs, the return
value is encoded using ERR_PTR(). Use IS_ERR() to check and
PTR_ERR() to obtain the numeric return value.
- 
void v4l2_flash_release(struct v4l2_flash *v4l2_flash)¶
- release V4L2 Flash sub-device 
Parameters
- struct v4l2_flash *v4l2_flash
- the V4L2 Flash sub-device to release 
Description
Release V4L2 Flash sub-device.