On 28/07/2022 11:17, Martin Zaťovič wrote: > Wiegand write-only driver requires definitions of two GPIO lines > in the devicetree. This adds the documentation of their > definitions. > Subject prefix consistent with subsystem, so: dt-bindings: bus: add Wiegand bus There should be no references to drivers in bindings. Bindings also go before the actual driver in the patchset. > Signed-off-by: Martin Zaťovič <m.zatovic1@xxxxxxxxx> > --- > .../devicetree/bindings/bus/wiegand-gpio.yaml | 66 +++++++++++++++++++ > MAINTAINERS | 1 + > 2 files changed, 67 insertions(+) > create mode 100644 Documentation/devicetree/bindings/bus/wiegand-gpio.yaml > > diff --git a/Documentation/devicetree/bindings/bus/wiegand-gpio.yaml b/Documentation/devicetree/bindings/bus/wiegand-gpio.yaml > new file mode 100644 > index 000000000000..74733aadc61e > --- /dev/null > +++ b/Documentation/devicetree/bindings/bus/wiegand-gpio.yaml > @@ -0,0 +1,66 @@ > +# SPDX-License-Identifier: GPL-2.0-only Dual license please. > + > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/bus/wiegand-gpio.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Wiegand write-only GPIO driver > + > +maintainers: > + - Martin Zaťovič <m.zatovic1@xxxxxxxxx> > + > +description: | > + Wiegand interface is a wiring standard popularized in the 1980s. To this day > + many card readers, fingerprint readers, sensors, etc. use Wiegand interface > + particularly for access control applications. It utilizes two wires to > + transmit the data - D0 and D1. > + > + Both data lines are initially pulled up. To send a bit of value 1, the D1 > + line is set low. Similarly to send a bit of value 0, the D0 line is set low. > + Standard Wiegand formats include 26, 36 and 37 bit and they reserve the first > + and last bits for parity. The first(MSB) parity bit is set to 1 if the parity > + of the first half of the payload is odd. The last(LSB) parity bit is set to 1 > + if the parity of the second half of the payload even. > + > +properties: > + $nodename: > + pattern: "^wiegand-gpio(@[0-9a-f]+)?$" > + > + compatible: > + contains: Nope. See example-schema. > + const: gpio,wiegand-gpio > + description: > + Shall contain "wiegand-gpio" for the driver to match with this node. No description. See example-schema. > + > + wiegand-data-hi-gpios: I propose just data-hi-gpios > + description: > + gpio used to transmit bits the value of which is 1, it should be > + flagged as active high with GPIO_ACTIVE_HIGH from > + <dt-bindings/gpio/gpio.h>. > + maxItems: 1 > + > + wiegand-data-lo-gpios: data-lo-gpios > + description: > + gpio used to transmit bits the value of which is 1, it should be > + flagged as active high with GPIO_ACTIVE_HIGH from > + <dt-bindings/gpio/gpio.h>. > + maxItems: 1 > + > +required: > + - compatible > + - wiegand-data-hi-gpios > + - wiegand-data-lo-gpios > + > +additionalProperties: true Nope. This must be false, unless you create here a bus bindings. But in such case you example is incomplete. > + > +examples: > + - | > + wiegand-gpio { Just wiegand. https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation > + compatible = "wiegand-gpio"; > + pinctrl-names = "default"; > + pinctrl-0 = <&pinctrl_uart1_wiegand>; > + wiegand-data-hi-gpios = <&gpio2 1 GPIO_ACTIVE_HIGH>; > + wiegand-data-lo-gpios = <&gpio2 2 GPIO_ACTIVE_HIGH>; > + status = "okay"; No need for status. > + }; > diff --git a/MAINTAINERS b/MAINTAINERS > index 9a519530e44e..c7db1e41cc02 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -21589,6 +21589,7 @@ F: drivers/rtc/rtc-sd3078.c > WIEGAND WRITE-ONLY GPIO DRIVER > M: Martin Zaťovič <m.zatovic1@xxxxxxxxx> > S: Maintained > +F: Documentation/devicetree/bindings/bus/wiegand-gpio.yaml > F: drivers/bus/wiegand-gpio.c > F: drivers/bus/wiegand-gpio.h > Best regards, Krzysztof
