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-rw-r--r--drivers/iio/chemical/bme680.h2
-rw-r--r--drivers/iio/chemical/bme680_core.c46
2 files changed, 48 insertions, 0 deletions
diff --git a/drivers/iio/chemical/bme680.h b/drivers/iio/chemical/bme680.h
index 4edc5d21cb9f..f959252a4fe6 100644
--- a/drivers/iio/chemical/bme680.h
+++ b/drivers/iio/chemical/bme680.h
@@ -54,7 +54,9 @@
#define BME680_NB_CONV_MASK GENMASK(3, 0)
#define BME680_REG_MEAS_STAT_0 0x1D
+#define BME680_NEW_DATA_BIT BIT(7)
#define BME680_GAS_MEAS_BIT BIT(6)
+#define BME680_MEAS_BIT BIT(5)
/* Calibration Parameters */
#define BME680_T2_LSB_REG 0x8A
diff --git a/drivers/iio/chemical/bme680_core.c b/drivers/iio/chemical/bme680_core.c
index 5db48f6d646c..500f56834b01 100644
--- a/drivers/iio/chemical/bme680_core.c
+++ b/drivers/iio/chemical/bme680_core.c
@@ -10,6 +10,7 @@
*/
#include <linux/acpi.h>
#include <linux/bitfield.h>
+#include <linux/delay.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/log2.h>
@@ -532,6 +533,43 @@ static u8 bme680_oversampling_to_reg(u8 val)
return ilog2(val) + 1;
}
+/*
+ * Taken from Bosch BME680 API:
+ * https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x.c#L490
+ */
+static int bme680_wait_for_eoc(struct bme680_data *data)
+{
+ struct device *dev = regmap_get_device(data->regmap);
+ unsigned int check;
+ int ret;
+ /*
+ * (Sum of oversampling ratios * time per oversampling) +
+ * TPH measurement + gas measurement + wait transition from forced mode
+ * + heater duration
+ */
+ int wait_eoc_us = ((data->oversampling_temp + data->oversampling_press +
+ data->oversampling_humid) * 1936) + (477 * 4) +
+ (477 * 5) + 1000 + (data->heater_dur * 1000);
+
+ usleep_range(wait_eoc_us, wait_eoc_us + 100);
+
+ ret = regmap_read(data->regmap, BME680_REG_MEAS_STAT_0, &check);
+ if (ret) {
+ dev_err(dev, "failed to read measurement status register.\n");
+ return ret;
+ }
+ if (check & BME680_MEAS_BIT) {
+ dev_err(dev, "Device measurement cycle incomplete.\n");
+ return -EBUSY;
+ }
+ if (!(check & BME680_NEW_DATA_BIT)) {
+ dev_err(dev, "No new data available from the device.\n");
+ return -ENODATA;
+ }
+
+ return 0;
+}
+
static int bme680_chip_config(struct bme680_data *data)
{
struct device *dev = regmap_get_device(data->regmap);
@@ -622,6 +660,10 @@ static int bme680_read_temp(struct bme680_data *data, int *val)
if (ret < 0)
return ret;
+ ret = bme680_wait_for_eoc(data);
+ if (ret)
+ return ret;
+
ret = regmap_bulk_read(data->regmap, BME680_REG_TEMP_MSB,
&tmp, 3);
if (ret < 0) {
@@ -738,6 +780,10 @@ static int bme680_read_gas(struct bme680_data *data,
if (ret < 0)
return ret;
+ ret = bme680_wait_for_eoc(data);
+ if (ret)
+ return ret;
+
ret = regmap_read(data->regmap, BME680_REG_MEAS_STAT_0, &check);
if (check & BME680_GAS_MEAS_BIT) {
dev_err(dev, "gas measurement incomplete\n");