arch/sh/boards/hp6xx/hp6xx_apm.c

   1 /*
   2  * bios-less APM driver for hp680
   3  *
   4  * Copyright 2005 (c) Andriy Skulysh <askulysh@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License.
   8  */
   9 #include <linux/module.h>
  10 #include <linux/apm_bios.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/interrupt.h>
  14 #include <asm/io.h>
  15 #include <asm/apm.h>
  16 #include <asm/adc.h>
  17 #include <asm/hp6xx.h>
  18
  19 #define SH7709_PGDR                     0xa400012c
  20
  21 #define APM_CRITICAL                    10
  22 #define APM_LOW                         30
  23
  24 #define HP680_BATTERY_MAX               875
  25 #define HP680_BATTERY_MIN               600
  26 #define HP680_BATTERY_AC_ON             900
  27
  28 #define MODNAME "hp6x0_apm"
  29
  30 static int hp6x0_apm_get_info(char *buf, char **start, off_t fpos, int length)
  31 {
  32         u8 pgdr;
  33         char *p;
  34         int battery_status;
  35         int battery_flag;
  36         int ac_line_status;
  37         int time_units = APM_BATTERY_LIFE_UNKNOWN;
  38
  39         int battery = adc_single(ADC_CHANNEL_BATTERY);
  40         int backup = adc_single(ADC_CHANNEL_BACKUP);
  41         int charging = adc_single(ADC_CHANNEL_CHARGE);
  42         int percentage;
  43
  44         percentage = 100 * (battery - HP680_BATTERY_MIN) /
  45                            (HP680_BATTERY_MAX - HP680_BATTERY_MIN);
  46
  47         ac_line_status = (battery > HP680_BATTERY_AC_ON) ?
  48                          APM_AC_ONLINE : APM_AC_OFFLINE;
  49
  50         p = buf;
  51
  52         pgdr = ctrl_inb(SH7709_PGDR);
  53         if (pgdr & PGDR_MAIN_BATTERY_OUT) {
  54                 battery_status = APM_BATTERY_STATUS_NOT_PRESENT;
  55                 battery_flag = 0x80;
  56                 percentage = -1;
  57         } else if (charging < 8 ) {
  58                 battery_status = APM_BATTERY_STATUS_CHARGING;
  59                 battery_flag = 0x08;
  60                 ac_line_status = 0xff;
  61         } else if (percentage <= APM_CRITICAL) {
  62                 battery_status = APM_BATTERY_STATUS_CRITICAL;
  63                 battery_flag = 0x04;
  64         } else if (percentage <= APM_LOW) {
  65                 battery_status = APM_BATTERY_STATUS_LOW;
  66                 battery_flag = 0x02;
  67         } else {
  68                 battery_status = APM_BATTERY_STATUS_HIGH;
  69                 battery_flag = 0x01;
  70         }
  71
  72         p += sprintf(p, "1.0 1.2 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
  73                      APM_32_BIT_SUPPORT,
  74                      ac_line_status,
  75                      battery_status,
  76                      battery_flag,
  77                      percentage,
  78                      time_units,
  79                      "min");
  80         p += sprintf(p, "bat=%d backup=%d charge=%d\n",
  81                      battery, backup, charging);
  82
  83         return p - buf;
  84 }
  85
  86 static irqreturn_t hp6x0_apm_interrupt(int irq, void *dev)
  87 {
  88         if (!apm_suspended)
  89                 apm_queue_event(APM_USER_SUSPEND);
  90
  91         return IRQ_HANDLED;
  92 }
  93
  94 static int __init hp6x0_apm_init(void)
  95 {
  96         int ret;
  97
  98         ret = request_irq(HP680_BTN_IRQ, hp6x0_apm_interrupt,
  99                           IRQF_DISABLED, MODNAME, 0);
 100         if (unlikely(ret < 0)) {
 101                 printk(KERN_ERR MODNAME ": IRQ %d request failed\n",
 102                        HP680_BTN_IRQ);
 103                 return ret;
 104         }
 105
 106         apm_get_info = hp6x0_apm_get_info;
 107
 108         return ret;
 109 }
 110
 111 static void __exit hp6x0_apm_exit(void)
 112 {
 113         free_irq(HP680_BTN_IRQ, 0);
 114         apm_get_info = 0;
 115 }
 116
 117 module_init(hp6x0_apm_init);
 118 module_exit(hp6x0_apm_exit);
 119
 120 MODULE_AUTHOR("Adriy Skulysh");
 121 MODULE_DESCRIPTION("hp6xx Advanced Power Management");
 122 MODULE_LICENSE("GPL");