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/init.h>
  28 #include <asm/uaccess.h>
  29
  30 #include <acpi/acpi_drivers.h>
  31
  32
  33 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
  34 ACPI_MODULE_NAME                ("acpi_system")
  35
  36 #define ACPI_SYSTEM_CLASS               "system"
  37 #define ACPI_SYSTEM_DRIVER_NAME         "ACPI System Driver"
  38 #define ACPI_SYSTEM_DEVICE_NAME         "System"
  39 #define ACPI_SYSTEM_FILE_INFO           "info"
  40 #define ACPI_SYSTEM_FILE_EVENT          "event"
  41 #define ACPI_SYSTEM_FILE_DSDT           "dsdt"
  42 #define ACPI_SYSTEM_FILE_FADT           "fadt"
  43
  44 extern FADT_DESCRIPTOR          acpi_fadt;
  45
  46 /* --------------------------------------------------------------------------
  47                               FS Interface (/proc)
  48    -------------------------------------------------------------------------- */
  49
  50 static int
  51 acpi_system_read_info (
  52         char                    *page,
  53         char                    **start,
  54         off_t                   off,
  55         int                     count,
  56         int                     *eof,
  57         void                    *data)
  58 {
  59         char                    *p = page;
  60         int                     size = 0;
  61
  62         ACPI_FUNCTION_TRACE("acpi_system_read_info");
  63
  64         if (off != 0)
  65                 goto end;
  66
  67         p += sprintf(p, "version:                 %x\n", ACPI_CA_VERSION);
  68
  69 end:
  70         size = (p - page);
  71         if (size <= off+count) *eof = 1;
  72         *start = page + off;
  73         size -= off;
  74         if (size>count) size = count;
  75         if (size<0) size = 0;
  76
  77         return_VALUE(size);
  78 }
  79
  80 static ssize_t acpi_system_read_dsdt (struct file*, char __user *, size_t, loff_t*);
  81
  82 static struct file_operations acpi_system_dsdt_ops = {
  83         .read =                 acpi_system_read_dsdt,
  84 };
  85
  86 static ssize_t
  87 acpi_system_read_dsdt (
  88         struct file             *file,
  89         char                    __user *buffer,
  90         size_t                  count,
  91         loff_t                  *ppos)
  92 {
  93         acpi_status             status = AE_OK;
  94         struct acpi_buffer      dsdt = {ACPI_ALLOCATE_BUFFER, NULL};
  95         ssize_t                 res;
  96
  97         ACPI_FUNCTION_TRACE("acpi_system_read_dsdt");
  98
  99         status = acpi_get_table(ACPI_TABLE_DSDT, 1, &dsdt);
 100         if (ACPI_FAILURE(status))
 101                 return_VALUE(-ENODEV);
 102
 103         res = simple_read_from_buffer(buffer, count, ppos,
 104                                       dsdt.pointer, dsdt.length);
 105         acpi_os_free(dsdt.pointer);
 106
 107         return_VALUE(res);
 108 }
 109
 110
 111 static ssize_t acpi_system_read_fadt (struct file*, char __user *, size_t, loff_t*);
 112
 113 static struct file_operations acpi_system_fadt_ops = {
 114         .read =                 acpi_system_read_fadt,
 115 };
 116
 117 static ssize_t
 118 acpi_system_read_fadt (
 119         struct file             *file,
 120         char                    __user *buffer,
 121         size_t                  count,
 122         loff_t                  *ppos)
 123 {
 124         acpi_status             status = AE_OK;
 125         struct acpi_buffer      fadt = {ACPI_ALLOCATE_BUFFER, NULL};
 126         ssize_t                 res;
 127
 128         ACPI_FUNCTION_TRACE("acpi_system_read_fadt");
 129
 130         status = acpi_get_table(ACPI_TABLE_FADT, 1, &fadt);
 131         if (ACPI_FAILURE(status))
 132                 return_VALUE(-ENODEV);
 133
 134         res = simple_read_from_buffer(buffer, count, ppos,
 135                                       fadt.pointer, fadt.length);
 136         acpi_os_free(fadt.pointer);
 137
 138         return_VALUE(res);
 139 }
 140
 141
 142 static int __init acpi_system_init (void)
 143 {
 144         struct proc_dir_entry   *entry;
 145         int error = 0;
 146         char * name;
 147
 148         ACPI_FUNCTION_TRACE("acpi_system_init");
 149
 150         if (acpi_disabled)
 151                 return_VALUE(0);
 152
 153         /* 'info' [R] */
 154         name = ACPI_SYSTEM_FILE_INFO;
 155         entry = create_proc_read_entry(name,
 156                 S_IRUGO, acpi_root_dir, acpi_system_read_info,NULL);
 157         if (!entry)
 158                 goto Error;
 159
 160         /* 'dsdt' [R] */
 161         name = ACPI_SYSTEM_FILE_DSDT;
 162         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 163         if (entry)
 164                 entry->proc_fops = &acpi_system_dsdt_ops;
 165         else
 166                 goto Error;
 167
 168         /* 'fadt' [R] */
 169         name = ACPI_SYSTEM_FILE_FADT;
 170         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 171         if (entry)
 172                 entry->proc_fops = &acpi_system_fadt_ops;
 173         else
 174                 goto Error;
 175
 176  Done:
 177         return_VALUE(error);
 178
 179  Error:
 180         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 181                          "Unable to create '%s' proc fs entry\n", name));
 182
 183         remove_proc_entry(ACPI_SYSTEM_FILE_FADT, acpi_root_dir);
 184         remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_root_dir);
 185         remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_root_dir);
 186
 187         error = -EFAULT;
 188         goto Done;
 189 }
 190
 191
 192 subsys_initcall(acpi_system_init);