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

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 29 Dec 2022 19:23:16 +0100
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> 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
https://github.com/boschsensortec/BMP3-Sensor-API/blob/master/bmp3_defs.h
I was curious on whether we had a wrong value for bmp380, but nope... Same ID.

Huh. As per earlier comment - who wants to moan at Bosch as this is crazy situation?

Jonathan


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