regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-

regmap: Add regmap_read_bypassed()

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

regmap: prevent noinc writes from clobbering cache

[ Upstream commit 984a4afdc87a1fc226fd657b1cd8255c13d3fc1a ]

Currently, noinc writes are cached as if they were standard incrementing
writes, over

regmap: prevent noinc writes from clobbering cache

[ Upstream commit 984a4afdc87a1fc226fd657b1cd8255c13d3fc1a ]

Currently, noinc writes are cached as if they were standard incrementing
writes, overwriting unrelated register values in the cache. Instead, we
want to cache the last value written to the register, as is done in the
accelerated noinc handler (regmap_noinc_readwrite).

Fixes: cdf6b11daa77 ("regmap: Add regmap_noinc_write API")
Signed-off-by: Ben Wolsieffer <ben.wolsieffer@hefring.com>
Link: https://lore.kernel.org/r/20231101142926.2722603-2-ben.wolsieffer@hefring.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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regmap: fix NULL deref on lookup

Not all regmaps have a name so make sure to check for that to avoid
dereferencing a NULL pointer when dev_get_regmap() is used to lookup a
named regmap.

Fixes: e848

regmap: fix NULL deref on lookup

Not all regmaps have a name so make sure to check for that to avoid
dereferencing a NULL pointer when dev_get_regmap() is used to lookup a
named regmap.

Fixes: e84861fec32d ("regmap: dev_get_regmap_match(): fix string comparison")
Cc: stable@vger.kernel.org # 5.8
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20231006082104.16707-1-johan+linaro@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Remove dynamic allocation warnings for rbtree and maple

Thanks to Dan and Guenter's very prompt updates of the rbtree and maple
caches to support GPF_ATOMIC allocations and since the update

regmap: Remove dynamic allocation warnings for rbtree and maple

Thanks to Dan and Guenter's very prompt updates of the rbtree and maple
caches to support GPF_ATOMIC allocations and since the update shook out
a bunch of users at least some of whom have been suitably careful about
ensuring that the cache is prepoulated so there are no dynamic
allocations after init let's revert the warnings.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230721-regmap-enable-kmalloc-v1-1-f78287e794d3@kernel.org

show more ...

regmap: Reject fast_io regmap configurations with RBTREE and MAPLE caches

REGCACHE_RBTREE and REGCACHE_MAPLE dynamically allocate memory for regmap
operations. This is incompatible with spinlock bas

regmap: Reject fast_io regmap configurations with RBTREE and MAPLE caches

REGCACHE_RBTREE and REGCACHE_MAPLE dynamically allocate memory for regmap
operations. This is incompatible with spinlock based locking which is used
for fast_io operations. Reject affected configurations.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230720032848.1306349-2-linux@roeck-us.net
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Drop initial version of maximum transfer length fixes

When problems were noticed with the register address not being taken
into account when limiting raw transfers with I2C devices we fixed

regmap: Drop initial version of maximum transfer length fixes

When problems were noticed with the register address not being taken
into account when limiting raw transfers with I2C devices we fixed this
in the core. Unfortunately it has subsequently been realised that a lot
of buses were relying on the prior behaviour, partly due to unclear
documentation not making it obvious what was intended in the core. This
is all more involved to fix than is sensible for a fix commit so let's
just drop the original fixes, a separate commit will fix the originally
observed problem in an I2C specific way

Fixes: 3981514180c9 ("regmap: Account for register length when chunking")
Fixes: c8e796895e23 ("regmap: spi-avmm: Fix regmap_bus max_raw_write")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20230712-regmap-max-transfer-v1-1-80e2aed22e83@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Revert "add 64-bit mode support" and Co.

With unsigned int type we never ever can pass 64-bit value.
Remove never properly worked code.

Note, there are no users in kernel for this size of r

regmap: Revert "add 64-bit mode support" and Co.

With unsigned int type we never ever can pass 64-bit value.
Remove never properly worked code.

Note, there are no users in kernel for this size of register
offsets or data.

This reverts commit afcc00b91f1865f6d0bbdb687dd642ce8a3c3c9e.

Also revert other 64-bit code excerpts in the regmap implementation
that had been induced by the false impression made by the above
mentioned change that there is a support of that data size.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230622183613.58762-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Drop early readability check

We have some drivers that have a use case for cached write only
registers, doing read/modify/writes on read only registers in order to
work more easily with bitf

regmap: Drop early readability check

We have some drivers that have a use case for cached write only
registers, doing read/modify/writes on read only registers in order to
work more easily with bitfields. Go back to trying the cache before we
check if we can read from the device.

Fixes: eab5abdeb79f0 ("regmap: Check for register readability before checking cache during read")
Reported-by: Konrad Dybcio <konradybcio@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230615-regmap-drop-early-readability-v1-1-8135094362de@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Check for register readability before checking cache during read

Ensure that we don't return a spurious cache hit for unreadable registers
(eg, with the flat cache which doesn't understand s

regmap: Check for register readability before checking cache during read

Ensure that we don't return a spurious cache hit for unreadable registers
(eg, with the flat cache which doesn't understand sparseness) by checking
for readability before we do a cache lookup.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230613-b4-regmap-check-readability-before-cache-v1-1-b144c0b01ed9@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Add debugfs file for forcing field writes

`_regmap_update_bits()` checks if the current register value differs
from the new value, and only writes to the register if they differ. When
testin

regmap: Add debugfs file for forcing field writes

`_regmap_update_bits()` checks if the current register value differs
from the new value, and only writes to the register if they differ. When
testing hardware drivers, it might be desirable to always force a
register write, for example when writing to a `regmap_field`. This
enables and simplifies testing and verification of the hardware
interaction. For example, when using a hardware mock/simulation model,
one can then more easily verify that the driver makes the correct
expected register writes during certain events.

Add a bool variable `force_write_field` and a corresponding debugfs
entry to enable this. Since this feature could interfere with driver
operation, guard it with a macro.

Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Link: https://lore.kernel.org/r/pnd1qifa7sj.fsf@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Add missing cache_only checks

The current behaviour around cache_only is slightly inconsistent,
most paths will only check cache_only if cache_bypass is false,
and will return -EBUSY if a re

regmap: Add missing cache_only checks

The current behaviour around cache_only is slightly inconsistent,
most paths will only check cache_only if cache_bypass is false,
and will return -EBUSY if a read attempts to go to the hardware
whilst cache_only is true. However, a couple of paths will not check
cache_only at all. The most notable of these being regmap_raw_read
which will check cache_only in the case it processes the transaction
one register at a time, but not in the case it handles them as a
block. In the typical case a device has been put into cache_only
whilst powered down this can cause physical reads to happen whilst the
device is unavailable.

Add a check in regmap_raw_read and move the check in regmap_noinc_read,
adding a check for cache_bypass, such that all paths are covered and
consistent.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230601101036.1499612-2-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Account for register length when chunking

Currently, when regmap_raw_write() splits the data, it uses the
max_raw_write value defined for the bus. For any bus that includes
the target regis

regmap: Account for register length when chunking

Currently, when regmap_raw_write() splits the data, it uses the
max_raw_write value defined for the bus. For any bus that includes
the target register address in the max_raw_write value, the chunked
transmission will always exceed the maximum transmission length.
To avoid this problem, subtract the length of the register and the
padding from the maximum transmission.

Signed-off-by: Jim Wylder <jwylder@google.com
Link: https://lore.kernel.org/r/20230517152444.3690870-2-jwylder@google.com
Signed-off-by: Mark Brown <broonie@kernel.org

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regmap: allow upshifting register addresses before performing operations

Similar to the existing reg_downshift mechanism, that is used to
translate register addresses on busses that have a smaller a

regmap: allow upshifting register addresses before performing operations

Similar to the existing reg_downshift mechanism, that is used to
translate register addresses on busses that have a smaller address
stride, it's also possible to want to upshift register addresses.

Such a case was encountered when network PHYs and PCS that usually sit
on a MDIO bus (16-bits register with a stride of 1) are integrated
directly as memory-mapped devices. Here, the same register layout
defined in 802.3 is used, but the register now have a larger stride.

Introduce a mechanism to also allow upshifting register addresses.
Re-purpose reg_downshift into a more generic, signed reg_shift, whose
sign indicates the direction of the shift. To avoid confusion, also
introduce macros to explicitly indicate if we want to downshift or
upshift.

For bisectability, change any use of reg_downshift to use reg_shift.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Colin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20230407152604.105467-1-maxime.chevallier@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Support paging for buses with reg_read()/reg_write()

We don't currently support paging for regmaps where the I/O happens through
bus provided reg_read() and reg_write() operatons, we simply

regmap: Support paging for buses with reg_read()/reg_write()

We don't currently support paging for regmaps where the I/O happens through
bus provided reg_read() and reg_write() operatons, we simply ignore the
range since nothing is wired up properly. Wire things up.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230324-regmap-reg-read-write-page-v1-1-1fbc0dac67ae@kernel.org

show more ...

regmap: add a helper to translate the register address

Register addresses passed to regmap operations can be offset with
regmap.reg_base and downshifted with regmap.reg_downshift.

Add a helper to a

regmap: add a helper to translate the register address

Register addresses passed to regmap operations can be offset with
regmap.reg_base and downshifted with regmap.reg_downshift.

Add a helper to apply both these operations and return the translated
address, that we can then use to perform the actual register operation
ont the underlying bus.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://lore.kernel.org/r/20230324093644.464704-2-maxime.chevallier@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: apply reg_base and reg_downshift for single register ops

reg_base and reg_downshift currently don't have any effect if used with
a regmap_bus or regmap_config which only offers single regist

regmap: apply reg_base and reg_downshift for single register ops

reg_base and reg_downshift currently don't have any effect if used with
a regmap_bus or regmap_config which only offers single register
operations (ie. reg_read, reg_write and optionally reg_update_bits).

Fix that and take them into account also for regmap_bus with only
reg_read and read_write operations by applying reg_base and
reg_downshift in _regmap_bus_reg_write, _regmap_bus_reg_read.

Also apply reg_base and reg_downshift in _regmap_update_bits, but only
in case the operation is carried out with a reg_update_bits call
defined in either regmap_bus or regmap_config.

Fixes: 0074f3f2b1e43d ("regmap: allow a defined reg_base to be added to every address")
Fixes: 86fc59ef818beb ("regmap: add configurable downshift for addresses")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Tested-by: Colin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/Y9clyVS3tQEHlUhA@makrotopia.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: add regmap_might_sleep()

With the dawn of MMIO gpio-regmap users, it is desirable to let
gpio-regmap ask the regmap if it might sleep during an access so
it can pass that information to gpio

regmap: add regmap_might_sleep()

With the dawn of MMIO gpio-regmap users, it is desirable to let
gpio-regmap ask the regmap if it might sleep during an access so
it can pass that information to gpiochip. Add a new regmap_might_sleep()
to query the regmap.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20221121150843.1562603-1-michael@walle.cc
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: check right noinc bounds in debug print

We were using the wrong bound in the debug prints: this
needs to be the number of elements, not the number of bytes,
since we're indexing into an elem

regmap: check right noinc bounds in debug print

We were using the wrong bound in the debug prints: this
needs to be the number of elements, not the number of bytes,
since we're indexing into an element-size typed array.

Fixes: c20cc099b30a ("regmap: Support accelerated noinc operations")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220823135700.265019-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: introduce value tracing for regmap bulk operations

Currently, only one-register io operations support tracepoints with
value logging. For the regmap bulk operations developer can view
hw_sta

regmap: introduce value tracing for regmap bulk operations

Currently, only one-register io operations support tracepoints with
value logging. For the regmap bulk operations developer can view
hw_start/hw_done tracepoints with starting reg number and registers
count to be reading or writing. This patch injects tracepoints with
dumping registers values in the hex format to regmap bulk reading
and writing.

Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Link: https://lore.kernel.org/r/20220816181451.5628-1-ddrokosov@sberdevices.ru
Signed-off-by: Mark Brown <broonie@kernel.org>

show more ...