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i2c-imc-skylake: the i2cdetect example shows what the driver does now

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The documentation's sample scan predates SPD instantiation at probe.  It
shows 0x36, 0x50 and 0x52 as detected addresses, but the driver claims
them itself now, so a real run reports UU there and 0x37 as well.  The
example printed output the driver can no longer produce.

Measured on the X299 system, both channels identical:

     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
20: -- -- -- -- -- -- -- 27 -- -- -- -- -- -- -- --
30: 30 31 -- -- 34 35 UU UU -- -- -- -- -- -- -- --
50: UU -- UU -- -- -- -- -- -- -- -- -- -- -- -- --

Say what the UU entries are, since the section that explains
instantiation comes further down and a reader scanning the bus meets
them first.
This commit is contained in:
Simone
2026-07-28 23:09:53 +02:00
parent 3de3131270
commit 6ae520c1ba
1 changed files with 7 additions and 2 deletions
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docs/submission/i2c-imc-skylake.rst
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@@ -112,8 +112,13 @@ read mode::
$ i2cdetect -y -r 6
0 1 2 3 4 5 6 7 8 9 a b c d e f
20: -- -- -- -- -- -- -- 27 -- -- -- -- -- -- -- --
30: 30 31 -- -- 34 35 36 -- -- -- -- -- -- -- -- --
50: 50 -- 52 -- -- -- -- -- -- -- -- -- -- -- -- --
30: 30 31 -- -- 34 35 UU UU -- -- -- -- -- -- -- --
50: UU -- UU -- -- -- -- -- -- -- -- -- -- -- -- --
The ``UU`` entries are the addresses the driver claims at probe: the SPD
EEPROMs at 0x50 and 0x52, and the page-select pair at 0x36 and 0x37 that
``i2c_register_spd_write_disable()`` reserves so that nothing can write them.
See "Instantiating clients" below.
Not advertising Quick is deliberate as well as accurate. A write to the
0x30-0x37 range is how an EE1004 SPD is write-protected, permanently on many