On Mon, May 09, 2022 at 02:50:18PM +0200, Stefan Mahnke-Hartmann wrote: > On 07.05.22 21:43, Jarkko Sakkinen wrote: > > On Fri, May 06, 2022 at 02:31:48PM +0200, Stefan Mahnke-Hartmann wrote: > >> TPM2_GetCapability with a capability that has the property type value > >> of TPM_PT_TOTAL_COMMANDS returns a zero length list, when an Infineon > >> TPM2 is in Field Upgrade mode. > >> Since an Infineon TPM2.0 in Field Upgrade mode returns RC_SUCCESS on > >> TPM2_Startup, the Field Upgrade mode has to be detected by > >> TPM2_GetCapability. > >> > >> Signed-off-by: Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@xxxxxxxxxxxx> > >> --- > >> drivers/char/tpm/tpm2-cmd.c | 6 ++++++ > >> 1 file changed, 6 insertions(+) > >> > >> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > >> index e62a644ce26b..659130e2936e 100644 > >> --- a/drivers/char/tpm/tpm2-cmd.c > >> +++ b/drivers/char/tpm/tpm2-cmd.c > >> @@ -746,6 +746,12 @@ int tpm2_auto_startup(struct tpm_chip *chip) > >> } > >> > >> rc = tpm2_get_cc_attrs_tbl(chip); > >> + /* > >> + * Infineon TPM in Field Upgrade mode will return no data for the number > >> + * of supported commands. > >> + */ > >> + if (rc == -ENODATA) > >> + rc = TPM2_RC_UPGRADE; > > > > Injecting hardware error codes like this is not considered a great idea. > > Resetting the error code was to avoid code duplication, while following the > same rationale as Mårten's patch. I can also add the -ENODATA to the if clause > below or duplicate the code block (similar to Mårten's). Do you have a better > suggestion? I'd do that instead. It documents better the conditions. BR, Jarkko
