Re: [PATCH v4 1/3] dt-bindings: trivial-devices: Add two I2C TPM devices

[Alexander Steffen]

On 02.06.22 15:48, Rob Herring wrote:
> On Thu, May 26, 2022 at 02:29:56PM +0200, Krzysztof Kozlowski wrote:
> > On 25/05/2022 18:58, Alexander Steffen wrote:
> > > Both are supported by the upcoming tpm_tis_i2c driver.
> > >
> > > Signed-off-by: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx>
> > > ---
> > >   Documentation/devicetree/bindings/trivial-devices.yaml | 4 ++++
> > >   1 file changed, 4 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/trivial-devices.yaml b/Documentation/devicetree/bindings/trivial-devices.yaml
> > > index 550a2e5c9e05..dc52822331dd 100644
> > > --- a/Documentation/devicetree/bindings/trivial-devices.yaml
> > > +++ b/Documentation/devicetree/bindings/trivial-devices.yaml
> > > @@ -135,6 +135,8 @@ properties:
> > >             - infineon,slb9635tt
> > >               # Infineon SLB9645 I2C TPM (new protocol, max 400khz)
> > >             - infineon,slb9645tt
> > > +            # Infineon SLB9673 I2C TPM 2.0
> > > +          - infineon,slb9673
> > >               # Infineon TLV493D-A1B6 I2C 3D Magnetic Sensor
> > >             - infineon,tlv493d-a1b6
> > >               # Infineon Multi-phase Digital VR Controller xdpe11280
> > > @@ -323,6 +325,8 @@ properties:
> > >             - st,24c256
> > >               # Ambient Light Sensor with SMBUS/Two Wire Serial Interface
> > >             - taos,tsl2550
> > > +            # TCG TIS-compliant TPM with I2C interface
> > > +          - tcg,tpm_tis-i2c
> >
> > One flavor uses tpm-tis, another tpm_tis... I guess it is too late to
> > make it consistent, but let's stick to the one more reasonable, so:
> > "tpm-tis-i2c".
>
> Neither should be used except perhaps as a fallback.

That is the intention, yes.

> Does 'TCG TIS-compliant TPM' encompass every property of a device? Power
> supplies, resets, interrupts, quirks, etc.?

In an ideal world, yes. In practice, of course implementations do have 
bugs that might require different workarounds. By selecting 
tcg,tpm-tis-i2c instead of anything more specific, you promise that the 
device is fully compliant to the TCG specification and does not require 
any such workarounds.

Alexander