Quoting Dmitry Baryshkov (2020-10-05 15:59:13)
> On SM8250 MDSS_GDSC (and respective dispcc clocks) are children of MMCX
> power domain. MMCX needs to be enabled to be able to access GDSC
> registers and to enable display clocks. Use dev_pm/opp to enable
> corresponding power domain.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> ---
A general question is why is this done in the gdsc code instead of
somewhere generic? It seems that genpds may need to change the
performance state of other genpds. I vaguely recall that genpd supports
connecting different power domains together so maybe this could all be
handled in the genpd layer instead of here? Then a regulator could be
put behind a genpd and similarly be connected to the gdsc and turned on
before turning on the gdsc?
> drivers/clk/qcom/gdsc.c | 56 ++++++++++++++++++++++++++++++++++++++---
> drivers/clk/qcom/gdsc.h | 5 ++++
> 2 files changed, 57 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/clk/qcom/gdsc.h b/drivers/clk/qcom/gdsc.h
> index bd537438c793..d58575f8f25f 100644
> --- a/drivers/clk/qcom/gdsc.h
> +++ b/drivers/clk/qcom/gdsc.h
> @@ -57,6 +57,11 @@ struct gdsc {
>
> const char *supply;
> struct regulator *rsupply;
> +
> + const char *domain;
> + unsigned int perf_idx;
> + struct device *pd_dev;
> + int pd_opp;
Please document these fields.
> };
