ac.c revision 4d8316d5ea4dcf0bf15d8a06d539ed7c99e9cfbe 
1/*
2 *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
3 *
4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
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 <acpi/acpi_bus.h>
33#include <acpi/acpi_drivers.h>
34
35#define ACPI_AC_COMPONENT		0x00020000
36#define ACPI_AC_CLASS			"ac_adapter"
37#define ACPI_AC_HID 			"ACPI0003"
38#define ACPI_AC_DRIVER_NAME		"ACPI AC Adapter Driver"
39#define ACPI_AC_DEVICE_NAME		"AC Adapter"
40#define ACPI_AC_FILE_STATE		"state"
41#define ACPI_AC_NOTIFY_STATUS		0x80
42#define ACPI_AC_STATUS_OFFLINE		0x00
43#define ACPI_AC_STATUS_ONLINE		0x01
44#define ACPI_AC_STATUS_UNKNOWN		0xFF
45
46#define _COMPONENT		ACPI_AC_COMPONENT
47ACPI_MODULE_NAME("acpi_ac")
48
49    MODULE_AUTHOR("Paul Diefenbaugh");
50MODULE_DESCRIPTION(ACPI_AC_DRIVER_NAME);
51MODULE_LICENSE("GPL");
52
53extern struct proc_dir_entry *acpi_lock_ac_dir(void);
54extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
55
56static int acpi_ac_add(struct acpi_device *device);
57static int acpi_ac_remove(struct acpi_device *device, int type);
58static int acpi_ac_open_fs(struct inode *inode, struct file *file);
59
60static struct acpi_driver acpi_ac_driver = {
61	.name = ACPI_AC_DRIVER_NAME,
62	.class = ACPI_AC_CLASS,
63	.ids = ACPI_AC_HID,
64	.ops = {
65		.add = acpi_ac_add,
66		.remove = acpi_ac_remove,
67		},
68};
69
70struct acpi_ac {
71	struct acpi_device * device;
72	unsigned long state;
73};
74
75static const struct file_operations acpi_ac_fops = {
76	.open = acpi_ac_open_fs,
77	.read = seq_read,
78	.llseek = seq_lseek,
79	.release = single_release,
80};
81
82/* --------------------------------------------------------------------------
83                               AC Adapter Management
84   -------------------------------------------------------------------------- */
85
86static int acpi_ac_get_state(struct acpi_ac *ac)
87{
88	acpi_status status = AE_OK;
89
90
91	if (!ac)
92		return -EINVAL;
93
94	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
95	if (ACPI_FAILURE(status)) {
96		ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
97		ac->state = ACPI_AC_STATUS_UNKNOWN;
98		return -ENODEV;
99	}
100
101	return 0;
102}
103
104/* --------------------------------------------------------------------------
105                              FS Interface (/proc)
106   -------------------------------------------------------------------------- */
107
108static struct proc_dir_entry *acpi_ac_dir;
109
110static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
111{
112	struct acpi_ac *ac = (struct acpi_ac *)seq->private;
113
114
115	if (!ac)
116		return 0;
117
118	if (acpi_ac_get_state(ac)) {
119		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
120		return 0;
121	}
122
123	seq_puts(seq, "state:                   ");
124	switch (ac->state) {
125	case ACPI_AC_STATUS_OFFLINE:
126		seq_puts(seq, "off-line\n");
127		break;
128	case ACPI_AC_STATUS_ONLINE:
129		seq_puts(seq, "on-line\n");
130		break;
131	default:
132		seq_puts(seq, "unknown\n");
133		break;
134	}
135
136	return 0;
137}
138
139static int acpi_ac_open_fs(struct inode *inode, struct file *file)
140{
141	return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
142}
143
144static int acpi_ac_add_fs(struct acpi_device *device)
145{
146	struct proc_dir_entry *entry = NULL;
147
148
149	if (!acpi_device_dir(device)) {
150		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
151						     acpi_ac_dir);
152		if (!acpi_device_dir(device))
153			return -ENODEV;
154		acpi_device_dir(device)->owner = THIS_MODULE;
155	}
156
157	/* 'state' [R] */
158	entry = create_proc_entry(ACPI_AC_FILE_STATE,
159				  S_IRUGO, acpi_device_dir(device));
160	if (!entry)
161		return -ENODEV;
162	else {
163		entry->proc_fops = &acpi_ac_fops;
164		entry->data = acpi_driver_data(device);
165		entry->owner = THIS_MODULE;
166	}
167
168	return 0;
169}
170
171static int acpi_ac_remove_fs(struct acpi_device *device)
172{
173
174	if (acpi_device_dir(device)) {
175		remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
176
177		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
178		acpi_device_dir(device) = NULL;
179	}
180
181	return 0;
182}
183
184/* --------------------------------------------------------------------------
185                                   Driver Model
186   -------------------------------------------------------------------------- */
187
188static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
189{
190	struct acpi_ac *ac = (struct acpi_ac *)data;
191	struct acpi_device *device = NULL;
192
193
194	if (!ac)
195		return;
196
197	device = ac->device;
198	switch (event) {
199	case ACPI_AC_NOTIFY_STATUS:
200	case ACPI_NOTIFY_BUS_CHECK:
201	case ACPI_NOTIFY_DEVICE_CHECK:
202		acpi_ac_get_state(ac);
203		acpi_bus_generate_event(device, event, (u32) ac->state);
204		break;
205	default:
206		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
207				  "Unsupported event [0x%x]\n", event));
208		break;
209	}
210
211	return;
212}
213
214static int acpi_ac_add(struct acpi_device *device)
215{
216	int result = 0;
217	acpi_status status = AE_OK;
218	struct acpi_ac *ac = NULL;
219
220
221	if (!device)
222		return -EINVAL;
223
224	ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
225	if (!ac)
226		return -ENOMEM;
227	memset(ac, 0, sizeof(struct acpi_ac));
228
229	ac->device = device;
230	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
231	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
232	acpi_driver_data(device) = ac;
233
234	result = acpi_ac_get_state(ac);
235	if (result)
236		goto end;
237
238	result = acpi_ac_add_fs(device);
239	if (result)
240		goto end;
241
242	status = acpi_install_notify_handler(device->handle,
243					     ACPI_ALL_NOTIFY, acpi_ac_notify,
244					     ac);
245	if (ACPI_FAILURE(status)) {
246		result = -ENODEV;
247		goto end;
248	}
249
250	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
251	       acpi_device_name(device), acpi_device_bid(device),
252	       ac->state ? "on-line" : "off-line");
253
254      end:
255	if (result) {
256		acpi_ac_remove_fs(device);
257		kfree(ac);
258	}
259
260	return result;
261}
262
263static int acpi_ac_remove(struct acpi_device *device, int type)
264{
265	acpi_status status = AE_OK;
266	struct acpi_ac *ac = NULL;
267
268
269	if (!device || !acpi_driver_data(device))
270		return -EINVAL;
271
272	ac = (struct acpi_ac *)acpi_driver_data(device);
273
274	status = acpi_remove_notify_handler(device->handle,
275					    ACPI_ALL_NOTIFY, acpi_ac_notify);
276
277	acpi_ac_remove_fs(device);
278
279	kfree(ac);
280
281	return 0;
282}
283
284static int __init acpi_ac_init(void)
285{
286	int result;
287
288	if (acpi_disabled)
289		return -ENODEV;
290
291	acpi_ac_dir = acpi_lock_ac_dir();
292	if (!acpi_ac_dir)
293		return -ENODEV;
294
295	result = acpi_bus_register_driver(&acpi_ac_driver);
296	if (result < 0) {
297		acpi_unlock_ac_dir(acpi_ac_dir);
298		return -ENODEV;
299	}
300
301	return 0;
302}
303
304static void __exit acpi_ac_exit(void)
305{
306
307	acpi_bus_unregister_driver(&acpi_ac_driver);
308
309	acpi_unlock_ac_dir(acpi_ac_dir);
310
311	return;
312}
313
314module_init(acpi_ac_init);
315module_exit(acpi_ac_exit);
316