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/init.h>
  29 #include <linux/input.h>
  30 #include <linux/types.h>
  31 #include <asm/uaccess.h>
  32 #include <acpi/acpi_drivers.h>
  33
  34 #define ACPI_ATLAS_NAME         "Atlas ACPI"
  35 #define ACPI_ATLAS_CLASS        "Atlas"
  36
  37 static unsigned short atlas_keymap[16];
  38 static struct input_dev *input_dev;
  39
  40 /* button handling code */
  41 static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
  42                     u32 function, void *handler_context, void **return_context)
  43 {
  44         *return_context =
  45                 (function != ACPI_REGION_DEACTIVATE) ? handler_context : NULL;
  46
  47         return AE_OK;
  48 }
  49
  50 static acpi_status acpi_atlas_button_handler(u32 function,
  51                       acpi_physical_address address,
  52                       u32 bit_width, u64 *value,
  53                       void *handler_context, void *region_context)
  54 {
  55         acpi_status status;
  56
  57         if (function == ACPI_WRITE) {
  58                 int code = address & 0x0f;
  59                 int key_down = !(address & 0x10);
  60
  61                 input_event(input_dev, EV_MSC, MSC_SCAN, code);
  62                 input_report_key(input_dev, atlas_keymap[code], key_down);
  63                 input_sync(input_dev);
  64
  65                 status = AE_OK;
  66         } else {
  67                 pr_warn("shrugged on unexpected function: function=%x,address=%lx,value=%x\n",
  68                         function, (unsigned long)address, (u32)*value);
  69                 status = AE_BAD_PARAMETER;
  70         }
  71
  72         return status;
  73 }
  74
  75 static int atlas_acpi_button_add(struct acpi_device *device)
  76 {
  77         acpi_status status;
  78         int i;
  79         int err;
  80
  81         input_dev = input_allocate_device();
  82         if (!input_dev) {
  83                 pr_err("unable to allocate input device\n");
  84                 return -ENOMEM;
  85         }
  86
  87         input_dev->name = "Atlas ACPI button driver";
  88         input_dev->phys = "ASIM0000/atlas/input0";
  89         input_dev->id.bustype = BUS_HOST;
  90         input_dev->keycode = atlas_keymap;
  91         input_dev->keycodesize = sizeof(unsigned short);
  92         input_dev->keycodemax = ARRAY_SIZE(atlas_keymap);
  93
  94         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
  95         __set_bit(EV_KEY, input_dev->evbit);
  96         for (i = 0; i < ARRAY_SIZE(atlas_keymap); i++) {
  97                 if (i < 9) {
  98                         atlas_keymap[i] = KEY_F1 + i;
  99                         __set_bit(KEY_F1 + i, input_dev->keybit);
 100                 } else
 101                         atlas_keymap[i] = KEY_RESERVED;
 102         }
 103
 104         err = input_register_device(input_dev);
 105         if (err) {
 106                 pr_err("couldn't register input device\n");
 107                 input_free_device(input_dev);
 108                 return err;
 109         }
 110
 111         /* hookup button handler */
 112         status = acpi_install_address_space_handler(device->handle,
 113                                 0x81, &acpi_atlas_button_handler,
 114                                 &acpi_atlas_button_setup, device);
 115         if (ACPI_FAILURE(status)) {
 116                 pr_err("error installing addr spc handler\n");
 117                 input_unregister_device(input_dev);
 118                 err = -EINVAL;
 119         }
 120
 121         return err;
 122 }
 123
 124 static int atlas_acpi_button_remove(struct acpi_device *device, int type)
 125 {
 126         acpi_status status;
 127
 128         status = acpi_remove_address_space_handler(device->handle,
 129                                 0x81, &acpi_atlas_button_handler);
 130         if (ACPI_FAILURE(status))
 131                 pr_err("error removing addr spc handler\n");
 132
 133         input_unregister_device(input_dev);
 134
 135         return 0;
 136 }
 137
 138 static const struct acpi_device_id atlas_device_ids[] = {
 139         {"ASIM0000", 0},
 140         {"", 0},
 141 };
 142 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
 143
 144 static struct acpi_driver atlas_acpi_driver = {
 145         .name   = ACPI_ATLAS_NAME,
 146         .class  = ACPI_ATLAS_CLASS,
 147         .owner  = THIS_MODULE,
 148         .ids    = atlas_device_ids,
 149         .ops    = {
 150                 .add    = atlas_acpi_button_add,
 151                 .remove = atlas_acpi_button_remove,
 152         },
 153 };
 154
 155 static int __init atlas_acpi_init(void)
 156 {
 157         if (acpi_disabled)
 158                 return -ENODEV;
 159
 160         return acpi_bus_register_driver(&atlas_acpi_driver);
 161 }
 162
 163 static void __exit atlas_acpi_exit(void)
 164 {
 165         acpi_bus_unregister_driver(&atlas_acpi_driver);
 166 }
 167
 168 module_init(atlas_acpi_init);
 169 module_exit(atlas_acpi_exit);
 170
 171 MODULE_AUTHOR("Jaya Kumar");
 172 MODULE_LICENSE("GPL");
 173 MODULE_DESCRIPTION("Atlas button driver");
 174