[linux.git] / drivers / acpi / fan.c

/*
 *  acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that 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.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/uaccess.h>
#include <linux/thermal.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define ACPI_FAN_CLASS			"fan"
#define ACPI_FAN_FILE_STATE		"state"

#define _COMPONENT		ACPI_FAN_COMPONENT
ACPI_MODULE_NAME("fan");

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI Fan Driver");
MODULE_LICENSE("GPL");

static int acpi_fan_add(struct acpi_device *device);
static int acpi_fan_remove(struct acpi_device *device, int type);
static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
static int acpi_fan_resume(struct acpi_device *device);

static const struct acpi_device_id fan_device_ids[] = {
	{"PNP0C0B", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, fan_device_ids);

static struct acpi_driver acpi_fan_driver = {
	.name = "fan",
	.class = ACPI_FAN_CLASS,
	.ids = fan_device_ids,
	.ops = {
		.add = acpi_fan_add,
		.remove = acpi_fan_remove,
		.suspend = acpi_fan_suspend,
		.resume = acpi_fan_resume,
		},
};

/* thermal cooling device callbacks */
static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
{
	/* ACPI fan device only support two states: ON/OFF */
	return sprintf(buf, "1\n");
}

static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
{
	struct acpi_device *device = cdev->devdata;
	int state;
	int result;

	if (!device)
		return -EINVAL;

	result = acpi_bus_get_power(device->handle, &state);
	if (result)
		return result;

	return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
			 (state == ACPI_STATE_D0 ? "1" : "unknown"));
}

static int
fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
{
	struct acpi_device *device = cdev->devdata;
	int result;

	if (!device || (state != 0 && state != 1))
		return -EINVAL;

	result = acpi_bus_set_power(device->handle,
				state ? ACPI_STATE_D0 : ACPI_STATE_D3);

	return result;
}

static struct thermal_cooling_device_ops fan_cooling_ops = {
	.get_max_state = fan_get_max_state,
	.get_cur_state = fan_get_cur_state,
	.set_cur_state = fan_set_cur_state,
};

/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */
#ifdef CONFIG_ACPI_PROCFS

static struct proc_dir_entry *acpi_fan_dir;

static int acpi_fan_read_state(struct seq_file *seq, void *offset)
{
	struct acpi_device *device = seq->private;
	int state = 0;


	if (device) {
		if (acpi_bus_get_power(device->handle, &state))
			seq_printf(seq, "status:                  ERROR\n");
		else
			seq_printf(seq, "status:                  %s\n",
				   !state ? "on" : "off");
	}
	return 0;
}

static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_fan_read_state, PDE(inode)->data);
}

static ssize_t
acpi_fan_write_state(struct file *file, const char __user * buffer,
		     size_t count, loff_t * ppos)
{
	int result = 0;
	struct seq_file *m = file->private_data;
	struct acpi_device *device = m->private;
	char state_string[3] = { '\0' };

	if (count > sizeof(state_string) - 1)
		return -EINVAL;

	if (copy_from_user(state_string, buffer, count))
		return -EFAULT;

	state_string[count] = '\0';
	if ((state_string[0] < '0') || (state_string[0] > '3'))
		return -EINVAL;
	if (state_string[1] == '\n')
		state_string[1] = '\0';
	if (state_string[1] != '\0')
		return -EINVAL;

	result = acpi_bus_set_power(device->handle,
				    simple_strtoul(state_string, NULL, 0));
	if (result)
		return result;

	return count;
}

static const struct file_operations acpi_fan_state_ops = {
	.open = acpi_fan_state_open_fs,
	.read = seq_read,
	.write = acpi_fan_write_state,
	.llseek = seq_lseek,
	.release = single_release,
	.owner = THIS_MODULE,
};

static int acpi_fan_add_fs(struct acpi_device *device)
{
	struct proc_dir_entry *entry = NULL;


	if (!device)
		return -EINVAL;

	if (!acpi_device_dir(device)) {
		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
						     acpi_fan_dir);
		if (!acpi_device_dir(device))
			return -ENODEV;
		acpi_device_dir(device)->owner = THIS_MODULE;
	}

	/* 'status' [R/W] */
	entry = proc_create_data(ACPI_FAN_FILE_STATE,
				 S_IFREG | S_IRUGO | S_IWUSR,
				 acpi_device_dir(device),
				 &acpi_fan_state_ops,
				 device);
	if (!entry)
		return -ENODEV;
	return 0;
}

static int acpi_fan_remove_fs(struct acpi_device *device)
{

	if (acpi_device_dir(device)) {
		remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
		remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
		acpi_device_dir(device) = NULL;
	}

	return 0;
}
#else
static int acpi_fan_add_fs(struct acpi_device *device)
{
	return 0;
}

static int acpi_fan_remove_fs(struct acpi_device *device)
{
	return 0;
}
#endif
/* --------------------------------------------------------------------------
                                 Driver Interface
   -------------------------------------------------------------------------- */

static int acpi_fan_add(struct acpi_device *device)
{
	int result = 0;
	int state = 0;
	struct thermal_cooling_device *cdev;

	if (!device)
		return -EINVAL;

	strcpy(acpi_device_name(device), "Fan");
	strcpy(acpi_device_class(device), ACPI_FAN_CLASS);

	result = acpi_bus_get_power(device->handle, &state);
	if (result) {
		printk(KERN_ERR PREFIX "Reading power state\n");
		goto end;
	}

	device->flags.force_power_state = 1;
	acpi_bus_set_power(device->handle, state);
	device->flags.force_power_state = 0;

	cdev = thermal_cooling_device_register("Fan", device,
						&fan_cooling_ops);
	if (IS_ERR(cdev)) {
		result = PTR_ERR(cdev);
		goto end;
	}

	dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);

	device->driver_data = cdev;
	result = sysfs_create_link(&device->dev.kobj,
				   &cdev->device.kobj,
				   "thermal_cooling");
	if (result)
		dev_err(&device->dev, "Failed to create sysfs link "
			"'thermal_cooling'\n");

	result = sysfs_create_link(&cdev->device.kobj,
				   &device->dev.kobj,
				   "device");
	if (result)
		dev_err(&device->dev, "Failed to create sysfs link "
			"'device'\n");

	result = acpi_fan_add_fs(device);
	if (result)
		goto end;

	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
	       acpi_device_name(device), acpi_device_bid(device),
	       !device->power.state ? "on" : "off");

      end:
	return result;
}

static int acpi_fan_remove(struct acpi_device *device, int type)
{
	struct thermal_cooling_device *cdev = acpi_driver_data(device);

	if (!device || !cdev)
		return -EINVAL;

	acpi_fan_remove_fs(device);
	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
	sysfs_remove_link(&cdev->device.kobj, "device");
	thermal_cooling_device_unregister(cdev);

	return 0;
}

static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
{
	if (!device)
		return -EINVAL;

	acpi_bus_set_power(device->handle, ACPI_STATE_D0);

	return AE_OK;
}

static int acpi_fan_resume(struct acpi_device *device)
{
	int result = 0;
	int power_state = 0;

	if (!device)
		return -EINVAL;

	result = acpi_bus_get_power(device->handle, &power_state);
	if (result) {
		printk(KERN_ERR PREFIX
				  "Error reading fan power state\n");
		return result;
	}

	device->flags.force_power_state = 1;
	acpi_bus_set_power(device->handle, power_state);
	device->flags.force_power_state = 0;

	return result;
}

static int __init acpi_fan_init(void)
{
	int result = 0;


#ifdef CONFIG_ACPI_PROCFS
	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
	if (!acpi_fan_dir)
		return -ENODEV;
	acpi_fan_dir->owner = THIS_MODULE;
#endif

	result = acpi_bus_register_driver(&acpi_fan_driver);
	if (result < 0) {
		remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
		return -ENODEV;
	}

	return 0;
}

static void __exit acpi_fan_exit(void)
{

	acpi_bus_unregister_driver(&acpi_fan_driver);

	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);

	return;
}

module_init(acpi_fan_init);
module_exit(acpi_fan_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
	3	*
	4	* Copyright (C) 2001, 2002 Andy Grover <[email protected]>
	5	* Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
	6	*
	7	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or (at
	12	* your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful, but
	15	* WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License along
	20	* with this program; if not, write to the Free Software Foundation, Inc.,
	21	* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
	22	*
	23	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	24	*/
	25
	26	#include <linux/kernel.h>
	27	#include <linux/module.h>
	28	#include <linux/init.h>
	29	#include <linux/types.h>
	30	#include <linux/proc_fs.h>
	31	#include <linux/seq_file.h>
	32	#include <asm/uaccess.h>
05a83d97	33	#include <linux/thermal.h>
1da177e4 LT	34	#include <acpi/acpi_bus.h>
	35	#include <acpi/acpi_drivers.h>
	36
1da177e4	37	#define ACPI_FAN_CLASS "fan"
1da177e4	38	#define ACPI_FAN_FILE_STATE "state"
1da177e4 LT	39
1da177e4 LT	40	#define _COMPONENT ACPI_FAN_COMPONENT
f52fd66d	41	ACPI_MODULE_NAME("fan");
1da177e4	42
f52fd66d	43	MODULE_AUTHOR("Paul Diefenbaugh");
7cda93e0	44	MODULE_DESCRIPTION("ACPI Fan Driver");
1da177e4 LT	45	MODULE_LICENSE("GPL");
1da177e4 LT	46
4be44fcd LB	47	static int acpi_fan_add(struct acpi_device *device);
4be44fcd LB	48	static int acpi_fan_remove(struct acpi_device *device, int type);
ec68373c LB	49	static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
ec68373c LB	50	static int acpi_fan_resume(struct acpi_device *device);
1da177e4	51
1ba90e3a TR	52	static const struct acpi_device_id fan_device_ids[] = {
	53	{"PNP0C0B", 0},
	54	{"", 0},
	55	};
	56	MODULE_DEVICE_TABLE(acpi, fan_device_ids);
	57
1da177e4	58	static struct acpi_driver acpi_fan_driver = {
c2b6705b	59	.name = "fan",
4be44fcd	60	.class = ACPI_FAN_CLASS,
1ba90e3a	61	.ids = fan_device_ids,
4be44fcd LB	62	.ops = {
	63	.add = acpi_fan_add,
	64	.remove = acpi_fan_remove,
ec68373c LB	65	.suspend = acpi_fan_suspend,
ec68373c LB	66	.resume = acpi_fan_resume,
4be44fcd	67	},
1da177e4 LT	68	};
1da177e4 LT	69
05a83d97 ZR	70	/* thermal cooling device callbacks */
	71	static int fan_get_max_state(struct thermal_cooling_device cdev, char buf)
	72	{
	73	/* ACPI fan device only support two states: ON/OFF */
	74	return sprintf(buf, "1\n");
	75	}
	76
	77	static int fan_get_cur_state(struct thermal_cooling_device cdev, char buf)
	78	{
	79	struct acpi_device *device = cdev->devdata;
	80	int state;
	81	int result;
	82
	83	if (!device)
	84	return -EINVAL;
	85
	86	result = acpi_bus_get_power(device->handle, &state);
	87	if (result)
	88	return result;
	89
	90	return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
	91	(state == ACPI_STATE_D0 ? "1" : "unknown"));
	92	}
	93
	94	static int
	95	fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
	96	{
	97	struct acpi_device *device = cdev->devdata;
	98	int result;
	99
	100	if (!device \|\| (state != 0 && state != 1))
	101	return -EINVAL;
	102
	103	result = acpi_bus_set_power(device->handle,
	104	state ? ACPI_STATE_D0 : ACPI_STATE_D3);
	105
	106	return result;
	107	}
	108
	109	static struct thermal_cooling_device_ops fan_cooling_ops = {
	110	.get_max_state = fan_get_max_state,
	111	.get_cur_state = fan_get_cur_state,
	112	.set_cur_state = fan_set_cur_state,
	113	};
	114
1da177e4 LT	115	/* --------------------------------------------------------------------------
	116	FS Interface (/proc)
	117	-------------------------------------------------------------------------- */
05a83d97	118	#ifdef CONFIG_ACPI_PROCFS
1da177e4	119
4be44fcd	120	static struct proc_dir_entry *acpi_fan_dir;
1da177e4	121
4be44fcd	122	static int acpi_fan_read_state(struct seq_file seq, void offset)
1da177e4	123	{
968fc5dc	124	struct acpi_device *device = seq->private;
4be44fcd	125	int state = 0;
1da177e4	126
1da177e4	127
968fc5dc AS	128	if (device) {
968fc5dc AS	129	if (acpi_bus_get_power(device->handle, &state))
1da177e4 LT	130	seq_printf(seq, "status: ERROR\n");
	131	else
	132	seq_printf(seq, "status: %s\n",
4be44fcd	133	!state ? "on" : "off");
1da177e4	134	}
d550d98d	135	return 0;
1da177e4 LT	136	}
	137
	138	static int acpi_fan_state_open_fs(struct inode inode, struct file file)
	139	{
	140	return single_open(file, acpi_fan_read_state, PDE(inode)->data);
	141	}
	142
	143	static ssize_t
4be44fcd LB	144	acpi_fan_write_state(struct file file, const char __user buffer,
4be44fcd LB	145	size_t count, loff_t * ppos)
1da177e4	146	{
4be44fcd	147	int result = 0;
50dd0969	148	struct seq_file *m = file->private_data;
968fc5dc	149	struct acpi_device *device = m->private;
6594d87e	150	char state_string[3] = { '\0' };
1da177e4	151
968fc5dc	152	if (count > sizeof(state_string) - 1)
d550d98d	153	return -EINVAL;
4be44fcd	154
1da177e4	155	if (copy_from_user(state_string, buffer, count))
d550d98d	156	return -EFAULT;
4be44fcd	157
1da177e4	158	state_string[count] = '\0';
6594d87e YY	159	if ((state_string[0] < '0') \|\| (state_string[0] > '3'))
	160	return -EINVAL;
	161	if (state_string[1] == '\n')
	162	state_string[1] = '\0';
	163	if (state_string[1] != '\0')
	164	return -EINVAL;
4be44fcd	165
968fc5dc	166	result = acpi_bus_set_power(device->handle,
4be44fcd	167	simple_strtoul(state_string, NULL, 0));
1da177e4	168	if (result)
d550d98d	169	return result;
1da177e4	170
d550d98d	171	return count;
1da177e4 LT	172	}
1da177e4 LT	173
d7508032	174	static const struct file_operations acpi_fan_state_ops = {
4be44fcd LB	175	.open = acpi_fan_state_open_fs,
	176	.read = seq_read,
	177	.write = acpi_fan_write_state,
	178	.llseek = seq_lseek,
	179	.release = single_release,
1da177e4 LT	180	.owner = THIS_MODULE,
	181	};
	182
4be44fcd	183	static int acpi_fan_add_fs(struct acpi_device *device)
1da177e4	184	{
4be44fcd	185	struct proc_dir_entry *entry = NULL;
1da177e4	186
1da177e4 LT	187
1da177e4 LT	188	if (!device)
d550d98d	189	return -EINVAL;
1da177e4 LT	190
	191	if (!acpi_device_dir(device)) {
	192	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
4be44fcd	193	acpi_fan_dir);
1da177e4	194	if (!acpi_device_dir(device))
d550d98d	195	return -ENODEV;
1da177e4 LT	196	acpi_device_dir(device)->owner = THIS_MODULE;
	197	}
	198
	199	/* 'status' [R/W] */
cf7acfab DL	200	entry = proc_create_data(ACPI_FAN_FILE_STATE,
	201	S_IFREG \| S_IRUGO \| S_IWUSR,
	202	acpi_device_dir(device),
	203	&acpi_fan_state_ops,
	204	device);
1da177e4	205	if (!entry)
d550d98d	206	return -ENODEV;
d550d98d	207	return 0;
1da177e4 LT	208	}
1da177e4 LT	209
4be44fcd	210	static int acpi_fan_remove_fs(struct acpi_device *device)
1da177e4	211	{
1da177e4 LT	212
1da177e4 LT	213	if (acpi_device_dir(device)) {
4be44fcd	214	remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
1da177e4 LT	215	remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
	216	acpi_device_dir(device) = NULL;
	217	}
	218
d550d98d	219	return 0;
1da177e4	220	}
05a83d97 ZR	221	#else
	222	static int acpi_fan_add_fs(struct acpi_device *device)
	223	{
	224	return 0;
	225	}
1da177e4	226
05a83d97 ZR	227	static int acpi_fan_remove_fs(struct acpi_device *device)
	228	{
	229	return 0;
	230	}
	231	#endif
1da177e4 LT	232	/* --------------------------------------------------------------------------
	233	Driver Interface
	234	-------------------------------------------------------------------------- */
	235
4be44fcd	236	static int acpi_fan_add(struct acpi_device *device)
1da177e4	237	{
4be44fcd	238	int result = 0;
4be44fcd	239	int state = 0;
05a83d97	240	struct thermal_cooling_device *cdev;
1da177e4 LT	241
1da177e4 LT	242	if (!device)
d550d98d	243	return -EINVAL;
1da177e4	244
c65ade4d	245	strcpy(acpi_device_name(device), "Fan");
1da177e4	246	strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
1da177e4	247
dc8c2b27	248	result = acpi_bus_get_power(device->handle, &state);
1da177e4	249	if (result) {
6468463a	250	printk(KERN_ERR PREFIX "Reading power state\n");
1da177e4 LT	251	goto end;
	252	}
	253
ec68373c LB	254	device->flags.force_power_state = 1;
	255	acpi_bus_set_power(device->handle, state);
	256	device->flags.force_power_state = 0;
	257
05a83d97 ZR	258	cdev = thermal_cooling_device_register("Fan", device,
05a83d97 ZR	259	&fan_cooling_ops);
19b36780 TS	260	if (IS_ERR(cdev)) {
	261	result = PTR_ERR(cdev);
	262	goto end;
	263	}
9030062f	264
fc3a8828	265	dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
9030062f	266
db89b4f0	267	device->driver_data = cdev;
9030062f JL	268	result = sysfs_create_link(&device->dev.kobj,
	269	&cdev->device.kobj,
	270	"thermal_cooling");
	271	if (result)
fc3a8828 GKH	272	dev_err(&device->dev, "Failed to create sysfs link "
fc3a8828 GKH	273	"'thermal_cooling'\n");
9030062f JL	274
	275	result = sysfs_create_link(&cdev->device.kobj,
	276	&device->dev.kobj,
	277	"device");
	278	if (result)
fc3a8828 GKH	279	dev_err(&device->dev, "Failed to create sysfs link "
fc3a8828 GKH	280	"'device'\n");
05a83d97	281
1da177e4 LT	282	result = acpi_fan_add_fs(device);
	283	if (result)
	284	goto end;
	285
	286	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
4be44fcd LB	287	acpi_device_name(device), acpi_device_bid(device),
4be44fcd LB	288	!device->power.state ? "on" : "off");
1da177e4	289
4be44fcd	290	end:
d550d98d	291	return result;
1da177e4 LT	292	}
1da177e4 LT	293
4be44fcd	294	static int acpi_fan_remove(struct acpi_device *device, int type)
1da177e4	295	{
05a83d97 ZR	296	struct thermal_cooling_device *cdev = acpi_driver_data(device);
	297
	298	if (!device \|\| !cdev)
d550d98d	299	return -EINVAL;
1da177e4	300
1da177e4	301	acpi_fan_remove_fs(device);
05a83d97 ZR	302	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
	303	sysfs_remove_link(&cdev->device.kobj, "device");
	304	thermal_cooling_device_unregister(cdev);
1da177e4	305
d550d98d	306	return 0;
1da177e4 LT	307	}
1da177e4 LT	308
ec68373c LB	309	static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
	310	{
	311	if (!device)
	312	return -EINVAL;
	313
	314	acpi_bus_set_power(device->handle, ACPI_STATE_D0);
	315
	316	return AE_OK;
	317	}
	318
	319	static int acpi_fan_resume(struct acpi_device *device)
	320	{
	321	int result = 0;
	322	int power_state = 0;
	323
	324	if (!device)
	325	return -EINVAL;
	326
	327	result = acpi_bus_get_power(device->handle, &power_state);
	328	if (result) {
55ac9a01 LM	329	printk(KERN_ERR PREFIX
55ac9a01 LM	330	"Error reading fan power state\n");
ec68373c LB	331	return result;
	332	}
	333
	334	device->flags.force_power_state = 1;
	335	acpi_bus_set_power(device->handle, power_state);
	336	device->flags.force_power_state = 0;
	337
	338	return result;
	339	}
	340
4be44fcd	341	static int __init acpi_fan_init(void)
1da177e4	342	{
c65ade4d	343	int result = 0;
1da177e4	344
1da177e4	345
3c602840	346	#ifdef CONFIG_ACPI_PROCFS
1da177e4 LT	347	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
1da177e4 LT	348	if (!acpi_fan_dir)
d550d98d	349	return -ENODEV;
1da177e4	350	acpi_fan_dir->owner = THIS_MODULE;
3c602840	351	#endif
1da177e4 LT	352
	353	result = acpi_bus_register_driver(&acpi_fan_driver);
	354	if (result < 0) {
	355	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
d550d98d	356	return -ENODEV;
1da177e4 LT	357	}
1da177e4 LT	358
d550d98d	359	return 0;
1da177e4 LT	360	}
1da177e4 LT	361
4be44fcd	362	static void __exit acpi_fan_exit(void)
1da177e4	363	{
1da177e4 LT	364
	365	acpi_bus_unregister_driver(&acpi_fan_driver);
	366
	367	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
	368
d550d98d	369	return;
1da177e4 LT	370	}
1da177e4 LT	371
1da177e4 LT	372	module_init(acpi_fan_init);
1da177e4 LT	373	module_exit(acpi_fan_exit);