1.17. 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 torch_intensity;
  struct led_flash_setting indicator_intensity;
  u32 flash_faults;
  unsigned int has_external_strobe:1;
};

Members

dev_name[32]

the name of the media entity, unique in the system

torch_intensity

constraints for the LED in torch mode

indicator_intensity

constraints for the indicator 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_flash * 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_flash_init(struct device * dev, struct device_node * of_node, struct led_classdev_flash * fled_cdev, struct led_classdev_flash * iled_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 device_node * of_node

of_node of the LED, may be NULL if the same as device’s

struct led_classdev_flash * fled_cdev

LED flash class device to wrap

struct led_classdev_flash * iled_cdev

LED flash class device representing indicator LED associated with fled_cdev, may be NULL

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.

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.