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 <dannenberg@xxxxxx>
---
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
--
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