Re: i2c-designware: NULL ptr at RIP: 0010:regmap_read+0x12/0x70

From: Jarkko Nikula
Date: Thu Jan 04 2024 - 08:40:56 EST


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.