bindings/tpm/tcg,tpm-tis-i2c.yaml

   1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/tpm/tcg,tpm-tis-i2c.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: I²C-attached Trusted Platform Module conforming to TCG TIS specification
   8
   9 maintainers:
  10   - Lukas Wunner <lukas@wunner.de>
  11
  12 description: |
  13   The Trusted Computing Group (TCG) has defined a multi-vendor standard
  14   for accessing a TPM chip.  It can be transported over various buses,
  15   one of them being I²C.  The standard is named:
  16   TCG PC Client Specific TPM Interface Specification (TIS)
  17   https://trustedcomputinggroup.org/resource/pc-client-work-group-pc-client-specific-tpm-interface-specification-tis/
  18
  19   The I²C interface was not originally part of the standard, but added
  20   in 2017 with a separate document:
  21   TCG PC Client Platform TPM Profile Specification for TPM 2.0 (PTP)
  22   https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
  23
  24   Recent TPM 2.0 chips conform to this generic interface, others use a
  25   vendor-specific I²C interface.
  26
  27 properties:
  28   compatible:
  29     oneOf:
  30       - description: Generic TPM 2.0 chips conforming to TCG PTP interface
  31         items:
  32           - enum:
  33               - infineon,slb9673
  34               - nuvoton,npct75x
  35           - const: tcg,tpm-tis-i2c
  36
  37       - description: TPM 1.2 and 2.0 chips with vendor-specific I²C interface
  38         items:
  39           - enum:
  40               - atmel,at97sc3204t # TPM 1.2
  41               - infineon,slb9635tt # TPM 1.2 (maximum 100 kHz)
  42               - infineon,slb9645tt # TPM 1.2 (maximum 400 kHz)
  43               - infineon,tpm_i2c_infineon # TPM 1.2
  44               - nuvoton,npct501 # TPM 1.2
  45               - nuvoton,npct601 # TPM 2.0
  46               - st,st33zp24-i2c # TPM 2.0
  47               - winbond,wpct301 # TPM 1.2
  48
  49   reg:
  50     description: address of TPM on the I²C bus
  51
  52 allOf:
  53   - $ref: tpm-common.yaml#
  54
  55 required:
  56   - compatible
  57   - reg
  58
  59 unevaluatedProperties: false
  60
  61 examples:
  62   - |
  63     i2c {
  64         #address-cells = <1>;
  65         #size-cells = <0>;
  66
  67         tpm@57 {
  68             label = "tpm";
  69             compatible = "nuvoton,npct601";
  70             reg = <0x57>;
  71             linux,sml-base = <0x7f 0xfd450000>;
  72             linux,sml-size = <0x10000>;
  73         };
  74     };
  75
  76   - |
  77     #include <dt-bindings/gpio/gpio.h>
  78     #include <dt-bindings/interrupt-controller/irq.h>
  79     i2c {
  80         #address-cells = <1>;
  81         #size-cells = <0>;
  82
  83         tpm@13 {
  84             reg = <0x13>;
  85             compatible = "st,st33zp24-i2c";
  86             interrupt-parent = <&gpio5>;
  87             interrupts = <7 IRQ_TYPE_LEVEL_HIGH>;
  88             lpcpd-gpios = <&gpio5 15 GPIO_ACTIVE_HIGH>;
  89         };
  90     };