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
30 static 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
74 static 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
82 static 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
99 static void __exit hp6x0_apm_exit(void)
100 {
101 free_irq(HP680_BTN_IRQ, 0);
102 }
103
104 module_init(hp6x0_apm_init);
105 module_exit(hp6x0_apm_exit);
106
107 MODULE_AUTHOR("Adriy Skulysh");
108 MODULE_DESCRIPTION("hp6xx Advanced Power Management");
109 MODULE_LICENSE("GPL");
110
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