Re: [PATCH v7 7/8] clk: qcom: dispcc-sm8250: stop using mmcx regulator

Dmitry Baryshkov
2021-10-15T00:15:58Z

On Fri, 15 Oct 2021 at 03:04, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Dmitry Baryshkov (2021-10-14 02:53:41)
> > On 13/10/2021 22:50, Stephen Boyd wrote:
> > > Quoting Dmitry Baryshkov (2021-10-07 09:16:13)
> > >> On 07/10/2021 18:48, Bjorn Andersson wrote:
> > >>> On Sun 29 Aug 08:47 PDT 2021, Dmitry Baryshkov wrote:
> > >>>
> > >>>> Now as the common qcom clock controller code has been taught about power
> > >>>> domains, stop mentioning mmcx supply as a way to power up the clock
> > >>>> controller's gdsc.
> > >>>>
> > >>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > >>>> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> > >>>
> > >>> Once we merge these, I expect that the boards will start crashing if
> > >>> the kernel is booted using an existing DTB?
> > >>>
> > >>> Is it okay to just merge the first 6 patches in the series now and
> > >>> postpone these two until we've had the dts change sitting for a while?
> > >>
> > >> Sure it is.
> > >>
> > >
> > > What's the merge strategy? It goes through arm-soc?
> >
> > I think this should go through the clk tree. There is little chance of
> > conflicts.
> >
>
> The other thing that concerns me is that we don't have backwards
> compat code. If things are going to start crashing that's not very nice.
> Is there some way to make it work with old and new DTB for one release
> so that we don't have to worry about this problem?

I have to admit that I did not check that, but without the patch 7 the
dispcc and videocc would be compatible with the old DTB. The 'supply =
"mmcx"' would ensure that it is used if it is defined.

--
With best wishes
Dmitry