linux-imx

/*

 * V4L2 flash LED sub-device registration helpers.

 *

 *  Copyright (C) 2015 Samsung Electronics Co., Ltd

 *  Author: Jacek Anaszewski <j.anaszewski@samsung.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

​

#include <linux/led-class-flash.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/property.h>

#include <linux/slab.h>

#include <linux/types.h>

#include <media/v4l2-flash-led-class.h>

​

#define has_flash_op(v4l2_flash, op)                \

    (v4l2_flash && v4l2_flash->ops && v4l2_flash->ops->op)

​

#define call_flash_op(v4l2_flash, op, arg)          \

        (has_flash_op(v4l2_flash, op) ?         \

            v4l2_flash->ops->op(v4l2_flash, arg) :  \

            -EINVAL)

​

enum ctrl_init_data_id {

    LED_MODE,

    TORCH_INTENSITY,

    FLASH_INTENSITY,

    INDICATOR_INTENSITY,

    FLASH_TIMEOUT,

    STROBE_SOURCE,

    /*

     * Only above values are applicable to

     * the 'ctrls' array in the struct v4l2_flash.

     */

    FLASH_STROBE,

    STROBE_STOP,

    STROBE_STATUS,

    FLASH_FAULT,

    NUM_FLASH_CTRLS,

};

​

static enum led_brightness __intensity_to_led_brightness(

                    struct v4l2_ctrl *ctrl, s32 intensity)

{

    intensity -= ctrl->minimum;

    intensity /= (u32) ctrl->step;

​

    /*

     * Indicator LEDs, unlike torch LEDs, are turned on/off basing on

     * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.

     * Therefore it must be possible to set it to 0 level which in

     * the LED subsystem reflects LED_OFF state.

     */

    if (ctrl->minimum)

        ++intensity;

​

    return intensity;

}

​

static s32 __led_brightness_to_intensity(struct v4l2_ctrl *ctrl,

                     enum led_brightness brightness)

{

    /*

     * Indicator LEDs, unlike torch LEDs, are turned on/off basing on

     * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.

     * Do not decrement brightness read from the LED subsystem for

     * indicator LED as it may equal 0. For torch LEDs this function

     * is called only when V4L2_FLASH_LED_MODE_TORCH is set and the

     * brightness read is guaranteed to be greater than 0. In the mode

     * V4L2_FLASH_LED_MODE_NONE the cached torch intensity value is used.

     */

    if (ctrl->id != V4L2_CID_FLASH_INDICATOR_INTENSITY)

        --brightness;

​

    return (brightness * ctrl->step) + ctrl->minimum;

}

​

static void v4l2_flash_set_led_brightness(struct v4l2_flash *v4l2_flash,

                    struct v4l2_ctrl *ctrl)

{

    struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;

    enum led_brightness brightness;

​

    if (has_flash_op(v4l2_flash, intensity_to_led_brightness))

        brightness = call_flash_op(v4l2_flash,

                    intensity_to_led_brightness,

                    ctrl->val);

    else