i2c: stm32f7: Do not prepare/unprepare clock during runtime suspend/resume

In case there is any sort of clock controller attached to this I2C bus
controller, for example Versaclock or even an AIC32x

i2c: stm32f7: Do not prepare/unprepare clock during runtime suspend/resume

In case there is any sort of clock controller attached to this I2C bus
controller, for example Versaclock or even an AIC32x4 I2C codec, then
an I2C transfer triggered from the clock controller clk_ops .prepare
callback may trigger a deadlock on drivers/clk/clk.c prepare_lock mutex.

This is because the clock controller first grabs the prepare_lock mutex
and then performs the prepare operation, including its I2C access. The
I2C access resumes this I2C bus controller via .runtime_resume callback,
which calls clk_prepare_enable(), which attempts to grab the prepare_lock
mutex again and deadlocks.

Since the clock are already prepared since probe() and unprepared in
remove(), use simple clk_enable()/clk_disable() calls to enable and
disable the clock on runtime suspend and resume, to avoid hitting the
prepare_lock mutex.

Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Fixes: 4e7bca6fc07b ("i2c: i2c-stm32f7: add PM Runtime support")
Cc: <stable@vger.kernel.org> # v5.0+
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

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i2c: stm32f7: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_time

i2c: stm32f7: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_timeout() causing patterns like:

timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

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i2c: stm32f7: add support for stm32mp25 soc

The stm32mp25 has only a single interrupt line used for both
events and errors. In order to cope with that, reorganise the
error handling code so that it

i2c: stm32f7: add support for stm32mp25 soc

The stm32mp25 has only a single interrupt line used for both
events and errors. In order to cope with that, reorganise the
error handling code so that it can be called either from the
common handler (used in case of SoC having only a single IT line)
and the error handler for others.
The CR1 register also embeds a new FMP bit, necessary when running
at Fast Mode Plus frequency. This bit should be used instead of
the SYSCFG bit used on other platforms.
Add a new compatible to distinguish between the SoCs and two
boolean within the setup structure in order to know if the
platform has a single/multiple IT lines and if the FMP bit
within CR1 is available or not.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: perform I2C_ISR read once at beginning of event isr

Move readl_relaxed of I2C_ISR register at beginning of event isr
so that it done once for both master & slave handling.

Signed-off-

i2c: stm32f7: perform I2C_ISR read once at beginning of event isr

Move readl_relaxed of I2C_ISR register at beginning of event isr
so that it done once for both master & slave handling.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: simplify status messages in case of errors

Avoid usage of __func__ when reporting an error message
since dev_err/dev_dbg are already providing enough details
to identify the source of

i2c: stm32f7: simplify status messages in case of errors

Avoid usage of __func__ when reporting an error message
since dev_err/dev_dbg are already providing enough details
to identify the source of the message.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: perform most of irq job in threaded handler

The irq handling is currently split between the irq handler
and the threaded irq handler. Some of the handling (such as
dma related stuffs)

i2c: stm32f7: perform most of irq job in threaded handler

The irq handling is currently split between the irq handler
and the threaded irq handler. Some of the handling (such as
dma related stuffs) done within the irq handler might sleep or
take some time leading to issues if the kernel is built with
realtime constraints. In order to fix that, perform an overall
rework to perform most of the job within the threaded handler
and only keep fifo access in the non threaded handler.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: use dev_err_probe upon calls of devm_request_irq

Convert error handling upon calls of devm_request_irq functions during
the probe of the driver.

Signed-off-by: Alain Volmat <alain.vol

i2c: stm32f7: use dev_err_probe upon calls of devm_request_irq

Convert error handling upon calls of devm_request_irq functions during
the probe of the driver.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: Use devm_clk_get_enabled()

Replace the pair of functions, devm_clk_get() and
clk_prepare_enable(), with a single function
devm_clk_get_enabled().

Signed-off-by: Andi Shyti <andi.shyti

i2c: stm32f7: Use devm_clk_get_enabled()

Replace the pair of functions, devm_clk_get() and
clk_prepare_enable(), with a single function
devm_clk_get_enabled().

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: add description of atomic in struct stm32f7_i2c_dev

Add missing description of the atomic boolean in struct stm32f7_i2c_dev.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Sig

i2c: stm32f7: add description of atomic in struct stm32f7_i2c_dev

Add missing description of the atomic boolean in struct stm32f7_i2c_dev.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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

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 comma

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

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 <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: Add atomic_xfer method to driver

Add an atomic_xfer method to the driver so that it behaves correctly
when controlling a PMIC that is responsible for device shutdown.

The atomic_xfer

i2c: stm32f7: Add atomic_xfer method to driver

Add an atomic_xfer method to the driver so that it behaves correctly
when controlling a PMIC that is responsible for device shutdown.

The atomic_xfer method added is similar to the one from the i2c-mv64xxx
driver. When running an atomic_xfer a bool flag in the driver data is
set, the interrupt is not unmasked on transfer start, and the IRQ
handler is manually invoked while waiting for pending transfers to
complete.

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32: Do not check for 0 return after calling platform_get_irq()

It is not possible for platform_get_irq() to return 0. Use the
return value from platform_get_irq().

Signed-off-by: Ruan Jinji

i2c: stm32: Do not check for 0 return after calling platform_get_irq()

It is not possible for platform_get_irq() to return 0. Use the
return value from platform_get_irq().

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/20230731112755.1943630-1-ruanjinjie@huawei.com
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

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i2c: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling

i2c: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Rosin <peda@axentia.se>
Acked-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Asmaa Mnebhi <asnaa@nvidia.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Chris Pringle <chris.pringle@phabrix.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Tali Perry <tali.perry@nuvoton.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32: add support for the STM32MP13 soc

Add a new compatible for the stm32mp13. Fast Mode Plus control
register address differ from the one for STM32MP15.

Signed-off-by: Alain Volmat <alain.

i2c: stm32: add support for the STM32MP13 soc

Add a new compatible for the stm32mp13. Fast Mode Plus control
register address differ from the one for STM32MP15.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: remove noisy and imprecise log messages

The log messages talk about 'bus recovery' while it is not a bus
recovery with 9 pulses but merely a controller reset. Controller resets
are not

i2c: stm32f7: remove noisy and imprecise log messages

The log messages talk about 'bus recovery' while it is not a bus
recovery with 9 pulses but merely a controller reset. Controller resets
are not worth log messages. The 'bus busy' message should be emitted by
upper layers, a busy bus may be expected in some cases.

Signed-off-by: Wolfram Sang <wsa@kernel.org>
Reviewed-by: Alain Volmat <alain.volmat@foss.st.com>

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i2c: stm32: get rid of stm32f7_i2c_release_bus return value

Function stm32f7_i2c_release_bus is always returning 0, hence it
should be a void function. Update the function and remove the
return val

i2c: stm32: get rid of stm32f7_i2c_release_bus return value

Function stm32f7_i2c_release_bus is always returning 0, hence it
should be a void function. Update the function and remove the
return value error checking code in caller functions.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: use proper DMAENGINE API for termination

dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async. Here, we use dmaengine_terminate_sync in

i2c: stm32f7: use proper DMAENGINE API for termination

dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async. Here, we use dmaengine_terminate_sync in
i2c_xfer and i2c_smbus_xfer handlers and rely on
dmaengine_terminate_async within interrupt handlers
(transmission error cases).
dmaengine_synchronize is added within i2c_xfer and i2c_smbus_xfer handler
to finalize terminate started in interrupt handlers.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: stop dma transfer in case of NACK

In case of receiving a NACK, the dma transfer should be stopped
to avoid feeding data into the FIFO.
Also ensure to properly return the proper error c

i2c: stm32f7: stop dma transfer in case of NACK

In case of receiving a NACK, the dma transfer should be stopped
to avoid feeding data into the FIFO.
Also ensure to properly return the proper error code and avoid
waiting for the end of the dma completion in case of
error happening during the transmission.

Fixes: 7ecc8cfde553 ("i2c: i2c-stm32f7: Add DMA support")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: recover the bus on access timeout

When getting an access timeout, ensure that the bus is in a proper
state prior to returning the error.

Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add dr

i2c: stm32f7: recover the bus on access timeout

When getting an access timeout, ensure that the bus is in a proper
state prior to returning the error.

Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: flush TX FIFO upon transfer errors

While handling an error during transfer (ex: NACK), it could
happen that the driver has already written data into TXDR
before the transfer get stoppe

i2c: stm32f7: flush TX FIFO upon transfer errors

While handling an error during transfer (ex: NACK), it could
happen that the driver has already written data into TXDR
before the transfer get stopped.
This commit add TXDR Flush after end of transfer in case of error to
avoid sending a wrong data on any other slave upon next transfer.

Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: add SMBus-Alert support

Add support for the SMBus-Alert protocol to the STM32F7 that has
dedicated control and status logic.

If SMBus-Alert is used, the SMBALERT# pin must be configur

i2c: stm32f7: add SMBus-Alert support

Add support for the SMBus-Alert protocol to the STM32F7 that has
dedicated control and status logic.

If SMBus-Alert is used, the SMBALERT# pin must be configured as alternate
function for I2C Alert.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: fix reference leak when pm_runtime_get_sync fails

The PM reference count is not expected to be incremented on
return in these stm32f7_i2c_xx serious functions.

However, pm_runtime_get

i2c: stm32f7: fix reference leak when pm_runtime_get_sync fails

The PM reference count is not expected to be incremented on
return in these stm32f7_i2c_xx serious functions.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

Fixes: ea6dd25deeb5 ("i2c: stm32f7: add PM_SLEEP suspend/resume support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: avoid ifdef CONFIG_PM_SLEEP for pm callbacks

Avoid CONFIG_PM preprocessor check for pm suspend/resume
callbacks and identify the functions with __maybe_unused.

Signed-off-by: Alain Vo

i2c: stm32f7: avoid ifdef CONFIG_PM_SLEEP for pm callbacks

Avoid CONFIG_PM preprocessor check for pm suspend/resume
callbacks and identify the functions with __maybe_unused.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: Remove useless error message

Fix the following coccicheck report:

drivers/i2c/busses/i2c-stm32f7.c:2032:3-10 : platform_get_irq :
line 2032 is redundant because platform_get_irq() alr

i2c: stm32f7: Remove useless error message

Fix the following coccicheck report:

drivers/i2c/busses/i2c-stm32f7.c:2032:3-10 : platform_get_irq :
line 2032 is redundant because platform_get_irq() already prints an error

Remove dev_err() messages after platform_get_irq() failures.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Zihao Tang <tangzihao1@hisilicon.com>
Reviewed-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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i2c: stm32f7: indicate the address being accessed on errors

To help debugging issues, add the address of the slave being
accessed when getting an error.

Signed-off-by: Alain Volmat <alain.volmat@fo

i2c: stm32f7: indicate the address being accessed on errors

To help debugging issues, add the address of the slave being
accessed when getting an error.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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