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

Vasileios Amoiridis
2024-08-21T21:32:36Z

On Sun, Jul 28, 2024 at 04:49:01PM +0100, Jonathan Cameron wrote:
> 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.
>

Hi Jonathan,

Indeed, this is being called only from probe so I could change that as you
proposed!

Cheers,
Vasilis

> > + }
> > +
> > + 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
>