On Sat, 28 Nov 2020 23:28:12 +0100
Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> wrote:
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> There are a few things we would do differently in an ADC binding if we
> were starting from scratch but we are stuck with what we have (which
> made sense back when this was written!)
>
> We may be able to tighten up some elements of this binding in the future
> by careful checking of what values properties can actually take.
>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
> Cc: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
> [Alexandre Belloni: add sama5d3, remove atmel,adc-res and atmel,adc-res-names]
> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> Reviewed-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
So this one is interesting from the question of what the right tag chain is.
I've signed-off on it again whilst applying but also added a note to make
it clear the two sign offs are actually for different things.
Jonathan
> ---
> .../devicetree/bindings/iio/adc/at91_adc.txt | 78 --------
> .../bindings/iio/adc/atmel,sama9260-adc.yaml | 167 ++++++++++++++++++
> 2 files changed, 167 insertions(+), 78 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/iio/adc/at91_adc.txt
> create mode 100644 Documentation/devicetree/bindings/iio/adc/atmel,sama9260-adc.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/at91_adc.txt b/Documentation/devicetree/bindings/iio/adc/at91_adc.txt
> deleted file mode 100644
> index da393ac5c05f..000000000000
> --- a/Documentation/devicetree/bindings/iio/adc/at91_adc.txt
> +++ /dev/null
> @@ -1,78 +0,0 @@
> -* AT91's Analog to Digital Converter (ADC)
> -
> -Required properties:
> - - compatible: Should be "atmel,<chip>-adc"
> - <chip> can be "at91sam9260", "at91sam9g45", "at91sam9x5" or "sama5d3"
> - - 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
> -
> -Optional properties:
> - - atmel,adc-use-external-triggers: Boolean to enable the external triggers
> - - atmel,adc-use-res: String selecting the resolution, can be "lowres" or
> - "highres". 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";
> -
> - trigger0 {
> - trigger-name = "external-rising";
> - trigger-value = <0x1>;
> - trigger-external;
> - };
> - trigger1 {
> - trigger-name = "external-falling";
> - trigger-value = <0x2>;
> - trigger-external;
> - };
> -
> - trigger2 {
> - trigger-name = "external-any";
> - trigger-value = <0x3>;
> - trigger-external;
> - };
> -
> - trigger3 {
> - trigger-name = "continuous";
> - trigger-value = <0x6>;
> - };
> -};
> diff --git a/Documentation/devicetree/bindings/iio/adc/atmel,sama9260-adc.yaml b/Documentation/devicetree/bindings/iio/adc/atmel,sama9260-adc.yaml
> new file mode 100644
> index 000000000000..9b0ff59e75de
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/atmel,sama9260-adc.yaml
> @@ -0,0 +1,167 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/atmel,sama9260-adc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: AT91 sama9260 and similar Analog to Digital Converter (ADC)
> +
> +maintainers:
> + - Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + enum:
> + - atmel,at91sam9260-adc
> + - atmel,at91sam9rl-adc
> + - atmel,at91sam9g45-adc
> + - atmel,at91sam9x5-adc
> + - atmel,at91sama5d3-adc
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + minItems: 2
> + maxItems: 2
> +
> + clock-names:
> + items:
> + - const: adc_clk
> + - const: adc_op_clk
> +
> + atmel,adc-channels-used:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: Bitmask of the channels muxed and enabled for this device
> +
> + atmel,adc-startup-time:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Startup Time of the ADC in microseconds as defined in the datasheet
> +
> + atmel,adc-vref:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: Reference voltage in millivolts for the conversions
> +
> + atmel,adc-use-external-triggers:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description: Enable the external triggers
> +
> + atmel,adc-use-res:
> + $ref: /schemas/types.yaml#/definitions/string
> + description:
> + String corresponding to an identifier from atmel,adc-res-names property.
> + If not specified, the highest resolution will be used.
> + enum:
> + - "lowres"
> + - "highres"
> +
> + atmel,adc-sleep-mode:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description: Enable sleep mode when no conversion
> +
> + atmel,adc-sample-hold-time:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: Sample and Hold Time in microseconds
> +
> + atmel,adc-ts-wires:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: |
> + Number of touchscreen wires. Must be set to enable touchscreen.
> + NOTE: when adc touchscreen is enabled, the adc hardware trigger will be
> + disabled. Since touchscreen will occupy the trigger register.
> + enum:
> + - 4
> + - 5
> +
> + atmel,adc-ts-pressure-threshold:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Pressure threshold for touchscreen.
> +
> + "#io-channel-cells":
> + const: 1
> +
> +additionalProperties: false
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - clock-names
> + - atmel,adc-channels-used
> + - atmel,adc-startup-time
> + - atmel,adc-vref
> +
> +patternProperties:
> + "^(trigger)[0-9]$":
> + type: object
> + description: Child node to describe a trigger exposed to the user.
> + properties:
> + trigger-name:
> + $ref: /schemas/types.yaml#/definitions/string
> + description: Identifying name.
> +
> + trigger-value:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Value to put in the Trigger register to activate this trigger
> +
> + trigger-external:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description: This trigger is provided from an external pin.
> +
> + additionalProperties: false
> + required:
> + - trigger-name
> + - trigger-value
> +
> +examples:
> + - |
> + #include <dt-bindings/dma/at91.h>
> + #include <dt-bindings/interrupt-controller/irq.h>
> + soc {
> + #address-cells = <1>;
> + #size-cells = <1>;
> +
> + adc@fffb0000 {
> + 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-use-res = "lowres";
> +
> + trigger0 {
> + trigger-name = "external-rising";
> + trigger-value = <0x1>;
> + trigger-external;
> + };
> +
> + trigger1 {
> + trigger-name = "external-falling";
> + trigger-value = <0x2>;
> + trigger-external;
> + };
> +
> + trigger2 {
> + trigger-name = "external-any";
> + trigger-value = <0x3>;
> + trigger-external;
> + };
> +
> + trigger3 {
> + trigger-name = "continuous";
> + trigger-value = <0x6>;
> + };
> + };
> + };
> +...
