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         void                    *data = 0;
  96         size_t                  size = 0;
  97
  98         ACPI_FUNCTION_TRACE("acpi_system_read_dsdt");
  99
 100         status = acpi_get_table(ACPI_TABLE_DSDT, 1, &dsdt);
 101         if (ACPI_FAILURE(status))
 102                 return_VALUE(-ENODEV);
 103
 104         if (*ppos < dsdt.length) {
 105                 data = dsdt.pointer + file->f_pos;
 106                 size = dsdt.length - file->f_pos;
 107                 if (size > count)
 108                         size = count;
 109                 if (copy_to_user(buffer, data, size)) {
 110                         acpi_os_free(dsdt.pointer);
 111                         return_VALUE(-EFAULT);
 112                 }
 113         }
 114
 115         acpi_os_free(dsdt.pointer);
 116
 117         *ppos += size;
 118
 119         return_VALUE(size);
 120 }
 121
 122
 123 static ssize_t acpi_system_read_fadt (struct file*, char __user *, size_t, loff_t*);
 124
 125 static struct file_operations acpi_system_fadt_ops = {
 126         .read =                 acpi_system_read_fadt,
 127 };
 128
 129 static ssize_t
 130 acpi_system_read_fadt (
 131         struct file             *file,
 132         char                    __user *buffer,
 133         size_t                  count,
 134         loff_t                  *ppos)
 135 {
 136         acpi_status             status = AE_OK;
 137         struct acpi_buffer      fadt = {ACPI_ALLOCATE_BUFFER, NULL};
 138         void                    *data = 0;
 139         size_t                  size = 0;
 140
 141         ACPI_FUNCTION_TRACE("acpi_system_read_fadt");
 142
 143         status = acpi_get_table(ACPI_TABLE_FADT, 1, &fadt);
 144         if (ACPI_FAILURE(status))
 145                 return_VALUE(-ENODEV);
 146
 147         if (*ppos < fadt.length) {
 148                 data = fadt.pointer + file->f_pos;
 149                 size = fadt.length - file->f_pos;
 150                 if (size > count)
 151                         size = count;
 152                 if (copy_to_user(buffer, data, size)) {
 153                         acpi_os_free(fadt.pointer);
 154                         return_VALUE(-EFAULT);
 155                 }
 156         }
 157
 158         acpi_os_free(fadt.pointer);
 159
 160         *ppos += size;
 161
 162         return_VALUE(size);
 163 }
 164
 165
 166 static int __init acpi_system_init (void)
 167 {
 168         struct proc_dir_entry   *entry;
 169         int error = 0;
 170         char * name;
 171
 172         ACPI_FUNCTION_TRACE("acpi_system_init");
 173
 174         if (acpi_disabled)
 175                 return_VALUE(0);
 176
 177         /* 'info' [R] */
 178         name = ACPI_SYSTEM_FILE_INFO;
 179         entry = create_proc_read_entry(name,
 180                 S_IRUGO, acpi_root_dir, acpi_system_read_info,NULL);
 181         if (!entry)
 182                 goto Error;
 183
 184         /* 'dsdt' [R] */
 185         name = ACPI_SYSTEM_FILE_DSDT;
 186         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 187         if (entry)
 188                 entry->proc_fops = &acpi_system_dsdt_ops;
 189         else
 190                 goto Error;
 191
 192         /* 'fadt' [R] */
 193         name = ACPI_SYSTEM_FILE_FADT;
 194         entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
 195         if (entry)
 196                 entry->proc_fops = &acpi_system_fadt_ops;
 197         else
 198                 goto Error;
 199
 200  Done:
 201         return_VALUE(error);
 202
 203  Error:
 204         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 205                          "Unable to create '%s' proc fs entry\n", name));
 206
 207         remove_proc_entry(ACPI_SYSTEM_FILE_FADT, acpi_root_dir);
 208         remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_root_dir);
 209         remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_root_dir);
 210
 211         error = -EFAULT;
 212         goto Done;
 213 }
 214
 215
 216 subsys_initcall(acpi_system_init);