[03/15] dt-bindings: olpc, xo1.75-ec: Add OLPC XO-1.75 EC bindings

Message ID 20181010172300.317643-4-lkundrak@v3.sk
State Changes Requested
Headers show
Series
  • Add support for OLPC XO 1.75 Embedded Controller
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Commit Message

Lubomir Rintel Oct. 10, 2018, 5:22 p.m.
The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
signals for handshaking. It needs to know when is the slave (Linux)
side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
controller node) and when does it wish to respond with a command (the
cmd-gpio property).

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
---
 .../bindings/misc/olpc,xo1.75-ec.txt          | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt

Comments

Rob Herring Oct. 17, 2018, 7:38 p.m. | #1
On Wed, Oct 10, 2018 at 07:22:48PM +0200, Lubomir Rintel wrote:
> The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
> signals for handshaking. It needs to know when is the slave (Linux)
> side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
> controller node) and when does it wish to respond with a command (the
> cmd-gpio property).
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> ---
>  .../bindings/misc/olpc,xo1.75-ec.txt          | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> 
> diff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> new file mode 100644
> index 000000000000..14385fee65d2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> @@ -0,0 +1,24 @@
> +OLPC XO-1.75 Embedded Controller
> +
> +Required properties:
> +- compatible: Should be "olpc,xo1.75-ec".
> +- cmd-gpio: gpio specifier of the CMD pin

cmd-gpios

> +
> +The embedded controller requires the SPI controller driver to signal readiness
> +to receive a transfer (that is, when TX FIFO contains the response data) by
> +strobing the ACK pin with the ready signal. See the "ready-gpio" property of the

This will need updating based on the SPI binding.

> +SSP binding as documented in:
> +<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
> +
> +Example:
> +	&ssp3 {
> +		spi-slave;
> +		status = "okay";

Don't show status in examples.

> +		ready-gpio = <&gpio 125 GPIO_ACTIVE_HIGH>;
> +
> +		slave {
> +			compatible = "olpc,xo1.75-ec";
> +			spi-cpha;
> +			cmd-gpio = <&gpio 155 GPIO_ACTIVE_HIGH>;
> +		};
> +	};
> -- 
> 2.19.0
>
Pavel Machek Nov. 4, 2018, 12:26 p.m. | #2
On Wed 2018-10-10 19:22:48, Lubomir Rintel wrote:
> The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
> signals for handshaking. It needs to know when is the slave (Linux)
> side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
> controller node) and when does it wish to respond with a command (the
> cmd-gpio property).
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

Acked-by: Pavel Machek <pavel@ucw.cz>


> ---
>  .../bindings/misc/olpc,xo1.75-ec.txt          | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> 
> diff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> new file mode 100644
> index 000000000000..14385fee65d2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
> @@ -0,0 +1,24 @@
> +OLPC XO-1.75 Embedded Controller
> +
> +Required properties:
> +- compatible: Should be "olpc,xo1.75-ec".
> +- cmd-gpio: gpio specifier of the CMD pin
> +
> +The embedded controller requires the SPI controller driver to signal readiness
> +to receive a transfer (that is, when TX FIFO contains the response data) by
> +strobing the ACK pin with the ready signal. See the "ready-gpio" property of the
> +SSP binding as documented in:
> +<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
> +
> +Example:
> +	&ssp3 {
> +		spi-slave;
> +		status = "okay";
> +		ready-gpio = <&gpio 125 GPIO_ACTIVE_HIGH>;
> +
> +		slave {
> +			compatible = "olpc,xo1.75-ec";
> +			spi-cpha;
> +			cmd-gpio = <&gpio 155 GPIO_ACTIVE_HIGH>;
> +		};
> +	};

Patch

diff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
new file mode 100644
index 000000000000..14385fee65d2
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
@@ -0,0 +1,24 @@ 
+OLPC XO-1.75 Embedded Controller
+
+Required properties:
+- compatible: Should be "olpc,xo1.75-ec".
+- cmd-gpio: gpio specifier of the CMD pin
+
+The embedded controller requires the SPI controller driver to signal readiness
+to receive a transfer (that is, when TX FIFO contains the response data) by
+strobing the ACK pin with the ready signal. See the "ready-gpio" property of the
+SSP binding as documented in:
+<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
+
+Example:
+	&ssp3 {
+		spi-slave;
+		status = "okay";
+		ready-gpio = <&gpio 125 GPIO_ACTIVE_HIGH>;
+
+		slave {
+			compatible = "olpc,xo1.75-ec";
+			spi-cpha;
+			cmd-gpio = <&gpio 155 GPIO_ACTIVE_HIGH>;
+		};
+	};