This adds the binding document describing the three hardware blocks related to the Light Pulse Generator found in a wide range of Qualcomm PMICs.
Signed-off-by: Bjorn Andersson <[email protected]> --- Changes since v1: - Dropped custom pattern properties - Renamed cell-index to qcom,lpg-channel to clarify its purpose .../devicetree/bindings/leds/leds-qcom-lpg.txt | 145 +++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/leds-qcom-lpg.txt diff --git a/Documentation/devicetree/bindings/leds/leds-qcom-lpg.txt b/Documentation/devicetree/bindings/leds/leds-qcom-lpg.txt new file mode 100644 index 000000000000..cc9ffee6586b --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-qcom-lpg.txt @@ -0,0 +1,145 @@ +Binding for Qualcomm Light Pulse Generator + +The Qualcomm Light Pulse Generator consists of three different hardware blocks; +a ramp generator with lookup table, the light pulse generator and a three +channel current sink. These blocks are found in a wide range of Qualcomm PMICs. +Each of these are described individually below. + += Lookup Table (LUT) + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,spmi-lpg-lut" + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: base address of the LUT block + +- qcom,lut-size: + Usage: required + Value type: <u32> + Definition: number of elements available in the lookup table + += Light Pulse Generator (LPG) +The Light Pulse Generator can operate either as a standard PWM controller or in +a more advanced lookup-table based mode. These are described separately below. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,spmi-lpg" + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: base address of the LPG block + +== PWM mode + +- #pwm-cells: + Usage: required + Value type: <u32> + Definition: must be 1 + +== Lookup-table mode + +- qcom,lpg-channel: + Usage: required, when referencing a LUT + Value type: <u32> + Definition: identifier of the LPG channel, used to associate the LPG + with a particular ramp generator in the LUT block + +- default-state: + Usage: optional + Value type: <string> + Definition: default state, as defined in common.txt + +- label: + Usage: optional + Value type: <string> + Definition: label of the LED, as defined in common.txt + +- linux,default-trigger: + Usage: optional + Value type: <string> + Definition: default trigger, as defined in common.txt + +- qcom,tri-led: + Usage: optional + Value type: <prop-encoded-array> + Definition: a phandle of a TRILED node and a single u32 denoting which + output channel to control + +- qcom,lut: + Usage: optional + Value type: <prop-encoded-array> + Definition: phandle of a LUT node + +- qcom,dtest: + Usage: optional + Value type: <prop-encoded-array> + Definition: configures the output into an internal test line of the + pmic. A first u32 defines which test line to use and the + second cell configures how the value should be outputed + (available lines and configuration differs between PMICs) + += LED Current Sink (TRILED) + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,spmi-tri-led" + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: base address of the TRILED block + +- qcom,power-source: + Usage: required + Value type: <u32> + Definition: power-source used to drive the output, as defined in the + datasheet + += EXAMPLE: +The following example defines a single output of the PMI8994, sinking current +into a LED. + +&spmi_bus { + pmic@3 { + compatible = "qcom,pmi8994", "qcom,spmi-pmic"; + reg = <0x3 SPMI_USID>; + #address-cells = <1>; + #size-cells = <0>; + + pmi8994_lpg_lut: lpg-lut@b000 { + compatible = "qcom,spmi-lpg-lut"; + reg = <0xb000>; + + qcom,lut-size = <24>; + }; + + lpg@b200 { + compatible = "qcom,spmi-lpg"; + reg = <0xb200>; + + cell-index = <2>; + + label = "lpg:green:user0"; + + qcom,tri-led = <&pmi8994_tri_led 1>; + qcom,lut = <&pmi8994_lpg_lut>; + + default-state = "on"; + }; + + pmi8994_tri_led: tri-led@d000 { + compatible = "qcom,spmi-tri-led"; + reg = <0xd000>; + + qcom,power-source = <1>; + }; + }; +}; -- 2.12.0
