1// SPDX-License-Identifier: GPL-2.0
2/*
3 * bios-less APM driver for hp680
4 *
5 * Copyright 2005 (c) Andriy Skulysh <askulysh@gmail.com>
6 * Copyright 2008 (c) Kristoffer Ericson <kristoffer.ericson@gmail.com>
7 */
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/interrupt.h>
12#include <linux/apm-emulation.h>
13#include <linux/io.h>
14#include <asm/adc.h>
15#include <mach/hp6xx.h>
16
17/* percentage values */
18#define APM_CRITICAL			10
19#define APM_LOW				30
20
21/* resonably sane values */
22#define HP680_BATTERY_MAX		898
23#define HP680_BATTERY_MIN		486
24#define HP680_BATTERY_AC_ON		1023
25
26#define MODNAME "hp6x0_apm"
27
28#define PGDR	0xa400012c
29
30static void hp6x0_apm_get_power_status(struct apm_power_info *info)
31{
32	int battery, backup, charging, percentage;
33	u8 pgdr;
34
35	battery		= adc_single(ADC_CHANNEL_BATTERY);
36	backup		= adc_single(ADC_CHANNEL_BACKUP);
37	charging	= adc_single(ADC_CHANNEL_CHARGE);
38
39	percentage = 100 * (battery - HP680_BATTERY_MIN) /
40			   (HP680_BATTERY_MAX - HP680_BATTERY_MIN);
41
42	/* % of full battery */
43	info->battery_life = percentage;
44
45	/* We want our estimates in minutes */
46	info->units = 0;
47
48	/* Extremely(!!) rough estimate, we will replace this with a datalist later on */
49	info->time = (2 * battery);
50
51	info->ac_line_status = (battery > HP680_BATTERY_AC_ON) ?
52			 APM_AC_ONLINE : APM_AC_OFFLINE;
53
54	pgdr = __raw_readb(PGDR);
55	if (pgdr & PGDR_MAIN_BATTERY_OUT) {
56		info->battery_status	= APM_BATTERY_STATUS_NOT_PRESENT;
57		info->battery_flag	= 0x80;
58	} else if (charging < 8) {
59		info->battery_status	= APM_BATTERY_STATUS_CHARGING;
60		info->battery_flag	= 0x08;
61		info->ac_line_status	= 0x01;
62	} else if (percentage <= APM_CRITICAL) {
63		info->battery_status	= APM_BATTERY_STATUS_CRITICAL;
64		info->battery_flag	= 0x04;
65	} else if (percentage <= APM_LOW) {
66		info->battery_status	= APM_BATTERY_STATUS_LOW;
67		info->battery_flag	= 0x02;
68	} else {
69		info->battery_status	= APM_BATTERY_STATUS_HIGH;
70		info->battery_flag	= 0x01;
71	}
72}
73
74static irqreturn_t hp6x0_apm_interrupt(int irq, void *dev)
75{
76	if (!APM_DISABLED)
77		apm_queue_event(APM_USER_SUSPEND);
78
79	return IRQ_HANDLED;
80}
81
82static int __init hp6x0_apm_init(void)
83{
84	int ret;
85
86	ret = request_irq(HP680_BTN_IRQ, hp6x0_apm_interrupt,
87			  0, MODNAME, NULL);
88	if (unlikely(ret < 0)) {
89		printk(KERN_ERR MODNAME ": IRQ %d request failed\n",
90		       HP680_BTN_IRQ);
91		return ret;
92	}
93
94	apm_get_power_status = hp6x0_apm_get_power_status;
95
96	return ret;
97}
98
99static void __exit hp6x0_apm_exit(void)
100{
101	free_irq(HP680_BTN_IRQ, 0);
102}
103
104module_init(hp6x0_apm_init);
105module_exit(hp6x0_apm_exit);
106
107MODULE_AUTHOR("Adriy Skulysh");
108MODULE_DESCRIPTION("hp6xx Advanced Power Management");
109MODULE_LICENSE("GPL");
110