linux/drivers/power/olpc_battery.c
Andres Salomon 8e552c36d9 power_supply: add CHARGE_COUNTER property and olpc_battery support for it
This adds PROP_CHARGE_COUNTER to the power supply class (documenting it
as well).  The OLPC battery driver uses this for spitting out its ACR
values (in uAh).  We have some rounding errors (the data sheet claims
416.7, the math actually works out to 416.666667, so we're forced to
choose between overflows or precision loss.  I chose precision loss,
and stuck w/ data sheet values), but I don't think anyone will care
that much.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2008-05-13 12:27:11 +04:00

462 lines
11 KiB
C

/*
* Battery driver for One Laptop Per Child board.
*
* Copyright © 2006 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/module.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/jiffies.h>
#include <linux/sched.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, *416.7, 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_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 struct power_supply olpc_ac = {
.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 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)
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;
}
/*********************************************************************
* 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;
int16_t ec_word;
uint8_t ec_byte;
uint64_t 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) && 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_PRESENT:
val->intval = !!(ec_byte & BAT_STAT_PRESENT);
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:
ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
if (ret)
return ret;
ec_word = be16_to_cpu(ec_word);
val->intval = ec_word * 9760L / 32;
break;
case POWER_SUPPLY_PROP_CURRENT_AVG:
ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
if (ret)
return ret;
ec_word = be16_to_cpu(ec_word);
val->intval = 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_TEMP:
ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
if (ret)
return ret;
ec_word = be16_to_cpu(ec_word);
val->intval = 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;
ec_word = be16_to_cpu(ec_word);
val->intval = 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;
ec_word = be16_to_cpu(ec_word);
val->intval = ec_word * 4167 / 10;
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;
default:
ret = -EINVAL;
break;
}
return ret;
}
static enum power_supply_property olpc_bat_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_VOLTAGE_AVG,
POWER_SUPPLY_PROP_CURRENT_AVG,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_TEMP_AMBIENT,
POWER_SUPPLY_PROP_MANUFACTURER,
POWER_SUPPLY_PROP_SERIAL_NUMBER,
POWER_SUPPLY_PROP_CHARGE_COUNTER,
};
/* 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 kobject *kobj,
struct bin_attribute *attr, char *buf, loff_t off, size_t count)
{
uint8_t ec_byte;
int ret, end;
if (off >= EEPROM_SIZE)
return 0;
if (off + count > EEPROM_SIZE)
count = EEPROM_SIZE - off;
end = EEPROM_START + off + count;
for (ec_byte = EEPROM_START + off; ec_byte < end; ec_byte++) {
ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1,
&buf[ec_byte - EEPROM_START], 1);
if (ret) {
printk(KERN_ERR "olpc-battery: EC command "
"EC_BAT_EEPROM @ 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,
.owner = THIS_MODULE,
},
.size = 0,
.read = olpc_bat_eeprom_read,
};
/*********************************************************************
* Initialisation
*********************************************************************/
static struct platform_device *bat_pdev;
static struct power_supply olpc_bat = {
.properties = olpc_bat_props,
.num_properties = ARRAY_SIZE(olpc_bat_props),
.get_property = olpc_bat_get_property,
.use_for_apm = 1,
};
void olpc_battery_trigger_uevent(unsigned long cause)
{
if (cause & EC_SCI_SRC_ACPWR)
kobject_uevent(&olpc_ac.dev->kobj, KOBJ_CHANGE);
if (cause & (EC_SCI_SRC_BATERR|EC_SCI_SRC_BATSOC|EC_SCI_SRC_BATTERY))
kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
}
static int __init olpc_bat_init(void)
{
int ret = 0;
uint8_t status;
if (!olpc_platform_info.ecver)
return -ENXIO;
/*
* 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 */
bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
if (IS_ERR(bat_pdev))
return PTR_ERR(bat_pdev);
ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
if (ret)
goto ac_failed;
olpc_bat.name = bat_pdev->name;
ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
if (ret)
goto battery_failed;
ret = device_create_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
if (ret)
goto eeprom_failed;
goto success;
eeprom_failed:
power_supply_unregister(&olpc_bat);
battery_failed:
power_supply_unregister(&olpc_ac);
ac_failed:
platform_device_unregister(bat_pdev);
success:
return ret;
}
static void __exit olpc_bat_exit(void)
{
device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
power_supply_unregister(&olpc_bat);
power_supply_unregister(&olpc_ac);
platform_device_unregister(bat_pdev);
}
module_init(olpc_bat_init);
module_exit(olpc_bat_exit);
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");