From 75d8807962fc7529b4946e9ec92cae197be5a967 Mon Sep 17 00:00:00 2001 From: Andres Salomon Date: Wed, 14 May 2008 16:20:38 -0700 Subject: power_supply: fix up CHARGE_COUNTER output to be more precise As Richard Smith pointed out, ACR * 6250 / 15 provides for less precision loss than ACR * 4167 / 10, _and_ it doesn't overflow. Switch to using that equation for CHARGE_COUNTER. Signed-off-by: Andres Salomon Cc: "Richard A. Smith" Signed-off-by: Andrew Morton Signed-off-by: Anton Vorontsov --- drivers/power/olpc_battery.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c index 9dd1589733c2..32570af3c5c9 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 /* int16_t, *416.7, µAh */ +#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 */ @@ -295,7 +295,7 @@ static int olpc_bat_get_property(struct power_supply *psy, return ret; ec_word = be16_to_cpu(ec_word); - val->intval = ec_word * 4167 / 10; + val->intval = ec_word * 6250 / 15; break; case POWER_SUPPLY_PROP_SERIAL_NUMBER: ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8); -- cgit v1.2.1