@@ -964,6 +964,33 @@ static const unsigned long bme280_avail_scan_masks[] = {
0
};
+static int bmp280_preinit(struct bmp280_data *data)
+{
+ struct device *dev = data->dev;
+ unsigned int reg;
+ int ret;
+
+ ret = regmap_write(data->regmap, BMP280_REG_RESET, BMP280_RST_SOFT_CMD);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to reset device.\n");
+
+ /*
+ * According to the datasheet in Chapter 1: Specification, Table 2,
+ * after resetting, the device uses the complete power-on sequence so
+ * it needs to wait for the defined start-up time.
+ */
+ fsleep(data->start_up_time);
+
+ ret = regmap_read(data->regmap, BMP280_REG_STATUS, ®);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to read status register.\n");
+
+ if (reg & BMP280_REG_STATUS_IM_UPDATE)
+ return dev_err_probe(dev, -EIO, "Failed to copy NVM contents.\n");
+
+ return 0;
+}
+
static int bmp280_chip_config(struct bmp280_data *data)
{
u8 osrs = FIELD_PREP(BMP280_OSRS_TEMP_MASK, data->oversampling_temp + 1) |
@@ -1081,6 +1108,7 @@ const struct bmp280_chip_info bmp280_chip_info = {
.read_temp = bmp280_read_temp,
.read_press = bmp280_read_press,
.read_calib = bmp280_read_calib,
+ .preinit = bmp280_preinit,
.trigger_handler = bmp280_trigger_handler,
};
@@ -1201,6 +1229,7 @@ const struct bmp280_chip_info bme280_chip_info = {
.read_press = bmp280_read_press,
.read_humid = bme280_read_humid,
.read_calib = bme280_read_calib,
+ .preinit = bmp280_preinit,
.trigger_handler = bme280_trigger_handler,
};
@@ -205,6 +205,9 @@
#define BMP280_REG_CONFIG 0xF5
#define BMP280_REG_CTRL_MEAS 0xF4
#define BMP280_REG_STATUS 0xF3
+#define BMP280_REG_STATUS_IM_UPDATE BIT(0)
+#define BMP280_REG_RESET 0xE0
+#define BMP280_RST_SOFT_CMD 0xB6
#define BMP280_REG_COMP_TEMP_START 0x88
#define BMP280_COMP_TEMP_REG_COUNT 6
The BM(P/E)28x devices have an option for soft reset which is also recommended by the Bosch Sensortech BME2 Sensor API to be used before the initial configuration of the device. Link: https://github.com/boschsensortec/BME280_SensorAPI/blob/bme280_v3.5.1/bme280.c#L429 Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com> --- drivers/iio/pressure/bmp280-core.c | 29 +++++++++++++++++++++++++++++ drivers/iio/pressure/bmp280.h | 3 +++ 2 files changed, 32 insertions(+)