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Date: Thu, 4 Jan 2024 15:40:44 +0200
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Subject: Re: i2c-designware: NULL ptr at RIP: 0010:regmap_read+0x12/0x70
To: "V, Narasimhan" <Narasimhan.V@amd.com>, Borislav Petkov <bp@alien8.de>,
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On 1/4/24 08:35, V, Narasimhan wrote:
>> [    6.245173] i2c_designware AMDI0010:00: Unknown Synopsys component type: 0xffffffff
> 
> This made me scratching my head since driver probing will fail in this
> case with -ENODEV and I could not trigger runtime PM activity in such
> case but perhaps this is timing specific which happens to happen in your
> case.
> 
> Out of curiosity do you see this same "i2c_designware AMDI0010:00:
> Unknown Synopsys component type: 0xffffffff" error on Vanilla or is it
> also regression in linux-next?
> 
> This does not happen on Vanilla, only on linux-next.
> 
This is even more strange. Controller is in reset but I'm blind to see 
from Andy's patches why. Do you have change to test at these commits?

bd466a892612 ("i2c: designware: Fix PM calls order in dw_i2c_plat_probe()")
c012fde343d2 ("i2c: designware: Fix reset call order in dw_i2c_plat_probe()"

and maybe the last one
4bff054b64e1 ("i2c: designware: Fix spelling and other issues in the 
comments")

I'm trying to narrow does the regression come from first two patches and 
if not, then test the last one.

Andy is out of office and if we can narrow the regression to first two 
patches we perhaps can revert just them and otherwise need to drop the 
whole set.