linux/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
Sahitya Tummala 4cff6d991e ufs: Add freq-table-hz property for UFS device
Add freq-table-hz propery for UFS device to keep track of
<min max> frequencies supported by UFS clocks.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01 13:11:25 +02:00

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* Universal Flash Storage (UFS) Host Controller
UFSHC nodes are defined to describe on-chip UFS host controllers.
Each UFS controller instance should have its own node.
Required properties:
- compatible : compatible list, contains "jedec,ufs-1.1"
- interrupts : <interrupt mapping for UFS host controller IRQ>
- reg : <registers mapping>
Optional properties:
- vdd-hba-supply : phandle to UFS host controller supply regulator node
- vcc-supply : phandle to VCC supply regulator node
- vccq-supply : phandle to VCCQ supply regulator node
- vccq2-supply : phandle to VCCQ2 supply regulator node
- vcc-supply-1p8 : For embedded UFS devices, valid VCC range is 1.7-1.95V
or 2.7-3.6V. This boolean property when set, specifies
to use low voltage range of 1.7-1.95V. Note for external
UFS cards this property is invalid and valid VCC range is
always 2.7-3.6V.
- vcc-max-microamp : specifies max. load that can be drawn from vcc supply
- vccq-max-microamp : specifies max. load that can be drawn from vccq supply
- vccq2-max-microamp : specifies max. load that can be drawn from vccq2 supply
- <name>-fixed-regulator : boolean property specifying that <name>-supply is a fixed regulator
- clocks : List of phandle and clock specifier pairs
- clock-names : List of clock input name strings sorted in the same
order as the clocks property.
- freq-table-hz : Array of <min max> operating frequencies stored in the same
order as the clocks property. If this property is not
defined or a value in the array is "0" then it is assumed
that the frequency is set by the parent clock or a
fixed rate clock source.
Note: If above properties are not defined it can be assumed that the supply
regulators or clocks are always on.
Example:
ufshc@0xfc598000 {
compatible = "jedec,ufs-1.1";
reg = <0xfc598000 0x800>;
interrupts = <0 28 0>;
vdd-hba-supply = <&xxx_reg0>;
vdd-hba-fixed-regulator;
vcc-supply = <&xxx_reg1>;
vcc-supply-1p8;
vccq-supply = <&xxx_reg2>;
vccq2-supply = <&xxx_reg3>;
vcc-max-microamp = 500000;
vccq-max-microamp = 200000;
vccq2-max-microamp = 200000;
clocks = <&core 0>, <&ref 0>, <&iface 0>;
clock-names = "core_clk", "ref_clk", "iface_clk";
freq-table-hz = <100000000 200000000>, <0 0>, <0 0>;
};