On Tue, Jun 13, 2017 at 10:53 AM, Shawn Nematbakhsh <[email protected]> wrote: > A subset of smart battery commands return charge or energy depending on > the CAPACITY_MODE bit setting of BatteryMode(). In order to > unambiguously read a charge or energy value, it is necessary to ensure > that CAPACITY_MODE is set as desired, and not changed for the duration > of the attribute read. > > Signed-off-by: Shawn Nematbakhsh <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]> > --- > drivers/power/supply/sbs-battery.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/power/supply/sbs-battery.c > b/drivers/power/supply/sbs-battery.c > index e3a114e60f1a..d7e68fd97099 100644 > --- a/drivers/power/supply/sbs-battery.c > +++ b/drivers/power/supply/sbs-battery.c > @@ -171,6 +171,7 @@ struct sbs_info { > u32 i2c_retry_count; > u32 poll_retry_count; > struct delayed_work work; > + struct mutex mode_lock; > }; > > static char model_name[I2C_SMBUS_BLOCK_MAX + 1]; > @@ -623,7 +624,13 @@ static int sbs_get_property(struct power_supply *psy, > if (ret < 0) > break; > > + /* sbs_get_battery_capacity() will change the battery mode > + * temporarily to read the requested attribute. Ensure we stay > + * in the desired mode for the duration of the attribute read. > + */ > + mutex_lock(&chip->mode_lock); > ret = sbs_get_battery_capacity(client, ret, psp, val); > + mutex_unlock(&chip->mode_lock); > break; > > case POWER_SUPPLY_PROP_SERIAL_NUMBER: > @@ -808,6 +815,7 @@ static int sbs_probe(struct i2c_client *client, > psy_cfg.of_node = client->dev.of_node; > psy_cfg.drv_data = chip; > chip->last_state = POWER_SUPPLY_STATUS_UNKNOWN; > + mutex_init(&chip->mode_lock); > > /* use pdata if available, fall back to DT properties, > * or hardcoded defaults if not > -- > 2.13.1.508.gb3defc5cc-goog >
