Re: [PATCH v2 2/7] iio: pressure: bmp280: Add support for bmp280 soft reset

Jonathan Cameron
2024-07-28T15:49:12Z

On Fri, 26 Jul 2024 01:10:34 +0200
Vasileios Amoiridis <vassilisamir@gmail.com> wrote:

> 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>
Trivial passing comment seeing as you are going do be doing a v3 anyway.

Jonathan

> ---
> drivers/iio/pressure/bmp280-core.c | 28 ++++++++++++++++++++++++++++
> drivers/iio/pressure/bmp280.h | 3 +++
> 2 files changed, 31 insertions(+)
>
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index d5e5eb22667a..acbc33aacc09 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -963,6 +963,32 @@ static const unsigned long bme280_avail_scan_masks[] = {
> 0
> };
>
> +static int bmp280_preinit(struct bmp280_data *data)
> +{
> + unsigned int reg;
> + int ret;
> +
> + ret = regmap_write(data->regmap, BMP280_REG_RESET, BMP280_RST_SOFT_CMD);
> + if (ret) {
> + dev_err(data->dev, "Failed to reset device.\n");
> + return ret;
Is this only ever called from probe?

If so, return dev_err_probe() which will save a few lines of code.

> + }
> +
> + usleep_range(data->start_up_time, data->start_up_time + 500);
> +
> + ret = regmap_read(data->regmap, BMP280_REG_STATUS, &reg);
> + if (ret) {
> + dev_err(data->dev, "Failed to read status register.\n");
> + return ret;
> + }
> + if (reg & BMP280_REG_STATUS_IM_UPDATE) {
> + dev_err(data->dev, "Failed to copy NVM contents.\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int bmp280_chip_config(struct bmp280_data *data)
> {
> u8 osrs = FIELD_PREP(BMP280_OSRS_TEMP_MASK, data->oversampling_temp + 1) |
> @@ -1079,6 +1105,7 @@ 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,
> };
> @@ -1196,6 +1223,7 @@ 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,
> };
> diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
> index 9bea0b84d2f4..a9f220c1f77a 100644
> --- a/drivers/iio/pressure/bmp280.h
> +++ b/drivers/iio/pressure/bmp280.h
> @@ -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