Re: [PATCH v3 3/5] tpm: return error code from tpm_gen_interrupt()

[Jarkko Sakkinen]

On Tue, Jul 19, 2016 at 02:27:41PM -0600, Jason Gunthorpe wrote:
> On Tue, Jul 19, 2016 at 04:32:47PM +0300, Jarkko Sakkinen wrote:
> > Return error code from tpm_gen_interrupt() and fail tpm_tis family of
> > drivers on a system error. It doesn't make sense to continue if we
> > cannot even reach the TPM.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> >  drivers/char/tpm/tpm-interface.c | 6 +++---
> >  drivers/char/tpm/tpm.h           | 2 +-
> >  drivers/char/tpm/tpm_tis_core.c  | 4 +++-
> >  3 files changed, 7 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index 88dafcd..35b2722 100644
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -466,16 +466,16 @@ ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
> >   * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
> >   * a TPM error code.
> >   */
> > -void tpm_gen_interrupt(struct tpm_chip *chip)
> > +int tpm_gen_interrupt(struct tpm_chip *chip)
> 
> drivers/char/tpm/st33zp24/st33zp24.c needs to be updated too.
> 
> I looked at st33zp24.c and it looks broken, I don't see any logic that
> de-asserts TPM_CHIP_FLAG_IRQ if the irq test triggered by
> tpm_gen_interrupt, so presumably it should not be calling it at all.
> 
> IMHO, DT binding devices should never auto-probe IRQS anyhow, we only
> do it on PC because PC is insane...
> 
> If we fix st33 then I suggest just moving tpm_gen_interrupt into
> tpm_tis - nothing else should really be using it..

I'm happy to take fix for st33 but not the move because it does not
matter for the release.

/Jarkko