parisc: sba_iommu: fix build bug when CONFIG_PARISC_AGP=y
[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         .owner = THIS_MODULE,
106         .open = acpi_system_open_event,
107         .read = acpi_system_read_event,
108         .release = acpi_system_close_event,
109         .poll = acpi_system_poll_event,
110 };
111 #endif  /* CONFIG_ACPI_PROC_EVENT */
112
113 /* ACPI notifier chain */
114 static BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
115
116 int acpi_notifier_call_chain(struct acpi_device *dev, u32 type, u32 data)
117 {
118         struct acpi_bus_event event;
119
120         strcpy(event.device_class, dev->pnp.device_class);
121         strcpy(event.bus_id, dev->pnp.bus_id);
122         event.type = type;
123         event.data = data;
124         return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event)
125                         == NOTIFY_BAD) ? -EINVAL : 0;
126 }
127 EXPORT_SYMBOL(acpi_notifier_call_chain);
128
129 int register_acpi_notifier(struct notifier_block *nb)
130 {
131         return blocking_notifier_chain_register(&acpi_chain_head, nb);
132 }
133 EXPORT_SYMBOL(register_acpi_notifier);
134
135 int unregister_acpi_notifier(struct notifier_block *nb)
136 {
137         return blocking_notifier_chain_unregister(&acpi_chain_head, nb);
138 }
139 EXPORT_SYMBOL(unregister_acpi_notifier);
140
141 #ifdef CONFIG_NET
142 static unsigned int acpi_event_seqnum;
143 struct acpi_genl_event {
144         acpi_device_class device_class;
145         char bus_id[15];
146         u32 type;
147         u32 data;
148 };
149
150 /* attributes of acpi_genl_family */
151 enum {
152         ACPI_GENL_ATTR_UNSPEC,
153         ACPI_GENL_ATTR_EVENT,   /* ACPI event info needed by user space */
154         __ACPI_GENL_ATTR_MAX,
155 };
156 #define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1)
157
158 /* commands supported by the acpi_genl_family */
159 enum {
160         ACPI_GENL_CMD_UNSPEC,
161         ACPI_GENL_CMD_EVENT,    /* kernel->user notifications for ACPI events */
162         __ACPI_GENL_CMD_MAX,
163 };
164 #define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1)
165
166 #define ACPI_GENL_FAMILY_NAME           "acpi_event"
167 #define ACPI_GENL_VERSION               0x01
168 #define ACPI_GENL_MCAST_GROUP_NAME      "acpi_mc_group"
169
170 static struct genl_family acpi_event_genl_family = {
171         .id = GENL_ID_GENERATE,
172         .name = ACPI_GENL_FAMILY_NAME,
173         .version = ACPI_GENL_VERSION,
174         .maxattr = ACPI_GENL_ATTR_MAX,
175 };
176
177 static struct genl_multicast_group acpi_event_mcgrp = {
178         .name = ACPI_GENL_MCAST_GROUP_NAME,
179 };
180
181 int acpi_bus_generate_netlink_event(const char *device_class,
182                                       const char *bus_id,
183                                       u8 type, int data)
184 {
185         struct sk_buff *skb;
186         struct nlattr *attr;
187         struct acpi_genl_event *event;
188         void *msg_header;
189         int size;
190         int result;
191
192         /* allocate memory */
193         size = nla_total_size(sizeof(struct acpi_genl_event)) +
194             nla_total_size(0);
195
196         skb = genlmsg_new(size, GFP_ATOMIC);
197         if (!skb)
198                 return -ENOMEM;
199
200         /* add the genetlink message header */
201         msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++,
202                                  &acpi_event_genl_family, 0,
203                                  ACPI_GENL_CMD_EVENT);
204         if (!msg_header) {
205                 nlmsg_free(skb);
206                 return -ENOMEM;
207         }
208
209         /* fill the data */
210         attr =
211             nla_reserve(skb, ACPI_GENL_ATTR_EVENT,
212                         sizeof(struct acpi_genl_event));
213         if (!attr) {
214                 nlmsg_free(skb);
215                 return -EINVAL;
216         }
217
218         event = nla_data(attr);
219         if (!event) {
220                 nlmsg_free(skb);
221                 return -EINVAL;
222         }
223
224         memset(event, 0, sizeof(struct acpi_genl_event));
225
226         strcpy(event->device_class, device_class);
227         strcpy(event->bus_id, bus_id);
228         event->type = type;
229         event->data = data;
230
231         /* send multicast genetlink message */
232         result = genlmsg_end(skb, msg_header);
233         if (result < 0) {
234                 nlmsg_free(skb);
235                 return result;
236         }
237
238         result =
239             genlmsg_multicast(skb, 0, acpi_event_mcgrp.id, GFP_ATOMIC);
240         if (result)
241                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
242                                   "Failed to send a Genetlink message!\n"));
243         return 0;
244 }
245
246 EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
247
248 static int acpi_event_genetlink_init(void)
249 {
250         int result;
251
252         result = genl_register_family(&acpi_event_genl_family);
253         if (result)
254                 return result;
255
256         result = genl_register_mc_group(&acpi_event_genl_family,
257                                         &acpi_event_mcgrp);
258         if (result)
259                 genl_unregister_family(&acpi_event_genl_family);
260
261         return result;
262 }
263
264 #else
265 int acpi_bus_generate_netlink_event(const char *device_class,
266                                       const char *bus_id,
267                                       u8 type, int data)
268 {
269         return 0;
270 }
271
272 EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
273
274 static int acpi_event_genetlink_init(void)
275 {
276         return -ENODEV;
277 }
278 #endif
279
280 static int __init acpi_event_init(void)
281 {
282 #ifdef CONFIG_ACPI_PROC_EVENT
283         struct proc_dir_entry *entry;
284 #endif
285         int error = 0;
286
287         if (acpi_disabled)
288                 return 0;
289
290         /* create genetlink for acpi event */
291         error = acpi_event_genetlink_init();
292         if (error)
293                 printk(KERN_WARNING PREFIX
294                        "Failed to create genetlink family for ACPI event\n");
295
296 #ifdef CONFIG_ACPI_PROC_EVENT
297         /* 'event' [R] */
298         entry = proc_create("event", S_IRUSR, acpi_root_dir,
299                             &acpi_system_event_ops);
300         if (!entry)
301                 return -ENODEV;
302 #endif
303
304         return 0;
305 }
306
307 fs_initcall(acpi_event_init);