diff options
Diffstat (limited to 'Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt | 81 |
1 files changed, 60 insertions, 21 deletions
diff --git a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt index 0fb46137f936..b3c86f4ac7cd 100644 --- a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt +++ b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt @@ -1,7 +1,9 @@ -Qualcomm's SPMI PMIC voltage ADC +Qualcomm's SPMI PMIC ADC -SPMI PMIC voltage ADC (VADC) provides interface to clients to read -voltage. The VADC is a 15-bit sigma-delta ADC. +- SPMI PMIC voltage ADC (VADC) provides interface to clients to read + voltage. The VADC is a 15-bit sigma-delta ADC. +- SPMI PMIC5 voltage ADC (ADC) provides interface to clients to read + voltage. The VADC is a 16-bit sigma-delta ADC. VADC node: @@ -9,11 +11,13 @@ VADC node: Usage: required Value type: <string> Definition: Should contain "qcom,spmi-vadc". + Should contain "qcom,spmi-adc5" for PMIC5 ADC driver. + Should contain "qcom,spmi-adc-rev2" for PMIC rev2 ADC driver. - reg: Usage: required Value type: <prop-encoded-array> - Definition: VADC base address and length in the SPMI PMIC register map. + Definition: VADC base address in the SPMI PMIC register map. - #address-cells: Usage: required @@ -45,13 +49,26 @@ Channel node properties: Definition: ADC channel number. See include/dt-bindings/iio/qcom,spmi-vadc.h +- label: + Usage: required for "qcom,spmi-adc5" and "qcom,spmi-adc-rev2" + Value type: <empty> + Definition: ADC input of the platform as seen in the schematics. + For thermistor inputs connected to generic AMUX or GPIO inputs + these can vary across platform for the same pins. Hence select + the platform schematics name for this channel. + - qcom,decimation: Usage: optional Value type: <u32> Definition: This parameter is used to decrease ADC sampling rate. Quicker measurements can be made by reducing decimation ratio. - Valid values are 512, 1024, 2048, 4096. - If property is not found, default value of 512 will be used. + - For compatible property "qcom,spmi-vadc", valid values are + 512, 1024, 2048, 4096. If property is not found, default value + of 512 will be used. + - For compatible property "qcom,spmi-adc5", valid values are 250, 420 + and 840. If property is not found, default value of 840 is used. + - For compatible property "qcom,spmi-adc-rev2", valid values are 256, + 512 and 1024. If property is not present, default value is 1024. - qcom,pre-scaling: Usage: optional @@ -66,21 +83,38 @@ Channel node properties: - qcom,ratiometric: Usage: optional Value type: <empty> - Definition: Channel calibration type. If this property is specified - VADC will use the VDD reference (1.8V) and GND for channel - calibration. If property is not found, channel will be - calibrated with 0.625V and 1.25V reference channels, also - known as absolute calibration. + Definition: Channel calibration type. + - For compatible property "qcom,spmi-vadc", if this property is + specified VADC will use the VDD reference (1.8V) and GND for + channel calibration. If property is not found, channel will be + calibrated with 0.625V and 1.25V reference channels, also + known as absolute calibration. + - For compatible property "qcom,spmi-adc5" and "qcom,spmi-adc-rev2", + if this property is specified VADC will use the VDD reference + (1.875V) and GND for channel calibration. If property is not found, + channel will be calibrated with 0V and 1.25V reference channels, + also known as absolute calibration. - qcom,hw-settle-time: Usage: optional Value type: <u32> Definition: Time between AMUX getting configured and the ADC starting - conversion. Delay = 100us * (value) for value < 11, and - 2ms * (value - 10) otherwise. - Valid values are: 0, 100, 200, 300, 400, 500, 600, 700, 800, - 900 us and 1, 2, 4, 6, 8, 10 ms - If property is not found, channel will use 0us. + conversion. The 'hw_settle_time' is an index used from valid values + and programmed in hardware to achieve the hardware settling delay. + - For compatible property "qcom,spmi-vadc" and "qcom,spmi-adc-rev2", + Delay = 100us * (hw_settle_time) for hw_settle_time < 11, + and 2ms * (hw_settle_time - 10) otherwise. + Valid values are: 0, 100, 200, 300, 400, 500, 600, 700, 800, + 900 us and 1, 2, 4, 6, 8, 10 ms. + If property is not found, channel will use 0us. + - For compatible property "qcom,spmi-adc5", delay = 15us for + value 0, 100us * (value) for values < 11, + and 2ms * (value - 10) otherwise. + Valid values are: 15, 100, 200, 300, 400, 500, 600, 700, 800, + 900 us and 1, 2, 4, 6, 8, 10 ms + Certain controller digital versions have valid values of + 15, 100, 200, 300, 400, 500, 600, 700, 1, 2, 4, 8, 16, 32, 64, 128 ms + If property is not found, channel will use 15us. - qcom,avg-samples: Usage: optional @@ -89,13 +123,18 @@ Channel node properties: Averaging provides the option to obtain a single measurement from the ADC that is an average of multiple samples. The value selected is 2^(value). - Valid values are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512 - If property is not found, 1 sample will be used. + - For compatible property "qcom,spmi-vadc", valid values + are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512 + If property is not found, 1 sample will be used. + - For compatible property "qcom,spmi-adc5" and "qcom,spmi-adc-rev2", + valid values are: 1, 2, 4, 8, 16 + If property is not found, 1 sample will be used. NOTE: -Following channels, also known as reference point channels, are used for -result calibration and their channel configuration nodes should be defined: +For compatible property "qcom,spmi-vadc" following channels, also known as +reference point channels, are used for result calibration and their channel +configuration nodes should be defined: VADC_REF_625MV and/or VADC_SPARE1(based on PMIC version) VADC_REF_1250MV, VADC_GND_REF and VADC_VDD_VADC. @@ -104,7 +143,7 @@ Example: /* VADC node */ pmic_vadc: vadc@3100 { compatible = "qcom,spmi-vadc"; - reg = <0x3100 0x100>; + reg = <0x3100>; interrupts = <0x0 0x31 0x0 IRQ_TYPE_EDGE_RISING>; #address-cells = <1>; #size-cells = <0>; |