Hi Eugeniu, On Wed, May 27, 2020 at 9:16 AM Eugeniu Rosca <erosca@xxxxxxxxxxxxxx> wrote: > On Tue, Oct 15, 2019 at 12:46:13PM +0200, Jacopo Mondi wrote: > > CMM functionalities are retained between suspend/resume cycles (tested with > > suspend-to-idle) without requiring a re-programming of the LUT tables. > > Hmm. Is this backed up by any statement in the HW User's manual? > This comes in contrast with the original Renesas CMM implementation [**] > which does make use of suspend (where the freeze actually happens). > > Can we infer, based on your statement, that we could also get rid of > the suspend callback in [**]? While the CMM state will be retained across suspend-to-idle, I'm quite sure it will be lost by suspend-to-RAM, at least on the Salvator-X(S), ULCB, and Ebisu development boards, as PSCI will ask the BD9571WMV regulator to power down the R-Car SoC. So IMHO we do need suspend/resume handling. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx 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