• Jarkko Sakkinen's avatar
    tpm: fix suspend/resume paths for TPM 2.0 · 74d6b3ce
    Jarkko Sakkinen authored
    Fixed suspend/resume paths for TPM 2.0 and consolidated all the
    associated code to the tpm_pm_suspend() and tpm_pm_resume()
    functions. Resume path should be handled by the firmware, i.e.
    Startup(CLEAR) for hibernate and Startup(STATE) for suspend.
    
    There might be some non-PC embedded devices in the future where
    Startup() is not the handled by the FW but fixing the code for
    those IMHO should be postponed until there is hardware available
    to test the fixes although extra Startup in the driver code is
    essentially a NOP.
    
    Added Shutdown(CLEAR) to the remove paths of TIS and CRB drivers.
    Changed tpm2_shutdown() to a void function because there isn't
    much you can do except print an error message if this fails with
    a system error.
    
    Fixes: aec04cbd ("tpm: TPM 2.0 FIFO Interface")
    Fixes: 30fc8d13 ("tpm: TPM 2.0 CRB Interface")
    [phuewe: both did send TPM_Shutdown on resume which 'disables' the TPM
    and did not send TPM2_Shutdown on teardown which leads some TPM2.0 to
    believe there was an attack (no TPM2_Shutdown = no orderly shutdown =
    attack)]
    Reported-by: default avatarPeter Hüwe <PeterHuewe@gmx.de>
    Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
    Tested-by: default avatarScot Doyle <lkml14@scotdoyle.com>
    Reviewed-by: default avatarPeter Huewe <peterhuewe@gmx.de>
    Signed-off-by: default avatarPeter Huewe <peterhuewe@gmx.de>
    74d6b3ce
tpm_crb.c 7.73 KB