<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/char/tpm, branch v6.0</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>tpm: Add check for Failure mode for TPM2 modules</title>
<updated>2022-08-03T20:56:20+00:00</updated>
<author>
<name>Mårten Lindahl</name>
<email>marten.lindahl@axis.com</email>
</author>
<published>2022-08-01T13:57:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=863ed94c589fcd1984f4e3080f069d30508044bb'/>
<id>863ed94c589fcd1984f4e3080f069d30508044bb</id>
<content type='text'>
In commit 0aa698787aa2 ("tpm: Add Upgrade/Reduced mode support for
TPM2 modules") it was said that:

"If the TPM is in Failure mode, it will successfully respond to both
tpm2_do_selftest() and tpm2_startup() calls. Although, will fail to
answer to tpm2_get_cc_attrs_tbl(). Use this fact to conclude that TPM
is in Failure mode."

But a check was never added in the commit when calling
tpm2_get_cc_attrs_tbl() to conclude that the TPM is in Failure mode.
This commit corrects this by adding a check.

Fixes: 0aa698787aa2 ("tpm: Add Upgrade/Reduced mode support for TPM2 modules")
Cc: stable@vger.kernel.org # v5.17+
Signed-off-by: Mårten Lindahl &lt;marten.lindahl@axis.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In commit 0aa698787aa2 ("tpm: Add Upgrade/Reduced mode support for
TPM2 modules") it was said that:

"If the TPM is in Failure mode, it will successfully respond to both
tpm2_do_selftest() and tpm2_startup() calls. Although, will fail to
answer to tpm2_get_cc_attrs_tbl(). Use this fact to conclude that TPM
is in Failure mode."

But a check was never added in the commit when calling
tpm2_get_cc_attrs_tbl() to conclude that the TPM is in Failure mode.
This commit corrects this by adding a check.

Fixes: 0aa698787aa2 ("tpm: Add Upgrade/Reduced mode support for TPM2 modules")
Cc: stable@vger.kernel.org # v5.17+
Signed-off-by: Mårten Lindahl &lt;marten.lindahl@axis.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: fix platform_no_drv_owner.cocci warning</title>
<updated>2022-08-03T20:56:20+00:00</updated>
<author>
<name>Yang Li</name>
<email>yang.lee@linux.alibaba.com</email>
</author>
<published>2022-07-01T09:13:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ffd056fa31779756d7146fb17325fb7872c98812'/>
<id>ffd056fa31779756d7146fb17325fb7872c98812</id>
<content type='text'>
Eliminate the following coccicheck warning:
./drivers/char/tpm/tpm_tis_i2c.c:379:3-8: No need to set .owner here.  The core will do it.

Remove .owner field if calls are used which set it automatically

Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Eliminate the following coccicheck warning:
./drivers/char/tpm/tpm_tis_i2c.c:379:3-8: No need to set .owner here.  The core will do it.

Remove .owner field if calls are used which set it automatically

Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: Add tpm_tis_i2c backend for tpm_tis_core</title>
<updated>2022-08-03T20:56:20+00:00</updated>
<author>
<name>Alexander Steffen</name>
<email>Alexander.Steffen@infineon.com</email>
</author>
<published>2022-06-08T17:31:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bbc23a07b0728c820d665d0054b2e2a6d01f0a98'/>
<id>bbc23a07b0728c820d665d0054b2e2a6d01f0a98</id>
<content type='text'>
Implement the TCG I2C Interface driver, as specified in the TCG PC
Client Platform TPM Profile (PTP) specification for TPM 2.0 v1.04
revision 14, section 8, I2C Interface Definition.

This driver supports Guard Times. That is, if required by the TPM, the
driver has to wait by a vendor-specific time after each I2C read/write.
The specific time is read from the TPM_I2C_INTERFACE_CAPABILITY register.

Unfortunately, the TCG specified almost but not quite compatible
register addresses. Therefore, the TIS register addresses need to be
mapped to I2C ones. The locality is stripped because for now, only
locality 0 is supported.

Add a sanity check to I2C reads of e.g. TPM_ACCESS and TPM_STS. This is
to detect communication errors and issues due to non-standard behaviour
(E.g. the clock stretching quirk in the BCM2835, see 4dbfb5f4401f). In
case the sanity check fails, attempt a retry.

Co-developed-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Co-developed-by: Amir Mizinski &lt;amirmizi6@gmail.com&gt;
Signed-off-by: Amir Mizinski &lt;amirmizi6@gmail.com&gt;
Signed-off-by: Alexander Steffen &lt;Alexander.Steffen@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement the TCG I2C Interface driver, as specified in the TCG PC
Client Platform TPM Profile (PTP) specification for TPM 2.0 v1.04
revision 14, section 8, I2C Interface Definition.

This driver supports Guard Times. That is, if required by the TPM, the
driver has to wait by a vendor-specific time after each I2C read/write.
The specific time is read from the TPM_I2C_INTERFACE_CAPABILITY register.

Unfortunately, the TCG specified almost but not quite compatible
register addresses. Therefore, the TIS register addresses need to be
mapped to I2C ones. The locality is stripped because for now, only
locality 0 is supported.

Add a sanity check to I2C reads of e.g. TPM_ACCESS and TPM_STS. This is
to detect communication errors and issues due to non-standard behaviour
(E.g. the clock stretching quirk in the BCM2835, see 4dbfb5f4401f). In
case the sanity check fails, attempt a retry.

Co-developed-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Co-developed-by: Amir Mizinski &lt;amirmizi6@gmail.com&gt;
Signed-off-by: Amir Mizinski &lt;amirmizi6@gmail.com&gt;
Signed-off-by: Alexander Steffen &lt;Alexander.Steffen@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: Add tpm_tis_verify_crc to the tpm_tis_phy_ops protocol layer</title>
<updated>2022-08-03T20:56:19+00:00</updated>
<author>
<name>Alexander Steffen</name>
<email>Alexander.Steffen@infineon.com</email>
</author>
<published>2022-06-08T17:31:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f25534a68b8e1ed8266d23b464a3b512364b124d'/>
<id>f25534a68b8e1ed8266d23b464a3b512364b124d</id>
<content type='text'>
Some TPMs, e.g. those implementing the I2C variant of TIS, can verify
data transfers to/from the FIFO with a CRC. The CRC is calculated over
the entirety of the FIFO register. Since the phy_ops layer is not aware
when the core layer is done reading/writing the FIFO, CRC verification
must be triggered from the core layer. To this end, add an optional
phy_ops API call.

Co-developed-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Alexander Steffen &lt;Alexander.Steffen@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some TPMs, e.g. those implementing the I2C variant of TIS, can verify
data transfers to/from the FIFO with a CRC. The CRC is calculated over
the entirety of the FIFO register. Since the phy_ops layer is not aware
when the core layer is done reading/writing the FIFO, CRC verification
must be triggered from the core layer. To this end, add an optional
phy_ops API call.

Co-developed-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Johannes Holland &lt;johannes.holland@infineon.com&gt;
Signed-off-by: Alexander Steffen &lt;Alexander.Steffen@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: Add upgrade/reduced mode support for TPM1.2 modules</title>
<updated>2022-08-03T20:56:19+00:00</updated>
<author>
<name>Stefan Mahnke-Hartmann</name>
<email>stefan.mahnke-hartmann@infineon.com</email>
</author>
<published>2022-06-03T08:41:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5e3a3f27cbded417e6d1ea2bb9739b572c09580e'/>
<id>5e3a3f27cbded417e6d1ea2bb9739b572c09580e</id>
<content type='text'>
In case a TPM in failure mode is detected, the TPM should be accessible
through a transparent communication channel for analysing purposes (e.g.
TPM_GetTestResult) or a field upgrade. Since a TPM in failure mode has
similar reduced functionality as in field upgrade mode, the flag
TPM_CHIP_FLAG_FIRMWARE_UPGRADE is also valid.

As described in TCG TPM Main Part1 Design Principles, Revision 116,
chapter 9.2.1. the TPM also allows an update function in case a TPM is
in failure mode.

If the TPM in failure mode is detected, the function tpm1_auto_startup()
sets TPM_CHIP_FLAG_FIRMWARE_UPGRADE flag, which is used later during
driver initialization/deinitialization to disable functionality which
makes no sense or will fail in the current TPM state. The following
functionality is affected:
 * Do not register TPM as a hwrng
 * Do not get pcr allocation
 * Do not register sysfs entries which provide information impossible to
   obtain in limited mode

Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In case a TPM in failure mode is detected, the TPM should be accessible
through a transparent communication channel for analysing purposes (e.g.
TPM_GetTestResult) or a field upgrade. Since a TPM in failure mode has
similar reduced functionality as in field upgrade mode, the flag
TPM_CHIP_FLAG_FIRMWARE_UPGRADE is also valid.

As described in TCG TPM Main Part1 Design Principles, Revision 116,
chapter 9.2.1. the TPM also allows an update function in case a TPM is
in failure mode.

If the TPM in failure mode is detected, the function tpm1_auto_startup()
sets TPM_CHIP_FLAG_FIRMWARE_UPGRADE flag, which is used later during
driver initialization/deinitialization to disable functionality which
makes no sense or will fail in the current TPM state. The following
functionality is affected:
 * Do not register TPM as a hwrng
 * Do not get pcr allocation
 * Do not register sysfs entries which provide information impossible to
   obtain in limited mode

Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'tpmdd-next-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd</title>
<updated>2022-05-24T20:16:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-05-24T20:16:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7cf6a8a17f5b134b7e783c2d45c53298faef82a7'/>
<id>7cf6a8a17f5b134b7e783c2d45c53298faef82a7</id>
<content type='text'>
Pull tpm updates from Jarkko Sakkinen:

 - Tightened validation of key hashes for SYSTEM_BLACKLIST_HASH_LIST. An
   invalid hash format causes a compilation error. Previously, they got
   included to the kernel binary but were silently ignored at run-time.

 - Allow root user to append new hashes to the blacklist keyring.

 - Trusted keys backed with Cryptographic Acceleration and Assurance
   Module (CAAM), which part of some of the new NXP's SoC's. Now there
   is total three hardware backends for trusted keys: TPM, ARM TEE and
   CAAM.

 - A scattered set of fixes and small improvements for the TPM driver.

* tag 'tpmdd-next-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  MAINTAINERS: add KEYS-TRUSTED-CAAM
  doc: trusted-encrypted: describe new CAAM trust source
  KEYS: trusted: Introduce support for NXP CAAM-based trusted keys
  crypto: caam - add in-kernel interface for blob generator
  crypto: caam - determine whether CAAM supports blob encap/decap
  KEYS: trusted: allow use of kernel RNG for key material
  KEYS: trusted: allow use of TEE as backend without TCG_TPM support
  tpm: Add field upgrade mode support for Infineon TPM2 modules
  tpm: Fix buffer access in tpm2_get_tpm_pt()
  char: tpm: cr50_i2c: Suppress duplicated error message in .remove()
  tpm: cr50: Add new device/vendor ID 0x504a6666
  tpm: Remove read16/read32/write32 calls from tpm_tis_phy_ops
  tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe()
  tpm/tpm_ftpm_tee: Return true/false (not 1/0) from bool functions
  certs: Explain the rationale to call panic()
  certs: Allow root user to append signed hashes to the blacklist keyring
  certs: Check that builtin blacklist hashes are valid
  certs: Make blacklist_vet_description() more strict
  certs: Factor out the blacklist hash creation
  tools/certs: Add print-cert-tbs-hash.sh
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tpm updates from Jarkko Sakkinen:

 - Tightened validation of key hashes for SYSTEM_BLACKLIST_HASH_LIST. An
   invalid hash format causes a compilation error. Previously, they got
   included to the kernel binary but were silently ignored at run-time.

 - Allow root user to append new hashes to the blacklist keyring.

 - Trusted keys backed with Cryptographic Acceleration and Assurance
   Module (CAAM), which part of some of the new NXP's SoC's. Now there
   is total three hardware backends for trusted keys: TPM, ARM TEE and
   CAAM.

 - A scattered set of fixes and small improvements for the TPM driver.

* tag 'tpmdd-next-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  MAINTAINERS: add KEYS-TRUSTED-CAAM
  doc: trusted-encrypted: describe new CAAM trust source
  KEYS: trusted: Introduce support for NXP CAAM-based trusted keys
  crypto: caam - add in-kernel interface for blob generator
  crypto: caam - determine whether CAAM supports blob encap/decap
  KEYS: trusted: allow use of kernel RNG for key material
  KEYS: trusted: allow use of TEE as backend without TCG_TPM support
  tpm: Add field upgrade mode support for Infineon TPM2 modules
  tpm: Fix buffer access in tpm2_get_tpm_pt()
  char: tpm: cr50_i2c: Suppress duplicated error message in .remove()
  tpm: cr50: Add new device/vendor ID 0x504a6666
  tpm: Remove read16/read32/write32 calls from tpm_tis_phy_ops
  tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe()
  tpm/tpm_ftpm_tee: Return true/false (not 1/0) from bool functions
  certs: Explain the rationale to call panic()
  certs: Allow root user to append signed hashes to the blacklist keyring
  certs: Check that builtin blacklist hashes are valid
  certs: Make blacklist_vet_description() more strict
  certs: Factor out the blacklist hash creation
  tools/certs: Add print-cert-tbs-hash.sh
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: Add field upgrade mode support for Infineon TPM2 modules</title>
<updated>2022-05-23T15:47:50+00:00</updated>
<author>
<name>Stefan Mahnke-Hartmann</name>
<email>stefan.mahnke-hartmann@infineon.com</email>
</author>
<published>2022-05-13T13:41:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=af402ee3c045b0cbd10b7e66d2431304ac9e69bb'/>
<id>af402ee3c045b0cbd10b7e66d2431304ac9e69bb</id>
<content type='text'>
TPM2_GetCapability with a capability that has the property type value
of TPM_PT_TOTAL_COMMANDS returns a zero length list, when an Infineon
TPM2 is in field upgrade mode.
Since an Infineon TPM2.0 in field upgrade mode returns RC_SUCCESS on
TPM2_Startup, the field upgrade mode has to be detected by
TPM2_GetCapability.

Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
TPM2_GetCapability with a capability that has the property type value
of TPM_PT_TOTAL_COMMANDS returns a zero length list, when an Infineon
TPM2 is in field upgrade mode.
Since an Infineon TPM2.0 in field upgrade mode returns RC_SUCCESS on
TPM2_Startup, the field upgrade mode has to be detected by
TPM2_GetCapability.

Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: Fix buffer access in tpm2_get_tpm_pt()</title>
<updated>2022-05-23T15:47:49+00:00</updated>
<author>
<name>Stefan Mahnke-Hartmann</name>
<email>stefan.mahnke-hartmann@infineon.com</email>
</author>
<published>2022-05-13T13:41:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e57b2523bd37e6434f4e64c7a685e3715ad21e9a'/>
<id>e57b2523bd37e6434f4e64c7a685e3715ad21e9a</id>
<content type='text'>
Under certain conditions uninitialized memory will be accessed.
As described by TCG Trusted Platform Module Library Specification,
rev. 1.59 (Part 3: Commands), if a TPM2_GetCapability is received,
requesting a capability, the TPM in field upgrade mode may return a
zero length list.
Check the property count in tpm2_get_tpm_pt().

Fixes: 2ab3241161b3 ("tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Under certain conditions uninitialized memory will be accessed.
As described by TCG Trusted Platform Module Library Specification,
rev. 1.59 (Part 3: Commands), if a TPM2_GetCapability is received,
requesting a capability, the TPM in field upgrade mode may return a
zero length list.
Check the property count in tpm2_get_tpm_pt().

Fixes: 2ab3241161b3 ("tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mahnke-Hartmann &lt;stefan.mahnke-hartmann@infineon.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>char: tpm: cr50_i2c: Suppress duplicated error message in .remove()</title>
<updated>2022-05-23T15:47:49+00:00</updated>
<author>
<name>Uwe Kleine-König</name>
<email>u.kleine-koenig@pengutronix.de</email>
</author>
<published>2022-04-26T08:06:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e0687fe958f763f1790f22ed5483025b7624e744'/>
<id>e0687fe958f763f1790f22ed5483025b7624e744</id>
<content type='text'>
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.

As tpm_cr50_i2c_remove() emits an error message already and the
additional error message by the i2c core doesn't add any useful
information, change the return value to zero to suppress this error
message.

Note that if i2c_clientdata is NULL, there is something really fishy.
Assuming no memory corruption happened (then all bets are lost anyhow),
tpm_cr50_i2c_remove() is only called after tpm_cr50_i2c_probe() returned
successfully. So there was a tpm chip registered before and after
tpm_cr50_i2c_remove() its privdata is freed but the associated character
device isn't removed. If after that happened userspace accesses the
character device it's likely that the freed memory is accessed. For that
reason the warning message is made a bit more frightening.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.

As tpm_cr50_i2c_remove() emits an error message already and the
additional error message by the i2c core doesn't add any useful
information, change the return value to zero to suppress this error
message.

Note that if i2c_clientdata is NULL, there is something really fishy.
Assuming no memory corruption happened (then all bets are lost anyhow),
tpm_cr50_i2c_remove() is only called after tpm_cr50_i2c_probe() returned
successfully. So there was a tpm chip registered before and after
tpm_cr50_i2c_remove() its privdata is freed but the associated character
device isn't removed. If after that happened userspace accesses the
character device it's likely that the freed memory is accessed. For that
reason the warning message is made a bit more frightening.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: cr50: Add new device/vendor ID 0x504a6666</title>
<updated>2022-05-23T15:47:49+00:00</updated>
<author>
<name>Jes B. Klinke</name>
<email>jbk@chromium.org</email>
</author>
<published>2022-04-19T23:37:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9c438fdef8906fe9c025e0106cef6fe491728790'/>
<id>9c438fdef8906fe9c025e0106cef6fe491728790</id>
<content type='text'>
Accept one additional numerical value of DID:VID for next generation
Google TPM with new firmware, to be used in future Chromebooks.

The TPM with the new firmware has the code name TI50, and is going to
use the same interfaces.

Signed-off-by: Jes B. Klinke &lt;jbk@chromium.org&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Accept one additional numerical value of DID:VID for next generation
Google TPM with new firmware, to be used in future Chromebooks.

The TPM with the new firmware has the code name TI50, and is going to
use the same interfaces.

Signed-off-by: Jes B. Klinke &lt;jbk@chromium.org&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
