/*
 * ACPI INT3403 thermal driver
 * Copyright (c) 2013, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/acpi.h>
#include <linux/thermal.h>
#include <linux/platform_device.h>

#define INT3403_TYPE_SENSOR		0x03
#define INT3403_TYPE_CHARGER		0x0B
#define INT3403_TYPE_BATTERY		0x0C
#define INT3403_PERF_CHANGED_EVENT	0x80
#define INT3403_THERMAL_EVENT		0x90

#define DECI_KELVIN_TO_MILLI_CELSIUS(t, off) (((t) - (off)) * 100)
#define KELVIN_OFFSET	2732
#define MILLI_CELSIUS_TO_DECI_KELVIN(t, off) (((t) / 100) + (off))

struct int3403_sensor {
	struct thermal_zone_device *tzone;
	unsigned long *thresholds;
	unsigned long	crit_temp;
	int		crit_trip_id;
	unsigned long	psv_temp;
	int		psv_trip_id;

};

struct int3403_performance_state {
	u64 performance;
	u64 power;
	u64 latency;
	u64 linear;
	u64 control;
	u64 raw_performace;
	char *raw_unit;
	int reserved;
};

struct int3403_cdev {
	struct thermal_cooling_device *cdev;
	unsigned long max_state;
};

struct int3403_priv {
	struct platform_device *pdev;
	struct acpi_device *adev;
	unsigned long long type;
	void *priv;
};

static int sys_get_curr_temp(struct thermal_zone_device *tzone,
				unsigned long *temp)
{
	struct int3403_priv *priv = tzone->devdata;
	struct acpi_device *device = priv->adev;
	unsigned long long tmp;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "_TMP", NULL, &tmp);
	if (ACPI_FAILURE(status))
		return -EIO;

	*temp = DECI_KELVIN_TO_MILLI_CELSIUS(tmp, KELVIN_OFFSET);

	return 0;
}

static int sys_get_trip_hyst(struct thermal_zone_device *tzone,
		int trip, unsigned long *temp)
{
	struct int3403_priv *priv = tzone->devdata;
	struct acpi_device *device = priv->adev;
	unsigned long long hyst;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "GTSH", NULL, &hyst);
	if (ACPI_FAILURE(status))
		return -EIO;

	/*
	 * Thermal hysteresis represents a temperature difference.
	 * Kelvin and Celsius have same degree size. So the
	 * conversion here between tenths of degree Kelvin unit
	 * and Milli-Celsius unit is just to multiply 100.
	 */
	*temp = hyst * 100;

	return 0;
}

static int sys_get_trip_temp(struct thermal_zone_device *tzone,
		int trip, unsigned long *temp)
{
	struct int3403_priv *priv = tzone->devdata;
	struct int3403_sensor *obj = priv->priv;

	if (priv->type != INT3403_TYPE_SENSOR || !obj)
		return -EINVAL;

	if (trip == obj->crit_trip_id)
		*temp = obj->crit_temp;
	else if (trip == obj->psv_trip_id)
		*temp = obj->psv_temp;
	else {
		/*
		 * get_trip_temp is a mandatory callback but
		 * PATx method doesn't return any value, so return
		 * cached value, which was last set from user space
		 */
		*temp = obj->thresholds[trip];
	}

	return 0;
}

static int sys_get_trip_type(struct thermal_zone_device *thermal,
		int trip, enum thermal_trip_type *type)
{
	struct int3403_priv *priv = thermal->devdata;
	struct int3403_sensor *obj = priv->priv;

	/* Mandatory callback, may not mean much here */
	if (trip == obj->crit_trip_id)
		*type = THERMAL_TRIP_CRITICAL;
	else
		*type = THERMAL_TRIP_PASSIVE;

	return 0;
}

int sys_set_trip_temp(struct thermal_zone_device *tzone, int trip,
							unsigned long temp)
{
	struct int3403_priv *priv = tzone->devdata;
	struct acpi_device *device = priv->adev;
	struct int3403_sensor *obj = priv->priv;
	acpi_status status;
	char name[10];
	int ret = 0;

	snprintf(name, sizeof(name), "PAT%d", trip);
	if (acpi_has_method(device->handle, name)) {
		status = acpi_execute_simple_method(device->handle, name,
				MILLI_CELSIUS_TO_DECI_KELVIN(temp,
							KELVIN_OFFSET));
		if (ACPI_FAILURE(status))
			ret = -EIO;
		else
			obj->thresholds[trip] = temp;
	} else {
		ret = -EIO;
		dev_err(&device->dev, "sys_set_trip_temp: method not found\n");
	}

	return ret;
}

static struct thermal_zone_device_ops tzone_ops = {
	.get_temp = sys_get_curr_temp,
	.get_trip_temp = sys_get_trip_temp,
	.get_trip_type = sys_get_trip_type,
	.set_trip_temp = sys_set_trip_temp,
	.get_trip_hyst =  sys_get_trip_hyst,
};

static struct thermal_zone_params int3403_thermal_params = {
	.governor_name = "user_space",
	.no_hwmon = true,
};

static void int3403_notify(acpi_handle handle,
		u32 event, void *data)
{
	struct int3403_priv *priv = data;
	struct int3403_sensor *obj;

	if (!priv)
		return;

	obj = priv->priv;
	if (priv->type != INT3403_TYPE_SENSOR || !obj)
		return;

	switch (event) {
	case INT3403_PERF_CHANGED_EVENT:
		break;
	case INT3403_THERMAL_EVENT:
		thermal_zone_device_update(obj->tzone);
		break;
	default:
		dev_err(&priv->pdev->dev, "Unsupported event [0x%x]\n", event);
		break;
	}
}

static int sys_get_trip_crt(struct acpi_device *device, unsigned long *temp)
{
	unsigned long long crt;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "_CRT", NULL, &crt);
	if (ACPI_FAILURE(status))
		return -EIO;

	*temp = DECI_KELVIN_TO_MILLI_CELSIUS(crt, KELVIN_OFFSET);

	return 0;
}

static int sys_get_trip_psv(struct acpi_device *device, unsigned long *temp)
{
	unsigned long long psv;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "_PSV", NULL, &psv);
	if (ACPI_FAILURE(status))
		return -EIO;

	*temp = DECI_KELVIN_TO_MILLI_CELSIUS(psv, KELVIN_OFFSET);

	return 0;
}

static int int3403_sensor_add(struct int3403_priv *priv)
{
	int result = 0;
	acpi_status status;
	struct int3403_sensor *obj;
	unsigned long long trip_cnt;
	int trip_mask = 0;

	obj = devm_kzalloc(&priv->pdev->dev, sizeof(*obj), GFP_KERNEL);
	if (!obj)
		return -ENOMEM;

	priv->priv = obj;

	status = acpi_evaluate_integer(priv->adev->handle, "PATC", NULL,
						&trip_cnt);
	if (ACPI_FAILURE(status))
		trip_cnt = 0;

	if (trip_cnt) {
		/* We have to cache, thresholds can't be readback */
		obj->thresholds = devm_kzalloc(&priv->pdev->dev,
					sizeof(*obj->thresholds) * trip_cnt,
					GFP_KERNEL);
		if (!obj->thresholds) {
			result = -ENOMEM;
			goto err_free_obj;
		}
		trip_mask = BIT(trip_cnt) - 1;
	}

	obj->psv_trip_id = -1;
	if (!sys_get_trip_psv(priv->adev, &obj->psv_temp))
		obj->psv_trip_id = trip_cnt++;

	obj->crit_trip_id = -1;
	if (!sys_get_trip_crt(priv->adev, &obj->crit_temp))
		obj->crit_trip_id = trip_cnt++;

	obj->tzone = thermal_zone_device_register(acpi_device_bid(priv->adev),
				trip_cnt, trip_mask, priv, &tzone_ops,
				&int3403_thermal_params, 0, 0);
	if (IS_ERR(obj->tzone)) {
		result = PTR_ERR(obj->tzone);
		obj->tzone = NULL;
		goto err_free_obj;
	}

	result = acpi_install_notify_handler(priv->adev->handle,
			ACPI_DEVICE_NOTIFY, int3403_notify,
			(void *)priv);
	if (result)
		goto err_free_obj;

	return 0;

 err_free_obj:
	thermal_zone_device_unregister(obj->tzone);
	return result;
}

static int int3403_sensor_remove(struct int3403_priv *priv)
{
	struct int3403_sensor *obj = priv->priv;

	acpi_remove_notify_handler(priv->adev->handle,
				   ACPI_DEVICE_NOTIFY, int3403_notify);
	thermal_zone_device_unregister(obj->tzone);
	return 0;
}

/* INT3403 Cooling devices */
static int int3403_get_max_state(struct thermal_cooling_device *cdev,
				 unsigned long *state)
{
	struct int3403_priv *priv = cdev->devdata;
	struct int3403_cdev *obj = priv->priv;

	*state = obj->max_state;
	return 0;
}

static int int3403_get_cur_state(struct thermal_cooling_device *cdev,
				 unsigned long *state)
{
	struct int3403_priv *priv = cdev->devdata;
	unsigned long long level;
	acpi_status status;

	status = acpi_evaluate_integer(priv->adev->handle, "PPPC", NULL, &level);
	if (ACPI_SUCCESS(status)) {
		*state = level;
		return 0;
	} else
		return -EINVAL;
}

static int
int3403_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
{
	struct int3403_priv *priv = cdev->devdata;
	acpi_status status;

	status = acpi_execute_simple_method(priv->adev->handle, "SPPC", state);
	if (ACPI_SUCCESS(status))
		return 0;
	else
		return -EINVAL;
}

static const struct thermal_cooling_device_ops int3403_cooling_ops = {
	.get_max_state = int3403_get_max_state,
	.get_cur_state = int3403_get_cur_state,
	.set_cur_state = int3403_set_cur_state,
};

static int int3403_cdev_add(struct int3403_priv *priv)
{
	int result = 0;
	acpi_status status;
	struct int3403_cdev *obj;
	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *p;

	obj = devm_kzalloc(&priv->pdev->dev, sizeof(*obj), GFP_KERNEL);
	if (!obj)
		return -ENOMEM;

	status = acpi_evaluate_object(priv->adev->handle, "PPSS", NULL, &buf);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	p = buf.pointer;
	if (!p || (p->type != ACPI_TYPE_PACKAGE)) {
		printk(KERN_WARNING "Invalid PPSS data\n");
		kfree(buf.pointer);
		return -EFAULT;
	}

	obj->max_state = p->package.count - 1;
	obj->cdev =
		thermal_cooling_device_register(acpi_device_bid(priv->adev),
				priv, &int3403_cooling_ops);
	if (IS_ERR(obj->cdev))
		result = PTR_ERR(obj->cdev);

	priv->priv = obj;

	kfree(buf.pointer);
	/* TODO: add ACPI notification support */

	return result;
}

static int int3403_cdev_remove(struct int3403_priv *priv)
{
	struct int3403_cdev *obj = priv->priv;

	thermal_cooling_device_unregister(obj->cdev);
	return 0;
}

static int int3403_add(struct platform_device *pdev)
{
	struct int3403_priv *priv;
	int result = 0;
	acpi_status status;

	priv = devm_kzalloc(&pdev->dev, sizeof(struct int3403_priv),
			    GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->pdev = pdev;
	priv->adev = ACPI_COMPANION(&(pdev->dev));
	if (!priv->adev) {
		result = -EINVAL;
		goto err;
	}

	status = acpi_evaluate_integer(priv->adev->handle, "PTYP",
				       NULL, &priv->type);
	if (ACPI_FAILURE(status)) {
		result = -EINVAL;
		goto err;
	}

	platform_set_drvdata(pdev, priv);
	switch (priv->type) {
	case INT3403_TYPE_SENSOR:
		result = int3403_sensor_add(priv);
		break;
	case INT3403_TYPE_CHARGER:
	case INT3403_TYPE_BATTERY:
		result = int3403_cdev_add(priv);
		break;
	default:
		result = -EINVAL;
	}

	if (result)
		goto err;
	return result;

err:
	return result;
}

static int int3403_remove(struct platform_device *pdev)
{
	struct int3403_priv *priv = platform_get_drvdata(pdev);

	switch (priv->type) {
	case INT3403_TYPE_SENSOR:
		int3403_sensor_remove(priv);
		break;
	case INT3403_TYPE_CHARGER:
	case INT3403_TYPE_BATTERY:
		int3403_cdev_remove(priv);
		break;
	default:
		break;
	}

	return 0;
}

static const struct acpi_device_id int3403_device_ids[] = {
	{"INT3403", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, int3403_device_ids);

static struct platform_driver int3403_driver = {
	.probe = int3403_add,
	.remove = int3403_remove,
	.driver = {
		.name = "int3403 thermal",
		.acpi_match_table = int3403_device_ids,
	},
};

module_platform_driver(int3403_driver);

MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ACPI INT3403 thermal driver");