[PATCH 1/2] tpm: devicetree: document properties for cr50

[Andrey Pronin <apronin@chromium.org>]

Add TPM2.0-compatible interface to Cr50. Document its properties
in devicetree.

Signed-off-by: Andrey Pronin <apronin@chromium.org>
---
 .../devicetree/bindings/security/tpm/cr50_spi.txt  | 30 ++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/security/tpm/cr50_spi.txt

diff --git a/Documentation/devicetree/bindings/security/tpm/cr50_spi.txt b/Documentation/devicetree/bindings/security/tpm/cr50_spi.txt
new file mode 100644
index 0000000..1b05e51
--- /dev/null
+++ b/Documentation/devicetree/bindings/security/tpm/cr50_spi.txt
@@ -0,0 +1,30 @@
+* Cr50 Chip on SPI.
+
+TCG PTP FIFO Compliant Interface to Cr50 on SPI bus.
+
+Required properties:
+- compatible: Should be "google,cr50_spi".
+- spi-max-frequency: Maximum SPI frequency.
+
+Optional properties:
+- access-delay-msec: Required delay between subsequent transactions on SPI.
+- sleep-delay-msec: Time after the last SPI activity, after which the chip
+  may go to sleep.
+- wake-start-delay-msec: Time after initiating wake up before the chip is
+  ready to accept commands over SPI.
+
+Example:
+
+&spi0 {
+        status = "okay";
+
+        cr50@0 {
+                compatible = "google,cr50_spi";
+                reg = <0>;
+                spi-max-frequency = <800000>;
+
+                access-delay-msec = <2>;
+                sleep-delay-msec = <1000>;
+                wake-start-delay-msec = <60>;
+        };
+};
-- 
2.6.6