// SPDX-License-Identifier: GPL-2.0-only /* * Battery driver for One Laptop Per Child board. * * Copyright © 2006-2010 David Woodhouse <dwmw2@infradead.org> */ #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 sprintf(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; 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; if (of_find_compatible_node(NULL, NULL, "olpc,xo1.75-ec")) { /* 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 <dwmw2@infradead.org>"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");