template replacement

[Patrick Venture]

On Mon, Aug 12, 2019 at 5:00 PM Patrick Venture <venture at google.com> wrote:
>
> On Mon, Aug 12, 2019 at 4:58 PM Ed Tanous <ed.tanous at intel.com> wrote:
> >
> > On 8/12/19 9:10 AM, Patrick Venture wrote:
> > > I've run into an issue and before I submitted a patch to solve my
> > > specific problem, I wanted to get a sense of what was intended:
> > >
> > > I have a field "name" that I want to set dynamically to "$bus_v2345_0_local"
> > > It finds the $bus match but then fails on the split.
> > > If I add a " " it then fails as well.
> > >
> >
> > Probably just a bug.  A quick scan of $bus in the configurations shows
> > that we've only ever used it in cases where it was the complete string
> > (ie "$bus") and even then, only used to populate numeric interfaces with
> > the bus number to be used programmatically by downstream sensors.
> >
> > Some of the intent was to largely remove the bus number from the device
> > naming convention, as outside the system the bus topology is largely
> > irrelevant.  With that said, I could see how that might be desired for
> > some setups.

To expand on this, I'm going to add a new template option "$slot"
that'll read the pcie-slot information from the device-tree and
convert the bus to the slot information, since that's semantically
more interesting.

>
> Yeah, I figured out it -- there's an assumption that a field has at
> least two other words other than $bus.
>
> So like "$bus card temp" will work -> "26_card_temp"
>
> But "$bus temp" will not -> "$bus_temp"
>
> If the field ends with "$bus" it'll just end up being that value as an
> int and lose the rest:
>
> "this that $bus" -> 26
>
> I haven't tried to debug the last case yet, and the names I'm using
> happen to be two extra words, so I can hold off on fixing that more
> generally -- i have a patch that should handle it, but haven't had a
> cycle to test it.
>
> >
> >
> > > It seems to be that if a template is at the end of the field, it works
> > > fine, otherwise it assumes there must be some operation to perform.
> > >
> > > Did you already have a fix in mind?
> >
> > James is out the next few days, so his answer might differ from mine
> > when he gets back, but I don't think we knew about this issue previously.