arch/sh/boards/hp6xx/hp6xx_apm.c

   1 /*
   2  * bios-less APM driver for hp680
   3  *
   4  * Copyright 2005 (c) Andriy Skulysh <askulysh@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License.
   8  */
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/apm-emulation.h>
  14 #include <linux/io.h>
  15 #include <asm/adc.h>
  16 #include <asm/hp6xx.h>
  17
  18 #define SH7709_PGDR                     0xa400012c
  19
  20 #define APM_CRITICAL                    10
  21 #define APM_LOW                         30
  22
  23 #define HP680_BATTERY_MAX               898
  24 #define HP680_BATTERY_MIN               486
  25 #define HP680_BATTERY_AC_ON             1023
  26
  27 #define MODNAME "hp6x0_apm"
  28
  29 static void hp6x0_apm_get_power_status(struct apm_power_info *info)
  30 {
  31         int battery, backup, charging, percentage;
  32         u8 pgdr;
  33
  34         battery         = adc_single(ADC_CHANNEL_BATTERY);
  35         backup          = adc_single(ADC_CHANNEL_BACKUP);
  36         charging        = adc_single(ADC_CHANNEL_CHARGE);
  37
  38         percentage = 100 * (battery - HP680_BATTERY_MIN) /
  39                            (HP680_BATTERY_MAX - HP680_BATTERY_MIN);
  40
  41         info->ac_line_status = (battery > HP680_BATTERY_AC_ON) ?
  42                          APM_AC_ONLINE : APM_AC_OFFLINE;
  43
  44         pgdr = ctrl_inb(SH7709_PGDR);
  45         if (pgdr & PGDR_MAIN_BATTERY_OUT) {
  46                 info->battery_status    = APM_BATTERY_STATUS_NOT_PRESENT;
  47                 info->battery_flag      = 0x80;
  48         } else if (charging < 8) {
  49                 info->battery_status    = APM_BATTERY_STATUS_CHARGING;
  50                 info->battery_flag      = 0x08;
  51                 info->ac_line_status = 0xff;
  52         } else if (percentage <= APM_CRITICAL) {
  53                 info->battery_status    = APM_BATTERY_STATUS_CRITICAL;
  54                 info->battery_flag      = 0x04;
  55         } else if (percentage <= APM_LOW) {
  56                 info->battery_status    = APM_BATTERY_STATUS_LOW;
  57                 info->battery_flag      = 0x02;
  58         } else {
  59                 info->battery_status    = APM_BATTERY_STATUS_HIGH;
  60                 info->battery_flag      = 0x01;
  61         }
  62
  63         info->units = 0;
  64 }
  65
  66 static irqreturn_t hp6x0_apm_interrupt(int irq, void *dev)
  67 {
  68         if (!APM_DISABLED)
  69                 apm_queue_event(APM_USER_SUSPEND);
  70
  71         return IRQ_HANDLED;
  72 }
  73
  74 static int __init hp6x0_apm_init(void)
  75 {
  76         int ret;
  77
  78         ret = request_irq(HP680_BTN_IRQ, hp6x0_apm_interrupt,
  79                           IRQF_DISABLED, MODNAME, NULL);
  80         if (unlikely(ret < 0)) {
  81                 printk(KERN_ERR MODNAME ": IRQ %d request failed\n",
  82                        HP680_BTN_IRQ);
  83                 return ret;
  84         }
  85
  86         apm_get_power_status = hp6x0_apm_get_power_status;
  87
  88         return ret;
  89 }
  90
  91 static void __exit hp6x0_apm_exit(void)
  92 {
  93         free_irq(HP680_BTN_IRQ, 0);
  94 }
  95
  96 module_init(hp6x0_apm_init);
  97 module_exit(hp6x0_apm_exit);
  98
  99 MODULE_AUTHOR("Adriy Skulysh");
 100 MODULE_DESCRIPTION("hp6xx Advanced Power Management");
 101 MODULE_LICENSE("GPL");