Re: [PATCH v2] clk: qcom: gdsc: Ensure regulator init state matches GDSC state

From: Stephen Boyd
Date: Thu Aug 05 2021 - 21:21:39 EST


Quoting Bjorn Andersson (2021-07-21 15:40:56)
> As GDSCs are registered and found to be already enabled gdsc_init()
> ensures that 1) the kernel state matches the hardware state, and 2)
> votable GDSCs are properly enabled from this master as well.
>
> But as the (optional) supply regulator is enabled deep into
> gdsc_toggle_logic(), which is only executed for votable GDSCs the
> kernel's state of the regulator might not match the hardware. The
> regulator might be automatically turned off if no other users are
> present or the next call to gdsc_disable() would cause an unbalanced
> regulator_disable().
>
> But as the votable case deals with an already enabled GDSC, most of
> gdsc_enable() and gdsc_toggle_logic() can be skipped. Reducing it to
> just clearing the SW_COLLAPSE_MASK and enabling hardware control allow
> us to simply call regulator_enable() in both cases.
>
> The enablement of hardware control seems to be an independent property
> from the GDSC being enabled, so this is moved outside that conditional
> segment.
>
> Lastly, as the propagation of ALWAY_ON to GENPD_FLAG_ALWAYS_ON needs to
> happen regardless of the initial state this is grouped together with the
> other sc->pd updates at the end of the function.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 37416e554961 ("clk: qcom: gdsc: Handle GDSC regulator supplies")
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> ---

Applied to clk-fixes