xref: /openbmc/linux/drivers/acpi/ac.c (revision c21b37f6)
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_DEVICE_NAME		"AC Adapter"
38 #define ACPI_AC_FILE_STATE		"state"
39 #define ACPI_AC_NOTIFY_STATUS		0x80
40 #define ACPI_AC_STATUS_OFFLINE		0x00
41 #define ACPI_AC_STATUS_ONLINE		0x01
42 #define ACPI_AC_STATUS_UNKNOWN		0xFF
43 
44 #define _COMPONENT		ACPI_AC_COMPONENT
45 ACPI_MODULE_NAME("ac");
46 
47 MODULE_AUTHOR("Paul Diefenbaugh");
48 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
49 MODULE_LICENSE("GPL");
50 
51 extern struct proc_dir_entry *acpi_lock_ac_dir(void);
52 extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
53 
54 static int acpi_ac_add(struct acpi_device *device);
55 static int acpi_ac_remove(struct acpi_device *device, int type);
56 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
57 
58 const static struct acpi_device_id ac_device_ids[] = {
59 	{"ACPI0003", 0},
60 	{"", 0},
61 };
62 MODULE_DEVICE_TABLE(acpi, ac_device_ids);
63 
64 static struct acpi_driver acpi_ac_driver = {
65 	.name = "ac",
66 	.class = ACPI_AC_CLASS,
67 	.ids = ac_device_ids,
68 	.ops = {
69 		.add = acpi_ac_add,
70 		.remove = acpi_ac_remove,
71 		},
72 };
73 
74 struct acpi_ac {
75 	struct acpi_device * device;
76 	unsigned long state;
77 };
78 
79 static const struct file_operations acpi_ac_fops = {
80 	.open = acpi_ac_open_fs,
81 	.read = seq_read,
82 	.llseek = seq_lseek,
83 	.release = single_release,
84 };
85 
86 /* --------------------------------------------------------------------------
87                                AC Adapter Management
88    -------------------------------------------------------------------------- */
89 
90 static int acpi_ac_get_state(struct acpi_ac *ac)
91 {
92 	acpi_status status = AE_OK;
93 
94 
95 	if (!ac)
96 		return -EINVAL;
97 
98 	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
99 	if (ACPI_FAILURE(status)) {
100 		ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
101 		ac->state = ACPI_AC_STATUS_UNKNOWN;
102 		return -ENODEV;
103 	}
104 
105 	return 0;
106 }
107 
108 /* --------------------------------------------------------------------------
109                               FS Interface (/proc)
110    -------------------------------------------------------------------------- */
111 
112 static struct proc_dir_entry *acpi_ac_dir;
113 
114 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
115 {
116 	struct acpi_ac *ac = seq->private;
117 
118 
119 	if (!ac)
120 		return 0;
121 
122 	if (acpi_ac_get_state(ac)) {
123 		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
124 		return 0;
125 	}
126 
127 	seq_puts(seq, "state:                   ");
128 	switch (ac->state) {
129 	case ACPI_AC_STATUS_OFFLINE:
130 		seq_puts(seq, "off-line\n");
131 		break;
132 	case ACPI_AC_STATUS_ONLINE:
133 		seq_puts(seq, "on-line\n");
134 		break;
135 	default:
136 		seq_puts(seq, "unknown\n");
137 		break;
138 	}
139 
140 	return 0;
141 }
142 
143 static int acpi_ac_open_fs(struct inode *inode, struct file *file)
144 {
145 	return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
146 }
147 
148 static int acpi_ac_add_fs(struct acpi_device *device)
149 {
150 	struct proc_dir_entry *entry = NULL;
151 
152 
153 	if (!acpi_device_dir(device)) {
154 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
155 						     acpi_ac_dir);
156 		if (!acpi_device_dir(device))
157 			return -ENODEV;
158 		acpi_device_dir(device)->owner = THIS_MODULE;
159 	}
160 
161 	/* 'state' [R] */
162 	entry = create_proc_entry(ACPI_AC_FILE_STATE,
163 				  S_IRUGO, acpi_device_dir(device));
164 	if (!entry)
165 		return -ENODEV;
166 	else {
167 		entry->proc_fops = &acpi_ac_fops;
168 		entry->data = acpi_driver_data(device);
169 		entry->owner = THIS_MODULE;
170 	}
171 
172 	return 0;
173 }
174 
175 static int acpi_ac_remove_fs(struct acpi_device *device)
176 {
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 0;
186 }
187 
188 /* --------------------------------------------------------------------------
189                                    Driver Model
190    -------------------------------------------------------------------------- */
191 
192 static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
193 {
194 	struct acpi_ac *ac = data;
195 	struct acpi_device *device = NULL;
196 
197 
198 	if (!ac)
199 		return;
200 
201 	device = ac->device;
202 	switch (event) {
203 	case ACPI_AC_NOTIFY_STATUS:
204 	case ACPI_NOTIFY_BUS_CHECK:
205 	case ACPI_NOTIFY_DEVICE_CHECK:
206 		acpi_ac_get_state(ac);
207 		acpi_bus_generate_event(device, event, (u32) ac->state);
208 		break;
209 	default:
210 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
211 				  "Unsupported event [0x%x]\n", event));
212 		break;
213 	}
214 
215 	return;
216 }
217 
218 static int acpi_ac_add(struct acpi_device *device)
219 {
220 	int result = 0;
221 	acpi_status status = AE_OK;
222 	struct acpi_ac *ac = NULL;
223 
224 
225 	if (!device)
226 		return -EINVAL;
227 
228 	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
229 	if (!ac)
230 		return -ENOMEM;
231 
232 	ac->device = device;
233 	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
234 	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
235 	acpi_driver_data(device) = ac;
236 
237 	result = acpi_ac_get_state(ac);
238 	if (result)
239 		goto end;
240 
241 	result = acpi_ac_add_fs(device);
242 	if (result)
243 		goto end;
244 
245 	status = acpi_install_notify_handler(device->handle,
246 					     ACPI_ALL_NOTIFY, acpi_ac_notify,
247 					     ac);
248 	if (ACPI_FAILURE(status)) {
249 		result = -ENODEV;
250 		goto end;
251 	}
252 
253 	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
254 	       acpi_device_name(device), acpi_device_bid(device),
255 	       ac->state ? "on-line" : "off-line");
256 
257       end:
258 	if (result) {
259 		acpi_ac_remove_fs(device);
260 		kfree(ac);
261 	}
262 
263 	return result;
264 }
265 
266 static int acpi_ac_remove(struct acpi_device *device, int type)
267 {
268 	acpi_status status = AE_OK;
269 	struct acpi_ac *ac = NULL;
270 
271 
272 	if (!device || !acpi_driver_data(device))
273 		return -EINVAL;
274 
275 	ac = acpi_driver_data(device);
276 
277 	status = acpi_remove_notify_handler(device->handle,
278 					    ACPI_ALL_NOTIFY, acpi_ac_notify);
279 
280 	acpi_ac_remove_fs(device);
281 
282 	kfree(ac);
283 
284 	return 0;
285 }
286 
287 static int __init acpi_ac_init(void)
288 {
289 	int result;
290 
291 	if (acpi_disabled)
292 		return -ENODEV;
293 
294 	acpi_ac_dir = acpi_lock_ac_dir();
295 	if (!acpi_ac_dir)
296 		return -ENODEV;
297 
298 	result = acpi_bus_register_driver(&acpi_ac_driver);
299 	if (result < 0) {
300 		acpi_unlock_ac_dir(acpi_ac_dir);
301 		return -ENODEV;
302 	}
303 
304 	return 0;
305 }
306 
307 static void __exit acpi_ac_exit(void)
308 {
309 
310 	acpi_bus_unregister_driver(&acpi_ac_driver);
311 
312 	acpi_unlock_ac_dir(acpi_ac_dir);
313 
314 	return;
315 }
316 
317 module_init(acpi_ac_init);
318 module_exit(acpi_ac_exit);
319