// SPDX-License-Identifier: GPL-2.0-only
/*
* Battery driver for One Laptop Per Child board.
*
* Copyright © 2006-2010 David Woodhouse <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/types.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/olpc-ec.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
struct olpc_battery_data {
struct power_supply *olpc_ac;
struct power_supply *olpc_bat;
char bat_serial[17];
bool new_proto;
bool little_endian;
};
/*********************************************************************
* 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 int olpc_bat_get_status(struct olpc_battery_data *data,
union power_supply_propval *val, uint8_t ec_byte)
{
if (data->new_proto) {
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;
}
static u16 ecword_to_cpu(struct olpc_battery_data *data, u16 ec_word)
{
if (data->little_endian)
return le16_to_cpu((__force __le16)ec_word);
else
return be16_to_cpu((__force __be16)ec_word);
}
/*********************************************************************
* Battery properties
*********************************************************************/
static int olpc_bat_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct olpc_battery_data *data = power_supply_get_drvdata(psy);
int ret = 0;
u16 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(data, 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 = ecword_to_cpu(data, 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 = ecword_to_cpu(data, 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 = ecword_to_cpu(data, ec_word) * 10 / 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)ecword_to_cpu(data, ec_word) * 10 / 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 = ecword_to_cpu(data, 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(data->bat_serial, "%016llx", (long long)be64_to_cpu(ser_buf));
val->strval = data->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 sysfs_emit(buf, "%d\n", ec_byte);
}
static struct device_attribute olpc_bat_error = {
.attr = {
.name = "error",
.mode = S_IRUGO,
},
.show = olpc_bat_error_read,
};
static struct attribute *olpc_bat_sysfs_attrs[] = {
&olpc_bat_error.attr,
NULL
};
static struct bin_attribute *olpc_bat_sysfs_bin_attrs[] = {
&olpc_bat_eeprom,
NULL
};
static const struct attribute_group olpc_bat_sysfs_group = {
.attrs = olpc_bat_sysfs_attrs,
.bin_attrs = olpc_bat_sysfs_bin_attrs,
};
static const struct attribute_group *olpc_bat_sysfs_groups[] = {
&olpc_bat_sysfs_group,
NULL
};
/*********************************************************************
* Initialisation
*********************************************************************/
static struct power_supply_desc olpc_bat_desc = {
.name = "olpc_battery",
.get_property = olpc_bat_get_property,
.use_for_apm = 1,
};
static int olpc_battery_suspend(struct platform_device *pdev,
pm_message_t state)
{
struct olpc_battery_data *data = platform_get_drvdata(pdev);
if (device_may_wakeup(&data->olpc_ac->dev))
olpc_ec_wakeup_set(EC_SCI_SRC_ACPWR);
else
olpc_ec_wakeup_clear(EC_SCI_SRC_ACPWR);
if (device_may_wakeup(&data->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)
{
struct power_supply_config bat_psy_cfg = {};
struct power_supply_config ac_psy_cfg = {};
struct olpc_battery_data *data;
struct device_node *np;
uint8_t status;
uint8_t ecver;
int ret;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
platform_set_drvdata(pdev, data);
/* See if the EC is already there and get the EC revision */
ret = olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0, &ecver, 1);
if (ret)
return ret;
np = of_find_compatible_node(NULL, NULL, "olpc,xo1.75-ec");
if (np) {
of_node_put(np);
/* XO 1.75 */
data->new_proto = true;
data->little_endian = true;
} else if (ecver > 0x44) {
/* XO 1 or 1.5 with a new EC firmware. */
data->new_proto = true;
} else if (ecver < 0x44) {
/*
* We've seen a number of EC protocol changes; this driver
* requires the latest EC protocol, supported by 0x44 and above.
*/
printk(KERN_NOTICE "OLPC EC version 0x%02x too old for "
"battery driver.\n", 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 */
ac_psy_cfg.of_node = pdev->dev.of_node;
ac_psy_cfg.drv_data = data;
data->olpc_ac = devm_power_supply_register(&pdev->dev, &olpc_ac_desc,
&ac_psy_cfg);
if (IS_ERR(data->olpc_ac))
return PTR_ERR(data->olpc_ac);
if (of_device_is_compatible(pdev->dev.of_node, "olpc,xo1.5-battery")) {
/* 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);
}
bat_psy_cfg.of_node = pdev->dev.of_node;
bat_psy_cfg.drv_data = data;
bat_psy_cfg.attr_grp = olpc_bat_sysfs_groups;
data->olpc_bat = devm_power_supply_register(&pdev->dev, &olpc_bat_desc,
&bat_psy_cfg);
if (IS_ERR(data->olpc_bat))
return PTR_ERR(data->olpc_bat);
if (olpc_ec_wakeup_available()) {
device_set_wakeup_capable(&data->olpc_ac->dev, true);
device_set_wakeup_capable(&data->olpc_bat->dev, true);
}
return 0;
}
static const struct of_device_id olpc_battery_ids[] = {
{ .compatible = "olpc,xo1-battery" },
{ .compatible = "olpc,xo1.5-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,
.suspend = olpc_battery_suspend,
};
module_platform_driver(olpc_battery_driver);
MODULE_AUTHOR("David Woodhouse <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
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