Hi Rob

On Thu, 29 Jan 2015, Rob Herring wrote:

On Wed, Jan 28, 2015 at 5:49 PM, Paul Walmsley [off-list ref] wrote:

quoted

Add compatible strings for the PCIe IP blocks present on several Tegra
chips.  The primary objective here is to avoid checkpatch warnings,
per:

http://marc.info/?l=linux-tegra&m=142201349727836&w=2

Signed-off-by: Paul Walmsley <redacted>
Cc: Thierry Reding <redacted>
Cc: Rob Herring <redacted>
Cc: Pawel Moll <redacted>
Cc: Mark Rutland <redacted>
Cc: Ian Campbell <redacted>
Cc: Kumar Gala <redacted>
Cc: Stephen Warren <redacted>
Cc: Alexandre Courbot <redacted>
Cc: linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
 .../bindings/pci/nvidia,tegra20-pcie.txt           |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt b/Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt
index d763e047c6ae..e772884f1c33 100644
--- a/Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt

@@ -5,6 +5,8 @@ Required properties:
   - "nvidia,tegra20-pcie"
   - "nvidia,tegra30-pcie"
   - "nvidia,tegra124-pcie"
+  - "nvidia,tegra132-pcie" (not yet matched in the driver)
+  - "nvidia,tegra210-pcie" (not yet matched in the driver)

Whether the driver matches or not is irrelevant to the binding and may
change over time. Does this mean the driver matches on something else
or Tegra132 is not yet supported in the driver? 

It means that the driver currently matches on one of the first three 
strings that don't carry that annotation.

If the former, what is important is what are the valid combinations of 
compatible properties and that is not captured here. In other words, 
what is the fallback compatible string for each chip?

The intention was to try to be helpful: to document that anyone adding a 
"nvidia,tegra132-pcie" compatible string would also need to add one of the 
other strings as a fallback.  Would you like that to be documented in a 
different way, or removed?


- Paul