sharpsl_pm.c

linux 内核源代码

/*
 * Battery and Power Management code for the Sharp SL-C7xx and SL-Cxx00
 * series of PDAs
 *
 * Copyright (c) 2004-2005 Richard Purdie
 *
 * Based on code written by Sharp for 2.4 kernels
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#undef DEBUG

#include <linux/module.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/apm_bios.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/apm-emulation.h>
#include <linux/suspend.h>

#include <asm/hardware.h>
#include <asm/mach-types.h>
#include <asm/irq.h>
#include <asm/arch/pm.h>
#include <asm/arch/pxa-regs.h>
#include <asm/arch/sharpsl.h>
#include <asm/hardware/sharpsl_pm.h>

/*
 * Constants
 */
#define SHARPSL_CHARGE_ON_TIME_INTERVAL        (msecs_to_jiffies(1*60*1000))  /* 1 min */
#define SHARPSL_CHARGE_FINISH_TIME             (msecs_to_jiffies(10*60*1000)) /* 10 min */
#define SHARPSL_BATCHK_TIME                    (msecs_to_jiffies(15*1000))    /* 15 sec */
#define SHARPSL_BATCHK_TIME_SUSPEND            (60*10)                        /* 10 min */

#define SHARPSL_WAIT_CO_TIME                   15  /* 15 sec */
#define SHARPSL_WAIT_DISCHARGE_ON              100 /* 100 msec */
#define SHARPSL_CHECK_BATTERY_WAIT_TIME_TEMP   10  /* 10 msec */
#define SHARPSL_CHECK_BATTERY_WAIT_TIME_VOLT   10  /* 10 msec */
#define SHARPSL_CHECK_BATTERY_WAIT_TIME_ACIN   10  /* 10 msec */
#define SHARPSL_CHARGE_WAIT_TIME               15  /* 15 msec */
#define SHARPSL_CHARGE_CO_CHECK_TIME           5   /* 5 msec */
#define SHARPSL_CHARGE_RETRY_CNT               1   /* eqv. 10 min */

/*
 * Prototypes
 */
static int sharpsl_off_charge_battery(void);
static int sharpsl_check_battery_temp(void);
static int sharpsl_check_battery_voltage(void);
static int sharpsl_ac_check(void);
static int sharpsl_fatal_check(void);
static int sharpsl_average_value(int ad);
static void sharpsl_average_clear(void);
static void sharpsl_charge_toggle(struct work_struct *private_);
static void sharpsl_battery_thread(struct work_struct *private_);


/*
 * Variables
 */
struct sharpsl_pm_status sharpsl_pm;
DECLARE_DELAYED_WORK(toggle_charger, sharpsl_charge_toggle);
DECLARE_DELAYED_WORK(sharpsl_bat, sharpsl_battery_thread);
DEFINE_LED_TRIGGER(sharpsl_charge_led_trigger);


static int get_percentage(int voltage)
{
	int i = sharpsl_pm.machinfo->bat_levels - 1;
	int bl_status = sharpsl_pm.machinfo->backlight_get_status ? sharpsl_pm.machinfo->backlight_get_status() : 0;
	struct battery_thresh *thresh;

	if (sharpsl_pm.charge_mode == CHRG_ON)
		thresh = bl_status ? sharpsl_pm.machinfo->bat_levels_acin_bl : sharpsl_pm.machinfo->bat_levels_acin;
	else
		thresh = bl_status ? sharpsl_pm.machinfo->bat_levels_noac_bl : sharpsl_pm.machinfo->bat_levels_noac;

	while (i > 0 && (voltage > thresh[i].voltage))
		i--;

	return thresh[i].percentage;
}

static int get_apm_status(int voltage)
{
	int low_thresh, high_thresh;

	if (sharpsl_pm.charge_mode == CHRG_ON) {
		high_thresh = sharpsl_pm.machinfo->status_high_acin;
		low_thresh = sharpsl_pm.machinfo->status_low_acin;
	} else {
		high_thresh = sharpsl_pm.machinfo->status_high_noac;
		low_thresh = sharpsl_pm.machinfo->status_low_noac;
	}

	if (voltage >= high_thresh)
		return APM_BATTERY_STATUS_HIGH;
	if (voltage >= low_thresh)
		return APM_BATTERY_STATUS_LOW;
	return APM_BATTERY_STATUS_CRITICAL;
}

void sharpsl_battery_kick(void)
{
	schedule_delayed_work(&sharpsl_bat, msecs_to_jiffies(125));
}
EXPORT_SYMBOL(sharpsl_battery_kick);


static void sharpsl_battery_thread(struct work_struct *private_)
{
	int voltage, percent, apm_status, i = 0;

	if (!sharpsl_pm.machinfo)
		return;

	sharpsl_pm.battstat.ac_status = (sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_ACIN) ? APM_AC_ONLINE : APM_AC_OFFLINE);

	/* Corgi cannot confirm when battery fully charged so periodically kick! */
	if (!sharpsl_pm.machinfo->batfull_irq && (sharpsl_pm.charge_mode == CHRG_ON)
			&& time_after(jiffies, sharpsl_pm.charge_start_time +  SHARPSL_CHARGE_ON_TIME_INTERVAL))
		schedule_delayed_work(&toggle_charger, 0);

	while(1) {
		voltage = sharpsl_pm.machinfo->read_devdata(SHARPSL_BATT_VOLT);

		if (voltage > 0) break;
		if (i++ > 5) {
			voltage = sharpsl_pm.machinfo->bat_levels_noac[0].voltage;
			dev_warn(sharpsl_pm.dev, "Warning: Cannot read main battery!\n");
			break;
		}
	}

	voltage = sharpsl_average_value(voltage);
	apm_status = get_apm_status(voltage);
	percent = get_percentage(voltage);

	/* At low battery voltages, the voltage has a tendency to start
           creeping back up so we try to avoid this here */
	if ((sharpsl_pm.battstat.ac_status == APM_AC_ONLINE) || (apm_status == APM_BATTERY_STATUS_HIGH) ||  percent <= sharpsl_pm.battstat.mainbat_percent) {
		sharpsl_pm.battstat.mainbat_voltage = voltage;
		sharpsl_pm.battstat.mainbat_status = apm_status;
		sharpsl_pm.battstat.mainbat_percent = percent;
	}

	dev_dbg(sharpsl_pm.dev, "Battery: voltage: %d, status: %d, percentage: %d, time: %ld\n", voltage,
			sharpsl_pm.battstat.mainbat_status, sharpsl_pm.battstat.mainbat_percent, jiffies);

	/* If battery is low. limit backlight intensity to save power. */
	if ((sharpsl_pm.battstat.ac_status != APM_AC_ONLINE)
			&& ((sharpsl_pm.battstat.mainbat_status == APM_BATTERY_STATUS_LOW) ||
			(sharpsl_pm.battstat.mainbat_status == APM_BATTERY_STATUS_CRITICAL))) {
		if (!(sharpsl_pm.flags & SHARPSL_BL_LIMIT)) {
			sharpsl_pm.machinfo->backlight_limit(1);
			sharpsl_pm.flags |= SHARPSL_BL_LIMIT;
		}
	} else if (sharpsl_pm.flags & SHARPSL_BL_LIMIT) {
		sharpsl_pm.machinfo->backlight_limit(0);
		sharpsl_pm.flags &= ~SHARPSL_BL_LIMIT;
	}

	/* Suspend if critical battery level */
	if ((sharpsl_pm.battstat.ac_status != APM_AC_ONLINE)
			&& (sharpsl_pm.battstat.mainbat_status == APM_BATTERY_STATUS_CRITICAL)
			&& !(sharpsl_pm.flags & SHARPSL_APM_QUEUED)) {
		sharpsl_pm.flags |= SHARPSL_APM_QUEUED;
		dev_err(sharpsl_pm.dev, "Fatal Off\n");
		apm_queue_event(APM_CRITICAL_SUSPEND);
	}

	schedule_delayed_work(&sharpsl_bat, SHARPSL_BATCHK_TIME);
}

void sharpsl_pm_led(int val)
{
	if (val == SHARPSL_LED_ERROR) {
		dev_err(sharpsl_pm.dev, "Charging Error!\n");
	} else if (val == SHARPSL_LED_ON) {
		dev_dbg(sharpsl_pm.dev, "Charge LED On\n");
		led_trigger_event(sharpsl_charge_led_trigger, LED_FULL);
	} else {
		dev_dbg(sharpsl_pm.dev, "Charge LED Off\n");
		led_trigger_event(sharpsl_charge_led_trigger, LED_OFF);
	}
}

static void sharpsl_charge_on(void)
{
	dev_dbg(sharpsl_pm.dev, "Turning Charger On\n");

	sharpsl_pm.full_count = 0;
	sharpsl_pm.charge_mode = CHRG_ON;
	schedule_delayed_work(&toggle_charger, msecs_to_jiffies(250));
	schedule_delayed_work(&sharpsl_bat, msecs_to_jiffies(500));
}

static void sharpsl_charge_off(void)
{
	dev_dbg(sharpsl_pm.dev, "Turning Charger Off\n");

	sharpsl_pm.machinfo->charge(0);
	sharpsl_pm_led(SHARPSL_LED_OFF);
	sharpsl_pm.charge_mode = CHRG_OFF;

	schedule_delayed_work(&sharpsl_bat, 0);
}

static void sharpsl_charge_error(void)
{
	sharpsl_pm_led(SHARPSL_LED_ERROR);
	sharpsl_pm.machinfo->charge(0);
	sharpsl_pm.charge_mode = CHRG_ERROR;
}

static void sharpsl_charge_toggle(struct work_struct *private_)
{
	dev_dbg(sharpsl_pm.dev, "Toogling Charger at time: %lx\n", jiffies);

	if (!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_ACIN)) {
		sharpsl_charge_off();
		return;
	} else if ((sharpsl_check_battery_temp() < 0) || (sharpsl_ac_check() < 0)) {
		sharpsl_charge_error();
		return;
	}

	sharpsl_pm_led(SHARPSL_LED_ON);
	sharpsl_pm.machinfo->charge(0);
	mdelay(SHARPSL_CHARGE_WAIT_TIME);
	sharpsl_pm.machinfo->charge(1);

	sharpsl_pm.charge_start_time = jiffies;
}

static void sharpsl_ac_timer(unsigned long data)
{
	int acin = sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_ACIN);

	dev_dbg(sharpsl_pm.dev, "AC Status: %d\n",acin);

	sharpsl_average_clear();
	if (acin && (sharpsl_pm.charge_mode != CHRG_ON))
		sharpsl_charge_on();
	else if (sharpsl_pm.charge_mode == CHRG_ON)
		sharpsl_charge_off();

	schedule_delayed_work(&sharpsl_bat, 0);
}


irqreturn_t sharpsl_ac_isr(int irq, void *dev_id)
{
	/* Delay the event slightly to debounce */
	/* Must be a smaller delay than the chrg_full_isr below */
	mod_timer(&sharpsl_pm.ac_timer, jiffies + msecs_to_jiffies(250));

	return IRQ_HANDLED;
}

static void sharpsl_chrg_full_timer(unsigned long data)
{
	dev_dbg(sharpsl_pm.dev, "Charge Full at time: %lx\n", jiffies);

	sharpsl_pm.full_count++;

	if (!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_ACIN)) {
		dev_dbg(sharpsl_pm.dev, "Charge Full: AC removed - stop charging!\n");
		if (sharpsl_pm.charge_mode == CHRG_ON)
			sharpsl_charge_off();
	} else if (sharpsl_pm.full_count < 2) {
		dev_dbg(sharpsl_pm.dev, "Charge Full: Count too low\n");
		schedule_delayed_work(&toggle_charger, 0);
	} else if (time_after(jiffies, sharpsl_pm.charge_start_time + SHARPSL_CHARGE_FINISH_TIME)) {
		dev_dbg(sharpsl_pm.dev, "Charge Full: Interrupt generated too slowly - retry.\n");
		schedule_delayed_work(&toggle_charger, 0);
	} else {
		sharpsl_charge_off();
		sharpsl_pm.charge_mode = CHRG_DONE;
		dev_dbg(sharpsl_pm.dev, "Charge Full: Charging Finished\n");
	}
}

/* Charging Finished Interrupt (Not present on Corgi) */
/* Can trigger at the same time as an AC status change so
   delay until after that has been processed */
irqreturn_t sharpsl_chrg_full_isr(int irq, void *dev_id)
{
	if (sharpsl_pm.flags & SHARPSL_SUSPENDED)
		return IRQ_HANDLED;

	/* delay until after any ac interrupt */
	mod_timer(&sharpsl_pm.chrg_full_timer, jiffies + msecs_to_jiffies(500));

	return IRQ_HANDLED;
}

irqreturn_t sharpsl_fatal_isr(int irq, void *dev_id)
{
	int is_fatal = 0;

	if (!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_LOCK)) {
		dev_err(sharpsl_pm.dev, "Battery now Unlocked! Suspending.\n");
		is_fatal = 1;
	}

	if (!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_FATAL)) {
		dev_err(sharpsl_pm.dev, "Fatal Batt Error! Suspending.\n");
		is_fatal = 1;
	}

	if (!(sharpsl_pm.flags & SHARPSL_APM_QUEUED) && is_fatal) {
		sharpsl_pm.flags |= SHARPSL_APM_QUEUED;
		apm_queue_event(APM_CRITICAL_SUSPEND);
	}

	return IRQ_HANDLED;
}

/*
 * Maintain an average of the last 10 readings
 */
#define SHARPSL_CNV_VALUE_NUM    10
static int sharpsl_ad_index;

static void sharpsl_average_clear(void)
{
	sharpsl_ad_index = 0;
}

static int sharpsl_average_value(int ad)
{
	int i, ad_val = 0;
	static int sharpsl_ad[SHARPSL_CNV_VALUE_NUM+1];

	if (sharpsl_pm.battstat.mainbat_status != APM_BATTERY_STATUS_HIGH) {
		sharpsl_ad_index = 0;
		return ad;
	}

	sharpsl_ad[sharpsl_ad_index] = ad;
	sharpsl_ad_index++;
	if (sharpsl_ad_index >= SHARPSL_CNV_VALUE_NUM) {
		for (i=0; i < (SHARPSL_CNV_VALUE_NUM-1); i++)
			sharpsl_ad[i] = sharpsl_ad[i+1];
		sharpsl_ad_index = SHARPSL_CNV_VALUE_NUM - 1;
	}
	for (i=0; i < sharpsl_ad_index; i++)
		ad_val += sharpsl_ad[i];

	return (ad_val / sharpsl_ad_index);
}

/*
 * Take an array of 5 integers, remove the maximum and minimum values
 * and return the average.
 */
static int get_select_val(int *val)
{
	int i, j, k, temp, sum = 0;

	/* Find MAX val */
	temp = val[0];
	j=0;
	for (i=1; i<5; i++) {
		if (temp < val[i]) {
			temp = val[i];
			j = i;
		}
	}

	/* Find MIN val */
	temp = val[4];
	k=4;
	for (i=3; i>=0; i--) {
		if (temp > val[i]) {
			temp = val[i];
			k = i;
		}
	}

	for (i=0; i<5; i++)
		if (i != j && i != k )
			sum += val[i];

	dev_dbg(sharpsl_pm.dev, "Average: %d from values: %d, %d, %d, %d, %d\n", sum/3, val[0], val[1], val[2], val[3], val[4]);

	return (sum/3);
}

static int sharpsl_check_battery_temp(void)
{
	int val, i, buff[5];

	/* Check battery temperature */
	for (i=0; i<5; i++) {
		mdelay(SHARPSL_CHECK_BATTERY_WAIT_TIME_TEMP);
		sharpsl_pm.machinfo->measure_temp(1);
		mdelay(SHARPSL_CHECK_BATTERY_WAIT_TIME_TEMP);
		buff[i] = sharpsl_pm.machinfo->read_devdata(SHARPSL_BATT_TEMP);
		sharpsl_pm.machinfo->measure_temp(0);
	}

	val = get_select_val(buff);

	dev_dbg(sharpsl_pm.dev, "Temperature: %d\n", val);
	if (val > sharpsl_pm.machinfo->charge_on_temp) {
		printk(KERN_WARNING "Not charging: temperature out of limits.\n");
		return -1;
	}

	return 0;
}

static int sharpsl_check_battery_voltage(void)