drivers/acpi/system.c

   1 /*
   2  *  acpi_system.c - ACPI System Driver ($Revision: 63 $)
   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/proc_fs.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/init.h>
  29 #include <asm/uaccess.h>
  30
  31 #include <acpi/acpi_drivers.h>
  32
  33 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
  34 ACPI_MODULE_NAME("acpi_system")
  35 #ifdef MODULE_PARAM_PREFIX
  36 #undef MODULE_PARAM_PREFIX
  37 #endif
  38 #define MODULE_PARAM_PREFIX "acpi."
  39
  40 #define ACPI_SYSTEM_CLASS               "system"
  41 #define ACPI_SYSTEM_DRIVER_NAME         "ACPI System Driver"
  42 #define ACPI_SYSTEM_DEVICE_NAME         "System"
  43 #define ACPI_SYSTEM_FILE_INFO           "info"
  44 #define ACPI_SYSTEM_FILE_EVENT          "event"
  45 #define ACPI_SYSTEM_FILE_DSDT           "dsdt"
  46 #define ACPI_SYSTEM_FILE_FADT           "fadt"
  47
  48 /*
  49  * Make ACPICA version work as module param
  50  */
  51 static int param_get_acpica_version(char *buffer, struct kernel_param *kp) {
  52         int result;
  53
  54         result = sprintf(buffer, "%x", ACPI_CA_VERSION);
  55
  56         return result;
  57 }
  58
  59 module_param_call(acpica_version, NULL, param_get_acpica_version, NULL, 0444);
  60
  61 /* --------------------------------------------------------------------------
  62                               FS Interface (/proc)
  63    -------------------------------------------------------------------------- */
  64 #ifdef CONFIG_ACPI_PROCFS
  65
  66 static int acpi_system_read_info(struct seq_file *seq, void *offset)
  67 {
  68
  69         seq_printf(seq, "version:                 %x\n", ACPI_CA_VERSION);
  70         return 0;
  71 }
  72
  73 static int acpi_system_info_open_fs(struct inode *inode, struct file *file)
  74 {
  75         return single_open(file, acpi_system_read_info, PDE(inode)->data);
  76 }
  77
  78 static const struct file_operations acpi_system_info_ops = {
  79         .open = acpi_system_info_open_fs,
  80         .read = seq_read,
  81         .llseek = seq_lseek,
  82         .release = single_release,
  83 };
  84 #endif
  85
  86 static ssize_t acpi_system_read_dsdt(struct file *, char __user *, size_t,
  87                                      loff_t *);
  88
  89 static const struct file_operations acpi_system_dsdt_ops = {
  90         .read = acpi_system_read_dsdt,
  91 };
  92
  93 static ssize_t
  94 acpi_system_read_dsdt(struct file *file,
  95                       char __user * buffer, size_t count, loff_t * ppos)
  96 {
  97         acpi_status status = AE_OK;
  98         struct acpi_table_header *dsdt = NULL;
  99         ssize_t res;
 100
 101
 102         status = acpi_get_table(ACPI_SIG_DSDT, 1, &dsdt);
 103         if (ACPI_FAILURE(status))
 104                 return -ENODEV;
 105
 106         res = simple_read_from_buffer(buffer, count, ppos,
 107                                       dsdt, dsdt->length);
 108
 109         return res;
 110 }
 111
 112 static ssize_t acpi_system_read_fadt(struct file *, char __user *, size_t,
 113                                      loff_t *);
 114
 115 static const struct file_operations acpi_system_fadt_ops = {
 116         .read = acpi_system_read_fadt,
 117 };
 118
 119 static ssize_t
 120 acpi_system_read_fadt(struct file *file,
 121                       char __user * buffer, size_t count, loff_t * ppos)
 122 {
 123         acpi_status status = AE_OK;
 124         struct acpi_table_header *fadt = NULL;
 125         ssize_t res;
 126
 127
 128         status = acpi_get_table(ACPI_SIG_FADT, 1, &fadt);
 129         if (ACPI_FAILURE(status))
 130                 return -ENODEV;
 131
 132         res = simple_read_from_buffer(buffer, count, ppos,
 133                                       fadt, fadt->length);
 134
 135         return res;
 136 }
 137
 138 static int __init acpi_system_init(void)
 139 {
 140         struct proc_dir_entry *entry;
 141         int error = 0;
 142         char *name;
 143
 144
 145         if (acpi_disabled)
 146                 return 0;
 147
 148 #ifdef CONFIG_ACPI_PROCFS
 149         /* 'info' [R] */
 150         name = ACPI_SYSTEM_FILE_INFO;
 151         entry = create_proc_entry(name, S_IRUGO, acpi_root_dir);
 152         if (!entry)
 153                 goto Error;
 154         else {
 155                 entry->proc_fops = &acpi_system_info_ops;
 156         }
 157 #endif
 158
 159         /* 'dsdt' [R] */
 160         name = ACPI_SYSTEM_FILE_DSDT;
 161         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 162         if (entry)
 163                 entry->proc_fops = &acpi_system_dsdt_ops;
 164         else
 165                 goto Error;
 166
 167         /* 'fadt' [R] */
 168         name = ACPI_SYSTEM_FILE_FADT;
 169         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 170         if (entry)
 171                 entry->proc_fops = &acpi_system_fadt_ops;
 172         else
 173                 goto Error;
 174
 175       Done:
 176         return error;
 177
 178       Error:
 179         remove_proc_entry(ACPI_SYSTEM_FILE_FADT, acpi_root_dir);
 180         remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_root_dir);
 181 #ifdef CONFIG_ACPI_PROCFS
 182         remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_root_dir);
 183 #endif
 184
 185         error = -EFAULT;
 186         goto Done;
 187 }
 188
 189 subsys_initcall(acpi_system_init);