/* * 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/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 <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 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 | 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; } /********************************************************************* * 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: ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2); if (ret) return ret; val->intval = (int)be16_to_cpu(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; val->intval = (int)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_TEMP: ret = olpc_ec_cmd(EC_BAT_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_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 = (int)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; default: ret = -EINVAL; break; } return ret; } static enum power_supply_property olpc_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_CURRENT_AVG, POWER_SUPPLY_PROP_CAPACITY, POWER_SUPPLY_PROP_CAPACITY_LEVEL, 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; int i; if (off >= EEPROM_SIZE) return 0; if (off + count > EEPROM_SIZE) count = EEPROM_SIZE - off; 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, .owner = THIS_MODULE, }, .size = 0, .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 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; ret = device_create_file(olpc_bat.dev, &olpc_bat_error); if (ret) goto error_failed; goto success; 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); ac_failed: platform_device_unregister(bat_pdev); success: return ret; } static void __exit olpc_bat_exit(void) { 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); 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");