On 18/03/2022 21:50, Robin Murphy wrote: > On 2022-02-25 21:13, Heiner Kallweit wrote: >> Add a YAML schema binding for TM1628 auxdisplay >> (7/11-segment LED) controller. >> >> This patch is partially based on previous work from >> Andreas Färber <afaerber@xxxxxxx>. >> >> Co-developed-by: Andreas Färber <afaerber@xxxxxxx> >> Signed-off-by: Andreas Färber <afaerber@xxxxxxx> >> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> >> --- >> v5: >> - add vendor prefix to driver-specific properties >> --- >> .../bindings/auxdisplay/titanmec,tm1628.yaml | 92 +++++++++++++++++++ >> 1 file changed, 92 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/auxdisplay/titanmec,tm1628.yaml >> >> diff --git a/Documentation/devicetree/bindings/auxdisplay/titanmec,tm1628.yaml b/Documentation/devicetree/bindings/auxdisplay/titanmec,tm1628.yaml >> new file mode 100644 >> index 000000000..2a1ef692c >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/auxdisplay/titanmec,tm1628.yaml >> @@ -0,0 +1,92 @@ >> +# SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/auxdisplay/titanmec,tm1628.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: Titan Micro Electronics TM1628 LED controller >> + >> +maintainers: >> + - Andreas Färber <afaerber@xxxxxxx> >> + - Heiner Kallweit <hkallweit1@xxxxxxxxx> >> + >> +allOf: >> + - $ref: /schemas/spi/spi-peripheral-props.yaml# >> + >> +properties: >> + compatible: >> + const: titanmec,tm1628 >> + >> + reg: >> + maxItems: 1 >> + >> + titanmec,grid: >> + description: >> + Mapping of display digit position to grid number. >> + This implicitly defines the display size. >> + $ref: /schemas/types.yaml#/definitions/uint8-array >> + minItems: 1 >> + maxItems: 7 >> + >> + titanmec,segment-mapping: >> + description: >> + Mapping of 7 segment display segments A-G to bit numbers 1-12. >> + $ref: /schemas/types.yaml#/definitions/uint8-array >> + minItems: 7 >> + maxItems: 7 >> + >> + "#address-cells": >> + const: 2 >> + >> + "#size-cells": >> + const: 0 >> + >> +required: >> + - compatible >> + - reg > > Would it be fair to say that "spi-lsb-first" and "spi-3wire" are also > required? The chips aren't configurable so won't exactly be usable any > other way. Furthermore I believe the transmission format actually works > out equivalent to SPI mode 3, so should warrant "spi-cpha" and > "spi-cpol" as well. > >> + >> +patternProperties: >> + "^.*@[1-7],([1-9]|1[0-6])$": >> + type: object >> + $ref: /schemas/leds/common.yaml# >> + unevaluatedProperties: false >> + description: | >> + Properties for a single LED. >> + >> + properties: >> + reg: >> + description: | >> + 1-based grid number, followed by 1-based segment bit number. >> + maxItems: 1 >> + >> + required: >> + - reg > > I'm concerned that this leaves us no room to support the additional > keypad functionality in future. Having now double-checked a datasheet, > the inputs are also a two-dimensional mux (sharing the segment lines), > so the device effectively has two distinct but numerically-overlapping > child address spaces - one addressed by (grid,segment) and the other by > (segment,key). > > Rob, Krysztof, any thoughts on the best DT idiom to leave accommodation > for that? I'm thinking either require an intermediate node to contain > each notional address space, or perhaps add another leading address cell > to select between them? I don't believe any of these things have further > functionality beyond that. I think intermediate nodes - leds, keys - are more appropriate, because it is self-describing. Additional address space number would require decoding this "0" or "1" into LED/key. For complex devices - like PMICs with regulators, RTC and clocks - we already have such patterns. Best regards, Best regards, Krzysztof
