Tegra234 and Tegra241 devices have QSPI controller that supports TPM
devices. Since the controller only supports half duplex, sw wait polling
method implemented in tpm_tis_spi does not suffice. Wait polling as per
protocol is a hardware feature.

Add compatible for Tegra TPM driver with hardware flow control.

Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
---
 .../security/tpm/nvidia,tegra-tpm-spi.yaml    | 34 +++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml

diff --git a/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml b/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml
new file mode 100644
index 000000000000..dcb78db7355c
--- /dev/null
+++ b/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/security/tpm/nvidia,tegra-tpm-spi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Tegra QSPI TPM driver
+
+maintainers:
+  - Thierry Reding <thierry.reding@gmail.com>
+  - Jonathan Hunter <jonathanh@nvidia.com>
+
+properties:
+  compatible:
+    enum:
+      - nvidia,tegra-tpm-spi
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    qspi1@3250000 {
+      tpm@0 {
+        compatible = "nvidia,tegra-tpm-spi";
+        reg = <0>;
+      };
+    };
-- 
2.17.1

On Fri, Feb 3, 2023 at 7:02 AM Krishna Yarlagadda
<kyarlagadda@nvidia.com> wrote:
>

Please use get_maintainers.pl. In particular, resend to DT list so
automated checks work.

> Tegra234 and Tegra241 devices have QSPI controller that supports TPM
> devices. Since the controller only supports half duplex, sw wait polling
> method implemented in tpm_tis_spi does not suffice. Wait polling as per
> protocol is a hardware feature.
>
> Add compatible for Tegra TPM driver with hardware flow control.
>
> Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
> ---
>  .../security/tpm/nvidia,tegra-tpm-spi.yaml    | 34 +++++++++++++++++++
>  1 file changed, 34 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml
>
> diff --git a/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml b/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml
> new file mode 100644
> index 000000000000..dcb78db7355c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/security/tpm/nvidia,tegra-tpm-spi.yaml
> @@ -0,0 +1,34 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/security/tpm/nvidia,tegra-tpm-spi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Tegra QSPI TPM driver

Bindings are for h/w, not drivers.

> +
> +maintainers:
> +  - Thierry Reding <thierry.reding@gmail.com>
> +  - Jonathan Hunter <jonathanh@nvidia.com>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - nvidia,tegra-tpm-spi
> +
> +  reg:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    qspi1@3250000 {

spi@...

> +      tpm@0 {
> +        compatible = "nvidia,tegra-tpm-spi";

Tegra has a TPM chip/block? This doesn't seem right.

> +        reg = <0>;
> +      };
> +    };
> --
> 2.17.1
>