drivers/macintosh/apm_emu.c

   1 /*
   2  * APM emulation for PMU-based machines
   3  *
   4  * Copyright 2001 Benjamin Herrenschmidt (benh@kernel.crashing.org)
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  *
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/apm-emulation.h>
  22 #include <linux/adb.h>
  23 #include <linux/pmu.h>
  24
  25 #define APM_CRITICAL            10
  26 #define APM_LOW                 30
  27
  28 static void pmu_apm_get_power_status(struct apm_power_info *info)
  29 {
  30         int percentage = -1;
  31         int batteries = 0;
  32         int time_units = -1;
  33         int real_count = 0;
  34         int i;
  35         char charging = 0;
  36         long charge = -1;
  37         long amperage = 0;
  38         unsigned long btype = 0;
  39
  40         info->battery_status = APM_BATTERY_STATUS_UNKNOWN;
  41         info->battery_flag = APM_BATTERY_FLAG_UNKNOWN;
  42         info->units = APM_UNITS_MINS;
  43
  44         if (pmu_power_flags & PMU_PWR_AC_PRESENT)
  45                 info->ac_line_status = APM_AC_ONLINE;
  46         else
  47                 info->ac_line_status = APM_AC_OFFLINE;
  48
  49         for (i=0; i<pmu_battery_count; i++) {
  50                 if (pmu_batteries[i].flags & PMU_BATT_PRESENT) {
  51                         batteries++;
  52                         if (percentage < 0)
  53                                 percentage = 0;
  54                         if (charge < 0)
  55                                 charge = 0;
  56                         percentage += (pmu_batteries[i].charge * 100) /
  57                                 pmu_batteries[i].max_charge;
  58                         charge += pmu_batteries[i].charge;
  59                         amperage += pmu_batteries[i].amperage;
  60                         if (btype == 0)
  61                                 btype = (pmu_batteries[i].flags & PMU_BATT_TYPE_MASK);
  62                         real_count++;
  63                         if ((pmu_batteries[i].flags & PMU_BATT_CHARGING))
  64                                 charging++;
  65                 }
  66         }
  67         if (batteries == 0)
  68                 info->ac_line_status = APM_AC_ONLINE;
  69
  70         if (real_count) {
  71                 if (amperage < 0) {
  72                         if (btype == PMU_BATT_TYPE_SMART)
  73                                 time_units = (charge * 59) / (amperage * -1);
  74                         else
  75                                 time_units = (charge * 16440) / (amperage * -60);
  76                 }
  77                 percentage /= real_count;
  78                 if (charging > 0) {
  79                         info->battery_status = APM_BATTERY_STATUS_CHARGING;
  80                         info->battery_flag = APM_BATTERY_FLAG_CHARGING;
  81                 } else if (percentage <= APM_CRITICAL) {
  82                         info->battery_status = APM_BATTERY_STATUS_CRITICAL;
  83                         info->battery_flag = APM_BATTERY_FLAG_CRITICAL;
  84                 } else if (percentage <= APM_LOW) {
  85                         info->battery_status = APM_BATTERY_STATUS_LOW;
  86                         info->battery_flag = APM_BATTERY_FLAG_LOW;
  87                 } else {
  88                         info->battery_status = APM_BATTERY_STATUS_HIGH;
  89                         info->battery_flag = APM_BATTERY_FLAG_HIGH;
  90                 }
  91         }
  92
  93         info->battery_life = percentage;
  94         info->time = time_units;
  95 }
  96
  97 static int __init apm_emu_init(void)
  98 {
  99         apm_get_power_status = pmu_apm_get_power_status;
 100
 101         printk(KERN_INFO "apm_emu: PMU APM Emulation initialized.\n");
 102
 103         return 0;
 104 }
 105
 106 static void __exit apm_emu_exit(void)
 107 {
 108         if (apm_get_power_status == pmu_apm_get_power_status)
 109                 apm_get_power_status = NULL;
 110
 111         printk(KERN_INFO "apm_emu: PMU APM Emulation removed.\n");
 112 }
 113
 114 module_init(apm_emu_init);
 115 module_exit(apm_emu_exit);
 116
 117 MODULE_AUTHOR("Benjamin Herrenschmidt");
 118 MODULE_DESCRIPTION("APM emulation for PowerMac");
 119 MODULE_LICENSE("GPL");