tpm_tis: verify interrupt during init
authorScot Doyle <lkml14@scotdoyle.com>
Wed, 24 Sep 2014 22:41:10 +0000 (22:41 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 6 Mar 2015 22:40:50 +0000 (14:40 -0800)
commit8716dbb11fc845a2fa28d889efe638b9dae86daf
tree769239762318a21542a370f33b2c378799189ee0
parent49d9336fac46885eb0b6ddf5072f3e20bdfdbdce
tpm_tis: verify interrupt during init

commit 448e9c55c12d6bd4fa90a7e31d802e045666d7c8 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/char/tpm/tpm_tis.c