ACPI: fix ia64 allnoconfig build
[linux-2.6.git] / drivers / acpi / event.c
1 /*
2  * event.c - exporting ACPI events via procfs
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 #include <linux/spinlock.h>
10 #include <linux/proc_fs.h>
11 #include <linux/init.h>
12 #include <linux/poll.h>
13 #include <acpi/acpi_drivers.h>
14 #include <net/netlink.h>
15 #include <net/genetlink.h>
16
17 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
18 ACPI_MODULE_NAME("event");
19
20 #ifdef CONFIG_ACPI_PROC_EVENT
21 /* Global vars for handling event proc entry */
22 static DEFINE_SPINLOCK(acpi_system_event_lock);
23 int event_is_open = 0;
24 extern struct list_head acpi_bus_event_list;
25 extern wait_queue_head_t acpi_bus_event_queue;
26
27 static int acpi_system_open_event(struct inode *inode, struct file *file)
28 {
29         spin_lock_irq(&acpi_system_event_lock);
30
31         if (event_is_open)
32                 goto out_busy;
33
34         event_is_open = 1;
35
36         spin_unlock_irq(&acpi_system_event_lock);
37         return 0;
38
39       out_busy:
40         spin_unlock_irq(&acpi_system_event_lock);
41         return -EBUSY;
42 }
43
44 static ssize_t
45 acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
46                        loff_t * ppos)
47 {
48         int result = 0;
49         struct acpi_bus_event event;
50         static char str[ACPI_MAX_STRING];
51         static int chars_remaining = 0;
52         static char *ptr;
53
54         if (!chars_remaining) {
55                 memset(&event, 0, sizeof(struct acpi_bus_event));
56
57                 if ((file->f_flags & O_NONBLOCK)
58                     && (list_empty(&acpi_bus_event_list)))
59                         return -EAGAIN;
60
61                 result = acpi_bus_receive_event(&event);
62                 if (result)
63                         return result;
64
65                 chars_remaining = sprintf(str, "%s %s %08x %08x\n",
66                                           event.device_class ? event.
67                                           device_class : "<unknown>",
68                                           event.bus_id ? event.
69                                           bus_id : "<unknown>", event.type,
70                                           event.data);
71                 ptr = str;
72         }
73
74         if (chars_remaining < count) {
75                 count = chars_remaining;
76         }
77
78         if (copy_to_user(buffer, ptr, count))
79                 return -EFAULT;
80
81         *ppos += count;
82         chars_remaining -= count;
83         ptr += count;
84
85         return count;
86 }
87
88 static int acpi_system_close_event(struct inode *inode, struct file *file)
89 {
90         spin_lock_irq(&acpi_system_event_lock);
91         event_is_open = 0;
92         spin_unlock_irq(&acpi_system_event_lock);
93         return 0;
94 }
95
96 static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait)
97 {
98         poll_wait(file, &acpi_bus_event_queue, wait);
99         if (!list_empty(&acpi_bus_event_list))
100                 return POLLIN | POLLRDNORM;
101         return 0;
102 }
103
104 static const struct file_operations acpi_system_event_ops = {
105         .open = acpi_system_open_event,
106         .read = acpi_system_read_event,
107         .release = acpi_system_close_event,
108         .poll = acpi_system_poll_event,
109 };
110 #endif  /* CONFIG_ACPI_PROC_EVENT */
111
112 #ifdef CONFIG_NET
113 static unsigned int acpi_event_seqnum;
114 struct acpi_genl_event {
115         acpi_device_class device_class;
116         char bus_id[15];
117         u32 type;
118         u32 data;
119 };
120
121 /* attributes of acpi_genl_family */
122 enum {
123         ACPI_GENL_ATTR_UNSPEC,
124         ACPI_GENL_ATTR_EVENT,   /* ACPI event info needed by user space */
125         __ACPI_GENL_ATTR_MAX,
126 };
127 #define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1)
128
129 /* commands supported by the acpi_genl_family */
130 enum {
131         ACPI_GENL_CMD_UNSPEC,
132         ACPI_GENL_CMD_EVENT,    /* kernel->user notifications for ACPI events */
133         __ACPI_GENL_CMD_MAX,
134 };
135 #define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1)
136
137 #define ACPI_GENL_FAMILY_NAME           "acpi_event"
138 #define ACPI_GENL_VERSION               0x01
139 #define ACPI_GENL_MCAST_GROUP_NAME      "acpi_mc_group"
140
141 static struct genl_family acpi_event_genl_family = {
142         .id = GENL_ID_GENERATE,
143         .name = ACPI_GENL_FAMILY_NAME,
144         .version = ACPI_GENL_VERSION,
145         .maxattr = ACPI_GENL_ATTR_MAX,
146 };
147
148 static struct genl_multicast_group acpi_event_mcgrp = {
149         .name = ACPI_GENL_MCAST_GROUP_NAME,
150 };
151
152 int acpi_bus_generate_netlink_event(const char *device_class,
153                                       const char *bus_id,
154                                       u8 type, int data)
155 {
156         struct sk_buff *skb;
157         struct nlattr *attr;
158         struct acpi_genl_event *event;
159         void *msg_header;
160         int size;
161         int result;
162
163         /* allocate memory */
164         size = nla_total_size(sizeof(struct acpi_genl_event)) +
165             nla_total_size(0);
166
167         skb = genlmsg_new(size, GFP_ATOMIC);
168         if (!skb)
169                 return -ENOMEM;
170
171         /* add the genetlink message header */
172         msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++,
173                                  &acpi_event_genl_family, 0,
174                                  ACPI_GENL_CMD_EVENT);
175         if (!msg_header) {
176                 nlmsg_free(skb);
177                 return -ENOMEM;
178         }
179
180         /* fill the data */
181         attr =
182             nla_reserve(skb, ACPI_GENL_ATTR_EVENT,
183                         sizeof(struct acpi_genl_event));
184         if (!attr) {
185                 nlmsg_free(skb);
186                 return -EINVAL;
187         }
188
189         event = nla_data(attr);
190         if (!event) {
191                 nlmsg_free(skb);
192                 return -EINVAL;
193         }
194
195         memset(event, 0, sizeof(struct acpi_genl_event));
196
197         strcpy(event->device_class, device_class);
198         strcpy(event->bus_id, bus_id);
199         event->type = type;
200         event->data = data;
201
202         /* send multicast genetlink message */
203         result = genlmsg_end(skb, msg_header);
204         if (result < 0) {
205                 nlmsg_free(skb);
206                 return result;
207         }
208
209         result =
210             genlmsg_multicast(skb, 0, acpi_event_mcgrp.id, GFP_ATOMIC);
211         if (result)
212                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
213                                   "Failed to send a Genetlink message!\n"));
214         return 0;
215 }
216
217 EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
218
219 static int acpi_event_genetlink_init(void)
220 {
221         int result;
222
223         result = genl_register_family(&acpi_event_genl_family);
224         if (result)
225                 return result;
226
227         result = genl_register_mc_group(&acpi_event_genl_family,
228                                         &acpi_event_mcgrp);
229         if (result)
230                 genl_unregister_family(&acpi_event_genl_family);
231
232         return result;
233 }
234
235 #else
236 int acpi_bus_generate_netlink_event(const char *device_class,
237                                       const char *bus_id,
238                                       u8 type, int data)
239 {
240         return 0;
241 }
242
243 EXPORT_SYMBOL(acpi_generate_netlink_event);
244
245 static int acpi_event_genetlink_init(void)
246 {
247         return -ENODEV;
248 }
249 #endif
250
251 static int __init acpi_event_init(void)
252 {
253 #ifdef CONFIG_ACPI_PROC_EVENT
254         struct proc_dir_entry *entry;
255 #endif
256         int error = 0;
257
258         if (acpi_disabled)
259                 return 0;
260
261         /* create genetlink for acpi event */
262         error = acpi_event_genetlink_init();
263         if (error)
264                 printk(KERN_WARNING PREFIX
265                        "Failed to create genetlink family for ACPI event\n");
266
267 #ifdef CONFIG_ACPI_PROC_EVENT
268         /* 'event' [R] */
269         entry = create_proc_entry("event", S_IRUSR, acpi_root_dir);
270         if (entry)
271                 entry->proc_fops = &acpi_system_event_ops;
272         else
273                 return -ENODEV;
274 #endif
275
276         return 0;
277 }
278
279 fs_initcall(acpi_event_init);