diff options
| author | Andres Salomon <dilinger@queued.net> | 2008-05-15 01:20:38 +0200 |
|---|---|---|
| committer | Anton Vorontsov <cbouatmailru@gmail.com> | 2008-05-18 23:44:36 +0200 |
| commit | 75d8807962fc7529b4946e9ec92cae197be5a967 (patch) | |
| tree | 9e5370ea7e1c727a18c4cb47c8403779456cbebe /drivers/power | |
| parent | power_supply: add CHARGE_COUNTER property and olpc_battery support for it (diff) | |
| download | linux-75d8807962fc7529b4946e9ec92cae197be5a967.tar.xz linux-75d8807962fc7529b4946e9ec92cae197be5a967.zip | |
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 <dilinger@debian.org>
Cc: "Richard A. Smith" <richard@laptop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Diffstat (limited to 'drivers/power')
| -rw-r--r-- | drivers/power/olpc_battery.c | 4 |
1 files 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); |