A new device property called "ti,pg-gpio-disable" is introduced to allow disabling the GPIO-based Power Good implementation, and replacing it with a SW-only alternative. This is helpful for devices which don't have a dedicated PG pin such as bq25250.
Signed-off-by: Andreas Dannenberg <[email protected]> --- drivers/power/bq24257_charger.c | 46 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 41 insertions(+), 5 deletions(-) diff --git a/drivers/power/bq24257_charger.c b/drivers/power/bq24257_charger.c index 229fbce..2d396c3 100644 --- a/drivers/power/bq24257_charger.c +++ b/drivers/power/bq24257_charger.c @@ -70,6 +70,7 @@ struct bq24257_init_data { u8 iterm; /* termination current */ u8 in_ilimit; /* input current limit */ bool in_ilimit_autoset_disable; /* auto-detect of input current limit */ + bool pg_gpio_disable; /* use of a dedicated pin for Power Good */ }; struct bq24257_state { @@ -99,6 +100,7 @@ struct bq24257_device { struct mutex lock; /* protect state data */ bool in_ilimit_autoset_disable; + bool pg_gpio_disable; }; static bool bq24257_is_volatile_reg(struct device *dev, unsigned int reg) @@ -356,7 +358,26 @@ static int bq24257_get_chip_state(struct bq24257_device *bq, state->fault = ret; - state->power_good = !gpiod_get_value_cansleep(bq->pg); + if (bq->pg_gpio_disable) + /* + * If we have a chip without a dedicated power-good GPIO or + * some other explicit bit that would provide this information + * assume the power is good if there is no supply related + * fault - and not good otherwise. There is a possibility for + * other errors to mask that power in fact is not good but this + * is probably the best we can do here. + */ + switch (state->fault) { + case FAULT_INPUT_OVP: + case FAULT_INPUT_UVLO: + case FAULT_INPUT_LDO_LOW: + state->power_good = false; + break; + default: + state->power_good = true; + } + else + state->power_good = !gpiod_get_value_cansleep(bq->pg); return 0; } @@ -725,6 +746,9 @@ static int bq24257_fw_probe(struct bq24257_device *bq) bq->init_data.in_ilimit_autoset_disable = device_property_read_bool( bq->dev, "ti,in-ilimit-autoset-disable"); + bq->init_data.pg_gpio_disable = device_property_read_bool( + bq->dev, "ti,pg-gpio-disable"); + return 0; } @@ -794,10 +818,22 @@ static int bq24257_probe(struct i2c_client *client, INIT_DELAYED_WORK(&bq->iilimit_setup_work, bq24257_iilimit_setup_work); - /* we can only check Power Good status by probing the PG pin */ - ret = bq24257_pg_gpio_probe(bq); - if (ret < 0) - return ret; + /* + * The BQ24250 doesn't have a dedicated Power Good (PG) pin so we + * explicitly disable this feature for this device and instead use + * a SW-based approach to determine the PG state. Note that the most + * reliable way to determine the PG state is through the use of the + * dedicated PG pin so on devices where it is available using that pin + * should be the method of choice. + */ + bq->pg_gpio_disable = bq->chip == BQ24250 ? + true : bq->init_data.pg_gpio_disable; + + if (!bq->pg_gpio_disable) { + ret = bq24257_pg_gpio_probe(bq); + if (ret < 0) + return ret; + } /* reset all registers to defaults */ ret = bq24257_field_write(bq, F_RESET, 1); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
