From c4d57c22ac65bd503716062a06fad55a01569cac Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Wed, 3 Mar 2021 10:54:19 +0100 Subject: power: supply: bq27xxx: fix power_avg for newer ICs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On all newer bq27xxx ICs, the AveragePower register contains a signed value; in addition to handling the raw value as unsigned, the driver code also didn't convert it to µW as expected. At least for the BQ28Z610, the reference manual incorrectly states that the value is in units of 1mW and not 10mW. I have no way of knowing whether the manuals of other supported ICs contain the same error, or if there are models that actually use 1mW. At least, the new code shouldn't be *less* correct than the old version for any device. power_avg is removed from the cache structure, se we don't have to extend it to store both a signed value and an error code. Always getting an up-to-date value may be desirable anyways, as it avoids inconsistent current and power readings when switching between charging and discharging. Signed-off-by: Matthias Schiffer Signed-off-by: Sebastian Reichel --- drivers/power/supply/bq27xxx_battery.c | 51 ++++++++++++++++++---------------- 1 file changed, 27 insertions(+), 24 deletions(-) (limited to 'drivers/power/supply/bq27xxx_battery.c') diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c index cb6ebd2f905e..20e1dc8a87cf 100644 --- a/drivers/power/supply/bq27xxx_battery.c +++ b/drivers/power/supply/bq27xxx_battery.c @@ -1661,27 +1661,6 @@ static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg) return tval * 60; } -/* - * Read an average power register. - * Return < 0 if something fails. - */ -static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di) -{ - int tval; - - tval = bq27xxx_read(di, BQ27XXX_REG_AP, false); - if (tval < 0) { - dev_err(di->dev, "error reading average power register %02x: %d\n", - BQ27XXX_REG_AP, tval); - return tval; - } - - if (di->opts & BQ27XXX_O_ZERO) - return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS; - else - return tval; -} - /* * Returns true if a battery over temperature condition is detected */ @@ -1769,8 +1748,6 @@ void bq27xxx_battery_update(struct bq27xxx_device_info *di) } if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR) cache.cycle_count = bq27xxx_battery_read_cyct(di); - if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR) - cache.power_avg = bq27xxx_battery_read_pwr_avg(di); /* We only have to read charge design full once */ if (di->charge_design_full <= 0) @@ -1833,6 +1810,32 @@ static int bq27xxx_battery_current(struct bq27xxx_device_info *di, return 0; } +/* + * Get the average power in µW + * Return < 0 if something fails. + */ +static int bq27xxx_battery_pwr_avg(struct bq27xxx_device_info *di, + union power_supply_propval *val) +{ + int power; + + power = bq27xxx_read(di, BQ27XXX_REG_AP, false); + if (power < 0) { + dev_err(di->dev, + "error reading average power register %02x: %d\n", + BQ27XXX_REG_AP, power); + return power; + } + + if (di->opts & BQ27XXX_O_ZERO) + val->intval = (power * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS; + else + /* Other gauges return a signed value in units of 10mW */ + val->intval = (int)((s16)power) * 10000; + + return 0; +} + static int bq27xxx_battery_status(struct bq27xxx_device_info *di, union power_supply_propval *val) { @@ -2020,7 +2023,7 @@ static int bq27xxx_battery_get_property(struct power_supply *psy, ret = bq27xxx_simple_value(di->cache.energy, val); break; case POWER_SUPPLY_PROP_POWER_AVG: - ret = bq27xxx_simple_value(di->cache.power_avg, val); + ret = bq27xxx_battery_pwr_avg(di, val); break; case POWER_SUPPLY_PROP_HEALTH: ret = bq27xxx_simple_value(di->cache.health, val); -- cgit v1.2.3