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

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

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@collabora.com>
> > 
> > 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@chromium.org>
> > Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> > Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > Signed-off-by: James Morris <james.l.morris@oracle.com>
> > ---
> >  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