Re: [PATCH v2 3/4] checks: Warn on node name unit-addresses with '0x' or leading 0s

On Mon, Feb 13, 2017 at 02:11:57PM -0600, Rob Herring wrote:

On Sun, Feb 12, 2017 at 10:52 PM, David Gibson
[off-list ref] wrote:

quoted

On Fri, Feb 10, 2017 at 10:47:16AM -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.

Signed-off-by: Rob Herring <redacted>
---
v2:
- Split into separate check from unit_address_vs_reg

I'm still not thrilled with applying this test unconditionally -
especially when 4/4 introduces pretty much exactly the infrastructure
to do this better.  If you add a unit name formatter function to the
bus_type structure you really can then extend unit_address_vs_reg to
verify them against each other, which will cover this as well more
subtle mismatches.

Obviously it would only do it for known bus types - but adding a
"simple-bus" type would cover a lot of the cases, and a few for i2c
and spi would cover most of the rest.

Sigh. Around in circles we go. As we discussed before, this is simple,
but common problem check. It is not a complete check of the entire
unit-address.

Right.. and I'm saying why do that, when you're so close to having a
complete check of the entire unit address.

It only checks the first number (in case of ',') and
doesn't validate the number itself. While in theory we can conceive of
a unit-address that would be a problem for this check, we have not
identified one. It's not like there's lots of unknown cases here. We
know the buses that are out there for the most part. We can always
blacklist any problematic cases or turn off the check by default if
the need arises.

As far as bus types, I could easily support simple-bus, but there's no
way to identify i2c and spi (and others like mdio) buses reliably.
Maybe go off node names if we got those standardized, but I can't
check standard node names for the same reason.

Ah, ok, that makes things a bit more problematic.

Alright, I can live with this test if you turn it off for anything
that has a specific bus type identified.  i.e. specific bus types
should always have unit address checks which supersede this quick and
dirty one.


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