Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / iio / adc / at91_adc.txt

diff --git a/kernel/Documentation/devicetree/bindings/iio/adc/at91_adc.txt b/kernel/Documentation/devicetree/bindings/iio/adc/at91_adc.txt
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+* AT91's Analog to Digital Converter (ADC)
+
+Required properties:
+  - compatible: Should be "atmel,<chip>-adc"
+    <chip> can be "at91sam9260", "at91sam9g45" or "at91sam9x5"
+  - reg: Should contain ADC registers location and length
+  - interrupts: Should contain the IRQ line for the ADC
+  - clock-names: tuple listing input clock names.
+       Required elements: "adc_clk", "adc_op_clk".
+  - clocks: phandles to input clocks.
+  - atmel,adc-channels-used: Bitmask of the channels muxed and enabled for this
+    device
+  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
+    defined in the datasheet
+  - atmel,adc-vref: Reference voltage in millivolts for the conversions
+  - atmel,adc-res: List of resolutions in bits supported by the ADC. List size
+                  must be two at least.
+  - atmel,adc-res-names: Contains one identifier string for each resolution
+                        in atmel,adc-res property. "lowres" and "highres"
+                        identifiers are required.
+
+Optional properties:
+  - atmel,adc-use-external-triggers: Boolean to enable the external triggers
+  - atmel,adc-use-res: String corresponding to an identifier from
+                      atmel,adc-res-names property. If not specified, the highest
+                      resolution will be used.
+  - atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion
+  - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
+  - atmel,adc-ts-wires: Number of touchscreen wires. Should be 4 or 5. If this
+                        value is set, then the adc driver will enable touchscreen
+                        support.
+    NOTE: when adc touchscreen is enabled, the adc hardware trigger will be
+          disabled. Since touchscreen will occupy the trigger register.
+  - atmel,adc-ts-pressure-threshold: a pressure threshold for touchscreen. It
+                                     makes touch detection more precise.
+
+Optional trigger Nodes:
+  - Required properties:
+    * trigger-name: Name of the trigger exposed to the user
+    * trigger-value: Value to put in the Trigger register
+      to activate this trigger
+  - Optional properties:
+    * trigger-external: Is the trigger an external trigger?
+
+Examples:
+adc0: adc@fffb0000 {
+       #address-cells = <1>;
+       #size-cells = <0>;
+       compatible = "atmel,at91sam9260-adc";
+       reg = <0xfffb0000 0x100>;
+       interrupts = <20 IRQ_TYPE_LEVEL_HIGH 0>;
+       clocks = <&adc_clk>, <&adc_op_clk>;
+       clock-names = "adc_clk", "adc_op_clk";
+       atmel,adc-channels-used = <0xff>;
+       atmel,adc-startup-time = <40>;
+       atmel,adc-use-external-triggers;
+       atmel,adc-vref = <3300>;
+       atmel,adc-res = <8 10>;
+       atmel,adc-res-names = "lowres", "highres";
+       atmel,adc-use-res = "lowres";
+
+       trigger@0 {
+               reg = <0>;
+               trigger-name = "external-rising";
+               trigger-value = <0x1>;
+               trigger-external;
+       };
+       trigger@1 {
+               reg = <1>;
+               trigger-name = "external-falling";
+               trigger-value = <0x2>;
+               trigger-external;
+       };
+
+       trigger@2 {
+               reg = <2>;
+               trigger-name = "external-any";
+               trigger-value = <0x3>;
+               trigger-external;
+       };
+
+       trigger@3 {
+               reg = <3>;
+               trigger-name = "continuous";
+               trigger-value = <0x6>;
+       };
+};