#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/workqueue.h>
#include <linux/gpio.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of.h>
#include <linux/spinlock.h>
#include <linux/wakelock.h>
#include <linux/hall.h>
#include <linux/sec_class.h>

#if defined(CONFIG_HALL_NEW_NODE)
extern struct device *hall_ic;
#endif

struct device *sec_device_create(void *drvdata, const char *fmt);

struct certify_hall_drvdata {
	struct input_dev *input;
	struct hall_platform_data *pdata;
	struct work_struct work;
	struct delayed_work certify_cover_dwork;
	struct wake_lock certify_wake_lock;
	u8 event_val;
};

static bool certify_cover;

static ssize_t certify_hall_detect_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	if (certify_cover)
		sprintf(buf, "CLOSE\n");
	else
		sprintf(buf, "OPEN\n");

	return strlen(buf);
}
static DEVICE_ATTR_RO(certify_hall_detect);

static struct attribute *certify_hall_attrs[] = {
	&dev_attr_certify_hall_detect.attr,
	NULL,
};

static struct attribute_group certify_hall_attr_group = {
	.attrs = certify_hall_attrs,
};

#ifdef CONFIG_SEC_FACTORY
static void certify_cover_work(struct work_struct *work)
{
	bool first, second;
	struct certify_hall_drvdata *ddata =
		container_of(work, struct certify_hall_drvdata,
				certify_cover_dwork.work);

	first = !gpio_get_value(ddata->pdata->gpio_certify_cover);

	pr_info("[keys] %s certify_status #1 : %d (%s)\n", __func__, first,
			first ? "attach" : "detach");

	msleep(50);

	second = !gpio_get_value(ddata->pdata->gpio_certify_cover);

	pr_info("[keys] %s certify_status #2 : %d (%s)\n", __func__, second,
			second ? "attach" : "detach");

	if (first == second) {
		certify_cover = first;

		input_report_switch(ddata->input, ddata->event_val,
				certify_cover);
		input_sync(ddata->input);
	}
}
#else
static void certify_cover_work(struct work_struct *work)
{
	bool first;
	struct certify_hall_drvdata *ddata =
		container_of(work, struct certify_hall_drvdata,
				certify_cover_dwork.work);

	first = !gpio_get_value(ddata->pdata->gpio_certify_cover);

	pr_info("[keys] %s certify_status : %d (%s)\n", __func__, first,
			first ? "attach" : "detach");

	certify_cover = first;

	input_report_switch(ddata->input, ddata->event_val, certify_cover);
	input_sync(ddata->input);
}
#endif

static void __certify_cover_detect(struct certify_hall_drvdata *ddata,
		bool flip_certify_status)
{
	cancel_delayed_work_sync(&ddata->certify_cover_dwork);
#ifdef CONFIG_SEC_FACTORY
	schedule_delayed_work(&ddata->certify_cover_dwork, HZ / 20);
#else
	if (flip_certify_status) {
		/* 50ms */
		wake_lock_timeout(&ddata->certify_wake_lock, HZ * 5 / 100);
		/* 10ms */
		schedule_delayed_work(&ddata->certify_cover_dwork,
				HZ * 1 / 100);
	} else {
		wake_unlock(&ddata->certify_wake_lock);
		schedule_delayed_work(&ddata->certify_cover_dwork, 0);
	}
#endif
}

static irqreturn_t certify_cover_detect(int irq, void *dev_id)
{
	bool flip_certify_status;
	struct certify_hall_drvdata *ddata = dev_id;

	flip_certify_status = !gpio_get_value(ddata->pdata->gpio_certify_cover);

	pr_info("keys:%s certify_status : %d\n", __func__, flip_certify_status);

	__certify_cover_detect(ddata, flip_certify_status);

	return IRQ_HANDLED;
}

static int certify_hall_open(struct input_dev *input)
{
	struct certify_hall_drvdata *ddata = input_get_drvdata(input);

	/* update the current status */
	schedule_delayed_work(&ddata->certify_cover_dwork, HZ / 2);
	/* Report current state of buttons that are connected to GPIOs */
	input_sync(input);

	return 0;
}

static void certify_hall_close(struct input_dev *input)
{
}


static void init_certify_hall_ic_irq(struct input_dev *input)
{
	struct certify_hall_drvdata *ddata = input_get_drvdata(input);

	int ret = 0;
	int irq = ddata->pdata->irq_certify_cover;

	certify_cover = gpio_get_value(ddata->pdata->gpio_certify_cover);

	INIT_DELAYED_WORK(&ddata->certify_cover_dwork, certify_cover_work);

	ret = request_threaded_irq(irq, NULL, certify_cover_detect,
		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
		"certify_cover", ddata);
	if (ret < 0) {
		pr_err("keys: failed to certify about request flip cover irq %d gpio %d\n",
			irq, ddata->pdata->gpio_certify_cover);
	} else {
		pr_info("%s : success\n", __func__);
	}
}

#ifdef CONFIG_OF
static struct hall_platform_data *of_certify_hall_data_parsing_dt(
		struct device *dev)
{
	struct device_node *np_certify_hall;
	struct hall_platform_data *pdata;
	int gpio;
	enum of_gpio_flags flags;
	int ret = 0;

	np_certify_hall = dev->of_node;
	if (np_certify_hall == NULL) {
		pr_err("%s : error to get dt node\n", __func__);
		ret = -EINVAL;
		goto err_out;
	}

	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata) {
		ret = -ENOMEM;
		goto err_out;
	}

	gpio = of_get_named_gpio_flags(np_certify_hall,
			"certify_hall,gpio_certify_cover", 0, &flags);
	if (gpio < 0) {
		pr_err("%s: fail to get certify_cover\n", __func__);
		ret = -EINVAL;
		goto err_out;
	}
	pdata->gpio_certify_cover = gpio;

	gpio = gpio_to_irq(gpio);
	if (gpio < 0) {
		pr_err("%s: fail to return irq corresponding gpio\n", __func__);
		ret = -EINVAL;
		goto err_out;
	}
	pdata->irq_certify_cover = gpio;

	return pdata;
err_out:
	return ERR_PTR(ret);
}
#endif

static int certify_hall_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct certify_hall_drvdata *ddata;
	struct hall_platform_data *pdata = pdev->dev.platform_data;
	struct input_dev *input;
	int error;
	int wakeup = 0;

	ddata = kzalloc(sizeof(struct certify_hall_drvdata), GFP_KERNEL);
	if (!ddata)
		return -ENOMEM;

#ifdef CONFIG_OF
	if (!pdata) {
		pdata = of_certify_hall_data_parsing_dt(dev);
		if (IS_ERR(pdata)) {
			pr_info("%s : fail to get the dt (HALL)\n", __func__);
			error = -ENODEV;
			goto fail1;
		}
	}
#endif

	input = input_allocate_device();
	if (!input) {
		dev_err(dev, "failed to allocate state\n");
		error = -ENOMEM;
		goto fail1;
	}

	ddata->input = input;

	wake_lock_init(&ddata->certify_wake_lock, WAKE_LOCK_SUSPEND,
		"flip wake lock");

	ddata->pdata = pdata;
	platform_set_drvdata(pdev, ddata);
	input_set_drvdata(input, ddata);

	input->name = "certify_hall";
	input->phys = "certify_hall";
	input->dev.parent = &pdev->dev;

	input->evbit[0] |= BIT_MASK(EV_SW);

	ddata->event_val = SW_CERTIFYHALL;

	input_set_capability(input, EV_SW, ddata->event_val);

	input->open = certify_hall_open;
	input->close = certify_hall_close;

	/* Enable auto repeat feature of Linux input subsystem */
	__set_bit(EV_REP, input->evbit);

	init_certify_hall_ic_irq(input);

#if defined(CONFIG_HALL_NEW_NODE)
	error = sysfs_create_group(&hall_ic->kobj, &certify_hall_attr_group);
#else
	error = sysfs_create_group(&sec_key->kobj, &certify_hall_attr_group);
#endif
	if (error) {
		dev_err(dev, "Unable to export keys/switches, error: %d\n",
			error);
		goto fail2;
	}

	error = input_register_device(input);
	if (error) {
		dev_err(dev, "Unable to register input device, error: %d\n",
			error);
		goto fail3;
	}

	device_init_wakeup(&pdev->dev, wakeup);

	return 0;

 fail3:
	sysfs_remove_group(&pdev->dev.kobj, &certify_hall_attr_group);
 fail2:
	platform_set_drvdata(pdev, NULL);
	wake_lock_destroy(&ddata->certify_wake_lock);
	input_free_device(input);
 fail1:
	kfree(ddata);

	return error;
}

static int certify_hall_remove(struct platform_device *pdev)
{
	struct certify_hall_drvdata *ddata = platform_get_drvdata(pdev);
	struct input_dev *input = ddata->input;

	pr_info("%s start\n", __func__);
	sysfs_remove_group(&pdev->dev.kobj, &certify_hall_attr_group);

	device_init_wakeup(&pdev->dev, 0);

	input_unregister_device(input);

	wake_lock_destroy(&ddata->certify_wake_lock);

	kfree(ddata);

	return 0;
}

#if defined(CONFIG_OF)
static const struct of_device_id hall_dt_ids[] = {
	{ .compatible = "certify_hall" },
	{ },
};
MODULE_DEVICE_TABLE(of, hall_dt_ids);
#endif /* CONFIG_OF */

#ifdef CONFIG_PM_SLEEP
static int certify_hall_suspend(struct device *dev)
{
	struct certify_hall_drvdata *ddata = dev_get_drvdata(dev);
	struct input_dev *input = ddata->input;
	bool status;

	pr_info("%s start\n", __func__);
	status = !gpio_get_value(ddata->pdata->gpio_certify_cover);
	pr_info("[keys] %s certify_status : %d (%s)\n", __func__, status,
			status ? "attach" : "detach");

	/*
	 * need to be change
	 * Without below one line, it is not able to get the irq
	 * during freezing
	 */
	enable_irq_wake(ddata->pdata->irq_certify_cover);

	if (device_may_wakeup(dev)) {
		enable_irq_wake(ddata->pdata->irq_certify_cover);
	} else {
		mutex_lock(&input->mutex);
		if (input->users)
			certify_hall_close(input);
		mutex_unlock(&input->mutex);
	}

	return 0;
}

static int certify_hall_resume(struct device *dev)
{
	struct certify_hall_drvdata *ddata = dev_get_drvdata(dev);
	struct input_dev *input = ddata->input;
	bool status;

	pr_info("%s start\n", __func__);
	status = !gpio_get_value(ddata->pdata->gpio_certify_cover);
	pr_info("[keys] %s certify_status : %d (%s)\n", __func__, status,
			status ? "attach" : "detach");
	input_sync(input);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(hall_pm_ops, certify_hall_suspend,
		certify_hall_resume);

static struct platform_driver certify_hall_device_driver = {
	.probe		= certify_hall_probe,
	.remove		= certify_hall_remove,
	.driver		= {
		.name	= "certify_hall",
		.owner	= THIS_MODULE,
		.pm	= &hall_pm_ops,
#if defined(CONFIG_OF)
		.of_match_table	= hall_dt_ids,
#endif /* CONFIG_OF */
	}
};

static int __init certify_hall_init(void)
{
	pr_info("%s start\n", __func__);
	return platform_driver_register(&certify_hall_device_driver);
}

static void __exit certify_hall_exit(void)
{
	pr_info("%s start\n", __func__);
	platform_driver_unregister(&certify_hall_device_driver);
}

late_initcall(certify_hall_init);
module_exit(certify_hall_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Insun Choi <insun77.choi@samsung.com>");
MODULE_DESCRIPTION("Hall IC driver for GPIOs");
MODULE_ALIAS("platform:gpio-keys");