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