Re: [PATCH v3 1/6] spi: Document DT bindings for SPI controllers in slave mode
From: Rob Herring
Date: Mon May 08 2017 - 12:55:10 EST
On Thu, May 04, 2017 at 07:45:46PM +0200, Geert Uytterhoeven wrote:
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> v3:
> - In SPI slave mode, represent the (single) slave device again as a
> child of the controller node, which is now optional, and must be
> named "slave" if present,
> - Split slave node properties in master mode, slave mode, and common
> properties,
>
> v2:
> - Do not create a child node in SPI slave mode. Instead, add an
> "spi-slave" property, and put the mode properties in the controller
> node.
> ---
> Documentation/devicetree/bindings/spi/spi-bus.txt | 76 ++++++++++++++---------
> 1 file changed, 45 insertions(+), 31 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt
> index 4b1d6e74c744fe96..1f6e86f787efd229 100644
> --- a/Documentation/devicetree/bindings/spi/spi-bus.txt
> +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt
> @@ -1,17 +1,23 @@
> SPI (Serial Peripheral Interface) busses
>
> -SPI busses can be described with a node for the SPI master device
> -and a set of child nodes for each SPI slave on the bus. For this
> -discussion, it is assumed that the system's SPI controller is in
> -SPI master mode. This binding does not describe SPI controllers
> -in slave mode.
> +SPI busses can be described with a node for the SPI controller device
> +and a set of child nodes for each SPI slave on the bus. The system's SPI
> +controller may be described for use in SPI master mode or in SPI slave mode,
> +but not for both at the same time.
>
> -The SPI master node requires the following properties:
> +The SPI controller node requires the following properties:
> +- compatible - Name of SPI bus controller following generic names
> + recommended practice.
> +
> +In master mode, the SPI controller node requires the following additional
> +properties:
> - #address-cells - number of cells required to define a chip select
> address on the SPI bus.
> - #size-cells - should be zero.
> -- compatible - name of SPI bus controller following generic names
> - recommended practice.
> +
> +In slave mode, the SPI controller node requires one additional property:
> +- spi-slave - Empty property.
Do we still need this if we have a child node called "slave".
Otherwise,
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>