include/media/v4l2-flash-led-class.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  * V4L2 flash LED sub-device registration helpers.
0004  *
0005  *  Copyright (C) 2015 Samsung Electronics Co., Ltd
0006  *  Author: Jacek Anaszewski <j.anaszewski@samsung.com>
0007  */
0008
0009 #ifndef _V4L2_FLASH_H
0010 #define _V4L2_FLASH_H
0011
0012 #include <media/v4l2-ctrls.h>
0013 #include <media/v4l2-subdev.h>
0014
0015 struct led_classdev_flash;
0016 struct led_classdev;
0017 struct v4l2_flash;
0018 enum led_brightness;
0019
0020 /**
0021  * struct v4l2_flash_ctrl_data - flash control initialization data, filled
0022  *              basing on the features declared by the LED flash
0023  *              class driver in the v4l2_flash_config
0024  * @config: initialization data for a control
0025  * @cid:    contains v4l2 flash control id if the config
0026  *      field was initialized, 0 otherwise
0027  */
0028 struct v4l2_flash_ctrl_data {
0029     struct v4l2_ctrl_config config;
0030     u32 cid;
0031 };
0032
0033 /**
0034  * struct v4l2_flash_ops - V4L2 flash operations
0035  *
0036  * @external_strobe_set: Setup strobing the flash by hardware pin state
0037  *  assertion.
0038  * @intensity_to_led_brightness: Convert intensity to brightness in a device
0039  *  specific manner
0040  * @led_brightness_to_intensity: convert brightness to intensity in a device
0041  *  specific manner.
0042  */
0043 struct v4l2_flash_ops {
0044     int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
0045                     bool enable);
0046     enum led_brightness (*intensity_to_led_brightness)
0047         (struct v4l2_flash *v4l2_flash, s32 intensity);
0048     s32 (*led_brightness_to_intensity)
0049         (struct v4l2_flash *v4l2_flash, enum led_brightness);
0050 };
0051
0052 /**
0053  * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
0054  * @dev_name:           the name of the media entity,
0055  *              unique in the system
0056  * @intensity:          non-flash strobe constraints for the LED
0057  * @flash_faults:       bitmask of flash faults that the LED flash class
0058  *              device can report; corresponding LED_FAULT* bit
0059  *              definitions are available in the header file
0060  *              <linux/led-class-flash.h>
0061  * @has_external_strobe:    external strobe capability
0062  */
0063 struct v4l2_flash_config {
0064     char dev_name[32];
0065     struct led_flash_setting intensity;
0066     u32 flash_faults;
0067     unsigned int has_external_strobe:1;
0068 };
0069
0070 /**
0071  * struct v4l2_flash - Flash sub-device context
0072  * @fled_cdev:      LED flash class device controlled by this sub-device
0073  * @iled_cdev:      LED class device representing indicator LED associated
0074  *          with the LED flash class device
0075  * @ops:        V4L2 specific flash ops
0076  * @sd:         V4L2 sub-device
0077  * @hdl:        flash controls handler
0078  * @ctrls:      array of pointers to controls, whose values define
0079  *          the sub-device state
0080  */
0081 struct v4l2_flash {
0082     struct led_classdev_flash *fled_cdev;
0083     struct led_classdev *iled_cdev;
0084     const struct v4l2_flash_ops *ops;
0085
0086     struct v4l2_subdev sd;
0087     struct v4l2_ctrl_handler hdl;
0088     struct v4l2_ctrl **ctrls;
0089 };
0090
0091 /**
0092  * v4l2_subdev_to_v4l2_flash - Returns a &struct v4l2_flash from the
0093  * &struct v4l2_subdev embedded on it.
0094  *
0095  * @sd: pointer to &struct v4l2_subdev
0096  */
0097 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
0098                             struct v4l2_subdev *sd)
0099 {
0100     return container_of(sd, struct v4l2_flash, sd);
0101 }
0102
0103 /**
0104  * v4l2_ctrl_to_v4l2_flash - Returns a &struct v4l2_flash from the
0105  * &struct v4l2_ctrl embedded on it.
0106  *
0107  * @c: pointer to &struct v4l2_ctrl
0108  */
0109 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
0110 {
0111     return container_of(c->handler, struct v4l2_flash, hdl);
0112 }
0113
0114 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
0115 /**
0116  * v4l2_flash_init - initialize V4L2 flash led sub-device
0117  * @dev:    flash device, e.g. an I2C device
0118  * @fwn:    fwnode_handle of the LED, may be NULL if the same as device's
0119  * @fled_cdev:  LED flash class device to wrap
0120  * @ops:    V4L2 Flash device ops
0121  * @config: initialization data for V4L2 Flash sub-device
0122  *
0123  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
0124  * The ops pointer is stored by the V4L2 flash framework. No
0125  * references are held to config nor its contents once this function
0126  * has returned.
0127  *
0128  * Returns: A valid pointer, or, when an error occurs, the return
0129  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
0130  * PTR_ERR() to obtain the numeric return value.
0131  */
0132 struct v4l2_flash *v4l2_flash_init(
0133     struct device *dev, struct fwnode_handle *fwn,
0134     struct led_classdev_flash *fled_cdev,
0135     const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config);
0136
0137 /**
0138  * v4l2_flash_indicator_init - initialize V4L2 indicator sub-device
0139  * @dev:    flash device, e.g. an I2C device
0140  * @fwn:    fwnode_handle of the LED, may be NULL if the same as device's
0141  * @iled_cdev:  LED flash class device representing the indicator LED
0142  * @config: initialization data for V4L2 Flash sub-device
0143  *
0144  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
0145  * The ops pointer is stored by the V4L2 flash framework. No
0146  * references are held to config nor its contents once this function
0147  * has returned.
0148  *
0149  * Returns: A valid pointer, or, when an error occurs, the return
0150  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
0151  * PTR_ERR() to obtain the numeric return value.
0152  */
0153 struct v4l2_flash *v4l2_flash_indicator_init(
0154     struct device *dev, struct fwnode_handle *fwn,
0155     struct led_classdev *iled_cdev, struct v4l2_flash_config *config);
0156
0157 /**
0158  * v4l2_flash_release - release V4L2 Flash sub-device
0159  * @v4l2_flash: the V4L2 Flash sub-device to release
0160  *
0161  * Release V4L2 Flash sub-device.
0162  */
0163 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
0164
0165 #else
0166 static inline struct v4l2_flash *v4l2_flash_init(
0167     struct device *dev, struct fwnode_handle *fwn,
0168     struct led_classdev_flash *fled_cdev,
0169     const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
0170 {
0171     return NULL;
0172 }
0173
0174 static inline struct v4l2_flash *v4l2_flash_indicator_init(
0175     struct device *dev, struct fwnode_handle *fwn,
0176     struct led_classdev *iled_cdev, struct v4l2_flash_config *config)
0177 {
0178     return NULL;
0179 }
0180
0181 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
0182 {
0183 }
0184 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
0185
0186 #endif /* _V4L2_FLASH_H */