tpm, tpm_tis: fix tpm_tis ACPI detection issue with TPM 2.0
authorJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Mon, 28 Sep 2015 21:32:19 +0000 (00:32 +0300)
committerPeter Huewe <peterhuewe@gmx.de>
Sun, 18 Oct 2015 23:01:14 +0000 (01:01 +0200)
commit399235dc6e95400a1322a9999e92073bc572f0c8
treeda5b36115c8e3a7681e649d7ec4791dc6ce503a0
parent149789ce9d472e6b4fd99336e779ab843754a96c
tpm, tpm_tis: fix tpm_tis ACPI detection issue with TPM 2.0

Both for FIFO and CRB interface TCG has decided to use the same HID
MSFT0101. They can be differentiated by looking at the start method from
TPM2 ACPI table. This patches makes necessary fixes to tpm_tis and
tpm_crb modules in order to correctly detect, which module should be
used.

For MSFT0101 we must use struct acpi_driver because struct pnp_driver
has a 7 character limitation.

It turned out that the root cause in b371616b8 was not correct for
https://bugzilla.kernel.org/show_bug.cgi?id=98181.

v2:

* One fixup was missing from v1: is_tpm2_fifo -> is_fifo

v3:

* Use pnp_driver for existing HIDs and acpi_driver only for MSFT0101 in
  order ensure backwards compatibility.

v4:

* Check for FIFO before doing *anything* in crb_acpi_add().
* There was return immediately after acpi_bus_unregister_driver() in
  cleanup_tis(). This caused pnp_unregister_driver() not to be called.

Cc: stable@kernel.org
Reported-by: Michael Saunders <mick.saunders@gmail.com>
Reported-by: Michael Marley <michael@michaelmarley.com>
Reported-by: Jethro Beekman <kernel@jbeekman.nl>
Reported-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Michael Marley <michael@michaelmarley.com>
Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (on TPM 1.2)
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
drivers/char/tpm/tpm.h
drivers/char/tpm/tpm_crb.c
drivers/char/tpm/tpm_tis.c