On Thu, Nov 14, 2019 at 9:10 PM Rob Herring [off-list ref] wrote:

On Sun, Nov 10, 2019 at 06:21:36PM +0200, amirmizi6@gmail.com wrote:

quoted

From: Amir Mizinski <redacted>

this file aim at documenting TPM TIS I2C related dt-bindings for the I2C PTP based Physical TPM.

Signed-off-by: Amir Mizinski <redacted>
---
 .../bindings/security/tpm/tpm_tis_i2c.txt          | 24 ++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/security/tpm/tpm_tis_i2c.txt

Please make this a schema. See
Documentation/devicetree/writing-schema.rst.

quoted

diff --git a/Documentation/devicetree/bindings/security/tpm/tpm_tis_i2c.txt b/Documentation/devicetree/bindings/security/tpm/tpm_tis_i2c.txt
new file mode 100644
index 0000000..7d5a69e
--- /dev/null
+++ b/Documentation/devicetree/bindings/security/tpm/tpm_tis_i2c.txt

@@ -0,0 +1,24 @@
+* Device Tree Bindings for I2C PTP based Trusted Platform Module(TPM)
+
+The TCG defines hardware protocol, registers and interface (based
+on the TPM Interface Specification) for accessing TPM devices
+implemented with an I2C interface.
+
+Refer to the 'I2C Interface Definition' section in 'TCG PC Client
+PlatformTPMProfile(PTP) Specification' publication for specification.
+
+Required properties:
+
+- compatible     : Should be "tcg,tpm_tis-i2c"

s/_/-/

As this has to be under an I2C controller node, the '-i2c' part is
redundant.

I wrote this Respectively with the tpm_tis-spi driver.
https://github.com/torvalds/linux/blob/master/Documentation/devicetree/bindings/security/tpm/tpm_tis_spi.txt
Should i change it anyway or keep the format?
Also the '-i2c' is added since its not the only protocol used over
tis, and it is handled differently from spi.

There's a bigger issue that the h/w here is more than just an I2C
protocol. The chip may have multiple power supplies, clocks, reset
lines, etc. HID over I2C seems like a similar case. Does the spec define
*all* of that? If not, you need chip specific compatibles. You can keep
this as a fallback though.

quoted

+- reg            : Address on the bus
+- tpm-pirq       : Input gpio pin, used for host interrupts

GPIO connections are properties ending in '-gpios'. However, if the only
use is an interrupt, then you should use 'interrupts'.

My mistake, i didn't implemented interrupts yet so ill clear this for
now.  thank you.

quoted

+
+Example (for Raspberry Pie 3 Board with Nuvoton's NPCT75X (2.0)
+-------------------------------------------------------------------
+
+tpm_tis-i2c: tpm_tis-i2c@2e {
+
+       compatible = "tcg,tpm_tis-i2c";
+       reg = <0x2e>;
+       tpm-pirq = <&gpio 24 GPIO_ACTIVE_HIGH>;
+};
--
2.7.4

Apologies for the late response, had a personal issue that needed my attention
I'm working on making this a schema for next version. This is new for
me, if you have additional sources regarding how to write it, i'll
appreciate if you send me.
Thank you.

Amir Mizinski