// SPDX-License-Identifier: GPL-2.0-only
/*
 * One-shot LED Trigger
 *
 * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com>
 *
 * Based on ledtrig-timer.c by Richard Purdie <rpurdie@openedhand.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include "../leds.h"

#define DEFAULT_DELAY 100

struct oneshot_trig_data {
        unsigned int invert;
};

static ssize_t led_shot(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t size)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);
        struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);

        led_blink_set_oneshot(led_cdev,
                        &led_cdev->blink_delay_on, &led_cdev->blink_delay_off,
                        oneshot_data->invert);

        /* content is ignored */
        return size;
}
static ssize_t led_invert_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);

        return sprintf(buf, "%u\n", oneshot_data->invert);
}

static ssize_t led_invert_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t size)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);
        struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
        unsigned long state;
        int ret;

        ret = kstrtoul(buf, 0, &state);
        if (ret)
                return ret;

        oneshot_data->invert = !!state;

        if (oneshot_data->invert)
                led_set_brightness_nosleep(led_cdev, LED_FULL);
        else
                led_set_brightness_nosleep(led_cdev, LED_OFF);

        return size;
}

static ssize_t led_delay_on_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);

        return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
}

static ssize_t led_delay_on_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t size)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);
        unsigned long state;
        int ret;

        ret = kstrtoul(buf, 0, &state);
        if (ret)
                return ret;

        led_cdev->blink_delay_on = state;

        return size;
}

static ssize_t led_delay_off_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);

        return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
}

static ssize_t led_delay_off_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t size)
{
        struct led_classdev *led_cdev = led_trigger_get_led(dev);
        unsigned long state;
        int ret;

        ret = kstrtoul(buf, 0, &state);
        if (ret)
                return ret;

        led_cdev->blink_delay_off = state;

        return size;
}

static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
static DEVICE_ATTR(shot, 0200, NULL, led_shot);

static struct attribute *oneshot_trig_attrs[] = {
        &dev_attr_delay_on.attr,
        &dev_attr_delay_off.attr,
        &dev_attr_invert.attr,
        &dev_attr_shot.attr,
        NULL
};
ATTRIBUTE_GROUPS(oneshot_trig);

static void pattern_init(struct led_classdev *led_cdev)
{
        u32 *pattern;
        unsigned int size = 0;

        pattern = led_get_default_pattern(led_cdev, &size);
        if (!pattern)
                goto out_default;

        if (size != 2) {
                dev_warn(led_cdev->dev,
                         "Expected 2 but got %u values for delays pattern\n",
                         size);
                goto out_default;
        }

        led_cdev->blink_delay_on = pattern[0];
        led_cdev->blink_delay_off = pattern[1];
        kfree(pattern);

        return;

out_default:
        kfree(pattern);
        led_cdev->blink_delay_on = DEFAULT_DELAY;
        led_cdev->blink_delay_off = DEFAULT_DELAY;
}

static int oneshot_trig_activate(struct led_classdev *led_cdev)
{
        struct oneshot_trig_data *oneshot_data;

        oneshot_data = kzalloc_obj(*oneshot_data);
        if (!oneshot_data)
                return -ENOMEM;

        led_set_trigger_data(led_cdev, oneshot_data);

        if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) {
                pattern_init(led_cdev);
                /*
                 * Mark as initialized even on pattern_init() error because
                 * any consecutive call to it would produce the same error.
                 */
                led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
        }

        return 0;
}

static void oneshot_trig_deactivate(struct led_classdev *led_cdev)
{
        struct oneshot_trig_data *oneshot_data = led_get_trigger_data(led_cdev);

        kfree(oneshot_data);

        /* Stop blinking */
        led_set_brightness(led_cdev, LED_OFF);
}

static struct led_trigger oneshot_led_trigger = {
        .name     = "oneshot",
        .activate = oneshot_trig_activate,
        .deactivate = oneshot_trig_deactivate,
        .groups = oneshot_trig_groups,
};
module_led_trigger(oneshot_led_trigger);

MODULE_AUTHOR("Fabio Baltieri <fabio.baltieri@gmail.com>");
MODULE_DESCRIPTION("One-shot LED trigger");
MODULE_LICENSE("GPL v2");