diff options
Diffstat (limited to 'Documentation/devicetree/bindings/input')
| -rw-r--r-- | Documentation/devicetree/bindings/input/touchscreen/ti,am3359-tsc.yaml | 76 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt | 91 |
2 files changed, 76 insertions, 91 deletions
diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti,am3359-tsc.yaml b/Documentation/devicetree/bindings/input/touchscreen/ti,am3359-tsc.yaml new file mode 100644 index 000000000000..e44cc65abc8c --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/ti,am3359-tsc.yaml @@ -0,0 +1,76 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/input/touchscreen/ti,am3359-tsc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: TI AM3359 Touchscreen controller + +maintainers: + - Miquel Raynal <miquel.raynal@bootlin.com> + +properties: + compatible: + const: ti,am3359-tsc + + ti,wires: + description: Wires refer to application modes i.e. 4/5/8 wire touchscreen + support on the platform. + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [4, 5, 8] + + ti,x-plate-resistance: + description: X plate resistance + $ref: /schemas/types.yaml#/definitions/uint32 + + ti,coordinate-readouts: + description: The sequencer supports a total of 16 programmable steps. Each + step is used to read a single coordinate. A single readout is enough but + multiple reads can increase the quality. A value of 5 means, 5 reads for + X, 5 for Y and 2 for Z (always). This utilises 12 of the 16 software steps + available. The remaining 4 can be used by the ADC. + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 1 + maximum: 6 + + ti,wire-config: + description: Different boards could have a different order for connecting + wires on touchscreen. We need to provide an 8-bit number where the + first four bits represent the analog lines and the next 4 bits represent + positive/negative terminal on that input line. Notations to represent the + input lines and terminals respectively are as follows, AIN0 = 0, AIN1 = 1 + and so on until AIN7 = 7. XP = 0, XN = 1, YP = 2, YN = 3. + $ref: /schemas/types.yaml#/definitions/uint32-array + minItems: 4 + maxItems: 8 + + ti,charge-delay: + description: Length of touch screen charge delay step in terms of ADC clock + cycles. Charge delay value should be large in order to avoid false pen-up + events. This value effects the overall sampling speed, hence need to be + kept as low as possible, while avoiding false pen-up event. Start from a + lower value, say 0x400, and increase value until false pen-up events are + avoided. The pen-up detection happens immediately after the charge step, + so this does in fact function as a hardware knob for adjusting the amount + of "settling time". + $ref: /schemas/types.yaml#/definitions/uint32 + +required: + - compatible + - ti,wires + - ti,x-plate-resistance + - ti,coordinate-readouts + - ti,wire-config + +additionalProperties: false + +examples: + - | + tsc { + compatible = "ti,am3359-tsc"; + ti,wires = <4>; + ti,x-plate-resistance = <200>; + ti,coordinate-readouts = <5>; + ti,wire-config = <0x00 0x11 0x22 0x33>; + ti,charge-delay = <0x400>; + }; diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt deleted file mode 100644 index aad5e34965eb..000000000000 --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt +++ /dev/null @@ -1,91 +0,0 @@ -* TI - TSC ADC (Touschscreen and analog digital converter) -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -Required properties: -- mfd - compatible: Should be - "ti,am3359-tscadc" for AM335x/AM437x SoCs - "ti,am654-tscadc", "ti,am3359-tscadc" for AM654 SoCs -- child "tsc" - compatible: Should be "ti,am3359-tsc". - ti,wires: Wires refer to application modes i.e. 4/5/8 wire touchscreen - support on the platform. - ti,x-plate-resistance: X plate resistance - ti,coordinate-readouts: The sequencer supports a total of 16 - programmable steps each step is used to - read a single coordinate. A single - readout is enough but multiple reads can - increase the quality. - A value of 5 means, 5 reads for X, 5 for - Y and 2 for Z (always). This utilises 12 - of the 16 software steps available. The - remaining 4 can be used by the ADC. - ti,wire-config: Different boards could have a different order for - connecting wires on touchscreen. We need to provide an - 8 bit number where in the 1st four bits represent the - analog lines and the next 4 bits represent positive/ - negative terminal on that input line. Notations to - represent the input lines and terminals resoectively - is as follows: - AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7. - XP = 0, XN = 1, YP = 2, YN = 3. -- child "adc" - compatible: Should be - "ti,am3359-adc" for AM335x/AM437x SoCs - "ti,am654-adc", "ti,am3359-adc" for AM654 SoCs - ti,adc-channels: List of analog inputs available for ADC. - AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7. - -Optional properties: -- child "tsc" - ti,charge-delay: Length of touch screen charge delay step in terms of - ADC clock cycles. Charge delay value should be large - in order to avoid false pen-up events. This value - effects the overall sampling speed, hence need to be - kept as low as possible, while avoiding false pen-up - event. Start from a lower value, say 0x400, and - increase value until false pen-up events are avoided. - The pen-up detection happens immediately after the - charge step, so this does in fact function as a - hardware knob for adjusting the amount of "settling - time". - -- child "adc" - ti,chan-step-opendelay: List of open delays for each channel of - ADC in the order of ti,adc-channels. The - value corresponds to the number of ADC - clock cycles to wait after applying the - step configuration registers and before - sending the start of ADC conversion. - Maximum value is 0x3FFFF. - ti,chan-step-sampledelay: List of sample delays for each channel - of ADC in the order of ti,adc-channels. - The value corresponds to the number of - ADC clock cycles to sample (to hold - start of conversion high). - Maximum value is 0xFF. - ti,chan-step-avg: Number of averages to be performed for each - channel of ADC. If average is 16 then input - is sampled 16 times and averaged to get more - accurate value. This increases the time taken - by ADC to generate a sample. Valid range is 0 - average to 16 averages. Maximum value is 16. - -Example: - tscadc: tscadc@44e0d000 { - compatible = "ti,am3359-tscadc"; - tsc { - ti,wires = <4>; - ti,x-plate-resistance = <200>; - ti,coordiante-readouts = <5>; - ti,wire-config = <0x00 0x11 0x22 0x33>; - ti,charge-delay = <0x400>; - }; - - adc { - ti,adc-channels = <4 5 6 7>; - ti,chan-step-opendelay = <0x098 0x3ffff 0x098 0x0>; - ti,chan-step-sampledelay = <0xff 0x0 0xf 0x0>; - ti,chan-step-avg = <16 2 4 8>; - }; - } |