Re: [PATCH 1/2] tpm: do not suspend/resume if power stays on

From: Jarkko Sakkinen
Date: Tue May 08 2018 - 06:56:23 EST


On Fri, May 04, 2018 at 07:27:13PM -0700, Greg KH wrote:
> On Wed, May 02, 2018 at 05:38:28PM +0300, Jarkko Sakkinen wrote:
> > From: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
> >
> > commit b5d0ebc99bf5d0801a5ecbe958caa3d68b8eaee8 upstream
> >
> > The suspend/resume behavior of the TPM can be controlled by setting
> > "powered-while-suspended" in the DTS. This is useful for the cases
> > when hardware does not power-off the TPM.
> >
> > Signed-off-by: Sonny Rao <sonnyrao@xxxxxxxxxxxx>
> > Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
> > Reviewed-by: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>
> > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Signed-off-by: James Morris <james.l.morris@xxxxxxxxxx>
> > ---
> > drivers/char/tpm/tpm-interface.c | 3 +++
> > drivers/char/tpm/tpm.h | 2 ++
> > drivers/char/tpm/tpm_of.c | 3 +++
> > 3 files changed, 8 insertions(+)
> >
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index 830d7e30e508..5463b649bdf1 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -969,6 +969,9 @@ int tpm_pm_suspend(struct device *dev)
> > if (chip == NULL)
> > return -ENODEV;
> >
> > + if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
> > + return 0;
> > +
> > if (chip->flags & TPM_CHIP_FLAG_TPM2) {
> > tpm2_shutdown(chip, TPM2_SU_STATE);
> > return 0;
> > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > index aa4299cf7e5a..41756a9e9ad8 100644
> > --- a/drivers/char/tpm/tpm.h
> > +++ b/drivers/char/tpm/tpm.h
> > @@ -143,6 +143,8 @@ enum tpm_chip_flags {
> > TPM_CHIP_FLAG_TPM2 = BIT(1),
> > TPM_CHIP_FLAG_IRQ = BIT(2),
> > TPM_CHIP_FLAG_VIRTUAL = BIT(3),
> > + TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4),
> > + TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5),
> > };
> >
> > struct tpm_chip {
> > diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
> > index 570f30c5c5f4..669f4a046398 100644
> > --- a/drivers/char/tpm/tpm_of.c
> > +++ b/drivers/char/tpm/tpm_of.c
> > @@ -37,6 +37,9 @@ int read_log(struct tpm_bios_log *log)
> > return -ENODEV;
> > }
> >
> > + if (of_property_read_bool(np, "powered-while-suspended"))
> > + chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
> > +
>
> This last line here blows up the build, there is no chip variable
> defined in this function :(
>
> So I have to drop both of these patches, from both 4.4.y and 4.9.y
> queues right now. Can you fix this up and resend them?
>
> thanks,
>
> greg k-h

Yes. Sorry. I'll do that.

/Jarkko