Re: [PATCH 0/9] driver core / pmdomain: Add support for fined grained sync_state

Hi Ulf,

On Tue, 3 Mar 2026 at 14:23, Ulf Hansson [off-list ref] wrote:

Since the introduction [1] of the common sync_state support for pmdomains
(genpd), we have encountered a lot of various interesting problems. In most
cases the new behaviour of genpd triggered some weird platform specific bugs.

That said, in LPC in Tokyo me and Saravana hosted a session to walk through the
remaining limitations that we have found for genpd's sync state support. In
particular, we discussed the problems we have for the so-called onecell power
domain providers, where a single provider typically provides multiple
independent power domains, all with their own set of consumers.

In these cases, the generic sync_state mechanism with fw_devlink isn't fine
grained enough, as we end up waiting for all consumers for all power domains
before the ->sync_callback gets called for the supplier/provider. In other
words, we may end up keeping unused power domains powered-on, for no good
reasons.

The series intends to fix this problem. Please have a look at the commit
messages for more details.

Thanks for your series!

I gave it a try on various R-Car and R/SH-Mobile platforms, and all
PM Domains are handled fine.
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds