xref: /openbmc/linux/drivers/acpi/ac.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
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
47 ACPI_MODULE_NAME("acpi_ac")
48 
49     MODULE_AUTHOR("Paul Diefenbaugh");
50 MODULE_DESCRIPTION(ACPI_AC_DRIVER_NAME);
51 MODULE_LICENSE("GPL");
52 
53 static int acpi_ac_add(struct acpi_device *device);
54 static int acpi_ac_remove(struct acpi_device *device, int type);
55 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
56 
57 static 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 
67 struct acpi_ac {
68 	acpi_handle handle;
69 	unsigned long state;
70 };
71 
72 static 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 
83 static 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 
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 = (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 
139 static 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 
144 static 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 
174 static 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 
192 static 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 
219 static 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 
271 static 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 
296 static 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 
316 static 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 
327 module_init(acpi_ac_init);
328 module_exit(acpi_ac_exit);
329