LXR linux/arch/sh/boards/mach-hp6xx/hp6xx

   1/*
   2 * bios-less APM driver for hp680
   3 *
   4 * Copyright 2005 (c) Andriy Skulysh <askulysh@gmail.com>
   5 * Copyright 2008 (c) Kristoffer Ericson <kristoffer.ericson@gmail.com>
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License.
   9 */
  10#include <linux/module.h>
  11#include <linux/kernel.h>
  12#include <linux/init.h>
  13#include <linux/interrupt.h>
  14#include <linux/apm-emulation.h>
  15#include <linux/io.h>
  16#include <asm/adc.h>
  17#include <mach/hp6xx.h>
  18
  19/* percentage values */
  20#define APM_CRITICAL                    10
  21#define APM_LOW                         30
  22
  23/* resonably sane values */
  24#define HP680_BATTERY_MAX               898
  25#define HP680_BATTERY_MIN               486
  26#define HP680_BATTERY_AC_ON             1023
  27
  28#define MODNAME "hp6x0_apm"
  29
  30#define PGDR    0xa400012c
  31
  32static void hp6x0_apm_get_power_status(struct apm_power_info *info)
  33{
  34        int battery, backup, charging, percentage;
  35        u8 pgdr;
  36
  37        battery         = adc_single(ADC_CHANNEL_BATTERY);
  38        backup          = adc_single(ADC_CHANNEL_BACKUP);
  39        charging        = adc_single(ADC_CHANNEL_CHARGE);
  40
  41        percentage = 100 * (battery - HP680_BATTERY_MIN) /
  42                           (HP680_BATTERY_MAX - HP680_BATTERY_MIN);
  43
  44        /* % of full battery */
  45        info->battery_life = percentage;
  46
  47        /* We want our estimates in minutes */
  48        info->units = 0;
  49
  50        /* Extremely(!!) rough estimate, we will replace this with a datalist later on */
  51        info->time = (2 * battery);
  52
  53        info->ac_line_status = (battery > HP680_BATTERY_AC_ON) ?
  54                         APM_AC_ONLINE : APM_AC_OFFLINE;
  55
  56        pgdr = __raw_readb(PGDR);
  57        if (pgdr & PGDR_MAIN_BATTERY_OUT) {
  58                info->battery_status    = APM_BATTERY_STATUS_NOT_PRESENT;
  59                info->battery_flag      = 0x80;
  60        } else if (charging < 8) {
  61                info->battery_status    = APM_BATTERY_STATUS_CHARGING;
  62                info->battery_flag      = 0x08;
  63                info->ac_line_status    = 0x01;
  64        } else if (percentage <= APM_CRITICAL) {
  65                info->battery_status    = APM_BATTERY_STATUS_CRITICAL;
  66                info->battery_flag      = 0x04;
  67        } else if (percentage <= APM_LOW) {
  68                info->battery_status    = APM_BATTERY_STATUS_LOW;
  69                info->battery_flag      = 0x02;
  70        } else {
  71                info->battery_status    = APM_BATTERY_STATUS_HIGH;
  72                info->battery_flag      = 0x01;
  73        }
  74}
  75
  76static irqreturn_t hp6x0_apm_interrupt(int irq, void *dev)
  77{
  78        if (!APM_DISABLED)
  79                apm_queue_event(APM_USER_SUSPEND);
  80
  81        return IRQ_HANDLED;
  82}
  83
  84static int __init hp6x0_apm_init(void)
  85{
  86        int ret;
  87
  88        ret = request_irq(HP680_BTN_IRQ, hp6x0_apm_interrupt,
  89                          0, MODNAME, NULL);
  90        if (unlikely(ret < 0)) {
  91                printk(KERN_ERR MODNAME ": IRQ %d request failed\n",
  92                       HP680_BTN_IRQ);
  93                return ret;
  94        }
  95
  96        apm_get_power_status = hp6x0_apm_get_power_status;
  97
  98        return ret;
  99}
 100
 101static void __exit hp6x0_apm_exit(void)
 102{
 103        free_irq(HP680_BTN_IRQ, 0);
 104}
 105
 106module_init(hp6x0_apm_init);
 107module_exit(hp6x0_apm_exit);
 108
 109MODULE_AUTHOR("Adriy Skulysh");
 110MODULE_DESCRIPTION("hp6xx Advanced Power Management");
 111MODULE_LICENSE("GPL");
 112