Message-ID: <4821b498-ceff-ca61-db94-29839cf5e0be@wirenboard.com>
Date:   Sun, 12 Mar 2023 13:34:50 +0300
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Subject: Re: [PATCHv3 3/4] dt-bindings: wiegand: add GPIO bitbanged Wiegand
 controller
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To:     =?UTF-8?Q?Martin_Za=c5=a5ovi=c4=8d?= <m.zatovic1@gmail.com>,
        linux-kernel@vger.kernel.org
Cc:     robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        gregkh@linuxfoundation.org, airlied@redhat.com, dipenp@nvidia.com,
        treding@nvidia.com, mwen@igalia.com, fmdefrancesco@gmail.com,
        arnd@arndb.de, bvanassche@acm.org, ogabbay@kernel.org,
        axboe@kernel.dk, mathieu.poirier@linaro.org, linux@zary.sk,
        masahiroy@kernel.org, yangyicong@hisilicon.com,
        dan.j.williams@intel.com, jacek.lawrynowicz@linux.intel.com,
        benjamin.tissoires@redhat.com, devicetree@vger.kernel.org,
        furong.zhou@linux.intel.com, andriy.shevchenko@intel.com,
        linus.walleij@linaro.org
References: <20230301142835.19614-1-m.zatovic1@gmail.com>
 <20230301142835.19614-4-m.zatovic1@gmail.com>
From:   Evgeny Boger <boger@wirenboard.com>
Organization: Wiren Board
In-Reply-To: <20230301142835.19614-4-m.zatovic1@gmail.com>
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Precedence: bulk

On 3/1/23 17:28, Martin Zaťovič wrote:
> GPIO bitbanged Wiegand controller requires definitions of GPIO
> lines to be used on top of the common Wiegand properties. Wiegand
> utilizes two such lines - D0(low data line) and D1(high data line).
>
> Acked-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Martin Zaťovič <m.zatovic1@gmail.com>
> ---
>   .../bindings/wiegand/wiegand-gpio.yaml        | 51 +++++++++++++++++++
>   MAINTAINERS                                   |  5 ++
>   2 files changed, 56 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/wiegand/wiegand-gpio.yaml
>
> diff --git a/Documentation/devicetree/bindings/wiegand/wiegand-gpio.yaml b/Documentation/devicetree/bindings/wiegand/wiegand-gpio.yaml
> new file mode 100644
> index 000000000000..df28929f6dae
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/wiegand/wiegand-gpio.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/wiegand/wiegand-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: GPIO bitbanged Wiegand interface devicetree bindings
> +
> +maintainers:
> +  - Martin Zaťovič <m.zatovic1@gmail.com>
> +
> +description:
> +  This represents the GPIO lines used for bit-banged Wiegand on dedicated GPIO
> +  lines.
> +
> +allOf:
> +  - $ref: /schemas/wiegand/wiegand-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: wiegand-gpio
> +
> +  data-hi-gpios:
> +    description: GPIO used as Wiegands data-hi line.
> +    maxItems: 1
> +
> +  data-lo-gpios:
> +    description: GPIO used as Wiegands data-lo line.
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - data-hi-gpios
> +  - data-lo-gpios
In my experience, the data lines are usually labeled D0/D1, sometimes 
DATA0/DATA1. Data high/data low marking is very rare.
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    wiegand@f00 {
> +        compatible = "wiegand-gpio";
> +        pulse-len-us = <50>;
> +        interval-len-us = <2000>;
> +        frame-gap-us = <2000>;
> +        data-lo-gpios = <&gpio2 6 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
> +        data-hi-gpios = <&gpio2 7 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
> +
> +        /* devices */
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 23a67b32f095..91e573466d6b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -22519,6 +22519,11 @@ F:	Documentation/devicetree/bindings/wiegand/wiegand-controller.yaml
>   F:	drivers/wiegand/wiegand.c
>   F:	include/linux/wiegand.h
>   
> +WIEGAND GPIO BITBANG DRIVER
> +M:	Martin Zaťovič <m.zatovic1@gmail.com>
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/wiegand/wiegand-gpio.yaml
> +
>   WIIMOTE HID DRIVER
>   M:	David Rheinsberg <david.rheinsberg@gmail.com>
>   L:	linux-input@vger.kernel.org

-- 
Kind regards,
Evgeny Boger
CTO @ Wiren Board