diff options
Diffstat (limited to 'drivers/power/olpc_battery.c')
| -rw-r--r-- | drivers/power/olpc_battery.c | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c new file mode 100644 index 00000000000..c998e68d060 --- /dev/null +++ b/drivers/power/olpc_battery.c @@ -0,0 +1,351 @@ +/* + * 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 +#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, +}; + +/********************************************************************* + * 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; + + 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: + 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; + 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_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 */ + return -EIO; + } + } + break; + + case POWER_SUPPLY_PROP_MANUFACTURER: + 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; + } + break; + case POWER_SUPPLY_PROP_TECHNOLOGY: + 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; + } + 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_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_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; + 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_CAPACITY_LEVEL, + POWER_SUPPLY_PROP_TEMP, + POWER_SUPPLY_PROP_TEMP_AMBIENT, + POWER_SUPPLY_PROP_MANUFACTURER, +}; + +/********************************************************************* + * 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; + if (olpc_platform_info.ecver < 0x43) { + 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; + + olpc_register_battery_callback(&olpc_battery_trigger_uevent); + goto success; + +battery_failed: + power_supply_unregister(&olpc_ac); +ac_failed: + platform_device_unregister(bat_pdev); +success: + return ret; +} + +static void __exit olpc_bat_exit(void) +{ + olpc_deregister_battery_callback(); + 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"); |