drivers/input/misc/atlas_btns.c

   1 /*
   2  *  atlas_btns.c - Atlas Wallmount Touchscreen ACPI Extras
   3  *
   4  *  Copyright (C) 2006 Jaya Kumar
   5  *  Based on Toshiba ACPI by John Belmonte and ASUS ACPI
   6  *  This work was sponsored by CIS(M) Sdn Bhd.
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  */
  23
  24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/input.h>
  29 #include <linux/types.h>
  30 #include <linux/acpi.h>
  31 #include <linux/uaccess.h>
  32
  33 #define ACPI_ATLAS_NAME         "Atlas ACPI"
  34 #define ACPI_ATLAS_CLASS        "Atlas"
  35
  36 static unsigned short atlas_keymap[16];
  37 static struct input_dev *input_dev;
  38
  39 /* button handling code */
  40 static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
  41                     u32 function, void *handler_context, void **return_context)
  42 {
  43         *return_context =
  44                 (function != ACPI_REGION_DEACTIVATE) ? handler_context : NULL;
  45
  46         return AE_OK;
  47 }
  48
  49 static acpi_status acpi_atlas_button_handler(u32 function,
  50                       acpi_physical_address address,
  51                       u32 bit_width, u64 *value,
  52                       void *handler_context, void *region_context)
  53 {
  54         acpi_status status;
  55
  56         if (function == ACPI_WRITE) {
  57                 int code = address & 0x0f;
  58                 int key_down = !(address & 0x10);
  59
  60                 input_event(input_dev, EV_MSC, MSC_SCAN, code);
  61                 input_report_key(input_dev, atlas_keymap[code], key_down);
  62                 input_sync(input_dev);
  63
  64                 status = AE_OK;
  65         } else {
  66                 pr_warn("shrugged on unexpected function: function=%x,address=%lx,value=%x\n",
  67                         function, (unsigned long)address, (u32)*value);
  68                 status = AE_BAD_PARAMETER;
  69         }
  70
  71         return status;
  72 }
  73
  74 static int atlas_acpi_button_add(struct acpi_device *device)
  75 {
  76         acpi_status status;
  77         int i;
  78         int err;
  79
  80         input_dev = input_allocate_device();
  81         if (!input_dev) {
  82                 pr_err("unable to allocate input device\n");
  83                 return -ENOMEM;
  84         }
  85
  86         input_dev->name = "Atlas ACPI button driver";
  87         input_dev->phys = "ASIM0000/atlas/input0";
  88         input_dev->id.bustype = BUS_HOST;
  89         input_dev->keycode = atlas_keymap;
  90         input_dev->keycodesize = sizeof(unsigned short);
  91         input_dev->keycodemax = ARRAY_SIZE(atlas_keymap);
  92
  93         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
  94         __set_bit(EV_KEY, input_dev->evbit);
  95         for (i = 0; i < ARRAY_SIZE(atlas_keymap); i++) {
  96                 if (i < 9) {
  97                         atlas_keymap[i] = KEY_F1 + i;
  98                         __set_bit(KEY_F1 + i, input_dev->keybit);
  99                 } else
 100                         atlas_keymap[i] = KEY_RESERVED;
 101         }
 102
 103         err = input_register_device(input_dev);
 104         if (err) {
 105                 pr_err("couldn't register input device\n");
 106                 input_free_device(input_dev);
 107                 return err;
 108         }
 109
 110         /* hookup button handler */
 111         status = acpi_install_address_space_handler(device->handle,
 112                                 0x81, &acpi_atlas_button_handler,
 113                                 &acpi_atlas_button_setup, device);
 114         if (ACPI_FAILURE(status)) {
 115                 pr_err("error installing addr spc handler\n");
 116                 input_unregister_device(input_dev);
 117                 err = -EINVAL;
 118         }
 119
 120         return err;
 121 }
 122
 123 static int atlas_acpi_button_remove(struct acpi_device *device)
 124 {
 125         acpi_status status;
 126
 127         status = acpi_remove_address_space_handler(device->handle,
 128                                 0x81, &acpi_atlas_button_handler);
 129         if (ACPI_FAILURE(status))
 130                 pr_err("error removing addr spc handler\n");
 131
 132         input_unregister_device(input_dev);
 133
 134         return 0;
 135 }
 136
 137 static const struct acpi_device_id atlas_device_ids[] = {
 138         {"ASIM0000", 0},
 139         {"", 0},
 140 };
 141 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
 142
 143 static struct acpi_driver atlas_acpi_driver = {
 144         .name   = ACPI_ATLAS_NAME,
 145         .class  = ACPI_ATLAS_CLASS,
 146         .owner  = THIS_MODULE,
 147         .ids    = atlas_device_ids,
 148         .ops    = {
 149                 .add    = atlas_acpi_button_add,
 150                 .remove = atlas_acpi_button_remove,
 151         },
 152 };
 153 module_acpi_driver(atlas_acpi_driver);
 154
 155 MODULE_AUTHOR("Jaya Kumar");
 156 MODULE_LICENSE("GPL");
 157 MODULE_DESCRIPTION("Atlas button driver");
 158