[PATCH v2 3/9] devicetree: bindings: Document qcom,saw2 node

Mark Rutland mark.rutland at arm.com
Wed Jan 8 09:36:26 EST 2014


On Tue, Dec 24, 2013 at 12:39:47AM +0000, Stephen Boyd wrote:
> The saw2 binding describes the SPM/AVS wrapper hardware used to
> control the regulator supplying voltage to the Krait CPUs.
> 
> Cc: <devicetree at vger.kernel.org>
> Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
> ---
>  .../devicetree/bindings/arm/msm/qcom,saw2.txt      | 35 ++++++++++++++++++++++
>  1 file changed, 35 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt
> 
> diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt b/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt
> new file mode 100644
> index 0000000..1505fb8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt
> @@ -0,0 +1,35 @@
> +SPM AVS Wrapper 2 (SAW2)
> +
> +The SAW2 is a wrapper around the Subsystem Power Manager (SPM) and the
> +Adaptive Voltage Scaling (AVS) hardware. The SPM is a programmable
> +micro-controller that transitions a piece of hardware (like a processor or
> +subsystem) into and out of low power modes via a direct connection to
> +the PMIC. It can also be wired up to interact with other processors in the
> +system, notifying them when a low power state is entered or exited.
> +
> +PROPERTIES
> +
> +- compatible:
> +	Usage: required
> +	Value type: <string>
> +	Definition: shall contain "qcom,saw2". A more specific value should be
> +		    one of:
> +			 "qcom,saw2-v1"
> +			 "qcom,saw2-v1.1"
> +			 "qcom,saw2-v2"
> +			 "qcom,saw2-v2.1"
> +
> +- reg:
> +	Usage: required
> +	Value type: <prop-encoded-array>
> +	Definition: the first element specifies the base address and size of
> +		    the register region. An optional second element specifies
> +		    the base address and size of the alias register region.
> +
> +
> +Example:
> +
> +	regulator at 2099000 {
> +		compatible = "qcom,saw2";
> +		reg = <0x02099000 0x1000>, <0x02009000 0x1000>;
> +	};

I have the same general worry as with the ACC regarding the implicit
relationship between CPUs and the registers controlling them, but I
assume that's fine for current implementations, and the binding's so
simple there's nothing preventing future extension.

Acked-By: Mark Rutland <mark.rutland at arm.com>

Thanks,
Mark.



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