On Fri, Feb 17, 2023 at 3:33 PM Christian Kohlschütter <christian@xxxxxxxxxxxxxxxx> wrote: > > On 18. Feb 2023, at 00:22, Saravana Kannan <saravanak@xxxxxxxxxx> wrote: > > > > On Thu, Aug 25, 2022 at 2:28 PM Christian Kohlschütter > > <christian@xxxxxxxxxxxxxxxx> wrote: > >> > >> Previously, an unresolved regulator supply reference upon calling > >> regulator_register on an always-on or boot-on regulator caused > >> set_machine_constraints to be called twice. > >> > >> This in turn may initialize the regulator twice, leading to voltage > >> glitches that are timing-dependent. A simple, unrelated configuration > >> change may be enough to hide this problem, only to be surfaced by > >> chance. > > > > In your case, can you elaborate which part of the constraints/init > > twice caused the issue? > > > > I'm trying to simplify some of the supply resolving code and I'm > > trying to not break your use case. > > > > -Saravana > > Here's a write-up of my use case, and how we got to the solution: > https://kohlschuetter.github.io/blog/posts/2022/10/28/linux-nanopi-r4s/ I did read the write up before I sent my request. I'm asking for specifics on which functions in the set_machine_constraints() was causing the issue. And it's also a bit unclear to me if the issue was with having stuff called twice on the alway-on regulator or the supply. -Saravana
