linux-stable.git/drivers/i2c, branch v5.4.263

i2c: i801: fix potential race in i801_block_transaction_byte_by_byte

2023-11-28T16:50:21+00:00

commit f78ca48a8ba9cdec96e8839351e49eec3233b177 upstream.

Currently we set SMBHSTCNT_LAST_BYTE only after the host has started
receiving the last byte. If we get e.g. preempted before setting
SMBHSTCNT_LAST_BYTE, the host may be finished with receiving the byte
before SMBHSTCNT_LAST_BYTE is set.
Therefore change the code to set SMBHSTCNT_LAST_BYTE before writing
SMBHSTSTS_BYTE_DONE for the byte before the last byte. Now the code
is also consistent with what we do in i801_isr_byte_done().

Reported-by: Jean Delvare 
Closes: https://lore.kernel.org/linux-i2c/20230828152747.09444625@endymion.delvare/
Cc: stable@vger.kernel.org
Acked-by: Andi Shyti 
Signed-off-by: Heiner Kallweit 
Reviewed-by: Jean Delvare 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: core: Run atomic i2c xfer when !preemptible

2023-11-28T16:50:19+00:00

commit aa49c90894d06e18a1ee7c095edbd2f37c232d02 upstream.

Since bae1d3a05a8b, i2c transfers are non-atomic if preemption is
disabled. However, non-atomic i2c transfers require preemption (e.g. in
wait_for_completion() while waiting for the DMA).

panic() calls preempt_disable_notrace() before calling
emergency_restart(). Therefore, if an i2c device is used for the
restart, the xfer should be atomic. This avoids warnings like:

[   12.667612] WARNING: CPU: 1 PID: 1 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x33c/0x6b0
[   12.676926] Voluntary context switch within RCU read-side critical section!
...
[   12.742376]  schedule_timeout from wait_for_completion_timeout+0x90/0x114
[   12.749179]  wait_for_completion_timeout from tegra_i2c_wait_completion+0x40/0x70
...
[   12.994527]  atomic_notifier_call_chain from machine_restart+0x34/0x58
[   13.001050]  machine_restart from panic+0x2a8/0x32c

Use !preemptible() instead, which is basically the same check as
pre-v5.2.

Fixes: bae1d3a05a8b ("i2c: core: remove use of in_atomic()")
Cc: stable@vger.kernel.org # v5.2+
Suggested-by: Dmitry Osipenko 
Acked-by: Wolfram Sang 
Reviewed-by: Dmitry Osipenko 
Tested-by: Nishanth Menon 
Signed-off-by: Benjamin Bara 
Link: https://lore.kernel.org/r/20230327-tegra-pmic-reboot-v7-2-18699d5dcd76@skidata.com
Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman

i2c: sun6i-p2wi: Prevent potential division by zero

2023-11-28T16:50:15+00:00

[ Upstream commit 5ac61d26b8baff5b2e5a9f3dc1ef63297e4b53e7 ]

Make sure we don't OOPS in case clock-frequency is set to 0 in a DT. The
variable set here is later used as a divisor.

Signed-off-by: Axel Lin 
Acked-by: Boris Brezillon 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: aspeed: Fix i2c bus hang in slave read

2023-11-08T10:23:37+00:00

commit 54f1840ddee9bbdc8dd89fbbfdfa632401244146 upstream.

When the `CONFIG_I2C_SLAVE` option is enabled and the device operates
as a slave, a situation arises where the master sends a START signal
without the accompanying STOP signal. This action results in a
persistent I2C bus timeout. The core issue stems from the fact that
the i2c controller remains in a slave read state without a timeout
mechanism. As a consequence, the bus perpetually experiences timeouts.

In this case, the i2c bus will be reset, but the slave_state reset is
missing.

Fixes: fee465150b45 ("i2c: aspeed: Reset the i2c controller when timeout occurs")
Signed-off-by: Jian Zhang 
Acked-by: Andi Shyti 
Tested-by: Andrew Jeffery 
Reviewed-by: Andrew Jeffery 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: stm32f7: Fix PEC handling in case of SMBUS transfers

2023-11-08T10:23:37+00:00

commit c896ff2dd8f30a6b0a922c83a96f6d43f05f0e92 upstream.

In case of SMBUS byte read with PEC enabled, the whole transfer
is split into two commands.  A first write command, followed by
a read command.  The write command does not have any PEC byte
and a PEC byte is appended at the end of the read command.
(cf Read byte protocol with PEC in SMBUS specification)

Within the STM32 I2C controller, handling (either sending
or receiving) of the PEC byte is done via the PECBYTE bit in
register CR2.

Currently, the PECBYTE is set at the beginning of a transfer,
which lead to sending a PEC byte at the end of the write command
(hence losing the real last byte), and also does not check the
PEC byte received during the read command.

This patch corrects the function stm32f7_i2c_smbus_xfer_msg
in order to only set the PECBYTE during the read command.

Fixes: 9e48155f6bfe ("i2c: i2c-stm32f7: Add initial SMBus protocols support")
Signed-off-by: Alain Volmat 
Reviewed-by: Pierre-Yves MORDRET 
Acked-by: Andi Shyti 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: muxes: i2c-demux-pinctrl: Use of_get_i2c_adapter_by_node()

2023-11-08T10:23:36+00:00

commit 0fb118de5003028ad092a4e66fc6d07b86c3bc94 upstream.

i2c-demux-pinctrl uses the pair of_find_i2c_adapter_by_node() /
i2c_put_adapter(). These pair alone is not correct to properly lock the
I2C parent adapter.

Indeed, i2c_put_adapter() decrements the module refcount while
of_find_i2c_adapter_by_node() does not increment it. This leads to an
underflow of the parent module refcount.

Use the	dedicated function, of_get_i2c_adapter_by_node(), to handle
correctly the module refcount.

Fixes: 50a5ba876908 ("i2c: mux: demux-pinctrl: add driver")
Signed-off-by: Herve Codina 
Cc: stable@vger.kernel.org
Acked-by: Peter Rosin 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node()

2023-11-08T10:23:36+00:00

commit 3dc0ec46f6e7511fc4fdf6b6cda439382bc957f1 upstream.

i2c-mux-gpmux uses the pair of_find_i2c_adapter_by_node() /
i2c_put_adapter(). These pair alone is not correct to properly lock the
I2C parent adapter.

Indeed, i2c_put_adapter() decrements the module refcount while
of_find_i2c_adapter_by_node() does not increment it. This leads to an
underflow of the parent module refcount.

Use the dedicated function, of_get_i2c_adapter_by_node(), to handle
correctly the module refcount.

Fixes: ac8498f0ce53 ("i2c: i2c-mux-gpmux: new driver")
Signed-off-by: Herve Codina 
Cc: stable@vger.kernel.org
Acked-by: Peter Rosin 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: muxes: i2c-mux-pinctrl: Use of_get_i2c_adapter_by_node()

2023-11-08T10:23:36+00:00

commit 3171d37b58a76e1febbf3f4af2d06234a98cf88b upstream.

i2c-mux-pinctrl uses the pair of_find_i2c_adapter_by_node() /
i2c_put_adapter(). These pair alone is not correct to properly lock the
I2C parent adapter.

Indeed, i2c_put_adapter() decrements the module refcount while
of_find_i2c_adapter_by_node() does not increment it. This leads to an
underflow of the parent module refcount.

Use the dedicated function, of_get_i2c_adapter_by_node(), to handle
correctly the module refcount.

Fixes: c4aee3e1b0de ("i2c: mux: pinctrl: remove platform_data")
Signed-off-by: Herve Codina 
Cc: stable@vger.kernel.org
Acked-by: Peter Rosin 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: mux: Avoid potential false error message in i2c_mux_add_adapter

2023-10-25T09:53:23+00:00

[ Upstream commit b13e59e74ff71a1004e0508107e91e9a84fd7388 ]

I2C_CLASS_DEPRECATED is a flag and not an actual class.
There's nothing speaking against both, parent and child, having
I2C_CLASS_DEPRECATED set. Therefore exclude it from the check.

Signed-off-by: Heiner Kallweit 
Acked-by: Peter Rosin 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: i801: unregister tco_pdev in i801_probe() error path

2023-10-10T19:46:41+00:00

commit 3914784553f68c931fc666dbe7e86fe881aada38 upstream.

We have to unregister tco_pdev also if i2c_add_adapter() fails.

Fixes: 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs")
Cc: stable@vger.kernel.org
Signed-off-by: Heiner Kallweit 
Reviewed-by: Mika Westerberg 
Reviewed-by: Jean Delvare 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman