I had a chance to sit back down with the machine.  I didn't take it all the way apart - there are pieces that I'm afraid of breaking without directions on how to properly disassemble them.

However, I did recover an exact chip ID - the chips in use are BMA255s [1].  Rather than take the machine apart (and because the chips are 2mmx2mm), I queried the chip over SMBus.  On page 50 of the below document, you can see that register 0x00 is a read-only chip ID.  This chipID is unique per Bosch product.  So, using SMBus, I asked the chip for it's chip ID (0xFA, in this case) and then searched likely products until I found the matching chipID.

Does this suffice to settle which chips are in use?  If not, I can finish taking the machine apart, I'd just prefer to avoid the risk of breaking something.

As soon as I finish screwing everything back together, I'll grab the other software IDs asked for and build the branch referenced elsewhere.



On 01/30/2018 03:12 PM, Andy Shevchenko wrote:
On Tue, Jan 30, 2018 at 9:27 PM, Steven Presser <> wrote:
On 01/30/2018 02:05 PM, Andy Shevchenko wrote:
On Tue, Jan 30, 2018 at 8:34 PM, Steven Presser <>
First, I believe the "bmc150" in the subject line is in some way a
You'd have to ask Jeremy for more details on what he intended it to refer
to.  However, I believe the device in question is actually the bma250[1],
which does not have a magnetometer component.  I'm unfortunately away
my notes, but I can check later if you need me to verify the exact chip.
Please do, I would really be on the safe side here.
Will do.  My digital notes indicate I worked from what was exposed back to
what chip matched.  If you can give me through Friday evening, I'll crack it
and do a visual verification.  (Alas, I'm traveling and won't be back to it
until then).
We are in the merge window anyway, so, no hurry.

I'm looking right now in the clean solution. Looks promising.

Bad, bad Lenovo. (DMI strings might help here)
What particular DMI strings would be helpful?  All of them?
Let's do this way. Create a bug on kernel bugzilla, attach output of

% acpidump -o tables.dat # tables.dat file
% grep -H 15 /sys/bus/acpi/devices/*/status
% dmidecode

and share the number here. I will take it.

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

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