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SubjectRe: [PATCH v2 2/9] dt-bindings: phy-qcom-qmp: Add UFS PHY reset
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Quoting Evan Green (2019-01-23 14:11:30)
> Add a required reset to the SDM845 UFS phy to express the PHY reset
> bit inside the UFS controller register space. Before this change, this
> reset was not expressed in the DT, and the driver utilized two different
> callbacks (phy_init and phy_poweron) to implement a two-phase
> initialization procedure that involved deasserting this reset between
> init and poweron. This abused the two callbacks and diluted their
> purpose.
>
> That scheme does not work as regulators cannot be turned off in
> phy_poweroff because they were turned on in init, rather than poweron.
> The net result is that regulators are left on in suspend that shouldn't
> be.
>
> This new scheme gives the UFS reset to the PHY, so that it can fully
> initialize itself in a single callback. We can then turn regulators on
> during poweron and off during poweroff.
>
> Signed-off-by: Evan Green <evgreen@chromium.org>
> Reviewed-by: Rob Herring <robh@kernel.org>
> ---

Reviewed-by: Stephen Boyd <swboyd@chromium.org>

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