1 files changed, 692 insertions, 0 deletions

diff --git a/drivers/power/supply/olpc_battery.c b/drivers/power/supply/olpc_battery.c
new file mode 100644
index 0000000..9e29b13
--- /dev/null
+++ b/drivers/power/supply/olpc_battery.c
@@ -0,0 +1,692 @@
+/*
+ * Battery driver for One Laptop Per Child board.
+ *
+ *	Copyright © 2006-2010  David Woodhouse <dwmw2@infradead.org>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/jiffies.h>
+#include <linux/sched.h>
+#include <linux/olpc-ec.h>
+#include <asm/olpc.h>
+
+
+#define EC_BAT_VOLTAGE	0x10	/* uint16_t,	*9.76/32,    mV   */
+#define EC_BAT_CURRENT	0x11	/* int16_t,	*15.625/120, mA   */
+#define EC_BAT_ACR	0x12	/* int16_t,	*6250/15,    µAh  */
+#define EC_BAT_TEMP	0x13	/* uint16_t,	*100/256,   °C  */
+#define EC_AMB_TEMP	0x14	/* uint16_t,	*100/256,   °C  */
+#define EC_BAT_STATUS	0x15	/* uint8_t,	bitmask */
+#define EC_BAT_SOC	0x16	/* uint8_t,	percentage */
+#define EC_BAT_SERIAL	0x17	/* uint8_t[6] */
+#define EC_BAT_EEPROM	0x18	/* uint8_t adr as input, uint8_t output */
+#define EC_BAT_ERRCODE	0x1f	/* uint8_t,	bitmask */
+
+#define BAT_STAT_PRESENT	0x01
+#define BAT_STAT_FULL		0x02
+#define BAT_STAT_LOW		0x04
+#define BAT_STAT_DESTROY	0x08
+#define BAT_STAT_AC		0x10
+#define BAT_STAT_CHARGING	0x20
+#define BAT_STAT_DISCHARGING	0x40
+#define BAT_STAT_TRICKLE	0x80
+
+#define BAT_ERR_INFOFAIL	0x02
+#define BAT_ERR_OVERVOLTAGE	0x04
+#define BAT_ERR_OVERTEMP	0x05
+#define BAT_ERR_GAUGESTOP	0x06
+#define BAT_ERR_OUT_OF_CONTROL	0x07
+#define BAT_ERR_ID_FAIL		0x09
+#define BAT_ERR_ACR_FAIL	0x10
+
+#define BAT_ADDR_MFR_TYPE	0x5F
+
+/*********************************************************************
+ *		Power
+ *********************************************************************/
+
+static int olpc_ac_get_prop(struct power_supply *psy,
+			    enum power_supply_property psp,
+			    union power_supply_propval *val)
+{
+	int ret = 0;
+	uint8_t status;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_ONLINE:
+		ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
+		if (ret)
+			return ret;
+
+		val->intval = !!(status & BAT_STAT_AC);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static enum power_supply_property olpc_ac_props[] = {
+	POWER_SUPPLY_PROP_ONLINE,
+};
+
+static const struct power_supply_desc olpc_ac_desc = {
+	.name = "olpc-ac",
+	.type = POWER_SUPPLY_TYPE_MAINS,
+	.properties = olpc_ac_props,
+	.num_properties = ARRAY_SIZE(olpc_ac_props),
+	.get_property = olpc_ac_get_prop,
+};
+
+static struct power_supply *olpc_ac;
+
+static char bat_serial[17]; /* Ick */
+
+static int olpc_bat_get_status(union power_supply_propval *val, uint8_t ec_byte)
+{
+	if (olpc_platform_info.ecver > 0x44) {
+		if (ec_byte & (BAT_STAT_CHARGING | BAT_STAT_TRICKLE))
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+		else if (ec_byte & BAT_STAT_DISCHARGING)
+			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+		else if (ec_byte & BAT_STAT_FULL)
+			val->intval = POWER_SUPPLY_STATUS_FULL;
+		else /* er,... */
+			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+	} else {
+		/* Older EC didn't report charge/discharge bits */
+		if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
+			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+		else if (ec_byte & BAT_STAT_FULL)
+			val->intval = POWER_SUPPLY_STATUS_FULL;
+		else /* Not _necessarily_ true but EC doesn't tell all yet */
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+	}
+
+	return 0;
+}
+
+static int olpc_bat_get_health(union power_supply_propval *val)
+{
+	uint8_t ec_byte;
+	int ret;
+
+	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	switch (ec_byte) {
+	case 0:
+		val->intval = POWER_SUPPLY_HEALTH_GOOD;
+		break;
+
+	case BAT_ERR_OVERTEMP:
+		val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
+		break;
+
+	case BAT_ERR_OVERVOLTAGE:
+		val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+		break;
+
+	case BAT_ERR_INFOFAIL:
+	case BAT_ERR_OUT_OF_CONTROL:
+	case BAT_ERR_ID_FAIL:
+	case BAT_ERR_ACR_FAIL:
+		val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
+		break;
+
+	default:
+		/* Eep. We don't know this failure code */
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static int olpc_bat_get_mfr(union power_supply_propval *val)
+{
+	uint8_t ec_byte;
+	int ret;
+
+	ec_byte = BAT_ADDR_MFR_TYPE;
+	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	switch (ec_byte >> 4) {
+	case 1:
+		val->strval = "Gold Peak";
+		break;
+	case 2:
+		val->strval = "BYD";
+		break;
+	default:
+		val->strval = "Unknown";
+		break;
+	}
+
+	return ret;
+}
+
+static int olpc_bat_get_tech(union power_supply_propval *val)
+{
+	uint8_t ec_byte;
+	int ret;
+
+	ec_byte = BAT_ADDR_MFR_TYPE;
+	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	switch (ec_byte & 0xf) {
+	case 1:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
+		break;
+	case 2:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_LiFe;
+		break;
+	default:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
+		break;
+	}
+
+	return ret;
+}
+
+static int olpc_bat_get_charge_full_design(union power_supply_propval *val)
+{
+	uint8_t ec_byte;
+	union power_supply_propval tech;
+	int ret, mfr;
+
+	ret = olpc_bat_get_tech(&tech);
+	if (ret)
+		return ret;
+
+	ec_byte = BAT_ADDR_MFR_TYPE;
+	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	mfr = ec_byte >> 4;
+
+	switch (tech.intval) {
+	case POWER_SUPPLY_TECHNOLOGY_NiMH:
+		switch (mfr) {
+		case 1: /* Gold Peak */
+			val->intval = 3000000*.8;
+			break;
+		default:
+			return -EIO;
+		}
+		break;
+
+	case POWER_SUPPLY_TECHNOLOGY_LiFe:
+		switch (mfr) {
+		case 1: /* Gold Peak, fall through */
+		case 2: /* BYD */
+			val->intval = 2800000;
+			break;
+		default:
+			return -EIO;
+		}
+		break;
+
+	default:
+		return -EIO;
+	}
+
+	return ret;
+}
+
+static int olpc_bat_get_charge_now(union power_supply_propval *val)
+{
+	uint8_t soc;
+	union power_supply_propval full;
+	int ret;
+
+	ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &soc, 1);
+	if (ret)
+		return ret;
+
+	ret = olpc_bat_get_charge_full_design(&full);
+	if (ret)
+		return ret;
+
+	val->intval = soc * (full.intval / 100);
+	return 0;
+}
+
+static int olpc_bat_get_voltage_max_design(union power_supply_propval *val)
+{
+	uint8_t ec_byte;
+	union power_supply_propval tech;
+	int mfr;
+	int ret;
+
+	ret = olpc_bat_get_tech(&tech);
+	if (ret)
+		return ret;
+
+	ec_byte = BAT_ADDR_MFR_TYPE;
+	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	mfr = ec_byte >> 4;
+
+	switch (tech.intval) {
+	case POWER_SUPPLY_TECHNOLOGY_NiMH:
+		switch (mfr) {
+		case 1: /* Gold Peak */
+			val->intval = 6000000;
+			break;
+		default:
+			return -EIO;
+		}
+		break;
+
+	case POWER_SUPPLY_TECHNOLOGY_LiFe:
+		switch (mfr) {
+		case 1: /* Gold Peak */
+			val->intval = 6400000;
+			break;
+		case 2: /* BYD */
+			val->intval = 6500000;
+			break;
+		default:
+			return -EIO;
+		}
+		break;
+
+	default:
+		return -EIO;
+	}
+
+	return ret;
+}
+
+/*********************************************************************
+ *		Battery properties
+ *********************************************************************/
+static int olpc_bat_get_property(struct power_supply *psy,
+				 enum power_supply_property psp,
+				 union power_supply_propval *val)
+{
+	int ret = 0;
+	__be16 ec_word;
+	uint8_t ec_byte;
+	__be64 ser_buf;
+
+	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
+	if (ret)
+		return ret;
+
+	/* Theoretically there's a race here -- the battery could be
+	   removed immediately after we check whether it's present, and
+	   then we query for some other property of the now-absent battery.
+	   It doesn't matter though -- the EC will return the last-known
+	   information, and it's as if we just ran that _little_ bit faster
+	   and managed to read it out before the battery went away. */
+	if (!(ec_byte & (BAT_STAT_PRESENT | BAT_STAT_TRICKLE)) &&
+			psp != POWER_SUPPLY_PROP_PRESENT)
+		return -ENODEV;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		ret = olpc_bat_get_status(val, ec_byte);
+		if (ret)
+			return ret;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_TYPE:
+		if (ec_byte & BAT_STAT_TRICKLE)
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
+		else if (ec_byte & BAT_STAT_CHARGING)
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
+		else
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = !!(ec_byte & (BAT_STAT_PRESENT |
+					    BAT_STAT_TRICKLE));
+		break;
+
+	case POWER_SUPPLY_PROP_HEALTH:
+		if (ec_byte & BAT_STAT_DESTROY)
+			val->intval = POWER_SUPPLY_HEALTH_DEAD;
+		else {
+			ret = olpc_bat_get_health(val);
+			if (ret)
+				return ret;
+		}
+		break;
+
+	case POWER_SUPPLY_PROP_MANUFACTURER:
+		ret = olpc_bat_get_mfr(val);
+		if (ret)
+			return ret;
+		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		ret = olpc_bat_get_tech(val);
+		if (ret)
+			return ret;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
+		if (ret)
+			return ret;
+
+		val->intval = (s16)be16_to_cpu(ec_word) * 9760L / 32;
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_AVG:
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
+		if (ret)
+			return ret;
+
+		val->intval = (s16)be16_to_cpu(ec_word) * 15625L / 120;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
+		if (ret)
+			return ret;
+		val->intval = ec_byte;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+		if (ec_byte & BAT_STAT_FULL)
+			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+		else if (ec_byte & BAT_STAT_LOW)
+			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+		else
+			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+		ret = olpc_bat_get_charge_full_design(val);
+		if (ret)
+			return ret;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_NOW:
+		ret = olpc_bat_get_charge_now(val);
+		if (ret)
+			return ret;
+		break;
+	case POWER_SUPPLY_PROP_TEMP:
+		ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
+		if (ret)
+			return ret;
+
+		val->intval = (s16)be16_to_cpu(ec_word) * 100 / 256;
+		break;
+	case POWER_SUPPLY_PROP_TEMP_AMBIENT:
+		ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
+		if (ret)
+			return ret;
+
+		val->intval = (int)be16_to_cpu(ec_word) * 100 / 256;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
+		ret = olpc_ec_cmd(EC_BAT_ACR, NULL, 0, (void *)&ec_word, 2);
+		if (ret)
+			return ret;
+
+		val->intval = (s16)be16_to_cpu(ec_word) * 6250 / 15;
+		break;
+	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+		ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8);
+		if (ret)
+			return ret;
+
+		sprintf(bat_serial, "%016llx", (long long)be64_to_cpu(ser_buf));
+		val->strval = bat_serial;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+		ret = olpc_bat_get_voltage_max_design(val);
+		if (ret)
+			return ret;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static enum power_supply_property olpc_xo1_bat_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_CHARGE_TYPE,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_VOLTAGE_AVG,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_AVG,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TEMP_AMBIENT,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+	POWER_SUPPLY_PROP_SERIAL_NUMBER,
+	POWER_SUPPLY_PROP_CHARGE_COUNTER,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+};
+
+/* XO-1.5 does not have ambient temperature property */
+static enum power_supply_property olpc_xo15_bat_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_CHARGE_TYPE,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_VOLTAGE_AVG,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_AVG,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+	POWER_SUPPLY_PROP_SERIAL_NUMBER,
+	POWER_SUPPLY_PROP_CHARGE_COUNTER,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+};
+
+/* EEPROM reading goes completely around the power_supply API, sadly */
+
+#define EEPROM_START	0x20
+#define EEPROM_END	0x80
+#define EEPROM_SIZE	(EEPROM_END - EEPROM_START)
+
+static ssize_t olpc_bat_eeprom_read(struct file *filp, struct kobject *kobj,
+		struct bin_attribute *attr, char *buf, loff_t off, size_t count)
+{
+	uint8_t ec_byte;
+	int ret;
+	int i;
+
+	for (i = 0; i < count; i++) {
+		ec_byte = EEPROM_START + off + i;
+		ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &buf[i], 1);
+		if (ret) {
+			pr_err("olpc-battery: "
+			       "EC_BAT_EEPROM cmd @ 0x%x failed - %d!\n",
+			       ec_byte, ret);
+			return -EIO;
+		}
+	}
+
+	return count;
+}
+
+static struct bin_attribute olpc_bat_eeprom = {
+	.attr = {
+		.name = "eeprom",
+		.mode = S_IRUGO,
+	},
+	.size = EEPROM_SIZE,
+	.read = olpc_bat_eeprom_read,
+};
+
+/* Allow userspace to see the specific error value pulled from the EC */
+
+static ssize_t olpc_bat_error_read(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	uint8_t ec_byte;
+	ssize_t ret;
+
+	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", ec_byte);
+}
+
+static struct device_attribute olpc_bat_error = {
+	.attr = {
+		.name = "error",
+		.mode = S_IRUGO,
+	},
+	.show = olpc_bat_error_read,
+};
+
+/*********************************************************************
+ *		Initialisation
+ *********************************************************************/
+
+static struct power_supply_desc olpc_bat_desc = {
+	.name = "olpc-battery",
+	.get_property = olpc_bat_get_property,
+	.use_for_apm = 1,
+};
+
+static struct power_supply *olpc_bat;
+
+static int olpc_battery_suspend(struct platform_device *pdev,
+				pm_message_t state)
+{
+	if (device_may_wakeup(&olpc_ac->dev))
+		olpc_ec_wakeup_set(EC_SCI_SRC_ACPWR);
+	else
+		olpc_ec_wakeup_clear(EC_SCI_SRC_ACPWR);
+
+	if (device_may_wakeup(&olpc_bat->dev))
+		olpc_ec_wakeup_set(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
+				   | EC_SCI_SRC_BATERR);
+	else
+		olpc_ec_wakeup_clear(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
+				     | EC_SCI_SRC_BATERR);
+
+	return 0;
+}
+
+static int olpc_battery_probe(struct platform_device *pdev)
+{
+	int ret;
+	uint8_t status;
+
+	/*
+	 * We've seen a number of EC protocol changes; this driver requires
+	 * the latest EC protocol, supported by 0x44 and above.
+	 */
+	if (olpc_platform_info.ecver < 0x44) {
+		printk(KERN_NOTICE "OLPC EC version 0x%02x too old for "
+			"battery driver.\n", olpc_platform_info.ecver);
+		return -ENXIO;
+	}
+
+	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
+	if (ret)
+		return ret;
+
+	/* Ignore the status. It doesn't actually matter */
+
+	olpc_ac = power_supply_register(&pdev->dev, &olpc_ac_desc, NULL);
+	if (IS_ERR(olpc_ac))
+		return PTR_ERR(olpc_ac);
+
+	if (olpc_board_at_least(olpc_board_pre(0xd0))) { /* XO-1.5 */
+		olpc_bat_desc.properties = olpc_xo15_bat_props;
+		olpc_bat_desc.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
+	} else { /* XO-1 */
+		olpc_bat_desc.properties = olpc_xo1_bat_props;
+		olpc_bat_desc.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
+	}
+
+	olpc_bat = power_supply_register(&pdev->dev, &olpc_bat_desc, NULL);
+	if (IS_ERR(olpc_bat)) {
+		ret = PTR_ERR(olpc_bat);
+		goto battery_failed;
+	}
+
+	ret = device_create_bin_file(&olpc_bat->dev, &olpc_bat_eeprom);
+	if (ret)
+		goto eeprom_failed;
+
+	ret = device_create_file(&olpc_bat->dev, &olpc_bat_error);
+	if (ret)
+		goto error_failed;
+
+	if (olpc_ec_wakeup_available()) {
+		device_set_wakeup_capable(&olpc_ac->dev, true);
+		device_set_wakeup_capable(&olpc_bat->dev, true);
+	}
+
+	return 0;
+
+error_failed:
+	device_remove_bin_file(&olpc_bat->dev, &olpc_bat_eeprom);
+eeprom_failed:
+	power_supply_unregister(olpc_bat);
+battery_failed:
+	power_supply_unregister(olpc_ac);
+	return ret;
+}
+
+static int olpc_battery_remove(struct platform_device *pdev)
+{
+	device_remove_file(&olpc_bat->dev, &olpc_bat_error);
+	device_remove_bin_file(&olpc_bat->dev, &olpc_bat_eeprom);
+	power_supply_unregister(olpc_bat);
+	power_supply_unregister(olpc_ac);
+	return 0;
+}
+
+static const struct of_device_id olpc_battery_ids[] = {
+	{ .compatible = "olpc,xo1-battery" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, olpc_battery_ids);
+
+static struct platform_driver olpc_battery_driver = {
+	.driver = {
+		.name = "olpc-battery",
+		.of_match_table = olpc_battery_ids,
+	},
+	.probe = olpc_battery_probe,
+	.remove = olpc_battery_remove,
+	.suspend = olpc_battery_suspend,
+};
+
+module_platform_driver(olpc_battery_driver);
+
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");