summaryrefslogtreecommitdiffstats
path: root/dts/Bindings/iio/adc/qcom,spmi-vadc.txt
diff options
context:
space:
mode:
Diffstat (limited to 'dts/Bindings/iio/adc/qcom,spmi-vadc.txt')
-rw-r--r--dts/Bindings/iio/adc/qcom,spmi-vadc.txt81
1 files changed, 60 insertions, 21 deletions
diff --git a/dts/Bindings/iio/adc/qcom,spmi-vadc.txt b/dts/Bindings/iio/adc/qcom,spmi-vadc.txt
index 0fb46137f9..b3c86f4ac7 100644
--- a/dts/Bindings/iio/adc/qcom,spmi-vadc.txt
+++ b/dts/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>;