tpm: merge duplicate transmit_cmd() functions

Merged transmit_cmd() functions in tpm-interface.c and tpm-sysfs.c.
Added "tpm_" prefix for consistency sake. Changed cmd parameter as
opaque. This enables to use separate command structures for TPM1
and TPM2 commands in future. Loose coupling works fine here.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: two-phase chip management functions

tpm_register_hardware() and tpm_remove_hardware() are called often
before initializing the device. The problem is that the device might
not be fully initialized when it comes visible to the user space.

This patch resolves the issue by diving initialization into two
parts:

- tpmm_chip_alloc() creates struct tpm_chip.

- tpm_chip_register() sets up the character device and sysfs
  attributes.

The framework takes care of freeing struct tpm_chip by using the devres
API. The broken release callback has been wiped. ACPI drivers do not
ever get this callback.

Regards to Jason Gunthorpe for carefully reviewing this part of the
code.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: fix raciness of PPI interface lookup

Traversal of the ACPI device tree was not done right. PPI interface
should be looked up only from the ACPI device that is the platform
device for the TPM. This could cause problems with systems with
two TPM chips such as 4th gen Intel systems.

In addition, added the missing license and copyright platter to
the tpm_ppi.c.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: rename chip->dev to chip->pdev

Rename chip->dev to chip->pdev to make it explicit that this not the
character device but actually represents the platform device.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: device class for tpm

Added own device class for TPM. Uses MISC_MAJOR:TPM_MINOR for the
first character device in order to retain backwards compatibility.
Added tpm_dev_release() back attached to the character device.

I've been running this code now for a while on my laptop (Lenovo
T430S) TrouSerS works perfectly without modifications. I don't
believe it breaks anything significantly.

The sysfs attributes that have been placed under the wrong place
and are against sysfs-rules.txt should be probably left to
stagnate under platform device directory and start defining
new sysfs attributes to the char device directory.

Guidelines for future TPM sysfs attributes should be probably
along the lines of

- Single flat set of mandatory sysfs attributes. For example,
  current PPI interface is way way too rich when you only want
  to use it to clear and activate the TPM.

- Define sysfs attribute if and only if there's no way to get
  the value from ring-3. No attributes for TPM properties. It's
  just unnecessary maintenance hurdle that we don't want.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 baseline support

TPM 2.0 devices are separated by adding a field 'flags' to struct
tpm_chip and defining a flag TPM_CHIP_FLAG_TPM2 for tagging them.

This patch adds the following internal functions:

- tpm2_get_random()
- tpm2_get_tpm_pt()
- tpm2_pcr_extend()
- tpm2_pcr_read()
- tpm2_startup()

Additionally, the following exported functions are implemented for
implementing TPM 2.0 device drivers:

- tpm2_do_selftest()
- tpm2_calc_ordinal_durations()
- tpm2_gen_interrupt()

The existing functions that are exported for the use for existing
subsystems have been changed to check the flags field in struct
tpm_chip and use appropriate TPM 2.0 counterpart if
TPM_CHIP_FLAG_TPM2 is est.

The code for tpm2_calc_ordinal_duration() and tpm2_startup() were
originally written by Will Arthur.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Will Arthur <will.c.arthur@intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 CRB Interface

tpm_crb is a driver for TPM 2.0 Command Response Buffer (CRB) Interface
as defined in PC Client Platform TPM Profile (PTP) Specification.

Only polling and single locality is supported as these are the limitations
of the available hardware, Platform Trust Techonlogy (PTT) in Haswell
CPUs.

The driver always applies CRB with ACPI start because PTT reports using
only ACPI start as start method but as a result of my testing it requires
also CRB start.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 FIFO Interface

Detect TPM 2.0 by sending idempotent TPM 2.x command. Ordinals for
TPM 2.0 are higher than TPM 1.x commands so this should be fail-safe.
Using STS3 is unreliable because some chips just report 0xff and not
what the spec says.

Before TPM family is detected, timeouts are set to the maximum values
for both TPM 1.x and TPM 2.x. In addition to this, suspend/resume
functionality is implemented for TPM 2.x.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Will Arthur <will.c.arthur@intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>