This commit adds a dt-bindings document of PECI adapter driver for ASPEED
AST24xx/25xx SoCs.
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Joel Stanley <joel@xxxxxxxxx>
Cc: Andrew Jeffery <andrew@xxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx>
Cc: Milton Miller II <miltonm@xxxxxxxxxx>
Cc: Pavel Machek <pavel@xxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Ryan Chen <ryan_chen@xxxxxxxxxxxxxx>
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx>
Reviewed-by: James Feist <james.feist@xxxxxxxxxxxxxxx>
Reviewed-by: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
.../devicetree/bindings/peci/peci-aspeed.txt | 55 +++++++++++++++++++
1 file changed, 55 insertions(+)
create mode 100644 Documentation/devicetree/bindings/peci/peci-aspeed.txt
diff --git a/Documentation/devicetree/bindings/peci/peci-aspeed.txt b/Documentation/devicetree/bindings/peci/peci-aspeed.txt
new file mode 100644
index 000000000000..cdca73a3b7d8
--- /dev/null
+++ b/Documentation/devicetree/bindings/peci/peci-aspeed.txt
@@ -0,0 +1,55 @@
+Device tree configuration for PECI buses on the AST24XX and AST25XX SoCs.
+
+Required properties:
+- compatible : Should be one of:
+ "aspeed,ast2400-peci"
+ "aspeed,ast2500-peci"
+- reg : Should contain PECI controller registers location and
+ length.
+- #address-cells : Should be <1> required to define a client address.
+- #size-cells : Should be <0> required to define a client address.
+- interrupts : Should contain PECI controller interrupt.
+- clocks : Should contain clock source for PECI controller. Should
+ reference the external oscillator clock in the second
+ cell.
+- resets : Should contain phandle to reset controller with the reset
+ number in the second cell.
+- clock-frequency : Should contain the operation frequency of PECI controller
+ in units of Hz.
+ 187500 ~ 24000000
+
+Optional properties:
+- msg-timing : Message timing negotiation period. This value will
+ determine the period of message timing negotiation to be
+ issued by PECI controller. The unit of the programmed
+ value is four times of PECI clock period.
+ 0 ~ 255 (default: 1)
+- addr-timing : Address timing negotiation period. This value will
+ determine the period of address timing negotiation to be
+ issued by PECI controller. The unit of the programmed
+ value is four times of PECI clock period.
+ 0 ~ 255 (default: 1)
+- rd-sampling-point : Read sampling point selection. The whole period of a bit
+ time will be divided into 16 time frames. This value will
+ determine the time frame in which the controller will
+ sample PECI signal for data read back. Usually in the
+ middle of a bit time is the best.
+ 0 ~ 15 (default: 8)
+- cmd-timeout-ms : Command timeout in units of ms.
+ 1 ~ 60000 (default: 1000)
+
+Example:
+ peci0: peci-bus@0 {
+ compatible = "aspeed,ast2500-peci";
+ reg = <0x0 0x60>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ interrupts = <15>;
+ clocks = <&syscon ASPEED_CLK_GATE_REFCLK>;
+ resets = <&syscon ASPEED_RESET_PECI>;
+ clock-frequency = <24000000>;
+ msg-timing = <1>;
+ addr-timing = <1>;
+ rd-sampling-point = <8>;
+ cmd-timeout-ms = <1000>;
+ };
--
2.19.1
