1/*
2 *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 1.1.1.1 $)
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_DEVICE_NAME		"AC Adapter"
39#define ACPI_AC_FILE_STATE		"state"
40#define ACPI_AC_NOTIFY_STATUS		0x80
41#define ACPI_AC_STATUS_OFFLINE		0x00
42#define ACPI_AC_STATUS_ONLINE		0x01
43#define ACPI_AC_STATUS_UNKNOWN		0xFF
44
45#define _COMPONENT		ACPI_AC_COMPONENT
46ACPI_MODULE_NAME("ac");
47
48MODULE_AUTHOR("Paul Diefenbaugh");
49MODULE_DESCRIPTION("ACPI AC Adapter Driver");
50MODULE_LICENSE("GPL");
51
52extern struct proc_dir_entry *acpi_lock_ac_dir(void);
53extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
54
55static int acpi_ac_add(struct acpi_device *device);
56static int acpi_ac_remove(struct acpi_device *device, int type);
57static int acpi_ac_open_fs(struct inode *inode, struct file *file);
58
59static struct acpi_driver acpi_ac_driver = {
60	.name = "ac",
61	.class = ACPI_AC_CLASS,
62	.ids = ACPI_AC_HID,
63	.ops = {
64		.add = acpi_ac_add,
65		.remove = acpi_ac_remove,
66		},
67};
68
69struct acpi_ac {
70	struct acpi_device * device;
71	unsigned long state;
72};
73
74static const struct file_operations acpi_ac_fops = {
75	.open = acpi_ac_open_fs,
76	.read = seq_read,
77	.llseek = seq_lseek,
78	.release = single_release,
79};
80
81/* --------------------------------------------------------------------------
82                               AC Adapter Management
83   -------------------------------------------------------------------------- */
84
85static int acpi_ac_get_state(struct acpi_ac *ac)
86{
87	acpi_status status = AE_OK;
88
89
90	if (!ac)
91		return -EINVAL;
92
93	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
94	if (ACPI_FAILURE(status)) {
95		ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
96		ac->state = ACPI_AC_STATUS_UNKNOWN;
97		return -ENODEV;
98	}
99
100	return 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 = seq->private;
112
113
114	if (!ac)
115		return 0;
116
117	if (acpi_ac_get_state(ac)) {
118		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
119		return 0;
120	}
121
122	seq_puts(seq, "state:                   ");
123	switch (ac->state) {
124	case ACPI_AC_STATUS_OFFLINE:
125		seq_puts(seq, "off-line\n");
126		break;
127	case ACPI_AC_STATUS_ONLINE:
128		seq_puts(seq, "on-line\n");
129		break;
130	default:
131		seq_puts(seq, "unknown\n");
132		break;
133	}
134
135	return 0;
136}
137
138static int acpi_ac_open_fs(struct inode *inode, struct file *file)
139{
140	return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
141}
142
143static int acpi_ac_add_fs(struct acpi_device *device)
144{
145	struct proc_dir_entry *entry = NULL;
146
147
148	if (!acpi_device_dir(device)) {
149		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
150						     acpi_ac_dir);
151		if (!acpi_device_dir(device))
152			return -ENODEV;
153		acpi_device_dir(device)->owner = THIS_MODULE;
154	}
155
156	/* 'state' [R] */
157	entry = create_proc_entry(ACPI_AC_FILE_STATE,
158				  S_IRUGO, acpi_device_dir(device));
159	if (!entry)
160		return -ENODEV;
161	else {
162		entry->proc_fops = &acpi_ac_fops;
163		entry->data = acpi_driver_data(device);
164		entry->owner = THIS_MODULE;
165	}
166
167	return 0;
168}
169
170static int acpi_ac_remove_fs(struct acpi_device *device)
171{
172
173	if (acpi_device_dir(device)) {
174		remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
175
176		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
177		acpi_device_dir(device) = NULL;
178	}
179
180	return 0;
181}
182
183/* --------------------------------------------------------------------------
184                                   Driver Model
185   -------------------------------------------------------------------------- */
186
187static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
188{
189	struct acpi_ac *ac = data;
190	struct acpi_device *device = NULL;
191
192
193	if (!ac)
194		return;
195
196	device = ac->device;
197	switch (event) {
198	case ACPI_AC_NOTIFY_STATUS:
199	case ACPI_NOTIFY_BUS_CHECK:
200	case ACPI_NOTIFY_DEVICE_CHECK:
201		acpi_ac_get_state(ac);
202		acpi_bus_generate_event(device, event, (u32) ac->state);
203		break;
204	default:
205		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
206				  "Unsupported event [0x%x]\n", event));
207		break;
208	}
209
210	return;
211}
212
213static int acpi_ac_add(struct acpi_device *device)
214{
215	int result = 0;
216	acpi_status status = AE_OK;
217	struct acpi_ac *ac = NULL;
218
219
220	if (!device)
221		return -EINVAL;
222
223	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
224	if (!ac)
225		return -ENOMEM;
226
227	ac->device = device;
228	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
229	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
230	acpi_driver_data(device) = ac;
231
232	result = acpi_ac_get_state(ac);
233	if (result)
234		goto end;
235
236	result = acpi_ac_add_fs(device);
237	if (result)
238		goto end;
239
240	status = acpi_install_notify_handler(device->handle,
241					     ACPI_ALL_NOTIFY, acpi_ac_notify,
242					     ac);
243	if (ACPI_FAILURE(status)) {
244		result = -ENODEV;
245		goto end;
246	}
247
248	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
249	       acpi_device_name(device), acpi_device_bid(device),
250	       ac->state ? "on-line" : "off-line");
251
252      end:
253	if (result) {
254		acpi_ac_remove_fs(device);
255		kfree(ac);
256	}
257
258	return result;
259}
260
261static int acpi_ac_remove(struct acpi_device *device, int type)
262{
263	acpi_status status = AE_OK;
264	struct acpi_ac *ac = NULL;
265
266
267	if (!device || !acpi_driver_data(device))
268		return -EINVAL;
269
270	ac = acpi_driver_data(device);
271
272	status = acpi_remove_notify_handler(device->handle,
273					    ACPI_ALL_NOTIFY, acpi_ac_notify);
274
275	acpi_ac_remove_fs(device);
276
277	kfree(ac);
278
279	return 0;
280}
281
282static int __init acpi_ac_init(void)
283{
284	int result;
285
286	if (acpi_disabled)
287		return -ENODEV;
288
289	acpi_ac_dir = acpi_lock_ac_dir();
290	if (!acpi_ac_dir)
291		return -ENODEV;
292
293	result = acpi_bus_register_driver(&acpi_ac_driver);
294	if (result < 0) {
295		acpi_unlock_ac_dir(acpi_ac_dir);
296		return -ENODEV;
297	}
298
299	return 0;
300}
301
302static void __exit acpi_ac_exit(void)
303{
304
305	acpi_bus_unregister_driver(&acpi_ac_driver);
306
307	acpi_unlock_ac_dir(acpi_ac_dir);
308
309	return;
310}
311
312module_init(acpi_ac_init);
313module_exit(acpi_ac_exit);
314