drivers/thermal/int340x_thermal/acpi_thermal_rel.c - kernel/quantenna - Git at Google

 /* acpi_thermal_rel.c driver for exporting ACPI thermal relationship
  *
  * Copyright (c) 2014 Intel Corp
  *
  * 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.
  *
  */

 /*
  * Two functionalities included:
  * 1. Export _TRT, _ART, via misc device interface to the userspace.
  * 2. Provide parsing result to kernel drivers
  *
  */
 #include <linux/init.h>
 #include <linux/export.h>
 #include <linux/module.h>
 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/acpi.h>
 #include <linux/uaccess.h>
 #include <linux/miscdevice.h>
 #include "acpi_thermal_rel.h"

 static acpi_handle acpi_thermal_rel_handle;
 static DEFINE_SPINLOCK(acpi_thermal_rel_chrdev_lock);
 static int acpi_thermal_rel_chrdev_count;	/* #times opened */
 static int acpi_thermal_rel_chrdev_exclu;	/* already open exclusive? */

 static int acpi_thermal_rel_open(struct inode *inode, struct file *file)
 {
 	spin_lock(&acpi_thermal_rel_chrdev_lock);
 	if (acpi_thermal_rel_chrdev_exclu ||
 	    (acpi_thermal_rel_chrdev_count && (file->f_flags & O_EXCL))) {
 		spin_unlock(&acpi_thermal_rel_chrdev_lock);
 		return -EBUSY;
 	}

 	if (file->f_flags & O_EXCL)
 		acpi_thermal_rel_chrdev_exclu = 1;
 	acpi_thermal_rel_chrdev_count++;

 	spin_unlock(&acpi_thermal_rel_chrdev_lock);

 	return nonseekable_open(inode, file);
 }

 static int acpi_thermal_rel_release(struct inode *inode, struct file *file)
 {
 	spin_lock(&acpi_thermal_rel_chrdev_lock);
 	acpi_thermal_rel_chrdev_count--;
 	acpi_thermal_rel_chrdev_exclu = 0;
 	spin_unlock(&acpi_thermal_rel_chrdev_lock);

 	return 0;
 }

 /**
  * acpi_parse_trt - Thermal Relationship Table _TRT for passive cooling
  *
  * @handle: ACPI handle of the device contains _TRT
  * @art_count: the number of valid entries resulted from parsing _TRT
  * @artp: pointer to pointer of array of art entries in parsing result
  * @create_dev: whether to create platform devices for target and source
  *
  */
 int acpi_parse_trt(acpi_handle handle, int *trt_count, struct trt **trtp,
 		bool create_dev)
 {
 	acpi_status status;
 	int result = 0;
 	int i;
 	int nr_bad_entries = 0;
 	struct trt *trts;
 	struct acpi_device *adev;
 	union acpi_object *p;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct acpi_buffer element = { 0, NULL };
 	struct acpi_buffer trt_format = { sizeof("RRNNNNNN"), "RRNNNNNN" };

 	if (!acpi_has_method(handle, "_TRT"))
 		return -ENODEV;

 	status = acpi_evaluate_object(handle, "_TRT", NULL, &buffer);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;

 	p = buffer.pointer;
 	if (!p || (p->type != ACPI_TYPE_PACKAGE)) {
 		pr_err("Invalid _TRT data\n");
 		result = -EFAULT;
 		goto end;
 	}

 	*trt_count = p->package.count;
 	trts = kzalloc(*trt_count * sizeof(struct trt), GFP_KERNEL);
 	if (!trts) {
 		result = -ENOMEM;
 		goto end;
 	}

 	for (i = 0; i < *trt_count; i++) {
 		struct trt *trt = &trts[i - nr_bad_entries];

 		element.length = sizeof(struct trt);
 		element.pointer = trt;

 		status = acpi_extract_package(&(p->package.elements[i]),
 					      &trt_format, &element);
 		if (ACPI_FAILURE(status)) {
 			nr_bad_entries++;
 			pr_warn("_TRT package %d is invalid, ignored\n", i);
 			continue;
 		}
 		if (!create_dev)
 			continue;

 		result = acpi_bus_get_device(trt->source, &adev);
 		if (result)
 			pr_warn("Failed to get source ACPI device\n");

 		result = acpi_bus_get_device(trt->target, &adev);
 		if (result)
 			pr_warn("Failed to get target ACPI device\n");
 	}

 	result = 0;

 	*trtp = trts;
 	/* don't count bad entries */
 	*trt_count -= nr_bad_entries;
 end:
 	kfree(buffer.pointer);
 	return result;
 }
 EXPORT_SYMBOL(acpi_parse_trt);

 /**
  * acpi_parse_art - Parse Active Relationship Table _ART
  *
  * @handle: ACPI handle of the device contains _ART
  * @art_count: the number of valid entries resulted from parsing _ART
  * @artp: pointer to pointer of array of art entries in parsing result
  * @create_dev: whether to create platform devices for target and source
  *
  */
 int acpi_parse_art(acpi_handle handle, int *art_count, struct art **artp,
 		bool create_dev)
 {
 	acpi_status status;
 	int result = 0;
 	int i;
 	int nr_bad_entries = 0;
 	struct art *arts;
 	struct acpi_device *adev;
 	union acpi_object *p;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct acpi_buffer element = { 0, NULL };
 	struct acpi_buffer art_format =	{
 		sizeof("RRNNNNNNNNNNN"), "RRNNNNNNNNNNN" };

 	if (!acpi_has_method(handle, "_ART"))
 		return -ENODEV;

 	status = acpi_evaluate_object(handle, "_ART", NULL, &buffer);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;

 	p = buffer.pointer;
 	if (!p || (p->type != ACPI_TYPE_PACKAGE)) {
 		pr_err("Invalid _ART data\n");
 		result = -EFAULT;
 		goto end;
 	}

 	/* ignore p->package.elements[0], as this is _ART Revision field */
 	*art_count = p->package.count - 1;
 	arts = kzalloc(*art_count * sizeof(struct art), GFP_KERNEL);
 	if (!arts) {
 		result = -ENOMEM;
 		goto end;
 	}

 	for (i = 0; i < *art_count; i++) {
 		struct art *art = &arts[i - nr_bad_entries];

 		element.length = sizeof(struct art);
 		element.pointer = art;

 		status = acpi_extract_package(&(p->package.elements[i + 1]),
 					      &art_format, &element);
 		if (ACPI_FAILURE(status)) {
 			pr_warn("_ART package %d is invalid, ignored", i);
 			nr_bad_entries++;
 			continue;
 		}
 		if (!create_dev)
 			continue;

 		if (art->source) {
 			result = acpi_bus_get_device(art->source, &adev);
 			if (result)
 				pr_warn("Failed to get source ACPI device\n");
 		}
 		if (art->target) {
 			result = acpi_bus_get_device(art->target, &adev);
 			if (result)
 				pr_warn("Failed to get source ACPI device\n");
 		}
 	}

 	*artp = arts;
 	/* don't count bad entries */
 	*art_count -= nr_bad_entries;
 end:
 	kfree(buffer.pointer);
 	return result;
 }
 EXPORT_SYMBOL(acpi_parse_art);


 /* get device name from acpi handle */
 static void get_single_name(acpi_handle handle, char *name)
 {
 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};

 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer)))
 		pr_warn("Failed get name from handle\n");
 	else {
 		memcpy(name, buffer.pointer, ACPI_NAME_SIZE);
 		kfree(buffer.pointer);
 	}
 }

 static int fill_art(char __user *ubuf)
 {
 	int i;
 	int ret;
 	int count;
 	int art_len;
 	struct art *arts = NULL;
 	union art_object *art_user;

 	ret = acpi_parse_art(acpi_thermal_rel_handle, &count, &arts, false);
 	if (ret)
 		goto free_art;
 	art_len = count * sizeof(union art_object);
 	art_user = kzalloc(art_len, GFP_KERNEL);
 	if (!art_user) {
 		ret = -ENOMEM;
 		goto free_art;
 	}
 	/* now fill in user art data */
 	for (i = 0; i < count; i++) {
 		/* userspace art needs device name instead of acpi reference */
 		get_single_name(arts[i].source, art_user[i].source_device);
 		get_single_name(arts[i].target, art_user[i].target_device);
 		/* copy the rest int data in addition to source and target */
 		memcpy(&art_user[i].weight, &arts[i].weight,
 			sizeof(u64) * (ACPI_NR_ART_ELEMENTS - 2));
 	}

 	if (copy_to_user(ubuf, art_user, art_len))
 		ret = -EFAULT;
 	kfree(art_user);
 free_art:
 	kfree(arts);
 	return ret;
 }

 static int fill_trt(char __user *ubuf)
 {
 	int i;
 	int ret;
 	int count;
 	int trt_len;
 	struct trt *trts = NULL;
 	union trt_object *trt_user;

 	ret = acpi_parse_trt(acpi_thermal_rel_handle, &count, &trts, false);
 	if (ret)
 		goto free_trt;
 	trt_len = count * sizeof(union trt_object);
 	trt_user = kzalloc(trt_len, GFP_KERNEL);
 	if (!trt_user) {
 		ret = -ENOMEM;
 		goto free_trt;
 	}
 	/* now fill in user trt data */
 	for (i = 0; i < count; i++) {
 		/* userspace trt needs device name instead of acpi reference */
 		get_single_name(trts[i].source, trt_user[i].source_device);
 		get_single_name(trts[i].target, trt_user[i].target_device);
 		trt_user[i].sample_period = trts[i].sample_period;
 		trt_user[i].influence = trts[i].influence;
 	}

 	if (copy_to_user(ubuf, trt_user, trt_len))
 		ret = -EFAULT;
 	kfree(trt_user);
 free_trt:
 	kfree(trts);
 	return ret;
 }

 static long acpi_thermal_rel_ioctl(struct file *f, unsigned int cmd,
 				   unsigned long __arg)
 {
 	int ret = 0;
 	unsigned long length = 0;
 	int count = 0;
 	char __user *arg = (void __user *)__arg;
 	struct trt *trts = NULL;
 	struct art *arts = NULL;

 	switch (cmd) {
 	case ACPI_THERMAL_GET_TRT_COUNT:
 		ret = acpi_parse_trt(acpi_thermal_rel_handle, &count,
 				&trts, false);
 		kfree(trts);
 		if (!ret)
 			return put_user(count, (unsigned long __user *)__arg);
 		return ret;
 	case ACPI_THERMAL_GET_TRT_LEN:
 		ret = acpi_parse_trt(acpi_thermal_rel_handle, &count,
 				&trts, false);
 		kfree(trts);
 		length = count * sizeof(union trt_object);
 		if (!ret)
 			return put_user(length, (unsigned long __user *)__arg);
 		return ret;
 	case ACPI_THERMAL_GET_TRT:
 		return fill_trt(arg);
 	case ACPI_THERMAL_GET_ART_COUNT:
 		ret = acpi_parse_art(acpi_thermal_rel_handle, &count,
 				&arts, false);
 		kfree(arts);
 		if (!ret)
 			return put_user(count, (unsigned long __user *)__arg);
 		return ret;
 	case ACPI_THERMAL_GET_ART_LEN:
 		ret = acpi_parse_art(acpi_thermal_rel_handle, &count,
 				&arts, false);
 		kfree(arts);
 		length = count * sizeof(union art_object);
 		if (!ret)
 			return put_user(length, (unsigned long __user *)__arg);
 		return ret;

 	case ACPI_THERMAL_GET_ART:
 		return fill_art(arg);

 	default:
 		return -ENOTTY;
 	}
 }

 static const struct file_operations acpi_thermal_rel_fops = {
 	.owner		= THIS_MODULE,
 	.open		= acpi_thermal_rel_open,
 	.release	= acpi_thermal_rel_release,
 	.unlocked_ioctl	= acpi_thermal_rel_ioctl,
 	.llseek		= no_llseek,
 };

 static struct miscdevice acpi_thermal_rel_misc_device = {
 	.minor	= MISC_DYNAMIC_MINOR,
 	"acpi_thermal_rel",
 	&acpi_thermal_rel_fops
 };

 int acpi_thermal_rel_misc_device_add(acpi_handle handle)
 {
 	acpi_thermal_rel_handle = handle;

 	return misc_register(&acpi_thermal_rel_misc_device);
 }
 EXPORT_SYMBOL(acpi_thermal_rel_misc_device_add);

 int acpi_thermal_rel_misc_device_remove(acpi_handle handle)
 {
 	misc_deregister(&acpi_thermal_rel_misc_device);

 	return 0;
 }
 EXPORT_SYMBOL(acpi_thermal_rel_misc_device_remove);

 MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
 MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com");
 MODULE_DESCRIPTION("Intel acpi thermal rel misc dev driver");
 MODULE_LICENSE("GPL v2");
	/* acpi_thermal_rel.c driver for exporting ACPI thermal relationship
	*
	* Copyright (c) 2014 Intel Corp
	*
	* 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.
	*
	*/

	/*
	* Two functionalities included:
	* 1. Export _TRT, _ART, via misc device interface to the userspace.
	* 2. Provide parsing result to kernel drivers
	*
	*/
	#include <linux/init.h>
	#include <linux/export.h>
	#include <linux/module.h>
	#include <linux/device.h>
	#include <linux/platform_device.h>
	#include <linux/io.h>
	#include <linux/acpi.h>
	#include <linux/uaccess.h>
	#include <linux/miscdevice.h>
	#include "acpi_thermal_rel.h"

	static acpi_handle acpi_thermal_rel_handle;
	static DEFINE_SPINLOCK(acpi_thermal_rel_chrdev_lock);
	static int acpi_thermal_rel_chrdev_count; /* #times opened */
	static int acpi_thermal_rel_chrdev_exclu; /* already open exclusive? */

	static int acpi_thermal_rel_open(struct inode inode, struct file file)
	{
	spin_lock(&acpi_thermal_rel_chrdev_lock);
	if (acpi_thermal_rel_chrdev_exclu \|\|
	(acpi_thermal_rel_chrdev_count && (file->f_flags & O_EXCL))) {
	spin_unlock(&acpi_thermal_rel_chrdev_lock);
	return -EBUSY;
	}

	if (file->f_flags & O_EXCL)
	acpi_thermal_rel_chrdev_exclu = 1;
	acpi_thermal_rel_chrdev_count++;

	spin_unlock(&acpi_thermal_rel_chrdev_lock);

	return nonseekable_open(inode, file);
	}

	static int acpi_thermal_rel_release(struct inode inode, struct file file)
	{
	spin_lock(&acpi_thermal_rel_chrdev_lock);
	acpi_thermal_rel_chrdev_count--;
	acpi_thermal_rel_chrdev_exclu = 0;
	spin_unlock(&acpi_thermal_rel_chrdev_lock);

	return 0;
	}

	/**
	* acpi_parse_trt - Thermal Relationship Table _TRT for passive cooling
	*
	* @handle: ACPI handle of the device contains _TRT
	* @art_count: the number of valid entries resulted from parsing _TRT
	* @artp: pointer to pointer of array of art entries in parsing result
	* @create_dev: whether to create platform devices for target and source
	*
	*/
	int acpi_parse_trt(acpi_handle handle, int trt_count, struct trt *trtp,
	bool create_dev)
	{
	acpi_status status;
	int result = 0;
	int i;
	int nr_bad_entries = 0;
	struct trt *trts;
	struct acpi_device *adev;
	union acpi_object *p;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_buffer element = { 0, NULL };
	struct acpi_buffer trt_format = { sizeof("RRNNNNNN"), "RRNNNNNN" };

	if (!acpi_has_method(handle, "_TRT"))
	return -ENODEV;

	status = acpi_evaluate_object(handle, "_TRT", NULL, &buffer);
	if (ACPI_FAILURE(status))
	return -ENODEV;

	p = buffer.pointer;
	if (!p \|\| (p->type != ACPI_TYPE_PACKAGE)) {
	pr_err("Invalid _TRT data\n");
	result = -EFAULT;
	goto end;
	}

	*trt_count = p->package.count;
	trts = kzalloc(trt_count sizeof(struct trt), GFP_KERNEL);
	if (!trts) {
	result = -ENOMEM;
	goto end;
	}

	for (i = 0; i < *trt_count; i++) {
	struct trt *trt = &trts[i - nr_bad_entries];

	element.length = sizeof(struct trt);
	element.pointer = trt;

	status = acpi_extract_package(&(p->package.elements[i]),
	&trt_format, &element);
	if (ACPI_FAILURE(status)) {
	nr_bad_entries++;
	pr_warn("_TRT package %d is invalid, ignored\n", i);
	continue;
	}
	if (!create_dev)
	continue;

	result = acpi_bus_get_device(trt->source, &adev);
	if (result)
	pr_warn("Failed to get source ACPI device\n");

	result = acpi_bus_get_device(trt->target, &adev);
	if (result)
	pr_warn("Failed to get target ACPI device\n");
	}

	result = 0;

	*trtp = trts;
	/* don't count bad entries */
	*trt_count -= nr_bad_entries;
	end:
	kfree(buffer.pointer);
	return result;
	}
	EXPORT_SYMBOL(acpi_parse_trt);

	/**
	* acpi_parse_art - Parse Active Relationship Table _ART
	*
	* @handle: ACPI handle of the device contains _ART
	* @art_count: the number of valid entries resulted from parsing _ART
	* @artp: pointer to pointer of array of art entries in parsing result
	* @create_dev: whether to create platform devices for target and source
	*
	*/
	int acpi_parse_art(acpi_handle handle, int art_count, struct art *artp,
	bool create_dev)
	{
	acpi_status status;
	int result = 0;
	int i;
	int nr_bad_entries = 0;
	struct art *arts;
	struct acpi_device *adev;
	union acpi_object *p;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_buffer element = { 0, NULL };
	struct acpi_buffer art_format = {
	sizeof("RRNNNNNNNNNNN"), "RRNNNNNNNNNNN" };

	if (!acpi_has_method(handle, "_ART"))
	return -ENODEV;

	status = acpi_evaluate_object(handle, "_ART", NULL, &buffer);
	if (ACPI_FAILURE(status))
	return -ENODEV;

	p = buffer.pointer;
	if (!p \|\| (p->type != ACPI_TYPE_PACKAGE)) {
	pr_err("Invalid _ART data\n");
	result = -EFAULT;
	goto end;
	}

	/* ignore p->package.elements[0], as this is _ART Revision field */
	*art_count = p->package.count - 1;
	arts = kzalloc(art_count sizeof(struct art), GFP_KERNEL);
	if (!arts) {
	result = -ENOMEM;
	goto end;
	}

	for (i = 0; i < *art_count; i++) {
	struct art *art = &arts[i - nr_bad_entries];

	element.length = sizeof(struct art);
	element.pointer = art;

	status = acpi_extract_package(&(p->package.elements[i + 1]),
	&art_format, &element);
	if (ACPI_FAILURE(status)) {
	pr_warn("_ART package %d is invalid, ignored", i);
	nr_bad_entries++;
	continue;
	}
	if (!create_dev)
	continue;

	if (art->source) {
	result = acpi_bus_get_device(art->source, &adev);
	if (result)
	pr_warn("Failed to get source ACPI device\n");
	}
	if (art->target) {
	result = acpi_bus_get_device(art->target, &adev);
	if (result)
	pr_warn("Failed to get source ACPI device\n");
	}
	}

	*artp = arts;
	/* don't count bad entries */
	*art_count -= nr_bad_entries;
	end:
	kfree(buffer.pointer);
	return result;
	}
	EXPORT_SYMBOL(acpi_parse_art);


	/* get device name from acpi handle */
	static void get_single_name(acpi_handle handle, char *name)
	{
	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};

	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer)))
	pr_warn("Failed get name from handle\n");
	else {
	memcpy(name, buffer.pointer, ACPI_NAME_SIZE);
	kfree(buffer.pointer);
	}
	}

	static int fill_art(char __user *ubuf)
	{
	int i;
	int ret;
	int count;
	int art_len;
	struct art *arts = NULL;
	union art_object *art_user;

	ret = acpi_parse_art(acpi_thermal_rel_handle, &count, &arts, false);
	if (ret)
	goto free_art;
	art_len = count * sizeof(union art_object);
	art_user = kzalloc(art_len, GFP_KERNEL);
	if (!art_user) {
	ret = -ENOMEM;
	goto free_art;
	}
	/* now fill in user art data */
	for (i = 0; i < count; i++) {
	/* userspace art needs device name instead of acpi reference */
	get_single_name(arts[i].source, art_user[i].source_device);
	get_single_name(arts[i].target, art_user[i].target_device);
	/* copy the rest int data in addition to source and target */
	memcpy(&art_user[i].weight, &arts[i].weight,
	sizeof(u64) * (ACPI_NR_ART_ELEMENTS - 2));
	}

	if (copy_to_user(ubuf, art_user, art_len))
	ret = -EFAULT;
	kfree(art_user);
	free_art:
	kfree(arts);
	return ret;
	}

	static int fill_trt(char __user *ubuf)
	{
	int i;
	int ret;
	int count;
	int trt_len;
	struct trt *trts = NULL;
	union trt_object *trt_user;

	ret = acpi_parse_trt(acpi_thermal_rel_handle, &count, &trts, false);
	if (ret)
	goto free_trt;
	trt_len = count * sizeof(union trt_object);
	trt_user = kzalloc(trt_len, GFP_KERNEL);
	if (!trt_user) {
	ret = -ENOMEM;
	goto free_trt;
	}
	/* now fill in user trt data */
	for (i = 0; i < count; i++) {
	/* userspace trt needs device name instead of acpi reference */
	get_single_name(trts[i].source, trt_user[i].source_device);
	get_single_name(trts[i].target, trt_user[i].target_device);
	trt_user[i].sample_period = trts[i].sample_period;
	trt_user[i].influence = trts[i].influence;
	}

	if (copy_to_user(ubuf, trt_user, trt_len))
	ret = -EFAULT;
	kfree(trt_user);
	free_trt:
	kfree(trts);
	return ret;
	}

	static long acpi_thermal_rel_ioctl(struct file *f, unsigned int cmd,
	unsigned long __arg)
	{
	int ret = 0;
	unsigned long length = 0;
	int count = 0;
	char __user arg = (void __user )__arg;
	struct trt *trts = NULL;
	struct art *arts = NULL;

	switch (cmd) {
	case ACPI_THERMAL_GET_TRT_COUNT:
	ret = acpi_parse_trt(acpi_thermal_rel_handle, &count,
	&trts, false);
	kfree(trts);
	if (!ret)
	return put_user(count, (unsigned long __user *)__arg);
	return ret;
	case ACPI_THERMAL_GET_TRT_LEN:
	ret = acpi_parse_trt(acpi_thermal_rel_handle, &count,
	&trts, false);
	kfree(trts);
	length = count * sizeof(union trt_object);
	if (!ret)
	return put_user(length, (unsigned long __user *)__arg);
	return ret;
	case ACPI_THERMAL_GET_TRT:
	return fill_trt(arg);
	case ACPI_THERMAL_GET_ART_COUNT:
	ret = acpi_parse_art(acpi_thermal_rel_handle, &count,
	&arts, false);
	kfree(arts);
	if (!ret)
	return put_user(count, (unsigned long __user *)__arg);
	return ret;
	case ACPI_THERMAL_GET_ART_LEN:
	ret = acpi_parse_art(acpi_thermal_rel_handle, &count,
	&arts, false);
	kfree(arts);
	length = count * sizeof(union art_object);
	if (!ret)
	return put_user(length, (unsigned long __user *)__arg);
	return ret;

	case ACPI_THERMAL_GET_ART:
	return fill_art(arg);

	default:
	return -ENOTTY;
	}
	}

	static const struct file_operations acpi_thermal_rel_fops = {
	.owner = THIS_MODULE,
	.open = acpi_thermal_rel_open,
	.release = acpi_thermal_rel_release,
	.unlocked_ioctl = acpi_thermal_rel_ioctl,
	.llseek = no_llseek,
	};

	static struct miscdevice acpi_thermal_rel_misc_device = {
	.minor = MISC_DYNAMIC_MINOR,
	"acpi_thermal_rel",
	&acpi_thermal_rel_fops
	};

	int acpi_thermal_rel_misc_device_add(acpi_handle handle)
	{
	acpi_thermal_rel_handle = handle;

	return misc_register(&acpi_thermal_rel_misc_device);
	}
	EXPORT_SYMBOL(acpi_thermal_rel_misc_device_add);

	int acpi_thermal_rel_misc_device_remove(acpi_handle handle)
	{
	misc_deregister(&acpi_thermal_rel_misc_device);

	return 0;
	}
	EXPORT_SYMBOL(acpi_thermal_rel_misc_device_remove);

	MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
	MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com");
	MODULE_DESCRIPTION("Intel acpi thermal rel misc dev driver");
	MODULE_LICENSE("GPL v2");