Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linux
[linux-2.6] / arch / sh / boards / mach-hp6xx / hp6xx_apm.c
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
32 static 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 = ctrl_inb(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
76 static 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
84 static int __init hp6x0_apm_init(void)
85 {
86         int ret;
87
88         ret = request_irq(HP680_BTN_IRQ, hp6x0_apm_interrupt,
89                           IRQF_DISABLED, 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
101 static void __exit hp6x0_apm_exit(void)
102 {
103         free_irq(HP680_BTN_IRQ, 0);
104 }
105
106 module_init(hp6x0_apm_init);
107 module_exit(hp6x0_apm_exit);
108
109 MODULE_AUTHOR("Adriy Skulysh");
110 MODULE_DESCRIPTION("hp6xx Advanced Power Management");
111 MODULE_LICENSE("GPL");