Re: [PATCH v2] hwmon: (sht3x) add devicetree support

[Guenter Roeck <linux@roeck-us.net>]

On Mon, Oct 15, 2018 at 07:55:58AM +0200, Wojciech Sleńska wrote:
> pt., 12 paź 2018 o 22:28 Rob Herring <robh@kernel.org> napisał(a):
> >
> > On Fri, Oct 05, 2018 at 07:38:35AM +0200, Wojciech Slenska wrote:
> >
> > Commit msg?
> >
> > > Signed-off-by: Wojciech Slenska <wojciech.slenska@gmail.com>
> > > ---
> > >  Documentation/devicetree/bindings/hwmon/sht3x.txt | 16 +++++++++++++
> >
> > Please split bindings to separate patch.
> 
> I will do this.
> 
> >
> > >  drivers/hwmon/sht3x.c                             | 28 ++++++++++++++++++++---
> > >  2 files changed, 41 insertions(+), 3 deletions(-)
> > >  create mode 100644 Documentation/devicetree/bindings/hwmon/sht3x.txt
> > >
> > > diff --git a/Documentation/devicetree/bindings/hwmon/sht3x.txt b/Documentation/devicetree/bindings/hwmon/sht3x.txt
> > > new file mode 100644
> > > index 0000000..80b117e
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/hwmon/sht3x.txt
> > > @@ -0,0 +1,16 @@
> > > +Sensirion SHT3x Humidity and Temperature Sensor
> > > +
> > > +Required node properties:
> > > +- compatible: "sensirion,sht3x" or "sensirion,sts3x"
> > > +- reg: I2C bus address of the device
> > > +
> > > +Optional properties:
> > > +- sensirion,blocking-io: enable blocking mode on i2c
> >
> > This is not a h/w parameter and shouldn't be in DT.
> >
> > > +- sensirion,no-high-precision: disable high accuracy
> >
> > Maybe this one is okay, but couldn't the user want to set this? If so,
> > then it should be a sysfs attr.
> 
> Those two parameters have been just moved from
> linux/include/linux/platform_data/sht3x.h
> Currently, those two parameters can be set in board file, so for me
> was natural to move it to dts.
> Of course, I can remove it from dts completely.
> 

I wonder if there is an authoritative document explaining the current policy
in respect to devicetree properties. Sometimes I hear that platform
configuration parameters are now permitted, sometimes I hear that we are
back to hardware description only.

Guenter

> >
> > > +
> > > +Example sht3x node:
> > > +
> > > +sensor {
> >
> > sensor@4a
> >
> 
> I will fix this.
> 
> > > +     compatible = "sensirion,sht3x";
> > > +     reg = <0x4a>;
> > > +}
> >
> 
> BR
> Wojciech Slenska