Re: [PATCH v2 3/5] iio: pressure: bmp280: Add support for new sensor BMP580

Angel Iglesias
2022-12-29T18:23:28Z

On Thu, 2022-12-29 at 18:35 +0100, Christophe JAILLET wrote:
> Le 26/12/2022 à 15:29, Angel Iglesias a écrit :
> > Adds compatibility with the new sensor generation, the BMP580.
> >
> > The measurement and initialization codepaths are adapted from
> > the device datasheet and the repository from manufacturer at
> > https://github.com/boschsensortec/BMP5-Sensor-API.
> >
> > Signed-off-by: Angel Iglesias
> > <ang.iglesiasg-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> >
>
> [...]
>
> > diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
> > index efc31bc84708..27d2abc17d01 100644
> > --- a/drivers/iio/pressure/bmp280.h
> > +++ b/drivers/iio/pressure/bmp280.h
>
> [...]
>
> > +#define BMP580_CHIP_ID                 0x50
> >   #define BMP380_CHIP_ID                        0x50
>
> Hi,
>
> this is maybe correct (I've not been able to find the datasheet to check
> myself), but it looks odd to have the same ID for 2 different chips.

Yes, I also couldn't find a datasheet for the BMP580 or a devkit anywhere. I'm
developing this using the BMP581, which seems to be a variant almost identical.
Something similar happened with the BMP38x; you could find the BMP384 and the
BMP388, but the BMP380 was unavailable everywhere, datasheet included. My guess
is this is a similar situation. In any case, the datasheet of the BMP581 is
available here:
https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp581-ds004.pdf

Regarding the chip id being the same between generations is weird, but at least
the datasheet and the sensor I have uses 0x50 as the chip id. After you
mentioned this, I checked back on the reference API repository from Bosch and it
has both 0x50 and 0x51 as valid IDs:
* https://github.com/boschsensortec/BMP5-Sensor-API/blob/master/bmp5_defs.h#L198
* https://github.com/boschsensortec/BMP5-Sensor-API/blob/master/bmp5.c#L1444

Angel

> CJ
>
> >   #define BMP180_CHIP_ID                        0x55
> >   #define BMP280_CHIP_ID                        0x58
>