diff options
Diffstat (limited to 'drivers/iio/chemical')
| -rw-r--r-- | drivers/iio/chemical/bme680.h | 2 | ||||
| -rw-r--r-- | drivers/iio/chemical/bme680_core.c | 62 |
2 files changed, 56 insertions, 8 deletions
diff --git a/drivers/iio/chemical/bme680.h b/drivers/iio/chemical/bme680.h index 4edc5d21cb..f959252a4f 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 ef5e0e46fd..500f56834b 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> @@ -38,7 +39,7 @@ struct bme680_calib { s8 par_h3; s8 par_h4; s8 par_h5; - s8 par_h6; + u8 par_h6; s8 par_h7; s8 par_gh1; s16 par_gh2; @@ -342,10 +343,10 @@ static s16 bme680_compensate_temp(struct bme680_data *data, if (!calib->par_t2) bme680_read_calib(data, calib); - var1 = (adc_temp >> 3) - (calib->par_t1 << 1); + var1 = (adc_temp >> 3) - ((s32)calib->par_t1 << 1); var2 = (var1 * calib->par_t2) >> 11; var3 = ((var1 >> 1) * (var1 >> 1)) >> 12; - var3 = (var3 * (calib->par_t3 << 4)) >> 14; + var3 = (var3 * ((s32)calib->par_t3 << 4)) >> 14; data->t_fine = var2 + var3; calc_temp = (data->t_fine * 5 + 128) >> 8; @@ -368,9 +369,9 @@ static u32 bme680_compensate_press(struct bme680_data *data, var1 = (data->t_fine >> 1) - 64000; var2 = ((((var1 >> 2) * (var1 >> 2)) >> 11) * calib->par_p6) >> 2; var2 = var2 + (var1 * calib->par_p5 << 1); - var2 = (var2 >> 2) + (calib->par_p4 << 16); + var2 = (var2 >> 2) + ((s32)calib->par_p4 << 16); var1 = (((((var1 >> 2) * (var1 >> 2)) >> 13) * - (calib->par_p3 << 5)) >> 3) + + ((s32)calib->par_p3 << 5)) >> 3) + ((calib->par_p2 * var1) >> 1); var1 = var1 >> 18; var1 = ((32768 + var1) * calib->par_p1) >> 15; @@ -388,7 +389,7 @@ static u32 bme680_compensate_press(struct bme680_data *data, var3 = ((press_comp >> 8) * (press_comp >> 8) * (press_comp >> 8) * calib->par_p10) >> 17; - press_comp += (var1 + var2 + var3 + (calib->par_p7 << 7)) >> 4; + press_comp += (var1 + var2 + var3 + ((s32)calib->par_p7 << 7)) >> 4; return press_comp; } @@ -414,7 +415,7 @@ static u32 bme680_compensate_humid(struct bme680_data *data, (((temp_scaled * ((temp_scaled * calib->par_h5) / 100)) >> 6) / 100) + (1 << 14))) >> 10; var3 = var1 * var2; - var4 = calib->par_h6 << 7; + var4 = (s32)calib->par_h6 << 7; var4 = (var4 + ((temp_scaled * calib->par_h7) / 100)) >> 4; var5 = ((var3 >> 14) * (var3 >> 14)) >> 10; var6 = (var4 * var5) >> 1; @@ -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) { @@ -678,7 +720,7 @@ static int bme680_read_press(struct bme680_data *data, } *val = bme680_compensate_press(data, adc_press); - *val2 = 100; + *val2 = 1000; return IIO_VAL_FRACTIONAL; } @@ -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"); |