sharpsl_pm.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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
 */

#undef DEBUG

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

#include <asm/mach-types.h>
#include "pm.h"
#include "pxa2xx-regs.h"
#include "regs-rtc.h"
#include "sharpsl_pm.h"

/*
 * Constants
 */
#define SHARPSL_CHARGE_ON_TIME_INTERVAL        (secs_to_jiffies(60))
#define SHARPSL_CHARGE_FINISH_TIME             (secs_to_jiffies(10*60))
#define SHARPSL_BATCHK_TIME                    (secs_to_jiffies(15))
#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
 */
#ifdef CONFIG_PM
static int sharpsl_off_charge_battery(void);
static int sharpsl_check_battery_voltage(void);
#endif
static int sharpsl_check_battery_temp(void);
static int sharpsl_ac_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;
static DECLARE_DELAYED_WORK(toggle_charger, sharpsl_charge_toggle);
static DECLARE_DELAYED_WORK(sharpsl_bat, sharpsl_battery_thread);
DEFINE_LED_TRIGGER(sharpsl_charge_led_trigger);



struct battery_thresh sharpsl_battery_levels_acin[] = {
	{ 213, 100},
	{ 212,  98},
	{ 211,  95},
	{ 210,  93},
	{ 209,  90},
	{ 208,  88},
	{ 207,  85},
	{ 206,  83},
	{ 205,  80},
	{ 204,  78},
	{ 203,  75},
	{ 202,  73},
	{ 201,  70},
	{ 200,  68},
	{ 199,  65},
	{ 198,  63},
	{ 197,  60},
	{ 196,  58},
	{ 195,  55},
	{ 194,  53},
	{ 193,  50},
	{ 192,  48},
	{ 192,  45},
	{ 191,  43},
	{ 191,  40},
	{ 190,  38},
	{ 190,  35},
	{ 189,  33},
	{ 188,  30},
	{ 187,  28},
	{ 186,  25},
	{ 185,  23},
	{ 184,  20},
	{ 183,  18},
	{ 182,  15},
	{ 181,  13},
	{ 180,  10},
	{ 179,   8},
	{ 178,   5},
	{   0,   0},
};

struct battery_thresh sharpsl_battery_levels_noac[] = {
	{ 213, 100},
	{ 212,  98},
	{ 211,  95},
	{ 210,  93},
	{ 209,  90},
	{ 208,  88},
	{ 207,  85},
	{ 206,  83},
	{ 205,  80},
	{ 204,  78},
	{ 203,  75},
	{ 202,  73},
	{ 201,  70},
	{ 200,  68},
	{ 199,  65},
	{ 198,  63},
	{ 197,  60},
	{ 196,  58},
	{ 195,  55},
	{ 194,  53},
	{ 193,  50},
	{ 192,  48},
	{ 191,  45},
	{ 190,  43},
	{ 189,  40},
	{ 188,  38},
	{ 187,  35},
	{ 186,  33},
	{ 185,  30},
	{ 184,  28},
	{ 183,  25},
	{ 182,  23},
	{ 181,  20},
	{ 180,  18},
	{ 179,  15},
	{ 178,  13},
	{ 177,  10},
	{ 176,   8},
	{ 175,   5},
	{   0,   0},
};

/* MAX1111 Commands */
#define MAXCTRL_PD0      (1u << 0)
#define MAXCTRL_PD1      (1u << 1)
#define MAXCTRL_SGL      (1u << 2)
#define MAXCTRL_UNI      (1u << 3)
#define MAXCTRL_SEL_SH   4
#define MAXCTRL_STR      (1u << 7)

extern int max1111_read_channel(int);
/*
 * Read MAX1111 ADC
 */
int sharpsl_pm_pxa_read_max1111(int channel)
{
	/* max1111 accepts channels from 0-3, however,
	 * it is encoded from 0-7 here in the code.
	 */
	return max1111_read_channel(channel >> 1);
}

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));
}

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

	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);

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

	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);

	/* 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, "Toggling 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(struct timer_list *unused)
{
	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);
}


static 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(struct timer_list *unused)
{
	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 */
static 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;
}

static 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;
}

#ifdef CONFIG_PM
static int sharpsl_check_battery_voltage(void)
{
	int val, i, buff[5];

	/* disable charge, enable discharge */
	sharpsl_pm.machinfo->charge(0);
	sharpsl_pm.machinfo->discharge(1);
	mdelay(SHARPSL_WAIT_DISCHARGE_ON);

	if (sharpsl_pm.machinfo->discharge1)
		sharpsl_pm.machinfo->discharge1(1);

	/* Check battery voltage */
	for (i = 0; i < 5; i++) {
		buff[i] = sharpsl_pm.machinfo->read_devdata(SHARPSL_BATT_VOLT);
		mdelay(SHARPSL_CHECK_BATTERY_WAIT_TIME_VOLT);
	}

	if (sharpsl_pm.machinfo->discharge1)
		sharpsl_pm.machinfo->discharge1(0);

	sharpsl_pm.machinfo->discharge(0);

	val = get_select_val(buff);
	dev_dbg(sharpsl_pm.dev, "Battery Voltage: %d\n", val);

	if (val < sharpsl_pm.machinfo->charge_on_volt)
		return -1;

	return 0;
}
#endif

static int sharpsl_ac_check(void)
{
	int temp, i, buff[5];

	for (i = 0; i < 5; i++) {
		buff[i] = sharpsl_pm.machinfo->read_devdata(SHARPSL_ACIN_VOLT);
		mdelay(SHARPSL_CHECK_BATTERY_WAIT_TIME_ACIN);
	}

	temp = get_select_val(buff);
	dev_dbg(sharpsl_pm.dev, "AC Voltage: %d\n", temp);

	if ((temp > sharpsl_pm.machinfo->charge_acin_high) || (temp < sharpsl_pm.machinfo->charge_acin_low)) {
		dev_err(sharpsl_pm.dev, "Error: AC check failed: voltage %d.\n", temp);
		return -1;
	}

	return 0;
}

#ifdef CONFIG_PM
static int sharpsl_pm_suspend(struct platform_device *pdev, pm_message_t state)
{
	sharpsl_pm.flags |= SHARPSL_SUSPENDED;
	flush_delayed_work(&toggle_charger);
	flush_delayed_work(&sharpsl_bat);

	if (sharpsl_pm.charge_mode == CHRG_ON)
		sharpsl_pm.flags |= SHARPSL_DO_OFFLINE_CHRG;
	else
		sharpsl_pm.flags &= ~SHARPSL_DO_OFFLINE_CHRG;

	return 0;
}

static int sharpsl_pm_resume(struct platform_device *pdev)
{
	/* Clear the reset source indicators as they break the bootloader upon reboot */
	RCSR = 0x0f;
	sharpsl_average_clear();
	sharpsl_pm.flags &= ~SHARPSL_APM_QUEUED;
	sharpsl_pm.flags &= ~SHARPSL_SUSPENDED;

	return 0;
}

static void corgi_goto_sleep(unsigned long alarm_time, unsigned int alarm_enable, suspend_state_t state)
{
	dev_dbg(sharpsl_pm.dev, "Time is: %08x\n", RCNR);

	dev_dbg(sharpsl_pm.dev, "Offline Charge Activate = %d\n", sharpsl_pm.flags & SHARPSL_DO_OFFLINE_CHRG);
	/* not charging and AC-IN! */

	if ((sharpsl_pm.flags & SHARPSL_DO_OFFLINE_CHRG) && (sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_ACIN))) {
		dev_dbg(sharpsl_pm.dev, "Activating Offline Charger...\n");
		sharpsl_pm.charge_mode = CHRG_OFF;
		sharpsl_pm.flags &= ~SHARPSL_DO_OFFLINE_CHRG;
		sharpsl_off_charge_battery();
	}

	sharpsl_pm.machinfo->presuspend();

	PEDR = 0xffffffff; /* clear it */

	sharpsl_pm.flags &= ~SHARPSL_ALARM_ACTIVE;
	if ((sharpsl_pm.charge_mode == CHRG_ON) && ((alarm_enable && ((alarm_time - RCNR) > (SHARPSL_BATCHK_TIME_SUSPEND + 30))) || !alarm_enable)) {
		RTSR &= RTSR_ALE;
		RTAR = RCNR + SHARPSL_BATCHK_TIME_SUSPEND;
		dev_dbg(sharpsl_pm.dev, "Charging alarm at: %08x\n", RTAR);
		sharpsl_pm.flags |= SHARPSL_ALARM_ACTIVE;
	} else if (alarm_enable) {
		RTSR &= RTSR_ALE;
		RTAR = alarm_time;
		dev_dbg(sharpsl_pm.dev, "User alarm at: %08x\n", RTAR);
	} else {
		dev_dbg(sharpsl_pm.dev, "No alarms set.\n");
	}

	pxa_pm_enter(state);

	sharpsl_pm.machinfo->postsuspend();

	dev_dbg(sharpsl_pm.dev, "Corgi woken up from suspend: %08x\n", PEDR);
}

static int corgi_enter_suspend(unsigned long alarm_time, unsigned int alarm_enable, suspend_state_t state)
{
	if (!sharpsl_pm.machinfo->should_wakeup(!(sharpsl_pm.flags & SHARPSL_ALARM_ACTIVE) && alarm_enable)) {
		if (!(sharpsl_pm.flags & SHARPSL_ALARM_ACTIVE)) {
			dev_dbg(sharpsl_pm.dev, "No user triggered wakeup events and not charging. Strange. Suspend.\n");
			corgi_goto_sleep(alarm_time, alarm_enable, state);
			return 1;
		}
		if (sharpsl_off_charge_battery()) {
			dev_dbg(sharpsl_pm.dev, "Charging. Suspend...\n");
			corgi_goto_sleep(alarm_time, alarm_enable, state);
			return 1;
		}
		dev_dbg(sharpsl_pm.dev, "User triggered wakeup in offline charger.\n");
	}

	if ((!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_LOCK)) ||
	    (!sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_FATAL)))	{
		dev_err(sharpsl_pm.dev, "Fatal condition. Suspend.\n");
		corgi_goto_sleep(alarm_time, alarm_enable, state);
		return 1;
	}

	return 0;
}

static int corgi_pxa_pm_enter(suspend_state_t state)
{
	unsigned long alarm_time = RTAR;
	unsigned int alarm_status = ((RTSR & RTSR_ALE) != 0);

	dev_dbg(sharpsl_pm.dev, "SharpSL suspending for first time.\n");

	corgi_goto_sleep(alarm_time, alarm_status, state);

	while (corgi_enter_suspend(alarm_time, alarm_status, state))
		{}

	if (sharpsl_pm.machinfo->earlyresume)
		sharpsl_pm.machinfo->earlyresume();

	dev_dbg(sharpsl_pm.dev, "SharpSL resuming...\n");

	return 0;
}

static int sharpsl_off_charge_error(void)
{
	dev_err(sharpsl_pm.dev, "Offline Charger: Error occurred.\n");
	sharpsl_pm.machinfo->charge(0);
	sharpsl_pm_led(SHARPSL_LED_ERROR);
	sharpsl_pm.charge_mode = CHRG_ERROR;
	return 1;
}

/*
 * Charging Control while suspended
 * Return 1 - go straight to sleep
 * Return 0 - sleep or wakeup depending on other factors
 */
static int sharpsl_off_charge_battery(void)
{
	int time;

	dev_dbg(sharpsl_pm.dev, "Charge Mode: %d\n", sharpsl_pm.charge_mode);

	if (sharpsl_pm.charge_mode == CHRG_OFF) {
		dev_dbg(sharpsl_pm.dev, "Offline Charger: Step 1\n");

		/* AC Check */
		if ((sharpsl_ac_check() < 0) || (sharpsl_check_battery_temp() < 0))
			return sharpsl_off_charge_error();

		/* Start Charging */
		sharpsl_pm_led(SHARPSL_LED_ON);
		sharpsl_pm.machinfo->charge(0);
		mdelay(SHARPSL_CHARGE_WAIT_TIME);
		sharpsl_pm.machinfo->charge(1);

		sharpsl_pm.charge_mode = CHRG_ON;
		sharpsl_pm.full_count = 0;

		return 1;
	} else if (sharpsl_pm.charge_mode != CHRG_ON) {
		return 1;
	}

	if (sharpsl_pm.full_count == 0) {
		int time;

		dev_dbg(sharpsl_pm.dev, "Offline Charger: Step 2\n");

		if ((sharpsl_check_battery_temp() < 0) || (sharpsl_check_battery_voltage() < 0))
			return sharpsl_off_charge_error();

		sharpsl_pm.machinfo->charge(0);
		mdelay(SHARPSL_CHARGE_WAIT_TIME);
		sharpsl_pm.machinfo->charge(1);
		sharpsl_pm.charge_mode = CHRG_ON;

		mdelay(SHARPSL_CHARGE_CO_CHECK_TIME);

		time = RCNR;
		while (1) {
			/* Check if any wakeup event had occurred */
			if (sharpsl_pm.machinfo->charger_wakeup())
				return 0;
			/* Check for timeout */
			if ((RCNR - time) > SHARPSL_WAIT_CO_TIME)
				return 1;
			if (sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_CHRGFULL)) {
				dev_dbg(sharpsl_pm.dev, "Offline Charger: Charge full occurred. Retrying to check\n");
				sharpsl_pm.full_count++;
				sharpsl_pm.machinfo->charge(0);
				mdelay(SHARPSL_CHARGE_WAIT_TIME);
				sharpsl_pm.machinfo->charge(1);
				return 1;
			}
		}
	}

	dev_dbg(sharpsl_pm.dev, "Offline Charger: Step 3\n");

	mdelay(SHARPSL_CHARGE_CO_CHECK_TIME);

	time = RCNR;
	while (1) {
		/* Check if any wakeup event had occurred */
		if (sharpsl_pm.machinfo->charger_wakeup())
			return 0;
		/* Check for timeout */
		if ((RCNR-time) > SHARPSL_WAIT_CO_TIME) {
			if (sharpsl_pm.full_count > SHARPSL_CHARGE_RETRY_CNT) {
				dev_dbg(sharpsl_pm.dev, "Offline Charger: Not charged sufficiently. Retrying.\n");
				sharpsl_pm.full_count = 0;
			}
			sharpsl_pm.full_count++;
			return 1;
		}
		if (sharpsl_pm.machinfo->read_devdata(SHARPSL_STATUS_CHRGFULL)) {
			dev_dbg(sharpsl_pm.dev, "Offline Charger: Charging complete.\n");
			sharpsl_pm_led(SHARPSL_LED_OFF);
			sharpsl_pm.machinfo->charge(0);
			sharpsl_pm.charge_mode = CHRG_DONE;
			return 1;
		}
	}
}
#else
#define sharpsl_pm_suspend	NULL
#define sharpsl_pm_resume	NULL
#endif

static ssize_t battery_percentage_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%d\n", sharpsl_pm.battstat.mainbat_percent);
}

static ssize_t battery_voltage_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%d\n", sharpsl_pm.battstat.mainbat_voltage);
}

static DEVICE_ATTR_RO(battery_percentage);
static DEVICE_ATTR_RO(battery_voltage);

extern void (*apm_get_power_status)(struct apm_power_info *);

static void sharpsl_apm_get_power_status(struct apm_power_info *info)
{
	info->ac_line_status = sharpsl_pm.battstat.ac_status;

	if (sharpsl_pm.charge_mode == CHRG_ON)
		info->battery_status = APM_BATTERY_STATUS_CHARGING;
	else
		info->battery_status = sharpsl_pm.battstat.mainbat_status;

	info->battery_flag = (1 << info->battery_status);
	info->battery_life = sharpsl_pm.battstat.mainbat_percent;
}

#ifdef CONFIG_PM
static const struct platform_suspend_ops sharpsl_pm_ops = {
	.prepare	= pxa_pm_prepare,
	.finish		= pxa_pm_finish,
	.enter		= corgi_pxa_pm_enter,
	.valid		= suspend_valid_only_mem,
};
#endif

static int sharpsl_pm_probe(struct platform_device *pdev)
{
	int ret, irq;

	if (!pdev->dev.platform_data)
		return -EINVAL;

	sharpsl_pm.dev = &pdev->dev;
	sharpsl_pm.machinfo = pdev->dev.platform_data;
	sharpsl_pm.charge_mode = CHRG_OFF;
	sharpsl_pm.flags = 0;

	timer_setup(&sharpsl_pm.ac_timer, sharpsl_ac_timer, 0);

	timer_setup(&sharpsl_pm.chrg_full_timer, sharpsl_chrg_full_timer, 0);

	led_trigger_register_simple("sharpsl-charge", &sharpsl_charge_led_trigger);

	sharpsl_pm.machinfo->init();

	gpio_request(sharpsl_pm.machinfo->gpio_acin, "AC IN");
	gpio_direction_input(sharpsl_pm.machinfo->gpio_acin);
	gpio_request(sharpsl_pm.machinfo->gpio_batfull, "Battery Full");
	gpio_direction_input(sharpsl_pm.machinfo->gpio_batfull);
	gpio_request(sharpsl_pm.machinfo->gpio_batlock, "Battery Lock");
	gpio_direction_input(sharpsl_pm.machinfo->gpio_batlock);

	/* Register interrupt handlers */
	irq = gpio_to_irq(sharpsl_pm.machinfo->gpio_acin);
	if (request_irq(irq, sharpsl_ac_isr, IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, "AC Input Detect", sharpsl_ac_isr)) {
		dev_err(sharpsl_pm.dev, "Could not get irq %d.\n", irq);
	}

	irq = gpio_to_irq(sharpsl_pm.machinfo->gpio_batlock);
	if (request_irq(irq, sharpsl_fatal_isr, IRQF_TRIGGER_FALLING, "Battery Cover", sharpsl_fatal_isr)) {
		dev_err(sharpsl_pm.dev, "Could not get irq %d.\n", irq);
	}

	if (sharpsl_pm.machinfo->gpio_fatal) {
		irq = gpio_to_irq(sharpsl_pm.machinfo->gpio_fatal);
		if (request_irq(irq, sharpsl_fatal_isr, IRQF_TRIGGER_FALLING, "Fatal Battery", sharpsl_fatal_isr)) {
			dev_err(sharpsl_pm.dev, "Could not get irq %d.\n", irq);
		}
	}

	if (sharpsl_pm.machinfo->batfull_irq) {
		/* Register interrupt handler. */
		irq = gpio_to_irq(sharpsl_pm.machinfo->gpio_batfull);
		if (request_irq(irq, sharpsl_chrg_full_isr, IRQF_TRIGGER_RISING, "CO", sharpsl_chrg_full_isr)) {
			dev_err(sharpsl_pm.dev, "Could not get irq %d.\n", irq);
		}
	}

	ret = device_create_file(&pdev->dev, &dev_attr_battery_percentage);
	ret |= device_create_file(&pdev->dev, &dev_attr_battery_voltage);
	if (ret != 0)
		dev_warn(&pdev->dev, "Failed to register attributes (%d)\n", ret);

	apm_get_power_status = sharpsl_apm_get_power_status;

#ifdef CONFIG_PM
	suspend_set_ops(&sharpsl_pm_ops);
#endif

	mod_timer(&sharpsl_pm.ac_timer, jiffies + msecs_to_jiffies(250));

	return 0;
}

static void sharpsl_pm_remove(struct platform_device *pdev)
{
	suspend_set_ops(NULL);

	device_remove_file(&pdev->dev, &dev_attr_battery_percentage);
	device_remove_file(&pdev->dev, &dev_attr_battery_voltage);

	led_trigger_unregister_simple(sharpsl_charge_led_trigger);

	free_irq(gpio_to_irq(sharpsl_pm.machinfo->gpio_acin), sharpsl_ac_isr);
	free_irq(gpio_to_irq(sharpsl_pm.machinfo->gpio_batlock), sharpsl_fatal_isr);

	if (sharpsl_pm.machinfo->gpio_fatal)
		free_irq(gpio_to_irq(sharpsl_pm.machinfo->gpio_fatal), sharpsl_fatal_isr);

	if (sharpsl_pm.machinfo->batfull_irq)
		free_irq(gpio_to_irq(sharpsl_pm.machinfo->gpio_batfull), sharpsl_chrg_full_isr);

	gpio_free(sharpsl_pm.machinfo->gpio_batlock);
	gpio_free(sharpsl_pm.machinfo->gpio_batfull);
	gpio_free(sharpsl_pm.machinfo->gpio_acin);

	if (sharpsl_pm.machinfo->exit)
		sharpsl_pm.machinfo->exit();

	timer_delete_sync(&sharpsl_pm.chrg_full_timer);
	timer_delete_sync(&sharpsl_pm.ac_timer);
}

static struct platform_driver sharpsl_pm_driver = {
	.probe		= sharpsl_pm_probe,
	.remove		= sharpsl_pm_remove,
	.suspend	= sharpsl_pm_suspend,
	.resume		= sharpsl_pm_resume,
	.driver		= {
		.name		= "sharpsl-pm",
	},
};

static int sharpsl_pm_init(void)
{
	return platform_driver_register(&sharpsl_pm_driver);
}

static void sharpsl_pm_exit(void)
{
	platform_driver_unregister(&sharpsl_pm_driver);
}

late_initcall(sharpsl_pm_init);
module_exit(sharpsl_pm_exit);