diff options
author | Vasileios Amoiridis <vassilisamir@gmail.com> | 2024-11-02 14:13:08 +0100 |
---|---|---|
committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2024-11-03 20:33:45 +0000 |
commit | 56686ac80b859c2049cc372f7837470aa71c98cf (patch) | |
tree | b2d914c2a480b82c4e056598bcfe0016de92a35c /drivers/iio | |
parent | 80b9f3a80e6e23d91aaca5ece28cd5710d5ad715 (diff) | |
download | linux-stable-56686ac80b859c2049cc372f7837470aa71c98cf.tar.gz linux-stable-56686ac80b859c2049cc372f7837470aa71c98cf.tar.bz2 linux-stable-56686ac80b859c2049cc372f7837470aa71c98cf.zip |
iio: chemical: bme680: Add support for preheat current
Add functionality to inject a specified amount of current to the heating
plate before the start of the gas measurement to allow the sensor to reach
faster to the requested temperature.
Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
Link: https://patch.msgid.link/20241102131311.36210-5-vassilisamir@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio')
-rw-r--r-- | drivers/iio/chemical/bme680.h | 1 | ||||
-rw-r--r-- | drivers/iio/chemical/bme680_core.c | 41 |
2 files changed, 42 insertions, 0 deletions
diff --git a/drivers/iio/chemical/bme680.h b/drivers/iio/chemical/bme680.h index a0a7794543c8..00ab89b3138b 100644 --- a/drivers/iio/chemical/bme680.h +++ b/drivers/iio/chemical/bme680.h @@ -42,6 +42,7 @@ #define BME680_RHRANGE_MASK GENMASK(5, 4) #define BME680_REG_RES_HEAT_VAL 0x00 #define BME680_RSERROR_MASK GENMASK(7, 4) +#define BME680_REG_IDAC_HEAT_0 0x50 #define BME680_REG_RES_HEAT_0 0x5A #define BME680_REG_GAS_WAIT_0 0x64 #define BME680_ADC_GAS_RES GENMASK(15, 6) diff --git a/drivers/iio/chemical/bme680_core.c b/drivers/iio/chemical/bme680_core.c index 34ce29fdc722..9783953e64e0 100644 --- a/drivers/iio/chemical/bme680_core.c +++ b/drivers/iio/chemical/bme680_core.c @@ -118,6 +118,7 @@ struct bme680_data { u8 oversampling_temp; u8 oversampling_press; u8 oversampling_humid; + u8 preheat_curr_mA; u16 heater_dur; u16 heater_temp; @@ -214,6 +215,12 @@ static const struct iio_chan_spec bme680_channels[] = { }, }, IIO_CHAN_SOFT_TIMESTAMP(4), + { + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .output = 1, + .scan_index = -1, + }, }; static int bme680_read_calib(struct bme680_data *data, @@ -561,6 +568,12 @@ static u8 bme680_calc_heater_dur(u16 dur) return durval; } +/* Taken from datasheet, section 5.3.3 */ +static u8 bme680_calc_heater_preheat_current(u8 curr) +{ + return 8 * curr - 1; +} + static int bme680_set_mode(struct bme680_data *data, enum bme680_op_mode mode) { struct device *dev = regmap_get_device(data->regmap); @@ -659,6 +672,20 @@ static int bme680_chip_config(struct bme680_data *data) return 0; } +static int bme680_preheat_curr_config(struct bme680_data *data, u8 val) +{ + struct device *dev = regmap_get_device(data->regmap); + u8 heatr_curr; + int ret; + + heatr_curr = bme680_calc_heater_preheat_current(val); + ret = regmap_write(data->regmap, BME680_REG_IDAC_HEAT_0, heatr_curr); + if (ret < 0) + dev_err(dev, "failed to write idac_heat_0 register\n"); + + return ret; +} + static int bme680_gas_config(struct bme680_data *data) { struct device *dev = regmap_get_device(data->regmap); @@ -687,6 +714,10 @@ static int bme680_gas_config(struct bme680_data *data) return ret; } + ret = bme680_preheat_curr_config(data, data->preheat_curr_mA); + if (ret) + return ret; + /* Enable the gas sensor and select heater profile set-point 0 */ ret = regmap_update_bits(data->regmap, BME680_REG_CTRL_GAS_1, BME680_RUN_GAS_MASK | BME680_NB_CONV_MASK, @@ -939,6 +970,15 @@ static int bme680_write_raw(struct iio_dev *indio_dev, return bme680_chip_config(data); } + case IIO_CHAN_INFO_PROCESSED: + { + switch (chan->type) { + case IIO_CURRENT: + return bme680_preheat_curr_config(data, (u8)val); + default: + return -EINVAL; + } + } default: return -EINVAL; } @@ -1072,6 +1112,7 @@ int bme680_core_probe(struct device *dev, struct regmap *regmap, data->oversampling_temp = 8; /* 8X oversampling rate */ data->heater_temp = 320; /* degree Celsius */ data->heater_dur = 150; /* milliseconds */ + data->preheat_curr_mA = 0; ret = regmap_write(regmap, BME680_REG_SOFT_RESET, BME680_CMD_SOFTRESET); if (ret < 0) |