xref: /openbmc/linux/drivers/acpi/ac.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 
36 #define ACPI_AC_COMPONENT		0x00020000
37 #define ACPI_AC_CLASS			"ac_adapter"
38 #define ACPI_AC_HID 			"ACPI0003"
39 #define ACPI_AC_DRIVER_NAME		"ACPI AC Adapter Driver"
40 #define ACPI_AC_DEVICE_NAME		"AC Adapter"
41 #define ACPI_AC_FILE_STATE		"state"
42 #define ACPI_AC_NOTIFY_STATUS		0x80
43 #define ACPI_AC_STATUS_OFFLINE		0x00
44 #define ACPI_AC_STATUS_ONLINE		0x01
45 #define ACPI_AC_STATUS_UNKNOWN		0xFF
46 
47 #define _COMPONENT		ACPI_AC_COMPONENT
48 ACPI_MODULE_NAME		("acpi_ac")
49 
50 MODULE_AUTHOR("Paul Diefenbaugh");
51 MODULE_DESCRIPTION(ACPI_AC_DRIVER_NAME);
52 MODULE_LICENSE("GPL");
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 static struct acpi_driver acpi_ac_driver = {
59 	.name =		ACPI_AC_DRIVER_NAME,
60 	.class =	ACPI_AC_CLASS,
61 	.ids =		ACPI_AC_HID,
62 	.ops =		{
63 				.add =		acpi_ac_add,
64 				.remove =	acpi_ac_remove,
65 			},
66 };
67 
68 struct acpi_ac {
69 	acpi_handle		handle;
70 	unsigned long		state;
71 };
72 
73 static struct file_operations acpi_ac_fops = {
74 	.open		= acpi_ac_open_fs,
75 	.read		= seq_read,
76 	.llseek		= seq_lseek,
77 	.release	= single_release,
78 };
79 
80 /* --------------------------------------------------------------------------
81                                AC Adapter Management
82    -------------------------------------------------------------------------- */
83 
84 static int
85 acpi_ac_get_state (
86 	struct acpi_ac		*ac)
87 {
88 	acpi_status		status = AE_OK;
89 
90 	ACPI_FUNCTION_TRACE("acpi_ac_get_state");
91 
92 	if (!ac)
93 		return_VALUE(-EINVAL);
94 
95 	status = acpi_evaluate_integer(ac->handle, "_PSR", NULL, &ac->state);
96 	if (ACPI_FAILURE(status)) {
97 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
98 			"Error reading AC Adapter state\n"));
99 		ac->state = ACPI_AC_STATUS_UNKNOWN;
100 		return_VALUE(-ENODEV);
101 	}
102 
103 	return_VALUE(0);
104 }
105 
106 
107 /* --------------------------------------------------------------------------
108                               FS Interface (/proc)
109    -------------------------------------------------------------------------- */
110 
111 static struct proc_dir_entry	*acpi_ac_dir;
112 
113 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
114 {
115 	struct acpi_ac		*ac = (struct acpi_ac *) seq->private;
116 
117 	ACPI_FUNCTION_TRACE("acpi_ac_seq_show");
118 
119 	if (!ac)
120 		return_VALUE(0);
121 
122 	if (acpi_ac_get_state(ac)) {
123 		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
124 		return_VALUE(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_VALUE(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
149 acpi_ac_add_fs (
150 	struct acpi_device	*device)
151 {
152 	struct proc_dir_entry	*entry = NULL;
153 
154 	ACPI_FUNCTION_TRACE("acpi_ac_add_fs");
155 
156 	if (!acpi_device_dir(device)) {
157 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
158 			acpi_ac_dir);
159 		if (!acpi_device_dir(device))
160 			return_VALUE(-ENODEV);
161 		acpi_device_dir(device)->owner = THIS_MODULE;
162 	}
163 
164 	/* 'state' [R] */
165 	entry = create_proc_entry(ACPI_AC_FILE_STATE,
166 		S_IRUGO, acpi_device_dir(device));
167 	if (!entry)
168 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
169 			"Unable to create '%s' fs entry\n",
170 			ACPI_AC_FILE_STATE));
171 	else {
172 		entry->proc_fops = &acpi_ac_fops;
173 		entry->data = acpi_driver_data(device);
174 		entry->owner = THIS_MODULE;
175 	}
176 
177 	return_VALUE(0);
178 }
179 
180 
181 static int
182 acpi_ac_remove_fs (
183 	struct acpi_device	*device)
184 {
185 	ACPI_FUNCTION_TRACE("acpi_ac_remove_fs");
186 
187 	if (acpi_device_dir(device)) {
188 		remove_proc_entry(ACPI_AC_FILE_STATE,
189 				  acpi_device_dir(device));
190 
191 		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
192 		acpi_device_dir(device) = NULL;
193 	}
194 
195 	return_VALUE(0);
196 }
197 
198 
199 /* --------------------------------------------------------------------------
200                                    Driver Model
201    -------------------------------------------------------------------------- */
202 
203 static void
204 acpi_ac_notify (
205 	acpi_handle		handle,
206 	u32			event,
207 	void			*data)
208 {
209 	struct acpi_ac		*ac = (struct acpi_ac *) data;
210 	struct acpi_device	*device = NULL;
211 
212 	ACPI_FUNCTION_TRACE("acpi_ac_notify");
213 
214 	if (!ac)
215 		return_VOID;
216 
217 	if (acpi_bus_get_device(ac->handle, &device))
218 		return_VOID;
219 
220 	switch (event) {
221 	case ACPI_AC_NOTIFY_STATUS:
222 		acpi_ac_get_state(ac);
223 		acpi_bus_generate_event(device, event, (u32) ac->state);
224 		break;
225 	default:
226 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
227 			"Unsupported event [0x%x]\n", event));
228 		break;
229 	}
230 
231 	return_VOID;
232 }
233 
234 
235 static int
236 acpi_ac_add (
237 	struct acpi_device	*device)
238 {
239 	int			result = 0;
240 	acpi_status		status = AE_OK;
241 	struct acpi_ac		*ac = NULL;
242 
243 	ACPI_FUNCTION_TRACE("acpi_ac_add");
244 
245 	if (!device)
246 		return_VALUE(-EINVAL);
247 
248 	ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
249 	if (!ac)
250 		return_VALUE(-ENOMEM);
251 	memset(ac, 0, sizeof(struct acpi_ac));
252 
253 	ac->handle = device->handle;
254 	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
255 	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
256 	acpi_driver_data(device) = ac;
257 
258 	result = acpi_ac_get_state(ac);
259 	if (result)
260 		goto end;
261 
262 	result = acpi_ac_add_fs(device);
263 	if (result)
264 		goto end;
265 
266 	status = acpi_install_notify_handler(ac->handle,
267 		ACPI_DEVICE_NOTIFY, acpi_ac_notify, ac);
268 	if (ACPI_FAILURE(status)) {
269 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
270 			"Error installing notify handler\n"));
271 		result = -ENODEV;
272 		goto end;
273 	}
274 
275 	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
276 		acpi_device_name(device), acpi_device_bid(device),
277 		ac->state?"on-line":"off-line");
278 
279 end:
280 	if (result) {
281 		acpi_ac_remove_fs(device);
282 		kfree(ac);
283 	}
284 
285 	return_VALUE(result);
286 }
287 
288 
289 static int
290 acpi_ac_remove (
291 	struct acpi_device	*device,
292 	int			type)
293 {
294 	acpi_status		status = AE_OK;
295 	struct acpi_ac		*ac = NULL;
296 
297 	ACPI_FUNCTION_TRACE("acpi_ac_remove");
298 
299 	if (!device || !acpi_driver_data(device))
300 		return_VALUE(-EINVAL);
301 
302 	ac = (struct acpi_ac *) acpi_driver_data(device);
303 
304 	status = acpi_remove_notify_handler(ac->handle,
305 		ACPI_DEVICE_NOTIFY, acpi_ac_notify);
306 	if (ACPI_FAILURE(status))
307 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
308 			"Error removing notify handler\n"));
309 
310 	acpi_ac_remove_fs(device);
311 
312 	kfree(ac);
313 
314 	return_VALUE(0);
315 }
316 
317 
318 static int __init
319 acpi_ac_init (void)
320 {
321 	int			result = 0;
322 
323 	ACPI_FUNCTION_TRACE("acpi_ac_init");
324 
325 	acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
326 	if (!acpi_ac_dir)
327 		return_VALUE(-ENODEV);
328 	acpi_ac_dir->owner = THIS_MODULE;
329 
330 	result = acpi_bus_register_driver(&acpi_ac_driver);
331 	if (result < 0) {
332 		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
333 		return_VALUE(-ENODEV);
334 	}
335 
336 	return_VALUE(0);
337 }
338 
339 
340 static void __exit
341 acpi_ac_exit (void)
342 {
343 	ACPI_FUNCTION_TRACE("acpi_ac_exit");
344 
345 	acpi_bus_unregister_driver(&acpi_ac_driver);
346 
347 	remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
348 
349 	return_VOID;
350 }
351 
352 
353 module_init(acpi_ac_init);
354 module_exit(acpi_ac_exit);
355