ac.c revision a6ba5ebef91a59fabd45962e576c02468dbcd33f 
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
53static int acpi_ac_add(struct acpi_device *device);
54static int acpi_ac_remove(struct acpi_device *device, int type);
55static int acpi_ac_open_fs(struct inode *inode, struct file *file);
56
57static struct acpi_driver acpi_ac_driver = {
58	.name = ACPI_AC_DRIVER_NAME,
59	.class = ACPI_AC_CLASS,
60	.ids = ACPI_AC_HID,
61	.ops = {
62		.add = acpi_ac_add,
63		.remove = acpi_ac_remove,
64		},
65};
66
67struct acpi_ac {
68	acpi_handle handle;
69	struct acpi_device * device;
70	unsigned long state;
71};
72
73static struct file_operations acpi_ac_fops = {
74	.open = acpi_ac_open_fs,
75	.read = seq_read,
76	.llseek = seq_lseek,
77	.release = single_release,
78};
79
80/* --------------------------------------------------------------------------
81                               AC Adapter Management
82   -------------------------------------------------------------------------- */
83
84static int acpi_ac_get_state(struct acpi_ac *ac)
85{
86	acpi_status status = AE_OK;
87
88
89	if (!ac)
90		return -EINVAL;
91
92	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
93	if (ACPI_FAILURE(status)) {
94		ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
95		ac->state = ACPI_AC_STATUS_UNKNOWN;
96		return -ENODEV;
97	}
98
99	return 0;
100}
101
102/* --------------------------------------------------------------------------
103                              FS Interface (/proc)
104   -------------------------------------------------------------------------- */
105
106static struct proc_dir_entry *acpi_ac_dir;
107
108static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
109{
110	struct acpi_ac *ac = (struct acpi_ac *)seq->private;
111
112
113	if (!ac)
114		return 0;
115
116	if (acpi_ac_get_state(ac)) {
117		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
118		return 0;
119	}
120
121	seq_puts(seq, "state:                   ");
122	switch (ac->state) {
123	case ACPI_AC_STATUS_OFFLINE:
124		seq_puts(seq, "off-line\n");
125		break;
126	case ACPI_AC_STATUS_ONLINE:
127		seq_puts(seq, "on-line\n");
128		break;
129	default:
130		seq_puts(seq, "unknown\n");
131		break;
132	}
133
134	return 0;
135}
136
137static int acpi_ac_open_fs(struct inode *inode, struct file *file)
138{
139	return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
140}
141
142static int acpi_ac_add_fs(struct acpi_device *device)
143{
144	struct proc_dir_entry *entry = NULL;
145
146
147	if (!acpi_device_dir(device)) {
148		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
149						     acpi_ac_dir);
150		if (!acpi_device_dir(device))
151			return -ENODEV;
152		acpi_device_dir(device)->owner = THIS_MODULE;
153	}
154
155	/* 'state' [R] */
156	entry = create_proc_entry(ACPI_AC_FILE_STATE,
157				  S_IRUGO, acpi_device_dir(device));
158	if (!entry)
159		return -ENODEV;
160	else {
161		entry->proc_fops = &acpi_ac_fops;
162		entry->data = acpi_driver_data(device);
163		entry->owner = THIS_MODULE;
164	}
165
166	return 0;
167}
168
169static int acpi_ac_remove_fs(struct acpi_device *device)
170{
171
172	if (acpi_device_dir(device)) {
173		remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
174
175		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
176		acpi_device_dir(device) = NULL;
177	}
178
179	return 0;
180}
181
182/* --------------------------------------------------------------------------
183                                   Driver Model
184   -------------------------------------------------------------------------- */
185
186static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
187{
188	struct acpi_ac *ac = (struct acpi_ac *)data;
189	struct acpi_device *device = NULL;
190
191
192	if (!ac)
193		return;
194
195	device = ac->device;
196	switch (event) {
197	case ACPI_AC_NOTIFY_STATUS:
198		acpi_ac_get_state(ac);
199		acpi_bus_generate_event(device, event, (u32) ac->state);
200		break;
201	default:
202		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
203				  "Unsupported event [0x%x]\n", event));
204		break;
205	}
206
207	return;
208}
209
210static int acpi_ac_add(struct acpi_device *device)
211{
212	int result = 0;
213	acpi_status status = AE_OK;
214	struct acpi_ac *ac = NULL;
215
216
217	if (!device)
218		return -EINVAL;
219
220	ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
221	if (!ac)
222		return -ENOMEM;
223	memset(ac, 0, sizeof(struct acpi_ac));
224
225	ac->handle = device->handle;
226	ac->device = device;
227	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
228	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
229	acpi_driver_data(device) = ac;
230
231	result = acpi_ac_get_state(ac);
232	if (result)
233		goto end;
234
235	result = acpi_ac_add_fs(device);
236	if (result)
237		goto end;
238
239	status = acpi_install_notify_handler(device->handle,
240					     ACPI_DEVICE_NOTIFY, acpi_ac_notify,
241					     ac);
242	if (ACPI_FAILURE(status)) {
243		result = -ENODEV;
244		goto end;
245	}
246
247	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
248	       acpi_device_name(device), acpi_device_bid(device),
249	       ac->state ? "on-line" : "off-line");
250
251      end:
252	if (result) {
253		acpi_ac_remove_fs(device);
254		kfree(ac);
255	}
256
257	return result;
258}
259
260static int acpi_ac_remove(struct acpi_device *device, int type)
261{
262	acpi_status status = AE_OK;
263	struct acpi_ac *ac = NULL;
264
265
266	if (!device || !acpi_driver_data(device))
267		return -EINVAL;
268
269	ac = (struct acpi_ac *)acpi_driver_data(device);
270
271	status = acpi_remove_notify_handler(device->handle,
272					    ACPI_DEVICE_NOTIFY, acpi_ac_notify);
273
274	acpi_ac_remove_fs(device);
275
276	kfree(ac);
277
278	return 0;
279}
280
281static int __init acpi_ac_init(void)
282{
283	int result = 0;
284
285
286	acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
287	if (!acpi_ac_dir)
288		return -ENODEV;
289	acpi_ac_dir->owner = THIS_MODULE;
290
291	result = acpi_bus_register_driver(&acpi_ac_driver);
292	if (result < 0) {
293		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
294		return -ENODEV;
295	}
296
297	return 0;
298}
299
300static void __exit acpi_ac_exit(void)
301{
302
303	acpi_bus_unregister_driver(&acpi_ac_driver);
304
305	remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
306
307	return;
308}
309
310module_init(acpi_ac_init);
311module_exit(acpi_ac_exit);
312