Re: [PATCH v2 01/10] regulator: s5m8767: do not use reset value as DVS voltage if GPIO DVS is disabled

[Rob Herring]

On Fri, 01 Oct 2021 11:40:57 +0200, Krzysztof Kozlowski wrote:
> The driver and its bindings, before commit 04f9f068a619 ("regulator:
> s5m8767: Modify parsing method of the voltage table of buck2/3/4") were
> requiring to provide at least one safe/default voltage for DVS registers
> if DVS GPIO is not being enabled.
> 
> IOW, if s5m8767,pmic-buck2-uses-gpio-dvs is missing, the
> s5m8767,pmic-buck2-dvs-voltage should still be present and contain one
> voltage.
> 
> This requirement was coming from driver behavior matching this condition
> (none of DVS GPIO is enabled): it was always initializing the DVS
> selector pins to 0 and keeping the DVS enable setting at reset value
> (enabled).  Therefore if none of DVS GPIO is enabled in devicetree,
> driver was configuring the first DVS voltage for buck[234].
> 
> Mentioned commit 04f9f068a619 ("regulator: s5m8767: Modify parsing
> method of the voltage table of buck2/3/4") broke it because DVS voltage
> won't be parsed from devicetree if DVS GPIO is not enabled.  After the
> change, driver will configure bucks to use the register reset value as
> voltage which might have unpleasant effects.
> 
> Fix this by relaxing the bindings constrain: if DVS GPIO is not enabled
> in devicetree (therefore DVS voltage is also not parsed), explicitly
> disable it.
> 
> Cc: <stable@xxxxxxxxxxxxxxx>
> Fixes: 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4")
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
> ---
>  .../bindings/regulator/samsung,s5m8767.txt    | 21 +++++++------------
>  drivers/regulator/s5m8767.c                   | 21 ++++++++-----------
>  2 files changed, 17 insertions(+), 25 deletions(-)
> 

Acked-by: Rob Herring <robh@xxxxxxxxxx>