The S2MPG11 PMIC is a Power Management IC for mobile applications with
buck converters, various LDOs, power meters, and additional GPIO
interfaces. It typically complements an S2MPG10 PMIC in a main/sub
configuration as the sub-PMIC.
It has 12 buck, 1 buck-boost, and 15 LDO rails. Several of these can
either be controlled via software (register writes) or via external
signals, in particular by:
* input pins connected to a main processor's:
* GPIO pins
* other pins that are e.g. firmware- or power-domain-controlled
without explicit driver intervention
* a combination of input pins and register writes.
Control via input pins allows PMIC rails to be controlled by firmware,
e.g. during standby/suspend or as part of power domain handling where
otherwise that would not be possible. Additionally toggling a pin is
faster than register writes, and it also allows the PMIC to ensure that
any necessary timing requirements between rails are respected
automatically if multiple rails are to be enabled or disabled quasi
simultaneously.
This commit implements support for all these rails and control
combination.
Note1: For an externally controlled rail, the regulator_ops provide an
empty ::enable() and no ::disable() implementations, even though Linux
can not enable the rail and one might think ::enable could be NULL.
Without ops->enable(), the regulator core will assume enabling such a
rail failed, though, and in turn never add a reference to its parent
(supplier) rail. Once a different (Linux-controlled) sibling (consumer)
rail on that same parent rail gets disabled, the parent gets disabled
(cutting power to the externally controlled rail although it should
stay on), and the system will misbehave.
Note2: While external control via input pins appears to exist on other
versions of this PMIC, there is more flexibility in this version, in
particular there is a selection of input pins to choose from for each
rail (which must therefore be configured accordingly if in use),
whereas other versions don't have this flexibility.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260122-s2mpg1x-regulators-v7-19-3b1f9831fffd@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The upcoming S2MPG11 support needs a similar, but different version of
::set_voltage_time(). For S2MPG10, the downwards and upwards ramps for
a rail are at different offsets at the same bit positions, while for
S2MPG11 the ramps are at the same offset at different bit positions.
Refactor the existing version slightly to allow reuse.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260122-s2mpg1x-regulators-v7-17-3b1f9831fffd@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The S2MPG10 PMIC is a Power Management IC for mobile applications with
buck converters, various LDOs, power meters, RTC, clock outputs, and
additional GPIO interfaces.
It has 10 buck and 31 LDO rails. Several of these can either be
controlled via software (register writes) or via external signals, in
particular by:
* one out of several input pins connected to a main processor's:
* GPIO pins
* other pins that are e.g. firmware- or power-domain-controlled
without explicit driver intervention
* a combination of input pins and register writes.
Control via input pins allows PMIC rails to be controlled by firmware,
e.g. during standby/suspend, or as part of power domain handling where
otherwise that would not be possible. Additionally toggling a pin is
faster than register writes, and it also allows the PMIC to ensure that
any necessary timing requirements between rails are respected
automatically if multiple rails are to be enabled or disabled quasi
simultaneously.
This commit implements support for all these rails and control
combinations.
Additional data needs to be stored for each regulator, e.g. the input
pin for external control, or a rail-specific ramp-rate for when
enabling a buck-rail. Therefore, probe() is updated slightly to make
that possible.
Note1: For an externally controlled rail, the regulator_ops provide an
empty ::enable() and no ::disable() implementations, even though Linux
can not enable the rail and one might think ::enable could be NULL.
Without ops->enable(), the regulator core will assume enabling such a
rail failed, though, and in turn never add a reference to its parent
(supplier) rail. Once a different (Linux-controlled) sibling (consumer)
rail on that same parent rail gets disabled, the parent gets disabled
(cutting power to the externally controlled rail although it should
stay on), and the system will misbehave.
Note2: While external control via input pins appears to exist on other
versions of this PMIC, there is more flexibility in this version, in
particular there is a selection of input pins to choose from for each
rail (which must therefore be configured accordingly if in use),
whereas other versions don't have this flexibility.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260122-s2mpg1x-regulators-v7-16-3b1f9831fffd@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Refactor s2mps14_pmic_enable_ext_control() and s2mps11_of_parse_cb()
slightly as a preparation for adding S2MPG10 and S2MPG11 support, as
both of those PMICs also support control of rails via GPIOs.
This also includes the following to avoid further updates in follow-up
commits:
* On S2MPG10 and S2MPG11, external rail control can be via GPIO or via
non-GPIO signals, hence passing a GPIO is allowed to be optional.
This avoids inappropriate verbose driver messages.
* Prepare to allow use of standard DT property name 'enable-gpios' for
newer platforms instead of vendor-specific 'samsung,ext-control'.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260122-s2mpg1x-regulators-v7-15-3b1f9831fffd@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
For the upcoming S2MPG10 and S2MPG11 support, we need to be able to
parse -supply properties in the PMIC's DT node.
This currently doesn't work, because the code here currently points the
regulator core at each individual regulator sub-node, and therefore the
regulator core is unable to find the -supply properties.
Update the code to simply let the regulator core handle all the parsing
by adding the ::of_match and ::regulators_node members to all existing
regulator descriptions, by adding ::of_parse_cb() to those
regulators which support the vendor-specific samsung,ext-control-gpios
to parse it (S2MPS14), and by dropping the explicit call to
of_regulator_match().
Configuring the PMIC to respect the external control GPIOs via
s2mps14_pmic_enable_ext_control() is left outside ::of_parse_cb()
because the regulator core ignores errors other than -EPROBE_DEFER from
that callback, while the code currently fails probe on register write
errors and I believe it should stay that way.
The driver can now avoid the devm_gpiod_unhinge() dance due to
simpler error handling of GPIO descriptor acquisition.
This change also has the advantage of reducing runtime memory
consumption by quite a bit as the driver doesn't need to allocate a
'struct of_regulator_match' and a 'struct gpio_desc *' for each
regulator for all PMICs as the regulator core does that. This saves
40+8 bytes on arm64 for each individual regulator on all supported
PMICs (even on non-S2MPS14 due to currently unnecessarily allocating
the extra memory unconditionally). With the upcoming S2MPG10 and
S2MPG11 support, this amounts to 1640+328 and 1120+224 bytes
respectively.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260122-s2mpg1x-regulators-v7-14-3b1f9831fffd@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Probing of regulators can be a slow operation and can contribute to
slower boot times. This is especially true if a regulator is turned on
at probe time (with regulator-boot-on or regulator-always-on) and the
regulator requires delays (off-on-time, ramp time, etc).
While the overall kernel is not ready to switch to async probe by
default, as per the discussion on the mailing lists [1] it is believed
that the regulator subsystem is in good shape and we can move
regulator drivers over wholesale. There is no way to just magically
opt in all regulators (regulators are just normal drivers like
platform_driver), so we set PROBE_PREFER_ASYNCHRONOUS for all
regulators found in 'drivers/regulator' individually.
Given the number of drivers touched and the impossibility to test this
ahead of time, it wouldn't be shocking at all if this caused a
regression for someone. If there is a regression caused by this patch,
it's likely to be one of the cases talked about in [1]. As a "quick
fix", drivers involved in the regression could be fixed by changing
them to PROBE_FORCE_SYNCHRONOUS. That being said, the correct fix
would be to directly fix the problem that caused the issue with async
probe.
The approach here follows a similar approach that was used for the mmc
subsystem several years ago [2]. In fact, I ran nearly the same python
script to auto-generate the changes. The only thing I changed was to
search for "i2c_driver", "spmi_driver", and "spi_driver" in addition
to "platform_driver".
[1] https://lore.kernel.org/r/06db017f-e985-4434-8d1d-02ca2100cca0@sirena.org.uk
[2] https://lore.kernel.org/r/20200903232441.2694866-1-dianders@chromium.org/
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230316125351.1.I2a4677392a38db5758dee0788b2cea5872562a82@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix up inconsistent usage of upper and lowercase letters in "Samsung"
name.
"SAMSUNG" is not an abbreviation but a regular trademarked name.
Therefore it should be written with lowercase letters starting with
capital letter.
Although advertisement materials usually use uppercase "SAMSUNG", the
lowercase version is used in all legal aspects (e.g. on Wikipedia and in
privacy/legal statements on
https://www.samsung.com/semiconductor/privacy-global/).
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200103171131.9900-20-krzk@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver was registering buck regulators with unsupported range of
voltages for S2MPS11 devices. Basically it assumed that all 256 values
are possible for a single 8-bit I2C register controlling buck's voltage.
This is not true, as datasheet describes subset of these which can be
used.
For example for buck[12346] the minimum voltage is 650 mV which
corresponds to register value of 0x8. The driver was however
registering regulator starting at 600 mV, so for a step of 6.25 mV this
gave the same result. However this allowed to try to configure
regulators to unsupported values.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
On S2MPS11 device, the buck7 and buck8 regulator voltages start at 750
mV, not 600 mV. Using wrong minimal value caused shifting of these
regulator values by 150 mV (e.g. buck7 usually configured to v1.35 V was
reported as 1.2 V).
On most of the boards these regulators are left in default state so this
was only affecting reported voltage. However if any driver wanted to
change them, then effectively it would set voltage 150 mV higher than
intended.
Cc: <stable@vger.kernel.org>
Fixes: cb74685ecb ("regulator: s2mps11: Add samsung s2mps11 regulator driver")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In case the requested gpio property is not found in the device tree, some
callers of gpiod_get_from_of_node() expect a return value of NULL, others
expect -ENOENT.
In particular devm_fwnode_get_index_gpiod_from_child() expects -ENOENT.
Currently it gets a NULL, which breaks the loop that tries all
gpio_suffixes. The result is that a gpio property is not found, even
though it is there.
This patch changes gpiod_get_from_of_node() to return -ENOENT instead
of NULL when the requested gpio property is not found in the device
tree. Additionally it modifies all calling functions to properly
evaluate the return value.
Another approach would be to leave the return value of
gpiod_get_from_of_node() as is and fix the bug in
devm_fwnode_get_index_gpiod_from_child(). Other callers would still need
to be reworked. The effort would be the same as with the chosen solution.
Signed-off-by: Georg Waibel <georg.waibel@sensor-technik.de>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver supported turning off regulators in suspend only for S2MPS14
device. However this makes also sense for S2MPS11 and can reduce the
power consumption during suspend to RAM.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Store the regulator ID instead of calling rdev_get_id() every time.
This makes code slightly easier to read as shorter 'rdev_id' variable is
used instead of full call. This can also speed things up by reducing
number of calls, although effect was not measured.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
If devm_gpiod_get_from_of_node() call returns ERR_PTR, it is assigned
into an array of GPIO descriptors and used later because such error is
not treated as critical thus it is not propagated back to the probe
function.
All code later expects that such GPIO descriptor is either a NULL or
proper value. This later might lead to dereference of ERR_PTR.
Only devices with S2MPS14 flavor are affected (other do not control
regulators with GPIOs).
Fixes: 1c984942f0 ("regulator: s2mps11: Pass descriptor instead of GPIO number")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
LDO35 uses 25 mV step, not 50 mV. Bucks 7 and 8 use 12.5 mV step
instead of 6.25 mV. Wrong step caused over-voltage (LDO35) or
under-voltage (buck7 and 8) if regulators were used (e.g. on Exynos5420
Arndale Octa board).
Cc: <stable@vger.kernel.org>
Fixes: cb74685ecb ("regulator: s2mps11: Add samsung s2mps11 regulator driver")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The GPIO descriptors used by the S2MPS11 driver are retrieved
during probe() and it is really helpful to have those under
devres management because of all the errorpaths in the
intialization.
Using the new dev_gpiod_unhinge() call we can remove the
devres management of the descriptor right before handing
it over to the regulators core.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
GPIO descriptor array must be zero initialized to ensure that core will
properly handle also the case when no external GPIO pin is defined.
Fixes: 1c984942f0 ("regulator: s2mps11: Pass descriptor instead of GPIO number")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Instead of passing a global GPIO number for the enable GPIO, pass
a descriptor looked up with the standard devm_gpiod_get_optional()
call.
This regulator supports passing platform data, but enable/sleep
regulators are looked up from the device tree exclusively, so
we can need not touch other files.
Tested on Odroid XU3 (with s2mps11 although not using any GPIOs
for regulators, so at least default paths are not broken).
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace GPL v2.0+ license statements with SPDX license
identifiers.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Static struct regulator_ops is not modified so can be made const for
code safeness.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch fixes some of the LDOs and BUCKs voltage range as per
user manual of s2mps15 (REV0.4).
Fixes: 51af206758 ("regulator: s2mps11: Add support for S2MPS15 regulators")
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
Driver did not provide default value for ramp delay for LDOs which lead
to warning in dmesg, e.g. on Odroid XU4:
[ 1.486076] vdd_ldo9: ramp_delay not set
[ 1.506875] vddq_mmc2: ramp_delay not set
[ 1.523766] vdd_ldo15: ramp_delay not set
[ 1.544702] vdd_sd: ramp_delay not set
The datasheet for all the S2MPS1x family is inconsistent here and does
not specify unambiguously the value of ramp delay for LDO. It mentions
30 mV/us in one timing diagram but then omits it completely in LDO
regulator characteristics table (it is specified for bucks).
However the vendor kernels for Galaxy S5 and Odroid XU3 use values of 12
mV/us or 24 mV/us.
Without the ramp delay value the consumers do not wait for voltage
settle after changing it. Although the proper value of ramp delay for
LDOs is unknown, it seems safer to use at least some value from
reference kernel than to leave it unset.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver's init and exit function don't do anything besides registering
and unregistering the platform driver, so the module_platform_driver()
macro could just be used instead of having separate functions.
Currently the macro is not being used because the driver is initialized at
subsys init call level but this isn't necessary since consumer devices are
defined in the DT as dependencies so there's no need for init calls order.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The buck9 regulator of S2MPS11 PMIC had incorrect vsel_mask (0xff
instead of 0x1f) thus reading entire register as buck9's voltage. This
effectively caused regulator core to interpret values as higher voltages
than they were and then to set real voltage much lower than intended.
The buck9 provides power to other regulators, including LDO13
and LDO19 which supply the MMC2 (SD card). On Odroid XU3/XU4 the lower
voltage caused SD card detection errors on Odroid XU3/XU4:
mmc1: card never left busy state
mmc1: error -110 whilst initialising SD card
During driver probe the regulator core was checking whether initial
voltage matches the constraints. With incorrect vsel_mask of 0xff and
default value of 0x50, the core interpreted this as 5 V which is outside
of constraints (3-3.775 V). Then the regulator core was adjusting the
voltage to match the constraints. With incorrect vsel_mask this new
voltage mapped to a vere low voltage in the driver.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
Following BUILD_BUG_ON using a variable fails for some of the compilers
and optimization levels (reported for gcc 4.9):
var = ARRAY_SIZE(s2mps15_regulators);
BUILD_BUG_ON(S2MPS_REGULATOR_MAX < var);
Fix this by using ARRAY_SIZE directly.
Additionally add missing BUILD_BUG_ON check for S2MPS15 device (the
check ensures that internal arrays are big enough to hold data for all
of regulators on all devices).
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently S2MPSXX multifunction device is named as *-pmic,
and these MFDs also supports regulator as a one of its MFD cell which
has the same name, because current name is confusing and we want to
sort it out.
We did discussed different approaches about how the MFD and it
cells need to be named here [1].
Based in the discussion this patch rename MFD regulator name as
*-regulator instead of current *-pmic.
This patch also changes the corresponding entries in the regulator driver
to keep git-bisect happy.
[1]-> https://lkml.org/lkml/2015/10/28/417
Suggested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The S2MPS15 PMIC is similar in functionality to S2MPS11/14 PMIC. It contains
27 LDO and 10 Buck regulators and allows programming these regulators via a
I2C interface. This patch adds initial support for LDO/Buck regulators of
S2MPS15 PMIC.
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Status of enabling suspend mode for regulator was stored in bitmap-like
long integer.
However since adding support for S2MPU02 the number of regulators
exceeded 32 so on devices with more than 32 regulators (S2MPU02 and
S2MPS13) overflow happens when shifting the bit. This could lead to
enabling suspend mode for completely different regulator than intended
or to switching different regulator to other mode (e.g. from always
enabled to controlled by PWRHOLD pin). Both cases could result in larger
energy usage and issues when suspending to RAM.
Fixes: 00e2573d2c ("regulator: s2mps11: Add support S2MPU02 regulator device")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
Remove unneeded semicolons after the switch statement to satisfy
coccicheck.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds missing registers('BUCK7_SW' & 'LDO29_CTRL'). Since BUCK7 has
1 more register (BUCK7_SW) than others, register offset should
be added one more for which has bigger address than BUCK7 registers.
Fixes: 76b9840b24ae04(regulator: s2mps11: Add support S2MPS13 regulator device)
Signed-off-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
Pull one regulator fix from Mark Brown:
"One fix here, a fix for the voltage mapping on one of the s2mps11
regulators which broke systems using it including apparently the
Gear 2 smartwatches"
* tag 'regulator-v3.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: s2mps11: Fix dw_mmc failure on Gear 2
Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.
Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev_<level>_once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
