Re: [PATCH 2/2] Warn on node name unit-addresses with '0x' or leading 0s

On Mon, Feb 22, 2016 at 10:51:46AM -0600, Rob Herring wrote:

On Thu, Feb 18, 2016 at 11:07 PM, David Gibson
[off-list ref] wrote:

quoted

On Thu, Feb 11, 2016 at 02:46:59PM -0600, Rob Herring wrote:

quoted

Node name unit-addresses should never begin with 0x or leading 0s
regardless of whether they have a bus specific address (i.e. one with
commas) or not. Add warnings to check for these cases.

Hmm.. I'm pretty sure that's true in practice, but it's not true in
theory.  A bus could define it's unit address format just about
however it wants, including with leading 0s.

Only if it is not reviewed... This whole check is about what best
practices are, not what is possible.

Hmm.  dtc checks are really about checking for best practice at the
level of individual dts files, though, not bindings.

quoted

I think a better approach would be to add a test specific to
simple-bus devices (by looking at compatible on the parent) that fully
checks the unit address.

From there we can start adding tests for other bus types.

simple-bus is easy enough,

So, start with that, then tackle the next problem.

but then next up would be I2C and SPI. We
can't generically tell if a node is on I2C or SPI bus.

Why not?  Or perhaps.. how generically do you need?  I think having a
big list of i2c / spi controllers would be acceptable here, if not
ideal.

If we do have
some bus with wacky addresses, it should definitely have a bus
compatible and then we can simply exclude it from the check.

Another option would be skipping the test if there are any commas (or
periods, etc.) in the unit address. That's pretty rare to begin with
and a single number is pretty much not a bus specific unit-address.

Um.. no.. there are definitely bus types that don't typically use
commas.  ISA, for one.

-- 
David Gibson			| I'll have my music baroque, and my code
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				| _way_ _around_!
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