/* * 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_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_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");