1 /*
2  *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 26 $)
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/compatmac.h>
31 #include <linux/proc_fs.h>
32 #include <acpi/acpi_bus.h>
33 #include <acpi/acpi_drivers.h>
34 
35 
36 #define _COMPONENT		ACPI_AC_COMPONENT
37 ACPI_MODULE_NAME		("acpi_ac")
38 
39 MODULE_AUTHOR("Paul Diefenbaugh");
40 MODULE_DESCRIPTION(ACPI_AC_DRIVER_NAME);
41 MODULE_LICENSE("GPL");
42 
43 #define PREFIX			"ACPI: "
44 
45 
46 int acpi_ac_add (struct acpi_device *device);
47 int acpi_ac_remove (struct acpi_device *device, int type);
48 
49 static struct acpi_driver acpi_ac_driver = {
50 	.name =		ACPI_AC_DRIVER_NAME,
51 	.class =	ACPI_AC_CLASS,
52 	.ids =		ACPI_AC_HID,
53 	.ops =		{
54 				.add =		acpi_ac_add,
55 				.remove =	acpi_ac_remove,
56 			},
57 };
58 
59 struct acpi_ac {
60 	acpi_handle		handle;
61 	unsigned long		state;
62 };
63 
64 
65 /* --------------------------------------------------------------------------
66                                AC Adapter Management
67    -------------------------------------------------------------------------- */
68 
69 static int
acpi_ac_get_state(struct acpi_ac * ac)70 acpi_ac_get_state (
71 	struct acpi_ac		*ac)
72 {
73 	acpi_status		status = AE_OK;
74 
75 	ACPI_FUNCTION_TRACE("acpi_ac_get_state");
76 
77 	if (!ac)
78 		return_VALUE(-EINVAL);
79 
80 	status = acpi_evaluate_integer(ac->handle, "_PSR", NULL, &ac->state);
81 	if (ACPI_FAILURE(status)) {
82 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
83 			"Error reading AC Adapter state\n"));
84 		ac->state = ACPI_AC_STATUS_UNKNOWN;
85 		return_VALUE(-ENODEV);
86 	}
87 
88 	return_VALUE(0);
89 }
90 
91 
92 /* --------------------------------------------------------------------------
93                               FS Interface (/proc)
94    -------------------------------------------------------------------------- */
95 
96 struct proc_dir_entry		*acpi_ac_dir;
97 
98 static int
acpi_ac_read_state(char * page,char ** start,off_t off,int count,int * eof,void * data)99 acpi_ac_read_state (
100 	char			*page,
101 	char			**start,
102 	off_t			off,
103 	int 			count,
104 	int 			*eof,
105 	void			*data)
106 {
107 	struct acpi_ac		*ac = (struct acpi_ac *) data;
108 	char			*p = page;
109 	int			len = 0;
110 
111 	ACPI_FUNCTION_TRACE("acpi_ac_read_state");
112 
113 	if (!ac || (off != 0))
114 		goto end;
115 
116 	if (acpi_ac_get_state(ac)) {
117 		p += sprintf(p, "ERROR: Unable to read AC Adapter state\n");
118 		goto end;
119 	}
120 
121 	p += sprintf(p, "state:                   ");
122 	switch (ac->state) {
123 	case ACPI_AC_STATUS_OFFLINE:
124 		p += sprintf(p, "off-line\n");
125 		break;
126 	case ACPI_AC_STATUS_ONLINE:
127 		p += sprintf(p, "on-line\n");
128 		break;
129 	default:
130 		p += sprintf(p, "unknown\n");
131 		break;
132 	}
133 
134 end:
135 	len = (p - page);
136 	if (len <= off+count) *eof = 1;
137 	*start = page + off;
138 	len -= off;
139 	if (len>count) len = count;
140 	if (len<0) len = 0;
141 
142 	return_VALUE(len);
143 }
144 
145 
146 static int
acpi_ac_add_fs(struct acpi_device * device)147 acpi_ac_add_fs (
148 	struct acpi_device	*device)
149 {
150 	struct proc_dir_entry	*entry = NULL;
151 
152 	ACPI_FUNCTION_TRACE("acpi_ac_add_fs");
153 
154 	if (!acpi_device_dir(device)) {
155 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
156 			acpi_ac_dir);
157 		if (!acpi_device_dir(device))
158 			return_VALUE(-ENODEV);
159 		acpi_device_dir(device)->owner = THIS_MODULE;
160 	}
161 
162 	/* 'state' [R] */
163 	entry = create_proc_entry(ACPI_AC_FILE_STATE,
164 		S_IRUGO, acpi_device_dir(device));
165 	if (!entry)
166 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
167 			"Unable to create '%s' fs entry\n",
168 			ACPI_AC_FILE_STATE));
169 	else {
170 		entry->read_proc = acpi_ac_read_state;
171 		entry->data = acpi_driver_data(device);
172 		entry->owner = THIS_MODULE;
173 	}
174 
175 	return_VALUE(0);
176 }
177 
178 
179 static int
acpi_ac_remove_fs(struct acpi_device * device)180 acpi_ac_remove_fs (
181 	struct acpi_device	*device)
182 {
183 	ACPI_FUNCTION_TRACE("acpi_ac_remove_fs");
184 
185 	if (acpi_device_dir(device)) {
186 		remove_proc_entry(ACPI_AC_FILE_STATE,
187 				  acpi_device_dir(device));
188 		remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
189 		acpi_device_dir(device) = NULL;
190 	}
191 
192 	return_VALUE(0);
193 }
194 
195 
196 /* --------------------------------------------------------------------------
197                                    Driver Model
198    -------------------------------------------------------------------------- */
199 
200 void
acpi_ac_notify(acpi_handle handle,u32 event,void * data)201 acpi_ac_notify (
202 	acpi_handle		handle,
203 	u32			event,
204 	void			*data)
205 {
206 	struct acpi_ac		*ac = (struct acpi_ac *) data;
207 	struct acpi_device	*device = NULL;
208 
209 	ACPI_FUNCTION_TRACE("acpi_ac_notify");
210 
211 	if (!ac)
212 		return;
213 
214 	if (acpi_bus_get_device(ac->handle, &device))
215 		return_VOID;
216 
217 	switch (event) {
218 	case ACPI_AC_NOTIFY_STATUS:
219 		acpi_ac_get_state(ac);
220 		acpi_bus_generate_event(device, event, (u32) ac->state);
221 		break;
222 	default:
223 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
224 			"Unsupported event [0x%x]\n", event));
225 		break;
226 	}
227 
228 	return_VOID;
229 }
230 
231 
232 int
acpi_ac_add(struct acpi_device * device)233 acpi_ac_add (
234 	struct acpi_device	*device)
235 {
236 	int			result = 0;
237 	acpi_status		status = AE_OK;
238 	struct acpi_ac		*ac = NULL;
239 
240 	ACPI_FUNCTION_TRACE("acpi_ac_add");
241 
242 	if (!device)
243 		return_VALUE(-EINVAL);
244 
245 	ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
246 	if (!ac)
247 		return_VALUE(-ENOMEM);
248 	memset(ac, 0, sizeof(struct acpi_ac));
249 
250 	ac->handle = device->handle;
251 	sprintf(acpi_device_name(device), "%s", ACPI_AC_DEVICE_NAME);
252 	sprintf(acpi_device_class(device), "%s", ACPI_AC_CLASS);
253 	acpi_driver_data(device) = ac;
254 
255 	result = acpi_ac_get_state(ac);
256 	if (result)
257 		goto end;
258 
259 	result = acpi_ac_add_fs(device);
260 	if (result)
261 		goto end;
262 
263 	status = acpi_install_notify_handler(ac->handle,
264 		ACPI_DEVICE_NOTIFY, acpi_ac_notify, ac);
265 	if (ACPI_FAILURE(status)) {
266 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
267 			"Error installing notify handler\n"));
268 		result = -ENODEV;
269 		goto end;
270 	}
271 
272 	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
273 		acpi_device_name(device), acpi_device_bid(device),
274 		ac->state?"on-line":"off-line");
275 
276 end:
277 	if (result) {
278 		acpi_ac_remove_fs(device);
279 		kfree(ac);
280 	}
281 
282 	return_VALUE(result);
283 }
284 
285 
286 int
acpi_ac_remove(struct acpi_device * device,int type)287 acpi_ac_remove (
288 	struct acpi_device	*device,
289 	int			type)
290 {
291 	acpi_status		status = AE_OK;
292 	struct acpi_ac		*ac = NULL;
293 
294 	ACPI_FUNCTION_TRACE("acpi_ac_remove");
295 
296 	if (!device || !acpi_driver_data(device))
297 		return_VALUE(-EINVAL);
298 
299 	ac = (struct acpi_ac *) acpi_driver_data(device);
300 
301 	status = acpi_remove_notify_handler(ac->handle,
302 		ACPI_DEVICE_NOTIFY, acpi_ac_notify);
303 	if (ACPI_FAILURE(status))
304 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
305 			"Error removing notify handler\n"));
306 
307 	acpi_ac_remove_fs(device);
308 
309 	kfree(ac);
310 
311 	return_VALUE(0);
312 }
313 
314 
315 int __init
acpi_ac_init(void)316 acpi_ac_init (void)
317 {
318 	int			result = 0;
319 
320 	ACPI_FUNCTION_TRACE("acpi_ac_init");
321 
322 	acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
323 	if (!acpi_ac_dir)
324 		return_VALUE(-ENODEV);
325 	acpi_ac_dir->owner = THIS_MODULE;
326 
327 	result = acpi_bus_register_driver(&acpi_ac_driver);
328 	if (result < 0) {
329 		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
330 		return_VALUE(-ENODEV);
331 	}
332 
333 	return_VALUE(0);
334 }
335 
336 
337 void __exit
acpi_ac_exit(void)338 acpi_ac_exit (void)
339 {
340 	ACPI_FUNCTION_TRACE("acpi_ac_exit");
341 
342 	acpi_bus_unregister_driver(&acpi_ac_driver);
343 
344 	remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
345 
346 	return_VOID;
347 }
348 
349 
350 module_init(acpi_ac_init);
351 module_exit(acpi_ac_exit);
352