ac.c revision 4be44fcd3bf648b782f4460fd06dfae6c42ded4b 
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	unsigned long state;
70};
71
72static struct file_operations acpi_ac_fops = {
73	.open = acpi_ac_open_fs,
74	.read = seq_read,
75	.llseek = seq_lseek,
76	.release = single_release,
77};
78
79/* --------------------------------------------------------------------------
80                               AC Adapter Management
81   -------------------------------------------------------------------------- */
82
83static int acpi_ac_get_state(struct acpi_ac *ac)
84{
85	acpi_status status = AE_OK;
86
87	ACPI_FUNCTION_TRACE("acpi_ac_get_state");
88
89	if (!ac)
90		return_VALUE(-EINVAL);
91
92	status = acpi_evaluate_integer(ac->handle, "_PSR", NULL, &ac->state);
93	if (ACPI_FAILURE(status)) {
94		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
95				  "Error reading AC Adapter state\n"));
96		ac->state = ACPI_AC_STATUS_UNKNOWN;
97		return_VALUE(-ENODEV);
98	}
99
100	return_VALUE(0);
101}
102
103/* --------------------------------------------------------------------------
104                              FS Interface (/proc)
105   -------------------------------------------------------------------------- */
106
107static struct proc_dir_entry *acpi_ac_dir;
108
109static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
110{
111	struct acpi_ac *ac = (struct acpi_ac *)seq->private;
112
113	ACPI_FUNCTION_TRACE("acpi_ac_seq_show");
114
115	if (!ac)
116		return_VALUE(0);
117
118	if (acpi_ac_get_state(ac)) {
119		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
120		return_VALUE(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_VALUE(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	ACPI_FUNCTION_TRACE("acpi_ac_add_fs");
149
150	if (!acpi_device_dir(device)) {
151		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
152						     acpi_ac_dir);
153		if (!acpi_device_dir(device))
154			return_VALUE(-ENODEV);
155		acpi_device_dir(device)->owner = THIS_MODULE;
156	}
157
158	/* 'state' [R] */
159	entry = create_proc_entry(ACPI_AC_FILE_STATE,
160				  S_IRUGO, acpi_device_dir(device));
161	if (!entry)
162		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
163				  "Unable to create '%s' fs entry\n",
164				  ACPI_AC_FILE_STATE));
165	else {
166		entry->proc_fops = &acpi_ac_fops;
167		entry->data = acpi_driver_data(device);
168		entry->owner = THIS_MODULE;
169	}
170
171	return_VALUE(0);
172}
173
174static int acpi_ac_remove_fs(struct acpi_device *device)
175{
176	ACPI_FUNCTION_TRACE("acpi_ac_remove_fs");
177
178	if (acpi_device_dir(device)) {
179		remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
180
181		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
182		acpi_device_dir(device) = NULL;
183	}
184
185	return_VALUE(0);
186}
187
188/* --------------------------------------------------------------------------
189                                   Driver Model
190   -------------------------------------------------------------------------- */
191
192static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
193{
194	struct acpi_ac *ac = (struct acpi_ac *)data;
195	struct acpi_device *device = NULL;
196
197	ACPI_FUNCTION_TRACE("acpi_ac_notify");
198
199	if (!ac)
200		return_VOID;
201
202	if (acpi_bus_get_device(ac->handle, &device))
203		return_VOID;
204
205	switch (event) {
206	case ACPI_AC_NOTIFY_STATUS:
207		acpi_ac_get_state(ac);
208		acpi_bus_generate_event(device, event, (u32) ac->state);
209		break;
210	default:
211		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
212				  "Unsupported event [0x%x]\n", event));
213		break;
214	}
215
216	return_VOID;
217}
218
219static int acpi_ac_add(struct acpi_device *device)
220{
221	int result = 0;
222	acpi_status status = AE_OK;
223	struct acpi_ac *ac = NULL;
224
225	ACPI_FUNCTION_TRACE("acpi_ac_add");
226
227	if (!device)
228		return_VALUE(-EINVAL);
229
230	ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
231	if (!ac)
232		return_VALUE(-ENOMEM);
233	memset(ac, 0, sizeof(struct acpi_ac));
234
235	ac->handle = device->handle;
236	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
237	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
238	acpi_driver_data(device) = ac;
239
240	result = acpi_ac_get_state(ac);
241	if (result)
242		goto end;
243
244	result = acpi_ac_add_fs(device);
245	if (result)
246		goto end;
247
248	status = acpi_install_notify_handler(ac->handle,
249					     ACPI_DEVICE_NOTIFY, acpi_ac_notify,
250					     ac);
251	if (ACPI_FAILURE(status)) {
252		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
253				  "Error installing notify handler\n"));
254		result = -ENODEV;
255		goto end;
256	}
257
258	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
259	       acpi_device_name(device), acpi_device_bid(device),
260	       ac->state ? "on-line" : "off-line");
261
262      end:
263	if (result) {
264		acpi_ac_remove_fs(device);
265		kfree(ac);
266	}
267
268	return_VALUE(result);
269}
270
271static int acpi_ac_remove(struct acpi_device *device, int type)
272{
273	acpi_status status = AE_OK;
274	struct acpi_ac *ac = NULL;
275
276	ACPI_FUNCTION_TRACE("acpi_ac_remove");
277
278	if (!device || !acpi_driver_data(device))
279		return_VALUE(-EINVAL);
280
281	ac = (struct acpi_ac *)acpi_driver_data(device);
282
283	status = acpi_remove_notify_handler(ac->handle,
284					    ACPI_DEVICE_NOTIFY, acpi_ac_notify);
285	if (ACPI_FAILURE(status))
286		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
287				  "Error removing notify handler\n"));
288
289	acpi_ac_remove_fs(device);
290
291	kfree(ac);
292
293	return_VALUE(0);
294}
295
296static int __init acpi_ac_init(void)
297{
298	int result = 0;
299
300	ACPI_FUNCTION_TRACE("acpi_ac_init");
301
302	acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
303	if (!acpi_ac_dir)
304		return_VALUE(-ENODEV);
305	acpi_ac_dir->owner = THIS_MODULE;
306
307	result = acpi_bus_register_driver(&acpi_ac_driver);
308	if (result < 0) {
309		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
310		return_VALUE(-ENODEV);
311	}
312
313	return_VALUE(0);
314}
315
316static void __exit acpi_ac_exit(void)
317{
318	ACPI_FUNCTION_TRACE("acpi_ac_exit");
319
320	acpi_bus_unregister_driver(&acpi_ac_driver);
321
322	remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
323
324	return_VOID;
325}
326
327module_init(acpi_ac_init);
328module_exit(acpi_ac_exit);
329