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/config.h>
  32 #include <linux/input.h>
  33 #include <linux/slab.h>
  34 #include <linux/init.h>
  35 #include <linux/tty.h>
  36 #include <linux/delay.h>
  37 #include <linux/pm.h>
  38
  39 static struct input_handler power_handler;
  40
  41 /*
  42  * Power management can't be done in a interrupt context. So we have to
  43  * use keventd.
  44  */
  45 static int suspend_button_pushed = 0;
  46 static void suspend_button_task_handler(void *data)
  47 {
  48         udelay(200); /* debounce */
  49         suspend_button_pushed = 0;
  50 }
  51
  52 static DECLARE_WORK(suspend_button_task, suspend_button_task_handler, NULL);
  53
  54 static void power_event(struct input_handle *handle, unsigned int type,
  55                         unsigned int code, int down)
  56 {
  57         struct input_dev *dev = handle->dev;
  58
  59         printk("Entering power_event\n");
  60
  61         if (type == EV_PWR) {
  62                 switch (code) {
  63                         case KEY_SUSPEND:
  64                                 printk("Powering down entire device\n");
  65
  66                                 if (!suspend_button_pushed) {
  67                                         suspend_button_pushed = 1;
  68                                         schedule_work(&suspend_button_task);
  69                                 }
  70                                 break;
  71                         case KEY_POWER:
  72                                 /* Hum power down the machine. */
  73                                 break;
  74                         default:
  75                                 return;
  76                 }
  77         }
  78
  79         if (type == EV_KEY) {
  80                 switch (code) {
  81                         case KEY_SUSPEND:
  82                                 printk("Powering down input device\n");
  83                                 /* This is risky. See pm.h for details. */
  84                                 if (dev->state != PM_RESUME)
  85                                         dev->state = PM_RESUME;
  86                                 else
  87                                         dev->state = PM_SUSPEND;
  88                                 pm_send(dev->pm_dev, dev->state, dev);
  89                                 break;
  90                         case KEY_POWER:
  91                                 /* Turn the input device off completely ? */
  92                                 break;
  93                         default:
  94                                 return;
  95                 }
  96         }
  97         return;
  98 }
  99
 100 static struct input_handle *power_connect(struct input_handler *handler,
 101                                           struct input_dev *dev,
 102                                           struct input_device_id *id)
 103 {
 104         struct input_handle *handle;
 105
 106         if (!(handle = kmalloc(sizeof(struct input_handle), GFP_KERNEL)))
 107                 return NULL;
 108         memset(handle, 0, sizeof(struct input_handle));
 109
 110         handle->dev = dev;
 111         handle->handler = handler;
 112
 113         input_open_device(handle);
 114
 115         printk(KERN_INFO "power.c: Adding power management to input layer\n");
 116         return handle;
 117 }
 118
 119 static void power_disconnect(struct input_handle *handle)
 120 {
 121         input_close_device(handle);
 122         kfree(handle);
 123 }
 124
 125 static struct input_device_id power_ids[] = {
 126         {
 127                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
 128                 .evbit = { BIT(EV_KEY) },
 129                 .keybit = { [LONG(KEY_SUSPEND)] = BIT(KEY_SUSPEND) }
 130         },
 131         {
 132                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
 133                 .evbit = { BIT(EV_KEY) },
 134                 .keybit = { [LONG(KEY_POWER)] = BIT(KEY_POWER) }
 135         },
 136         {
 137                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
 138                 .evbit = { BIT(EV_PWR) },
 139         },
 140         { },    /* Terminating entry */
 141 };
 142
 143 MODULE_DEVICE_TABLE(input, power_ids);
 144
 145 static struct input_handler power_handler = {
 146         .event =        power_event,
 147         .connect =      power_connect,
 148         .disconnect =   power_disconnect,
 149         .name =         "power",
 150         .id_table =     power_ids,
 151 };
 152
 153 static int __init power_init(void)
 154 {
 155         input_register_handler(&power_handler);
 156         return 0;
 157 }
 158
 159 static void __exit power_exit(void)
 160 {
 161         input_unregister_handler(&power_handler);
 162 }
 163
 164 module_init(power_init);
 165 module_exit(power_exit);
 166
 167 MODULE_AUTHOR("James Simmons <jsimmons@transvirtual.com>");
 168 MODULE_DESCRIPTION("Input Power Management driver");
 169 MODULE_LICENSE("GPL");