Re: [PATCH v2 0/4] PCI: rcar, rcar-gen2: More Gen2 compatibility strings

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Dec 11, 2015 at 11:14:34AM +0900, Simon Horman wrote:
> On Wed, Dec 09, 2015 at 12:37:43PM -0600, Bjorn Helgaas wrote:
> > On Thu, Dec 03, 2015 at 07:51:36AM +0900, Simon Horman wrote:
> > > Hi,
> > > 
> > > this short series adds generic gen2 and SoC-specific r8a7793 compatibility
> > > strings to the rcar PCI and rcar-gen2 PCIE drivers. The intention is to
> > > provide a complete set of compatibility strings for known Gen2 SoCs.
> > > 
> > > Key Changes in v2:
> > > * Include "rcar-" in generic bindings
> > > 
> > > Simon Horman (4):
> > >   PCI: rcar-gen2: add gen2 fallback compatibility string
> > >   PCI: rcar-gen2: add device tree support for r8a7793
> > >   PCI: rcar: add gen2 fallback compatibility string
> > >   PCI: rcar: add device tree support for r8a7793
> > > 
> > >  Documentation/devicetree/bindings/pci/pci-rcar-gen2.txt | 12 ++++++++++--
> > >  Documentation/devicetree/bindings/pci/rcar-pci.txt      | 14 +++++++++++---
> > >  drivers/pci/host/pci-rcar-gen2.c                        |  1 +
> > >  drivers/pci/host/pcie-rcar.c                            |  1 +
> > >  4 files changed, 23 insertions(+), 5 deletions(-)
> > 
> > I applied these:
> > 
> > >   PCI: rcar-gen2: add gen2 fallback compatibility string
> > >   PCI: rcar: add gen2 fallback compatibility string
> > 
> > to pci/host-rcar for v4.5, thanks!
> > 
> > I haven't applied the R8A7793 binding documentation updates yet, but
> > I'll be happy to do so given a short description of why they're
> > useful (since they don't update a DT or the driver).  Or they could be
> > merged via a DT tree.
> 
> To clarify: you would like a description in the changelog?

Yes, please.  The email discussion so far hasn't contained what I'm
looking for (if it had, I would have just inserted it and been done
with it).

Apparently it has to do with the stable DT rules, which I don't know.
A concrete example would probably help clear it up.

I've applied the parts that touch PCI.  I won't be offended if the
binding documentation patches go as-is via another tree.  It's just
that if *I'm* going to apply them, I'd like to understand better what
the benefit is.

Bjorn