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/export.h> 11 #include <linux/proc_fs.h> 12 #include <linux/init.h> 13 #include <linux/poll.h> 14 #include <linux/gfp.h> 15 #include <acpi/acpi_drivers.h> 16 #include <net/netlink.h> 17 #include <net/genetlink.h> 18 19 #include "internal.h" 20 21 #define _COMPONENT ACPI_SYSTEM_COMPONENT 22 ACPI_MODULE_NAME("event"); 23 24 /* ACPI notifier chain */ 25 static BLOCKING_NOTIFIER_HEAD(acpi_chain_head); 26 27 int acpi_notifier_call_chain(struct acpi_device *dev, u32 type, u32 data) 28 { 29 struct acpi_bus_event event; 30 31 strcpy(event.device_class, dev->pnp.device_class); 32 strcpy(event.bus_id, dev->pnp.bus_id); 33 event.type = type; 34 event.data = data; 35 return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event) 36 == NOTIFY_BAD) ? -EINVAL : 0; 37 } 38 EXPORT_SYMBOL(acpi_notifier_call_chain); 39 40 int register_acpi_notifier(struct notifier_block *nb) 41 { 42 return blocking_notifier_chain_register(&acpi_chain_head, nb); 43 } 44 EXPORT_SYMBOL(register_acpi_notifier); 45 46 int unregister_acpi_notifier(struct notifier_block *nb) 47 { 48 return blocking_notifier_chain_unregister(&acpi_chain_head, nb); 49 } 50 EXPORT_SYMBOL(unregister_acpi_notifier); 51 52 #ifdef CONFIG_NET 53 static unsigned int acpi_event_seqnum; 54 struct acpi_genl_event { 55 acpi_device_class device_class; 56 char bus_id[15]; 57 u32 type; 58 u32 data; 59 }; 60 61 /* attributes of acpi_genl_family */ 62 enum { 63 ACPI_GENL_ATTR_UNSPEC, 64 ACPI_GENL_ATTR_EVENT, /* ACPI event info needed by user space */ 65 __ACPI_GENL_ATTR_MAX, 66 }; 67 #define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1) 68 69 /* commands supported by the acpi_genl_family */ 70 enum { 71 ACPI_GENL_CMD_UNSPEC, 72 ACPI_GENL_CMD_EVENT, /* kernel->user notifications for ACPI events */ 73 __ACPI_GENL_CMD_MAX, 74 }; 75 #define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1) 76 77 #define ACPI_GENL_FAMILY_NAME "acpi_event" 78 #define ACPI_GENL_VERSION 0x01 79 #define ACPI_GENL_MCAST_GROUP_NAME "acpi_mc_group" 80 81 static struct genl_family acpi_event_genl_family = { 82 .id = GENL_ID_GENERATE, 83 .name = ACPI_GENL_FAMILY_NAME, 84 .version = ACPI_GENL_VERSION, 85 .maxattr = ACPI_GENL_ATTR_MAX, 86 }; 87 88 static struct genl_multicast_group acpi_event_mcgrp = { 89 .name = ACPI_GENL_MCAST_GROUP_NAME, 90 }; 91 92 int acpi_bus_generate_netlink_event(const char *device_class, 93 const char *bus_id, 94 u8 type, int data) 95 { 96 struct sk_buff *skb; 97 struct nlattr *attr; 98 struct acpi_genl_event *event; 99 void *msg_header; 100 int size; 101 int result; 102 103 /* allocate memory */ 104 size = nla_total_size(sizeof(struct acpi_genl_event)) + 105 nla_total_size(0); 106 107 skb = genlmsg_new(size, GFP_ATOMIC); 108 if (!skb) 109 return -ENOMEM; 110 111 /* add the genetlink message header */ 112 msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++, 113 &acpi_event_genl_family, 0, 114 ACPI_GENL_CMD_EVENT); 115 if (!msg_header) { 116 nlmsg_free(skb); 117 return -ENOMEM; 118 } 119 120 /* fill the data */ 121 attr = 122 nla_reserve(skb, ACPI_GENL_ATTR_EVENT, 123 sizeof(struct acpi_genl_event)); 124 if (!attr) { 125 nlmsg_free(skb); 126 return -EINVAL; 127 } 128 129 event = nla_data(attr); 130 if (!event) { 131 nlmsg_free(skb); 132 return -EINVAL; 133 } 134 135 memset(event, 0, sizeof(struct acpi_genl_event)); 136 137 strcpy(event->device_class, device_class); 138 strcpy(event->bus_id, bus_id); 139 event->type = type; 140 event->data = data; 141 142 /* send multicast genetlink message */ 143 result = genlmsg_end(skb, msg_header); 144 if (result < 0) { 145 nlmsg_free(skb); 146 return result; 147 } 148 149 genlmsg_multicast(skb, 0, acpi_event_mcgrp.id, GFP_ATOMIC); 150 return 0; 151 } 152 153 EXPORT_SYMBOL(acpi_bus_generate_netlink_event); 154 155 static int acpi_event_genetlink_init(void) 156 { 157 int result; 158 159 result = genl_register_family(&acpi_event_genl_family); 160 if (result) 161 return result; 162 163 result = genl_register_mc_group(&acpi_event_genl_family, 164 &acpi_event_mcgrp); 165 if (result) 166 genl_unregister_family(&acpi_event_genl_family); 167 168 return result; 169 } 170 171 #else 172 int acpi_bus_generate_netlink_event(const char *device_class, 173 const char *bus_id, 174 u8 type, int data) 175 { 176 return 0; 177 } 178 179 EXPORT_SYMBOL(acpi_bus_generate_netlink_event); 180 181 static int acpi_event_genetlink_init(void) 182 { 183 return -ENODEV; 184 } 185 #endif 186 187 static int __init acpi_event_init(void) 188 { 189 int error = 0; 190 191 if (acpi_disabled) 192 return 0; 193 194 /* create genetlink for acpi event */ 195 error = acpi_event_genetlink_init(); 196 if (error) 197 printk(KERN_WARNING PREFIX 198 "Failed to create genetlink family for ACPI event\n"); 199 return 0; 200 } 201 202 fs_initcall(acpi_event_init); 203