xref: /openbmc/linux/drivers/acpi/ac.c (revision 64c70b1c)
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_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
46 ACPI_MODULE_NAME("ac");
47 
48 MODULE_AUTHOR("Paul Diefenbaugh");
49 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
50 MODULE_LICENSE("GPL");
51 
52 extern struct proc_dir_entry *acpi_lock_ac_dir(void);
53 extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
54 
55 static int acpi_ac_add(struct acpi_device *device);
56 static int acpi_ac_remove(struct acpi_device *device, int type);
57 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
58 
59 static 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 
69 struct acpi_ac {
70 	struct acpi_device * device;
71 	unsigned long state;
72 };
73 
74 static 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 
85 static 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 
107 static struct proc_dir_entry *acpi_ac_dir;
108 
109 static 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 
138 static 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 
143 static 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 
170 static 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 
187 static 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 
213 static 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 
261 static 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 
282 static 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 
302 static 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 
312 module_init(acpi_ac_init);
313 module_exit(acpi_ac_exit);
314