| Message ID | 20210223141122.9574-1-matthias.schiffer@ew.tq-group.com |
|---|---|
| State | Accepted |
| Commit | b67fdcb7099e9c640bad625c4dd6399debb3376a |
| Headers | show |
| Series | [1/3] power: supply: bq27xxx: fix sign of current_now for newer ICs | expand |
On Tuesday 23 February 2021 15:49:46 Andreas Kemnade wrote: > On Tue, 23 Feb 2021 15:11:20 +0100 > Matthias Schiffer <matthias.schiffer@ew.tq-group.com> wrote: > > > Commit cd060b4d0868 ("power: supply: bq27xxx: fix polarity of current_now") > > changed the sign of current_now for all bq27xxx variants, but on BQ28Z610 > > I'm now seeing negated values *with* that patch. > > > > The GTA04/Openmoko device that was used for testing uses a BQ27000 or > > BQ27010 IC, so I assume only the BQ27XXX_O_ZERO code path was incorrect. > > Revert the behaviour for newer ICs. > > > > Fixes: cd060b4d0868 "power: supply: bq27xxx: fix polarity of current_now" > > Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > > --- > > > > @Andreas Kemnade: It would be great to get a confirmation that the > > Openmoko battery indeed uses BQ27000/BQ27010 - I was having some trouble > > finding that information. > > > I can confirm that. > here is the corresponding schematic: > > http://people.openmoko.org/tony_tu/GTA02/hardware/GTA02/CT-GTA02.pdf > > Regards, > Andreas Nokia N900 has BQ27200 connected via i2c. CCing Maemo mailing list maemo-leste@lists.dyne.org
On Tue, 2021-02-23 at 15:11 +0100, Matthias Schiffer wrote: > 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 1mA and not 10mA. 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 1mA. At least, the new code shouldn't > be *less* correct than the old version for any device Ugh, of course this section should talk about mW and not mA. I'll wait if there is more feedback and then send a v2. > . > > 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 <matthias.schiffer@ew.tq-group.com> > --- > drivers/power/supply/bq27xxx_battery.c | 51 ++++++++++++++------------ > include/linux/power/bq27xxx_battery.h | 1 - > 2 files changed, 27 insertions(+), 25 deletions(-) > > 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); > diff --git a/include/linux/power/bq27xxx_battery.h b/include/linux/power/bq27xxx_battery.h > index 111a40d0d3d5..8d5f4f40fb41 100644 > --- a/include/linux/power/bq27xxx_battery.h > +++ b/include/linux/power/bq27xxx_battery.h > @@ -53,7 +53,6 @@ struct bq27xxx_reg_cache { > int capacity; > int energy; > int flags; > - int power_avg; > int health; > }; >
diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c index 4c4a7b1c64c5..cb6ebd2f905e 100644 --- a/drivers/power/supply/bq27xxx_battery.c +++ b/drivers/power/supply/bq27xxx_battery.c @@ -1827,7 +1827,7 @@ static int bq27xxx_battery_current(struct bq27xxx_device_info *di, val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS; } else { /* Other gauges return signed value */ - val->intval = -(int)((s16)curr) * 1000; + val->intval = (int)((s16)curr) * 1000; } return 0;
Commit cd060b4d0868 ("power: supply: bq27xxx: fix polarity of current_now") changed the sign of current_now for all bq27xxx variants, but on BQ28Z610 I'm now seeing negated values *with* that patch. The GTA04/Openmoko device that was used for testing uses a BQ27000 or BQ27010 IC, so I assume only the BQ27XXX_O_ZERO code path was incorrect. Revert the behaviour for newer ICs. Fixes: cd060b4d0868 "power: supply: bq27xxx: fix polarity of current_now" Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> --- @Andreas Kemnade: It would be great to get a confirmation that the Openmoko battery indeed uses BQ27000/BQ27010 - I was having some trouble finding that information. drivers/power/supply/bq27xxx_battery.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)