commit 448e9c55 upstream.

Some machines, such as the Acer C720 and Toshiba CB35, have TPMs that do
not send IRQs while also having an ACPI TPM entry indicating that they
will be sent. These machines freeze on resume while the tpm_tis module
waits for an IRQ, eventually timing out.

When in interrupt mode, the tpm_tis module should receive an IRQ during
module init. Fall back to polling mode if none is received when expected.
Signed-off-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Michael Mullin <masmullin@gmail.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
[phuewe: minor checkpatch fixed]
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>