Re: [PATCH] tpm: turn on TPM on suspend for TPM 1.x

From: Jarkko Sakkinen
Date: Fri Mar 29 2019 - 05:41:30 EST


On Thu, Mar 28, 2019 at 06:19:26PM +0100, Domenico Andreoli wrote:
> On Fri, Mar 22, 2019 at 12:51:20PM +0200, Jarkko Sakkinen wrote:
> > tpm_chip_start/stop() should be also called for TPM 1.x devices on
> > suspend. Add that functionality back. Do not lock the chip because
> > it is unnecessary as there are no multiple threads using it when
> > doing the suspend.
> >
> > Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
> > Reported-by: Paul Zimmerman <pauldzim@xxxxxxxxx>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > ---
> > drivers/char/tpm/tpm-interface.c | 14 ++++++--------
> > 1 file changed, 6 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index 83ece5639f86..ae1030c9b086 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -402,15 +402,13 @@ int tpm_pm_suspend(struct device *dev)
> > if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
> > return 0;
> >
> > - if (chip->flags & TPM_CHIP_FLAG_TPM2) {
> > - mutex_lock(&chip->tpm_mutex);
> > - if (!tpm_chip_start(chip)) {
> > + if (!tpm_chip_start(chip)) {
> > + if (chip->flags & TPM_CHIP_FLAG_TPM2)
> > tpm2_shutdown(chip, TPM2_SU_STATE);
> > - tpm_chip_stop(chip);
> > - }
> > - mutex_unlock(&chip->tpm_mutex);
> > - } else {
> > - rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
> > + else
> > + rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
> > +
> > + tpm_chip_stop(chip);
> > }
> >
> > return rc;
>
> Tested-by: Domenico Andreoli <domenico.andreoli@xxxxxxxxx>

Thank you! I'll do a PR to James during the weekend.

/Jarkko