[ Upstream commit e0687fe958 ]
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 <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Way back when this driver was written the I2C framework
used to insist an ID table be defined even if the driver
did not use it in favor of ACPI/OF matching, so it was
added just to placate the hard I2C framework requirement.
This is no longer the case so we can drop the table and
also convert the driver to the new probe interface.
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
disable_irq() after request_irq() still has a time gap in which
interrupts can come. request_irq() with IRQF_NO_AUTOEN flag will
disable IRQ auto-enable because of requesting.
Link: https://lore.kernel.org/patchwork/patch/1388765/
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: 3a253caaad ("char: tpm: add i2c driver for cr50")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Add TPM 2.0 compatible I2C interface for chips with cr50 firmware.
The firmware running on the currently supported H1 MCU requires a
special driver to handle its specific protocol, and this makes it
unsuitable to use tpm_tis_core_* and instead it must implement the
underlying TPM protocol similar to the other I2C TPM drivers.
- All 4 bytes of status register must be read/written at once.
- FIFO and burst count is limited to 63 and must be drained by AP.
- Provides an interrupt to indicate when read response data is ready
and when the TPM is finished processing write data.
This driver is based on the existing infineon I2C TPM driver, which
most closely matches the cr50 i2c protocol behavior.
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.com>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Tested-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
