• Jerry Snitselaar's avatar
    tpm_tis: Disable interrupts on ThinkPad T490s · b154ce11
    Jerry Snitselaar authored
    There is a misconfiguration in the bios of the gpio pin used for the
    interrupt in the T490s. When interrupts are enabled in the tpm_tis
    driver code this results in an interrupt storm. This was initially
    reported when we attempted to enable the interrupt code in the tpm_tis
    driver, which previously wasn't setting a flag to enable it. Due to
    the reports of the interrupt storm that code was reverted and we went back
    to polling instead of using interrupts. Now that we know the T490s problem
    is a firmware issue, add code to check if the system is a T490s and
    disable interrupts if that is the case. This will allow us to enable
    interrupts for everyone else. If the user has a fixed bios they can
    force the enabling of interrupts with tpm_tis.interrupts=1 on the
    kernel command line.
    
    Cc: Peter Huewe <peterhuewe@gmx.de>
    Cc: Jason Gunthorpe <jgg@ziepe.ca>
    Cc: Hans de Goede <hdegoede@redhat.com>
    Signed-off-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
    Reviewed-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
    Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
    Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
    Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
    b154ce11
tpm_tis.c 9.54 KB