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

[Jarkko Sakkinen]

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 at gmail.com>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
> > ---
> >  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 at linux.com>

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

/Jarkko