On Wed, Feb 26, 2025 at 03:19:14PM +0100, Maud Spierings wrote: > Add the bindings that describe a GOcontroll Moduline module slot. This > slot provides all the interfaces to interface with a Moduline compatible > IO module. The actual module is not reasonable to describe as it can be > swapped at will, with this connector the driver will be able to probe > for a module on boot. > > The connector consists of 2 parts, one part for interfacing with the SoC > and main board, the other part has 13 IO channels for the module to > interact with the outside world. The functions of these IO channels are > determined by the type of module in the slot. The IO on the SoC side is > as follows: > > - a 3v3 supply, this tends to be the logic level of the module and its > microcontroller > - a 5v0 supply, this can be used to power low power peripherals on the > module > - a 6v-8v supply, this can be used for high power peripherals on the > module > - a 6v-30v supply, this tends to be a dirty supply that comes from the > controller supply after some circuit protection, or is the same as > the 6v-8v supply. > - an SPI bus which carries the communication between the SoC and the > microcontroller on the module. > - an I2C bus shared between the SoC and all module slots which can > carry direct module-to-module communication. > - a reset line > - an interrupt line that indicates a clear to transmit signal > - a sync line shared between the SoC and all module slots which could > be used to synchronize modules for time sensitive IO spread across > modules. > - a SMBus alert line that is shared between the modules but is not > connected to the SoC so that is ignored. > > A slot-number property is used to identify the physical location of a > module slot. Without it, it would be impossible to identify which module > to control if there are multiple of one type, to address the desired IO. Is that for a person to identify slots or s/w? If just a person, we generally use 'label' as in a sticker on the connector. If s/w, we generally try to avoid made up indexing in DT though there are some exceptions. > > Signed-off-by: Maud Spierings <maudspierings@xxxxxxxxxxxxxx> > --- > .../connector/gocontroll,moduline-module-slot.yaml | 88 ++++++++++++++++++++++ > 1 file changed, 88 insertions(+) > > diff --git a/Documentation/devicetree/bindings/connector/gocontroll,moduline-module-slot.yaml b/Documentation/devicetree/bindings/connector/gocontroll,moduline-module-slot.yaml > new file mode 100644 > index 0000000000000000000000000000000000000000..a16ae2762d160180d5b163e20f5294235e65053b > --- /dev/null > +++ b/Documentation/devicetree/bindings/connector/gocontroll,moduline-module-slot.yaml > @@ -0,0 +1,88 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/connector/gocontroll,moduline-module-slot.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: GOcontroll Moduline Module slot > + > +maintainers: > + - Maud Spierings <maudspierings@xxxxxxxxxxxxxx> > + > +description: > + The GOcontroll Moduline module slot represents a connector that fullfills the > + Moduline slot specification, and can thus house any IO module that is also > + built to this spec. > + > +properties: > + compatible: > + const: gocontroll,moduline-module-slot > + > + reg: > + maxItems: 1 > + > + interrupts: > + description: indicates readiness, high means busy. > + maxItems: 1 > + reset-gpios: > + description: resets the module, active low. > + maxItems: 1 > + sync-gpios: > + description: sync line between all module slots. > + maxItems: 1 > + > + vdd-supply: > + description: low power 3v3 supply generally for the microcontroller. > + vddp-supply: > + description: medium power 5v0 supply for on module low power peripherals. > + vddhpp-supply: > + description: high power 6v-8v supply for on module high power peripherals. > + power-supply: > + description: high power 6v-30v supply for high power module circuits. > + > + i2c-bus: > + description: i2c bus shared between module slots and the SoC > + $ref: /schemas/types.yaml#/definitions/phandle > + > + slot-number: > + description: > + The number of the module slot representing the location of on the pcb. > + This enables access to the modules based on slot location. > + $ref: /schemas/types.yaml#/definitions/uint32 > + > + spi-max-frequency: true > + > +required: > + - compatible > + - reg > + - reset-gpios > + - interrupts > + - sync-gpios > + - i2c-bus > + - slot-number > + > +additionalProperties: false > + > +examples: > + - | > + #include <dt-bindings/gpio/gpio.h> > + #include <dt-bindings/interrupt-controller/irq.h> > + > + spi { > + #address-cells = <1>; > + #size-cells = <0>; > + > + connector@0 { I find this being a SPI device a bit strange. Is there a defined SPI device that every slot is going to have? Or the connector has SPI interface and *anything* could be attached on it? > + reg = <0>; > + compatible = "gocontroll,moduline-module-slot"; > + reset-gpios = <&gpio5 10 GPIO_ACTIVE_LOW>; > + sync-gpios = <&gpio4 16 GPIO_ACTIVE_HIGH>; > + interrupt-parent = <&gpio4>; > + interrupts = <5 IRQ_TYPE_EDGE_FALLING>; > + vdd-supply = <®_3v3_per>; > + vddp-supply = <®_5v0>; > + vddhpp-supply = <®_6v4>; > + i2c-bus = <&i2c2>; > + slot-number = <1>; > + }; > + }; > > -- > 2.48.1 >