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

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * V4L2 flash LED sub-device registration helpers.
   4  *
   5  *      Copyright (C) 2015 Samsung Electronics Co., Ltd
   6  *      Author: Jacek Anaszewski <j.anaszewski@samsung.com>
   7  */
   8
   9 #ifndef _V4L2_FLASH_H
  10 #define _V4L2_FLASH_H
  11
  12 #include <media/v4l2-ctrls.h>
  13 #include <media/v4l2-subdev.h>
  14
  15 struct led_classdev_flash;
  16 struct led_classdev;
  17 struct v4l2_flash;
  18 enum led_brightness;
  19
  20 /**
  21  * struct v4l2_flash_ctrl_data - flash control initialization data, filled
  22  *                              basing on the features declared by the LED flash
  23  *                              class driver in the v4l2_flash_config
  24  * @config:     initialization data for a control
  25  * @cid:        contains v4l2 flash control id if the config
  26  *              field was initialized, 0 otherwise
  27  */
  28 struct v4l2_flash_ctrl_data {
  29         struct v4l2_ctrl_config config;
  30         u32 cid;
  31 };
  32
  33 /**
  34  * struct v4l2_flash_ops - V4L2 flash operations
  35  *
  36  * @external_strobe_set: Setup strobing the flash by hardware pin state
  37  *      assertion.
  38  * @intensity_to_led_brightness: Convert intensity to brightness in a device
  39  *      specific manner
  40  * @led_brightness_to_intensity: convert brightness to intensity in a device
  41  *      specific manner.
  42  */
  43 struct v4l2_flash_ops {
  44         int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
  45                                         bool enable);
  46         enum led_brightness (*intensity_to_led_brightness)
  47                 (struct v4l2_flash *v4l2_flash, s32 intensity);
  48         s32 (*led_brightness_to_intensity)
  49                 (struct v4l2_flash *v4l2_flash, enum led_brightness);
  50 };
  51
  52 /**
  53  * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
  54  * @dev_name:                   the name of the media entity,
  55  *                              unique in the system
  56  * @intensity:                  non-flash strobe constraints for the LED
  57  * @flash_faults:               bitmask of flash faults that the LED flash class
  58  *                              device can report; corresponding LED_FAULT* bit
  59  *                              definitions are available in the header file
  60  *                              <linux/led-class-flash.h>
  61  * @has_external_strobe:        external strobe capability
  62  */
  63 struct v4l2_flash_config {
  64         char dev_name[32];
  65         struct led_flash_setting intensity;
  66         u32 flash_faults;
  67         unsigned int has_external_strobe:1;
  68 };
  69
  70 /**
  71  * struct v4l2_flash - Flash sub-device context
  72  * @fled_cdev:          LED flash class device controlled by this sub-device
  73  * @iled_cdev:          LED class device representing indicator LED associated
  74  *                      with the LED flash class device
  75  * @ops:                V4L2 specific flash ops
  76  * @sd:                 V4L2 sub-device
  77  * @hdl:                flash controls handler
  78  * @ctrls:              array of pointers to controls, whose values define
  79  *                      the sub-device state
  80  */
  81 struct v4l2_flash {
  82         struct led_classdev_flash *fled_cdev;
  83         struct led_classdev *iled_cdev;
  84         const struct v4l2_flash_ops *ops;
  85
  86         struct v4l2_subdev sd;
  87         struct v4l2_ctrl_handler hdl;
  88         struct v4l2_ctrl **ctrls;
  89 };
  90
  91 /**
  92  * v4l2_subdev_to_v4l2_flash - Returns a &struct v4l2_flash from the
  93  * &struct v4l2_subdev embedded on it.
  94  *
  95  * @sd: pointer to &struct v4l2_subdev
  96  */
  97 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
  98                                                         struct v4l2_subdev *sd)
  99 {
 100         return container_of(sd, struct v4l2_flash, sd);
 101 }
 102
 103 /**
 104  * v4l2_ctrl_to_v4l2_flash - Returns a &struct v4l2_flash from the
 105  * &struct v4l2_ctrl embedded on it.
 106  *
 107  * @c: pointer to &struct v4l2_ctrl
 108  */
 109 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
 110 {
 111         return container_of(c->handler, struct v4l2_flash, hdl);
 112 }
 113
 114 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
 115 /**
 116  * v4l2_flash_init - initialize V4L2 flash led sub-device
 117  * @dev:        flash device, e.g. an I2C device
 118  * @fwn:        fwnode_handle of the LED, may be NULL if the same as device's
 119  * @fled_cdev:  LED flash class device to wrap
 120  * @ops:        V4L2 Flash device ops
 121  * @config:     initialization data for V4L2 Flash sub-device
 122  *
 123  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
 124  * The ops pointer is stored by the V4L2 flash framework. No
 125  * references are held to config nor its contents once this function
 126  * has returned.
 127  *
 128  * Returns: A valid pointer, or, when an error occurs, the return
 129  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
 130  * PTR_ERR() to obtain the numeric return value.
 131  */
 132 struct v4l2_flash *v4l2_flash_init(
 133         struct device *dev, struct fwnode_handle *fwn,
 134         struct led_classdev_flash *fled_cdev,
 135         const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config);
 136
 137 /**
 138  * v4l2_flash_indicator_init - initialize V4L2 indicator sub-device
 139  * @dev:        flash device, e.g. an I2C device
 140  * @fwn:        fwnode_handle of the LED, may be NULL if the same as device's
 141  * @iled_cdev:  LED flash class device representing the indicator LED
 142  * @config:     initialization data for V4L2 Flash sub-device
 143  *
 144  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
 145  * The ops pointer is stored by the V4L2 flash framework. No
 146  * references are held to config nor its contents once this function
 147  * has returned.
 148  *
 149  * Returns: A valid pointer, or, when an error occurs, the return
 150  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
 151  * PTR_ERR() to obtain the numeric return value.
 152  */
 153 struct v4l2_flash *v4l2_flash_indicator_init(
 154         struct device *dev, struct fwnode_handle *fwn,
 155         struct led_classdev *iled_cdev, struct v4l2_flash_config *config);
 156
 157 /**
 158  * v4l2_flash_release - release V4L2 Flash sub-device
 159  * @v4l2_flash: the V4L2 Flash sub-device to release
 160  *
 161  * Release V4L2 Flash sub-device.
 162  */
 163 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
 164
 165 #else
 166 static inline struct v4l2_flash *v4l2_flash_init(
 167         struct device *dev, struct fwnode_handle *fwn,
 168         struct led_classdev_flash *fled_cdev,
 169         const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
 170 {
 171         return NULL;
 172 }
 173
 174 static inline struct v4l2_flash *v4l2_flash_indicator_init(
 175         struct device *dev, struct fwnode_handle *fwn,
 176         struct led_classdev *iled_cdev, struct v4l2_flash_config *config)
 177 {
 178         return NULL;
 179 }
 180
 181 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
 182 {
 183 }
 184 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
 185
 186 #endif /* _V4L2_FLASH_H */