drivers/input/power.c

   1 /*
   2  * $Id: power.c,v 1.10 2001/09/25 09:17:15 vojtech Exp $
   3  *
   4  *  Copyright (c) 2001 "Crazy" James Simmons
   5  *
   6  *  Input driver Power Management.
   7  *
   8  *  Sponsored by Transvirtual Technology.
   9  */
  10
  11 /*
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  *
  26  * Should you need to contact me, the author, you can do so by
  27  * e-mail - mail your message to <jsimmons@transvirtual.com>.
  28  */
  29
  30 #include <linux/module.h>
  31 #include <linux/input.h>
  32 #include <linux/slab.h>
  33 #include <linux/init.h>
  34 #include <linux/tty.h>
  35 #include <linux/delay.h>
  36 #include <linux/pm.h>
  37
  38 static struct input_handler power_handler;
  39
  40 /*
  41  * Power management can't be done in a interrupt context. So we have to
  42  * use keventd.
  43  */
  44 static int suspend_button_pushed = 0;
  45 static void suspend_button_task_handler(void *data)
  46 {
  47         udelay(200); /* debounce */
  48         suspend_button_pushed = 0;
  49 }
  50
  51 static DECLARE_WORK(suspend_button_task, suspend_button_task_handler, NULL);
  52
  53 static void power_event(struct input_handle *handle, unsigned int type,
  54                         unsigned int code, int down)
  55 {
  56         struct input_dev *dev = handle->dev;
  57
  58         printk("Entering power_event\n");
  59
  60         if (type == EV_PWR) {
  61                 switch (code) {
  62                         case KEY_SUSPEND:
  63                                 printk("Powering down entire device\n");
  64
  65                                 if (!suspend_button_pushed) {
  66                                         suspend_button_pushed = 1;
  67                                         schedule_work(&suspend_button_task);
  68                                 }
  69                                 break;
  70                         case KEY_POWER:
  71                                 /* Hum power down the machine. */
  72                                 break;
  73                         default:
  74                                 return;
  75                 }
  76         }
  77
  78         if (type == EV_KEY) {
  79                 switch (code) {
  80                         case KEY_SUSPEND:
  81                                 printk("Powering down input device\n");
  82                                 /* This is risky. See pm.h for details. */
  83                                 if (dev->state != PM_RESUME)
  84                                         dev->state = PM_RESUME;
  85                                 else
  86                                         dev->state = PM_SUSPEND;
  87                                 pm_send(dev->pm_dev, dev->state, dev);
  88                                 break;
  89                         case KEY_POWER:
  90                                 /* Turn the input device off completely ? */
  91                                 break;
  92                         default:
  93                                 return;
  94                 }
  95         }
  96         return;
  97 }
  98
  99 static struct input_handle *power_connect(struct input_handler *handler,
 100                                           struct input_dev *dev,
 101                                           const struct input_device_id *id)
 102 {
 103         struct input_handle *handle;
 104
 105         if (!(handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL)))
 106                 return NULL;
 107
 108         handle->dev = dev;
 109         handle->handler = handler;
 110
 111         input_open_device(handle);
 112
 113         printk(KERN_INFO "power.c: Adding power management to input layer\n");
 114         return handle;
 115 }
 116
 117 static void power_disconnect(struct input_handle *handle)
 118 {
 119         input_close_device(handle);
 120         kfree(handle);
 121 }
 122
 123 static const struct input_device_id power_ids[] = {
 124         {
 125                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
 126                 .evbit = { BIT(EV_KEY) },
 127                 .keybit = { [LONG(KEY_SUSPEND)] = BIT(KEY_SUSPEND) }
 128         },
 129         {
 130                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
 131                 .evbit = { BIT(EV_KEY) },
 132                 .keybit = { [LONG(KEY_POWER)] = BIT(KEY_POWER) }
 133         },
 134         {
 135                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
 136                 .evbit = { BIT(EV_PWR) },
 137         },
 138         { },    /* Terminating entry */
 139 };
 140
 141 MODULE_DEVICE_TABLE(input, power_ids);
 142
 143 static struct input_handler power_handler = {
 144         .event =        power_event,
 145         .connect =      power_connect,
 146         .disconnect =   power_disconnect,
 147         .name =         "power",
 148         .id_table =     power_ids,
 149 };
 150
 151 static int __init power_init(void)
 152 {
 153         return input_register_handler(&power_handler);
 154 }
 155
 156 static void __exit power_exit(void)
 157 {
 158         input_unregister_handler(&power_handler);
 159 }
 160
 161 module_init(power_init);
 162 module_exit(power_exit);
 163
 164 MODULE_AUTHOR("James Simmons <jsimmons@transvirtual.com>");
 165 MODULE_DESCRIPTION("Input Power Management driver");
 166 MODULE_LICENSE("GPL");