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 <linux/acpi.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 const struct genl_multicast_group acpi_event_mcgrps[] = { 82 { .name = ACPI_GENL_MCAST_GROUP_NAME, }, 83 }; 84 85 static struct genl_family acpi_event_genl_family = { 86 .id = GENL_ID_GENERATE, 87 .name = ACPI_GENL_FAMILY_NAME, 88 .version = ACPI_GENL_VERSION, 89 .maxattr = ACPI_GENL_ATTR_MAX, 90 .mcgrps = acpi_event_mcgrps, 91 .n_mcgrps = ARRAY_SIZE(acpi_event_mcgrps), 92 }; 93 94 int acpi_bus_generate_netlink_event(const char *device_class, 95 const char *bus_id, 96 u8 type, int data) 97 { 98 struct sk_buff *skb; 99 struct nlattr *attr; 100 struct acpi_genl_event *event; 101 void *msg_header; 102 int size; 103 int result; 104 105 /* allocate memory */ 106 size = nla_total_size(sizeof(struct acpi_genl_event)) + 107 nla_total_size(0); 108 109 skb = genlmsg_new(size, GFP_ATOMIC); 110 if (!skb) 111 return -ENOMEM; 112 113 /* add the genetlink message header */ 114 msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++, 115 &acpi_event_genl_family, 0, 116 ACPI_GENL_CMD_EVENT); 117 if (!msg_header) { 118 nlmsg_free(skb); 119 return -ENOMEM; 120 } 121 122 /* fill the data */ 123 attr = 124 nla_reserve(skb, ACPI_GENL_ATTR_EVENT, 125 sizeof(struct acpi_genl_event)); 126 if (!attr) { 127 nlmsg_free(skb); 128 return -EINVAL; 129 } 130 131 event = nla_data(attr); 132 memset(event, 0, sizeof(struct acpi_genl_event)); 133 134 strcpy(event->device_class, device_class); 135 strcpy(event->bus_id, bus_id); 136 event->type = type; 137 event->data = data; 138 139 /* send multicast genetlink message */ 140 result = genlmsg_end(skb, msg_header); 141 if (result < 0) { 142 nlmsg_free(skb); 143 return result; 144 } 145 146 genlmsg_multicast(&acpi_event_genl_family, skb, 0, 0, GFP_ATOMIC); 147 return 0; 148 } 149 150 EXPORT_SYMBOL(acpi_bus_generate_netlink_event); 151 152 static int acpi_event_genetlink_init(void) 153 { 154 return genl_register_family(&acpi_event_genl_family); 155 } 156 157 #else 158 int acpi_bus_generate_netlink_event(const char *device_class, 159 const char *bus_id, 160 u8 type, int data) 161 { 162 return 0; 163 } 164 165 EXPORT_SYMBOL(acpi_bus_generate_netlink_event); 166 167 static int acpi_event_genetlink_init(void) 168 { 169 return -ENODEV; 170 } 171 #endif 172 173 static int __init acpi_event_init(void) 174 { 175 int error = 0; 176 177 if (acpi_disabled) 178 return 0; 179 180 /* create genetlink for acpi event */ 181 error = acpi_event_genetlink_init(); 182 if (error) 183 printk(KERN_WARNING PREFIX 184 "Failed to create genetlink family for ACPI event\n"); 185 return 0; 186 } 187 188 fs_initcall(acpi_event_init); 189