Re: [PATCH] tpm: do not suspend/resume if power stays on

From: Mark Rutland
Date: Wed Mar 01 2017 - 08:56:01 EST


On Wed, Mar 01, 2017 at 12:51:16PM +0100, Enric Balletbo i Serra wrote:
> From: Sonny Rao <sonnyrao@xxxxxxxxxxxx>
>
> The suspend/resume behavior of the TPM can be controlled
> by setting "powered-while-suspended" in the DTS.
>
> Signed-off-by: Sonny Rao <sonnyrao@xxxxxxxxxxxx>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/tpm/tpm.txt | 25 +++++++++++++++++++++++++
> drivers/char/tpm/tpm_i2c_infineon.c | 25 ++++++++++++++++++++++++-
> 2 files changed, 49 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/tpm/tpm.txt
>
> diff --git a/Documentation/devicetree/bindings/tpm/tpm.txt b/Documentation/devicetree/bindings/tpm/tpm.txt
> new file mode 100644
> index 0000000..af4de0d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/tpm/tpm.txt
> @@ -0,0 +1,25 @@
> +TPM (Trusted Platform Module)
> +
> +A TPM on the I2C bus is a child of the node for the bus.
> +
> +Required properties:
> +- compatible: should be "infineon,<chip>"
> +- reg: the I2C address
> +
> +Optional properties:
> +- powered-while-suspended: present when the TPM is left powered on between
> + suspend and resume (makes the suspend/resume callbacks do nothing).

This reads like configuration rather than a HW property.

Why do you want this property?

Thanks,
Mark.