From 8e552c36d90c03d2cabf5373788998966751b609 Mon Sep 17 00:00:00 2001 From: Andres Salomon Date: Mon, 12 May 2008 21:46:29 -0400 Subject: [PATCH] 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 Signed-off-by: Anton Vorontsov --- Documentation/power/power_supply_class.txt | 4 ++++ drivers/power/olpc_battery.c | 11 ++++++++++- drivers/power/power_supply_sysfs.c | 1 + include/linux/power_supply.h | 1 + 4 files changed, 16 insertions(+), 1 deletion(-) diff --git a/Documentation/power/power_supply_class.txt b/Documentation/power/power_supply_class.txt index a8686e5a6857..c6cd4956047c 100644 --- a/Documentation/power/power_supply_class.txt +++ b/Documentation/power/power_supply_class.txt @@ -101,6 +101,10 @@ of charge when battery became full/empty". It also could mean "value of charge when battery considered full/empty at given conditions (temperature, age)". I.e. these attributes represents real thresholds, not design values. +CHARGE_COUNTER - the current charge counter (in µAh). This could easily +be negative; there is no empty or full value. It is only useful for +relative, time-based measurements. + ENERGY_FULL, ENERGY_EMPTY - same as above but for energy. CAPACITY - capacity in percents. diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c index c8b596a7fc94..9dd1589733c2 100644 --- a/drivers/power/olpc_battery.c +++ b/drivers/power/olpc_battery.c @@ -19,7 +19,7 @@ #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_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 */ @@ -289,6 +289,14 @@ static int olpc_bat_get_property(struct power_supply *psy, 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) @@ -317,6 +325,7 @@ static enum power_supply_property olpc_bat_props[] = { 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 */ diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c index c444d6b10c58..82e1246eeb0a 100644 --- a/drivers/power/power_supply_sysfs.c +++ b/drivers/power/power_supply_sysfs.c @@ -99,6 +99,7 @@ static struct device_attribute power_supply_attrs[] = { POWER_SUPPLY_ATTR(charge_empty), POWER_SUPPLY_ATTR(charge_now), POWER_SUPPLY_ATTR(charge_avg), + POWER_SUPPLY_ATTR(charge_counter), POWER_SUPPLY_ATTR(energy_full_design), POWER_SUPPLY_ATTR(energy_empty_design), POWER_SUPPLY_ATTR(energy_full), diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index 68ed19ccf1f7..ea96ead1d39d 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -78,6 +78,7 @@ enum power_supply_property { POWER_SUPPLY_PROP_CHARGE_EMPTY, POWER_SUPPLY_PROP_CHARGE_NOW, POWER_SUPPLY_PROP_CHARGE_AVG, + POWER_SUPPLY_PROP_CHARGE_COUNTER, POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN, POWER_SUPPLY_PROP_ENERGY_FULL,