On Thu, Sep 22, 2022 at 2:34 PM Sakari Ailus
<sakari.ailus@xxxxxxxxxxxxxxx> wrote:
> On Thu, Sep 22, 2022 at 01:08:33PM +0100, Lad, Prabhakar wrote:
> > > > * Switched to manually turn ON/OFF the clocks instead of pm_runtime so that
> > > > the mipi/dhpy initialization happens as per the HW manual
> > >
> > > That doesn't look right. The driver doesn't use runtime PM anymore, so
> > > power domains may not be handled properly. What was the problem with
> > > clock handling using runtime PM ?
> > >
> > If we use the runtime PM all the clocks will be turned ON when we call
> > pm_runtime_resume_and_get() which I dont want to. As per the "Starting
> > reception for MIPI CSI-2 Input" section 35.3.1 for example we first
> > need to turn ON all the clocks and later further down the line we need
> > to just turn OFF VCLK -> Enable Link -> turn ON VCLK. Due to such
> > cases I have switched to individual clock handling.
>
> If that is the case, then you should control just that clock directly,
> outside runtime PM callbacks.
>
> Runtime PM may be needed e.g. for resuming a parent device.
Exactly.
So probably you should not consider R9A07G044_CRU_VCLK a PM clock,
i.e. you need changes to rzg2l_cpg_is_pm_clk() to exclude it.
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
