Re: MCP9808 iio or hwmon

[Alison Schofield <amsfield22@gmail.com>]

On Tue, Jun 21, 2016 at 04:42:46PM -0700, Guenter Roeck wrote:
> On Tue, Jun 21, 2016 at 03:26:11PM -0700, Alison Schofield wrote:
> > On Tue, Jun 14, 2016 at 06:27:50AM -0700, Guenter Roeck wrote:
> > > On 06/14/2016 01:22 AM, Daniel Baluta wrote:
> > > >[fixing IIO, hwmon lists emails]
> > > >
> > > >On Tue, Jun 14, 2016 at 11:20 AM, Daniel Baluta <daniel.baluta@gmail.com> wrote:
> > > >>On Tue, Jun 14, 2016 at 1:08 AM, Alison Schofield <amsfield22@gmail.com> wrote:
> > > >>>
> > > >>>I was working on an iio driver for MCP9808 when Jonathan took notice
> > > >>>and suggested we have the iio or hwmon discussion.
> > > >>>
> > > >>>So, where should this sensor driver reside?
> > > >>>
> > > >>>http://ww1.microchip.com/downloads/en/DeviceDoc/25095A.pdf
> > > >>>
> > > >>>It's a digital temp sensor with user programmable registers for
> > > >>>sensing applications.  Supports shutdown, low power modes,
> > > >>>specifying of event & critical output boundaries.  Can support
> > > >>>8 sensors on a single serial bus. Touted as 'ideal for sophisticated
> > > >>>multi-zone temperature-monitoring applications.'
> > > >>
> > > >>This is debatable, looking to the datasheet this driver could reside
> > > >>in both places.
> > > >>
> > > >>Because this sensor has Industrial utility (e.g freezers, refrigerators) I
> > > >>am inclined to say we should support it in IIO.
> > > >>
> > > 
> > > Literally every sensor has that utility.
> > > 
> > > Alternatively, you might consider adding its device ID to the jc42 driver.
> > > If you want to be fancy, you could add optional support for resolution
> > > selection to the driver.
> > > 
> > > Guenter
> > 
> > Hi Guenter,
> > I'm using the mcp9808 with the jc42 driver by instantiating it.
> > 
> > I've added the device ID info so that the .detect callback can recognize
> > it, but can't figure out how to test that.  When/how does that .detect
> > get called?  I am using the Diolan.
> > 
> Not sure if it works, but try to load the the jc42 driver using modprobe
> first, and _then_ insert the diolan adapter.
> 
> Guenter

Finally got it!  I had to add I2C_CLASS_SPD (jc42's class) to Diolan and
then follow the order you suggested.