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