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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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2005
KernelVersion: 2.6.12
Contact: tpmdd-devel@lists.sf.net
Description: The device/ directory under a specific TPM instance exposes
the properties of that TPM chip
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/active
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2006
KernelVersion: 2.6.17
Contact: tpmdd-devel@lists.sf.net
Description: The "active" property prints a '1' if the TPM chip is accepting
commands. An inactive TPM chip still contains all the state of
an active chip (Storage Root Key, NVRAM, etc), and can be
visible to the OS, but will only accept a restricted set of
commands. See the TPM Main Specification part 2, Structures,
section 17 for more information on which commands are
available.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/cancel
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: June 2005
KernelVersion: 2.6.13
Contact: tpmdd-devel@lists.sf.net
Description: The "cancel" property allows you to cancel the currently
pending TPM command. Writing any value to cancel will call the
TPM vendor specific cancel operation.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/caps
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2005
KernelVersion: 2.6.12
Contact: tpmdd-devel@lists.sf.net
Description: The "caps" property contains TPM manufacturer and version info.
Example output:
Manufacturer: 0x53544d20
TCG version: 1.2
Firmware version: 8.16
Manufacturer is a hex dump of the 4 byte manufacturer info
space in a TPM. TCG version shows the TCG TPM spec level that
the chip supports. Firmware version is that of the chip and
is manufacturer specific.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/durations
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: March 2011
KernelVersion: 3.1
Contact: tpmdd-devel@lists.sf.net
Description: The "durations" property shows the 3 vendor-specific values
used to wait for a short, medium and long TPM command. All
TPM commands are categorized as short, medium or long in
execution time, so that the driver doesn't have to wait
any longer than necessary before starting to poll for a
result.
Example output:
3015000 4508000 180995000 [original]
Here the short, medium and long durations are displayed in
usecs. "[original]" indicates that the values are displayed
unmodified from when they were queried from the chip.
Durations can be modified in the case where a buggy chip
reports them in msec instead of usec and they need to be
scaled to be displayed in usecs. In this case "[adjusted]"
will be displayed in place of "[original]".
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/enabled
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2006
KernelVersion: 2.6.17
Contact: tpmdd-devel@lists.sf.net
Description: The "enabled" property prints a '1' if the TPM chip is enabled,
meaning that it should be visible to the OS. This property
may be visible but produce a '0' after some operation that
disables the TPM.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/owned
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2006
KernelVersion: 2.6.17
Contact: tpmdd-devel@lists.sf.net
Description: The "owned" property produces a '1' if the TPM_TakeOwnership
ordinal has been executed successfully in the chip. A '0'
indicates that ownership hasn't been taken.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/pcrs
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2005
KernelVersion: 2.6.12
Contact: tpmdd-devel@lists.sf.net
Description: The "pcrs" property will dump the current value of all Platform
Configuration Registers in the TPM. Note that since these
values may be constantly changing, the output is only valid
for a snapshot in time.
Example output:
PCR-00: 3A 3F 78 0F 11 A4 B4 99 69 FC AA 80 CD 6E 39 57 C3 3B 22 75
PCR-01: 3A 3F 78 0F 11 A4 B4 99 69 FC AA 80 CD 6E 39 57 C3 3B 22 75
PCR-02: 3A 3F 78 0F 11 A4 B4 99 69 FC AA 80 CD 6E 39 57 C3 3B 22 75
PCR-03: 3A 3F 78 0F 11 A4 B4 99 69 FC AA 80 CD 6E 39 57 C3 3B 22 75
PCR-04: 3A 3F 78 0F 11 A4 B4 99 69 FC AA 80 CD 6E 39 57 C3 3B 22 75
...
The number of PCRs and hex bytes needed to represent a PCR
value will vary depending on TPM chip version. For TPM 1.1 and
1.2 chips, PCRs represent SHA-1 hashes, which are 20 bytes
long. Use the "caps" property to determine TPM version.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/pubek
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2005
KernelVersion: 2.6.12
Contact: tpmdd-devel@lists.sf.net
Description: The "pubek" property will return the TPM's public endorsement
key if possible. If the TPM has had ownership established and
is version 1.2, the pubek will not be available without the
owner's authorization. Since the TPM driver doesn't store any
secrets, it can't authorize its own request for the pubek,
making it unaccessible. The public endorsement key is gener-
Doc: ABI/stable: Fix typo in ABI/stable This patch fix some spelling typos in Documentation/ABI/stable. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-10-13 22:40:34 +08:00
ated at TPM manufacture time and exists for the life of the
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
chip.
Example output:
Algorithm: 00 00 00 01
Encscheme: 00 03
Sigscheme: 00 01
Parameters: 00 00 08 00 00 00 00 02 00 00 00 00
Modulus length: 256
Modulus:
B4 76 41 82 C9 20 2C 10 18 40 BC 8B E5 44 4C 6C
3A B2 92 0C A4 9B 2A 83 EB 5C 12 85 04 48 A0 B6
1E E4 81 84 CE B2 F2 45 1C F0 85 99 61 02 4D EB
86 C4 F7 F3 29 60 52 93 6B B2 E5 AB 8B A9 09 E3
D7 0E 7D CA 41 BF 43 07 65 86 3C 8C 13 7A D0 8B
82 5E 96 0B F8 1F 5F 34 06 DA A2 52 C1 A9 D5 26
0F F4 04 4B D9 3F 2D F2 AC 2F 74 64 1F 8B CD 3E
1E 30 38 6C 70 63 69 AB E2 50 DF 49 05 2E E1 8D
6F 78 44 DA 57 43 69 EE 76 6C 38 8A E9 8E A3 F0
A7 1F 3C A8 D0 12 15 3E CA 0E BD FA 24 CD 33 C6
47 AE A4 18 83 8E 22 39 75 93 86 E6 FD 66 48 B6
10 AD 94 14 65 F9 6A 17 78 BD 16 53 84 30 BF 70
E0 DC 65 FD 3C C6 B0 1E BF B9 C1 B5 6C EF B1 3A
F8 28 05 83 62 26 11 DC B4 6B 5A 97 FF 32 26 B6
F7 02 71 CF 15 AE 16 DD D1 C1 8E A8 CF 9B 50 7B
C3 91 FF 44 1E CF 7C 39 FE 17 77 21 20 BD CE 9B
Possible values:
Algorithm: TPM_ALG_RSA (1)
Encscheme: TPM_ES_RSAESPKCSv15 (2)
TPM_ES_RSAESOAEP_SHA1_MGF1 (3)
Sigscheme: TPM_SS_NONE (1)
Parameters, a byte string of 3 u32 values:
Key Length (bits): 00 00 08 00 (2048)
Num primes: 00 00 00 02 (2)
Exponent Size: 00 00 00 00 (0 means the
default exp)
Modulus Length: 256 (bytes)
Modulus: The 256 byte Endorsement Key modulus
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/temp_deactivated
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: April 2006
KernelVersion: 2.6.17
Contact: tpmdd-devel@lists.sf.net
Description: The "temp_deactivated" property returns a '1' if the chip has
Doc: ABI/stable: Fix typo in ABI/stable This patch fix some spelling typos in Documentation/ABI/stable. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-10-13 22:40:34 +08:00
been temporarily deactivated, usually until the next power
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
cycle. Whether a warm boot (reboot) will clear a TPM chip
from a temp_deactivated state is platform specific.
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: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-12-13 03:46:37 +08:00
What: /sys/class/tpm/tpmX/device/timeouts
tpm: add documentation for sysfs interfaces Reviewed-by: Peter Huewe <peter.huewe@infineon.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-11-08 07:00:45 +08:00
Date: March 2011
KernelVersion: 3.1
Contact: tpmdd-devel@lists.sf.net
Description: The "timeouts" property shows the 4 vendor-specific values
for the TPM's interface spec timeouts. The use of these
timeouts is defined by the TPM interface spec that the chip
conforms to.
Example output:
750000 750000 750000 750000 [original]
The four timeout values are shown in usecs, with a trailing
"[original]" or "[adjusted]" depending on whether the values
were scaled by the driver to be reported in usec from msecs.