Re: [tpmdd-devel] [PATCH] tpm: fix suspend/resume paths for TPM 2.0

From: Scot Doyle
Date: Tue Jan 27 2015 - 11:54:14 EST


On Tue, 27 Jan 2015, Jarkko Sakkinen wrote:
> Fixed suspend/resume paths for TPM 2.0 and consolidated all the
> associated code to the tpm_pm_suspend() and tpm_pm_resume()
> functions. Resume path should be handled by the firmware, i.e.
> Startup(CLEAR) for hibernate and Startup(STATE) for suspend.
>
> There might be some non-PC embedded devices in the future where
> Startup() is not the handled by the FW but fixing the code for
> those IMHO should be postponed until there is hardware available
> to test the fixes although extra Startup in the driver code is
> essentially a NOP.
>
> Reported-by: Peter Hüwe <PeterHuewe@xxxxxx>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> ---

...

> --- a/drivers/char/tpm/tpm_tis.c
> +++ b/drivers/char/tpm/tpm_tis.c
> @@ -865,25 +865,23 @@ static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
> static int tpm_tis_resume(struct device *dev)
> {

...

> + /* TPM 1.2 requires self-test on resume. */
> + if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
> + ret = tpm_do_selftest(chip);
> + if (ret < 0)
> + return ret;

Just to note, the return value from tpm_do_selftest() on TPM 1.2 chips was
previously ignored. Mine does return 0.