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
28static 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
97static 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
106static 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
114module_init(apm_emu_init);
115module_exit(apm_emu_exit);
116
117MODULE_AUTHOR("Benjamin Herrenschmidt");
118MODULE_DESCRIPTION("APM emulation for PowerMac");
119MODULE_LICENSE("GPL");
120