Re: [PATCH RFC v4 07/10] dt-bindings: net: add binding for QCA7000 UART

From: Rob Herring
Date: Mon Mar 27 2017 - 16:31:17 EST


On Mon, Mar 27, 2017 at 8:37 AM, Stefan Wahren <stefan.wahren@xxxxxxxx> wrote:
> This is the serdev binding for the QCA7000 UART driver (Ethernet over UART).
>
> Signed-off-by: Stefan Wahren <stefan.wahren@xxxxxxxx>
> ---
>
> According to this binding are still some questions:
>
> Where should be the optional hardware flow control defined (at master or slave side)?

Probably should be in the slave side. We already have uart-has-rtscts
and rts/cts-gpios for the UART. Those mean we have RTS/CTS, but not
necessarily that we want to enable them.

In many cases, the driver may know what it needs.

> Is it okay to have two bindings (qca-qca7000-spi and qca-qca7000-uart) or should they be merged?

Are they mutually-exclusive or both are used at the same time? What
are the dependencies between the interfaces?

>
>
> .../devicetree/bindings/net/qca-qca7000-uart.txt | 31 ++++++++++++++++++++++
> 1 file changed, 31 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/qca-qca7000-uart.txt
>
> diff --git a/Documentation/devicetree/bindings/net/qca-qca7000-uart.txt b/Documentation/devicetree/bindings/net/qca-qca7000-uart.txt
> new file mode 100644
> index 0000000..f2e0450
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/qca-qca7000-uart.txt
> @@ -0,0 +1,31 @@
> +* Qualcomm QCA7000 (Ethernet over UART protocol)
> +
> +Note: This binding applies in case the QCA7000 is configured as a
> +UART slave device. It is possible to preconfigure the UART settings
> +of the QCA7000 firmware, which can't be changed during runtime.
> +
> +Required properties:
> +- compatible : Should be "qca,qca7000-uart"
> +
> +Optional properties:
> +- local-mac-address : 6 bytes, Specifies MAC address

The description can be "see ./ethernet.txt"

> +- current-speed : Specifies the serial device speed in
> + bits per second (default = 115200), which is
> + predefined by the QCA7000 firmware configuration

Add this to the slave binding doc with some caveats as to when this
should or should not be used as we discussed.

Rob