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

   1 /*
   2  * V4L2 flash LED sub-device registration helpers.
   3  *
   4  *      Copyright (C) 2015 Samsung Electronics Co., Ltd
   5  *      Author: Jacek Anaszewski <j.anaszewski@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #ifndef _V4L2_FLASH_H
  13 #define _V4L2_FLASH_H
  14
  15 #include <media/v4l2-ctrls.h>
  16 #include <media/v4l2-subdev.h>
  17
  18 struct led_classdev_flash;
  19 struct led_classdev;
  20 struct v4l2_flash;
  21 enum led_brightness;
  22
  23 /**
  24  * struct v4l2_flash_ctrl_data - flash control initialization data, filled
  25  *                              basing on the features declared by the LED flash
  26  *                              class driver in the v4l2_flash_config
  27  * @config:     initialization data for a control
  28  * @cid:        contains v4l2 flash control id if the config
  29  *              field was initialized, 0 otherwise
  30  */
  31 struct v4l2_flash_ctrl_data {
  32         struct v4l2_ctrl_config config;
  33         u32 cid;
  34 };
  35
  36 /**
  37  * struct v4l2_flash_ops - V4L2 flash operations
  38  *
  39  * @external_strobe_set: Setup strobing the flash by hardware pin state
  40  *      assertion.
  41  * @intensity_to_led_brightness: Convert intensity to brightness in a device
  42  *      specific manner
  43  * @led_brightness_to_intensity: convert brightness to intensity in a device
  44  *      specific manner.
  45  */
  46 struct v4l2_flash_ops {
  47         int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
  48                                         bool enable);
  49         enum led_brightness (*intensity_to_led_brightness)
  50                 (struct v4l2_flash *v4l2_flash, s32 intensity);
  51         s32 (*led_brightness_to_intensity)
  52                 (struct v4l2_flash *v4l2_flash, enum led_brightness);
  53 };
  54
  55 /**
  56  * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
  57  * @dev_name:                   the name of the media entity,
  58  *                              unique in the system
  59  * @intensity:                  non-flash strobe constraints for the LED
  60  * @flash_faults:               bitmask of flash faults that the LED flash class
  61  *                              device can report; corresponding LED_FAULT* bit
  62  *                              definitions are available in the header file
  63  *                              <linux/led-class-flash.h>
  64  * @has_external_strobe:        external strobe capability
  65  */
  66 struct v4l2_flash_config {
  67         char dev_name[32];
  68         struct led_flash_setting intensity;
  69         u32 flash_faults;
  70         unsigned int has_external_strobe:1;
  71 };
  72
  73 /**
  74  * struct v4l2_flash - Flash sub-device context
  75  * @fled_cdev:          LED flash class device controlled by this sub-device
  76  * @iled_cdev:          LED class device representing indicator LED associated
  77  *                      with the LED flash class device
  78  * @ops:                V4L2 specific flash ops
  79  * @sd:                 V4L2 sub-device
  80  * @hdl:                flash controls handler
  81  * @ctrls:              array of pointers to controls, whose values define
  82  *                      the sub-device state
  83  */
  84 struct v4l2_flash {
  85         struct led_classdev_flash *fled_cdev;
  86         struct led_classdev *iled_cdev;
  87         const struct v4l2_flash_ops *ops;
  88
  89         struct v4l2_subdev sd;
  90         struct v4l2_ctrl_handler hdl;
  91         struct v4l2_ctrl **ctrls;
  92 };
  93
  94 /**
  95  * v4l2_subdev_to_v4l2_flash - Returns a &struct v4l2_flash from the
  96  * &struct v4l2_subdev embedded on it.
  97  *
  98  * @sd: pointer to &struct v4l2_subdev
  99  */
 100 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
 101                                                         struct v4l2_subdev *sd)
 102 {
 103         return container_of(sd, struct v4l2_flash, sd);
 104 }
 105
 106 /**
 107  * v4l2_ctrl_to_v4l2_flash - Returns a &struct v4l2_flash from the
 108  * &struct v4l2_ctrl embedded on it.
 109  *
 110  * @c: pointer to &struct v4l2_ctrl
 111  */
 112 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
 113 {
 114         return container_of(c->handler, struct v4l2_flash, hdl);
 115 }
 116
 117 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
 118 /**
 119  * v4l2_flash_init - initialize V4L2 flash led sub-device
 120  * @dev:        flash device, e.g. an I2C device
 121  * @fwn:        fwnode_handle of the LED, may be NULL if the same as device's
 122  * @fled_cdev:  LED flash class device to wrap
 123  * @ops:        V4L2 Flash device ops
 124  * @config:     initialization data for V4L2 Flash sub-device
 125  *
 126  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
 127  * The ops pointer is stored by the V4L2 flash framework. No
 128  * references are held to config nor its contents once this function
 129  * has returned.
 130  *
 131  * Returns: A valid pointer, or, when an error occurs, the return
 132  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
 133  * PTR_ERR() to obtain the numeric return value.
 134  */
 135 struct v4l2_flash *v4l2_flash_init(
 136         struct device *dev, struct fwnode_handle *fwn,
 137         struct led_classdev_flash *fled_cdev,
 138         const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config);
 139
 140 /**
 141  * v4l2_flash_indicator_init - initialize V4L2 indicator sub-device
 142  * @dev:        flash device, e.g. an I2C device
 143  * @fwn:        fwnode_handle of the LED, may be NULL if the same as device's
 144  * @iled_cdev:  LED flash class device representing the indicator LED
 145  * @config:     initialization data for V4L2 Flash sub-device
 146  *
 147  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
 148  * The ops pointer is stored by the V4L2 flash framework. No
 149  * references are held to config nor its contents once this function
 150  * has returned.
 151  *
 152  * Returns: A valid pointer, or, when an error occurs, the return
 153  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
 154  * PTR_ERR() to obtain the numeric return value.
 155  */
 156 struct v4l2_flash *v4l2_flash_indicator_init(
 157         struct device *dev, struct fwnode_handle *fwn,
 158         struct led_classdev *iled_cdev, struct v4l2_flash_config *config);
 159
 160 /**
 161  * v4l2_flash_release - release V4L2 Flash sub-device
 162  * @v4l2_flash: the V4L2 Flash sub-device to release
 163  *
 164  * Release V4L2 Flash sub-device.
 165  */
 166 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
 167
 168 #else
 169 static inline struct v4l2_flash *v4l2_flash_init(
 170         struct device *dev, struct fwnode_handle *fwn,
 171         struct led_classdev_flash *fled_cdev,
 172         const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
 173 {
 174         return NULL;
 175 }
 176
 177 static inline struct v4l2_flash *v4l2_flash_indicator_init(
 178         struct device *dev, struct fwnode_handle *fwn,
 179         struct led_classdev *iled_cdev, struct v4l2_flash_config *config)
 180 {
 181         return NULL;
 182 }
 183
 184 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
 185 {
 186 }
 187 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
 188
 189 #endif /* _V4L2_FLASH_H */