This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
When creating the regulator object, associated with a consumer device,
the supply_name is string formatted into a statically sized buffer on
the stack, then strdup()'ed onto the heap.
Not only is the dance on the stack unnecessary, but when the device's
name is long we might not fit the constructed supply_name in the fixed
64 byte buffer on the stack.
One such case can be seen on the Qualcomm Rb3Gen2 board, where we find a
PCIe controller, with a PCIe switch, with a USB controller, with a USB
hub, consuming a regulator. In this example the dev->kobj.name itself is
62 characters long.
Drop the temporary buffer on the stack and kasprintf() the string
directly on the heap, both to simplify the code, and to remove the
length limitation.
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Link: https://patch.msgid.link/20260211-regulator-supply-name-length-v1-1-3875541c1576@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 98e48cd928 ("regulator: core: resolve supply for
boot-on/always-on regulators"), the regulator core returns
-EPROBE_DEFER if a supply can not be resolved at regulator_register()
time due to set_machine_constraints() requiring that supply (e.g.
because of always-on or boot-on).
In some hardware designs, multiple PMICs are used where individual
rails of each act as supplies for rails of the other, and vice-versa.
In such a design no PMIC driver can probe when registering one top-
level regulator device (as is common practice for almost all regulator
drivers in Linux) since that commit. Supplies are only considered when
their driver has fully bound, but because in a design like the above
two drivers / devices depend on each other, neither will have fully
bound while the other probes. The Google Pixel 6 and 6 Pro (oriole and
raven) are examples of such a design.
One way to make this work would be to register each rail as an
individual device, rather than just one top-level regulator device.
Then, fw-devlink and Linux' driver core could do their usual handling
of deferred device probe as each rail would be probed individually.
This approach was dismissed in [1] as each regulator driver would have
to take care of this itself.
Alternatively, we can change the regulator core to not fail
regulator_register() if a rail's required supply can not be resolved
while keeping the intended change from above mentioned commit, and
instead retry whenever a new rail is registered. This commit implements
such an approach:
If set_machine_constraints() requests probe deferral,
regulator_register() still succeeds and we retry setting
constraints as part of regulator_resolve_supply().
We still do not enable the regulator or allow consumers to use it
until constraints have been set (including resolution of the
supply) to prevent enabling of a regulator before its supply.
With this change, we keep track of regulators with missing required
supplies and can therefore try to resolve them again and try to set
the constraints again once more regulators become available.
Care has to be taken to not allow consumers to use regulators that
haven't had their constraints set yet. regulator_get() ensures that
and now returns -EPROBE_DEFER in that case.
The implementation is straight-forward, thanks to our newly introduced
regulator-bus. Locking in regulator_resolve_supply() has to be done
carefully, as a combination of regulator_(un)lock_two() and
regulator_(un)lock_dependent() is needed. The reason is that
set_machine_constraints() might call regulator_enable() which needs
rdev and all its dependents locked, but everything else requires to
only have rdev and its supply locked.
Link: https://lore.kernel.org/all/aRn_-o-vie_QoDXD@sirena.co.uk/ [1]
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-8-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
When a regulator A and its supply B are provided by different devices,
the driver implementing B might be last to probe (with A still
pending resolution of its supply B). While we try to resolve all
pending supplies for all regulators (including A) during
regulator_register() of B via regulator_register_resolve_supply(),
supply resolution will still not work for A as the driver for B hasn't
finished binding to the PMIC device corresponding to B at that stage
yet. The regulator core explicitly only allows supplies from other
devices to be used once the relevant driver has fully bound, mainly to
avoid having to deal with cases where B itself might -EPROBE_DEFER.
In this case, A's supply will only be resolved as part of the core's
regulator_init_complete_work_function(), which currently is scheduled
to run after 30s. This was added as a work-around in
commit 3827b64dba ("regulator: core: Resolve supplies before
disabling unused regulators") to cover this situation.
There are two problems with that approach:
* it potentially runs long after all our consumers have probed
* an upcoming change will allow regulator_register() to complete
successfully even when required supplies (e.g. due to always-on or
boot-on) are missing at register time, deferring full configuration
of the regulator (and usability by consumers, i.e. usually consumer
probe) until the supply becomes available.
Resolving supplies in the late work func can therefore make it
impossible for consumers to probe at all, as the driver core will not
know to reprobe consumers when supplies have resolved.
We could schedule an earlier work to try to resolve supplies sooner,
but that'd be racy as consumers of A might try to probe before A's
supply gets fully resolved via this extra work.
Instead, add a very simple regulator bus and add a dummy device with a
corresponding driver to it for each regulator that is missing its
supply during regulator_register(). This way, the driver core will call
our bus' probe whenever a new (regulator) device was successfully
bound, allowing us to retry resolving the supply during (our bus) probe
and to bind this dummy device if successful. In turn this means the
driver core will see a newly bound device and retry probing of all
pending consumers, if any.
With that in place, we can avoid walking the full list of all known
regulators to try resolve missing supplies during regulator_register(),
as the driver core will invoke the bus probe for regulators that are
still pending their supplies. We can also drop the code trying to
resolve supplies one last time before unused regulators get disabled,
as all supplies should have resolved at that point in time, and if they
haven't then there's no point in trying again, as the outcome won't
change.
Note: We can not reuse the existing struct device created for each
rail, as a device can not be part of a class and a bus simultaneously.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-7-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Receiving and forwarding critical supply events seems like they're
important information and we shouldn't ignore errors occurring during
registration for such events.
With this change the supply is unset on event registration failure,
allowing us to potentially retry another time.
Fixes: 433e294c3c ("regulator: core: forward undervoltage events downstream by default")
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-6-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 98e48cd928 ("regulator: core: resolve supply for
boot-on/always-on regulators") we require that a regulator's supply has
been resolved before enabling the regulator. Furthermore,
regulator_get() also fails if the supply hasn't been resolved yet
(preventing consumers from enabling a regulator without its supply
known). In combination this means that regulator_resolve_supply() now
always runs before the regulator has been enabled via
set_machine_constraints().
The code here was meant to run after enabling the regulator in case the
supply hadn't been resolved at that time and can therefore never
execute anymore since that commit.
Remove it.
No functional change intended.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-5-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
For always-on and boot-on regulators, regulator_register() is currently
trying to anticipate the requirement to resolve a supply early.
Unfortunately, this code executes too early, before we have potentially
updated the regulator's always_on constraint as part of
set_machine_constraints(), causing it to miss cases.
Rather than trying to hack it more, just defer to the outcome of
set_machine_constraints(). The latter returns early (without doing any
regulator initialisation) with -EPROBE_DEFER as of commit 'regulator:
core: move supply check earlier in set_machine_constraints()' and is
therefore safe to call multiple times to determine if supplies need to
be resolved early.
Commit 8a866d527a ("regulator: core: Resolve supply name earlier to
prevent double-init") (later updated by
commit 520fb17821 ("regulator: core: Fix regulator supply
registration with sysfs")) added these tests originally to avoid
calling set_machine_constraints() multiple times to try to avoid
voltage glitches due to all the regulator initialisation happening each
time. This isn't an issue anymore as per above.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-4-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 98e48cd928 ("regulator: core: resolve supply for
boot-on/always-on regulators"), set_machine_constraints() can return
-EPROBE_DEFER very late, after it has done a lot of work and
configuration of the regulator.
This means that configuration will happen multiple times for no
benefit in that case. Furthermore, this can lead to timing-dependent
voltage glitches as mentioned e.g. in commit 8a866d527a ("regulator:
core: Resolve supply name earlier to prevent double-init").
We can know that it's going to fail very early, in particular before
going through the complete regulator configuration by moving some code
around a little.
Do so to avoid re-configuring the regulator multiple times, also
avoiding the voltage glitches if we can.
Fixes: 98e48cd928 ("regulator: core: resolve supply for boot-on/always-on regulators")
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-3-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
If late enabling of a supply regulator fails in
regulator_resolve_supply(), the code currently triggers a lockdep
warning:
WARNING: drivers/regulator/core.c:2649 at _regulator_put+0x80/0xa0, CPU#6: kworker/u32:4/596
...
Call trace:
_regulator_put+0x80/0xa0 (P)
regulator_resolve_supply+0x7cc/0xbe0
regulator_register_resolve_supply+0x28/0xb8
as the regulator_list_mutex must be held when calling _regulator_put().
To solve this, simply switch to using regulator_put().
While at it, we should also make sure that no concurrent access happens
to our rdev while we clear out the supply pointer. Add appropriate
locking to ensure that.
While the code in question will be removed altogether in a follow-up
commit, I believe it is still beneficial to have this corrected before
removal for future reference.
Fixes: 36a1f1b6dd ("regulator: core: Fix memory leak in regulator_resolve_supply()")
Fixes: 8e5356a736 ("regulator: core: Clear the supply pointer if enabling fails")
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-2-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
1)
In print_constraints_debug(), the power budget is printed as:
lldo2: 450 <--> 1300 mV at 900 mV 2147483647 mW budge, enabled
(note the missing t in budget). This is because there is a --count just
below the call to scnprintf(), to make space for the comma. All similar
calls to scnprintf() above add an extra space to the format string to
allow for that, but this one doesn't, so the last character t is
stripped instead. Update the format string to fix the message.
2)
Add the name of the supply to the failure message printed when the
supply can not be resolved when debug messages are enabled to help with
debug.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260109-regulators-defer-v2-1-1a25dc968e60@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
regulator_supply_alias_list was accessed without any locking in
regulator_supply_alias(), regulator_register_supply_alias(), and
regulator_unregister_supply_alias(). Concurrent registration,
unregistration and lookups can race, leading to:
1 use-after-free if an alias entry is removed while being read,
2 duplicate entries when two threads register the same alias,
3 inconsistent alias mappings observed by consumers.
Protect all traversals, insertions and deletions on
regulator_supply_alias_list with the existing regulator_list_mutex.
Fixes: a06ccd9c37 ("regulator: core: Add ability to create a lookup alias for supply")
Signed-off-by: sparkhuang <huangshaobo3@xiaomi.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20251127025716.5440-1-huangshaobo3@xiaomi.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from Bartosz Golaszewski <brgl@bgdev.pl>:
Problem statement: GPIOs are implemented as a strictly exclusive
resource in the kernel but there are lots of platforms on which single
pin is shared by multiple devices which don't communicate so need some
way of properly sharing access to a GPIO. What we have now is the
GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which was introduced as a hack and
doesn't do any locking or arbitration of access - it literally just hand
the same GPIO descriptor to all interested users.
The proposed solution is composed of three major parts: the high-level,
shared GPIO proxy driver that arbitrates access to the shared pin and
exposes a regular GPIO chip interface to consumers, a low-level shared
GPIOLIB module that scans firmware nodes and creates auxiliary devices
that attach to the proxy driver and finally a set of core GPIOLIB
changes that plug the former into the GPIO lookup path.
The changes are implemented in a way that allows to seamlessly compile
out any code related to sharing GPIOs for systems that don't need it.
The practical use-case for this are the powerdown GPIOs shared by
speakers on Qualcomm db845c platform, however I have also extensively
tested it using gpio-virtuser on arm64 qemu with various DT
configurations.
For 'always-on' and 'boot-on' regulators, the set_machine_constraints()
may enable supply before enabling the main regulator, however if the
latter fails, the function returns with an error but the supply remains
enabled.
When this happens, the regulator_register() function continues on the
error path where it puts the supply regulator. Since enabling the supply
is not balanced with a disable call, a warning similar to the following
gets issued from _regulator_put():
[ 1.603889] WARNING: CPU: 2 PID: 44 at _regulator_put+0x8c/0xa0
[ 1.603908] Modules linked in:
[ 1.603926] CPU: 2 UID: 0 PID: 44 Comm: kworker/u16:3 Not tainted 6.18.0-rc4 #0 NONE
[ 1.603938] Hardware name: Qualcomm Technologies, Inc. IPQ9574/AP-AL02-C7 (DT)
[ 1.603945] Workqueue: async async_run_entry_fn
[ 1.603958] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 1.603967] pc : _regulator_put+0x8c/0xa0
[ 1.603976] lr : _regulator_put+0x7c/0xa0
...
[ 1.604140] Call trace:
[ 1.604145] _regulator_put+0x8c/0xa0 (P)
[ 1.604156] regulator_register+0x2ec/0xbf0
[ 1.604166] devm_regulator_register+0x60/0xb0
[ 1.604178] rpm_reg_probe+0x120/0x208
[ 1.604187] platform_probe+0x64/0xa8
...
In order to avoid this, change the set_machine_constraints() function to
disable the supply if enabling the main regulator fails.
Fixes: 05f224ca66 ("regulator: core: Clean enabling always-on regulators + their supplies")
Signed-off-by: Gabor Juhos <j4g8y7@gmail.com>
Link: https://patch.msgid.link/20251107-regulator-disable-supply-v1-1-c95f0536f1b5@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Forward critical supply events downstream so consumers can react in
time. An under-voltage event on an upstream rail may otherwise never
reach end devices (e.g. eMMC).
Register a notifier on a regulator's supply when the supply is resolved,
and forward only REGULATOR_EVENT_UNDER_VOLTAGE to the consumer's notifier
chain. Event handling is deferred to process context via a workqueue; the
consumer rdev is lifetime-pinned and the rdev lock is held while calling
the notifier chain. The notifier is unregistered on regulator teardown.
No DT/UAPI changes. Behavior applies to all regulators with a supply.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20251001105650.2391477-1-o.rempel@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
For ternary operators in the form of "a ? true : false", if 'a' itself
returns a boolean result, the ternary operator can be omitted. Remove
redundant ternary operators to clean up the code.
Signed-off-by: Liao Yuanhong <liaoyuanhong@vivo.com>
Message-ID: <20250828122737.43488-1-liaoyuanhong@vivo.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The logic in regulator_set_voltage() which checks for a non-convergence
condition on a stepped regulator is flawed.
regulator_set_voltage() checks if the error in target voltage has increased
or decreased, and returns -EWOULDBLOCK if the error has not decreased
enough. The correct non-convergence condition is:
new_delta - delta > -rdev->constraints->max_uV_step
or equivalently:
delta - new_delta < rdev->constraints->max_uV_step
But the currently used condition is:
new_delta - delta > rdev->constraints->max_uV_step
Which may cause an infinite loop if the voltage error doesn't converge.
Fix this by correcting the convergence condition.
Suggested-by: Jon Hunter <jonathanh@nvidia.com>
Fixes: d511206dc7 ("regulator: core: repeat voltage setting request for stepped regulators")
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Link: https://patch.msgid.link/20250729-b4-regulator-stepping-fix-v1-1-3f7b8c55d7d7@bootlin.com
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The regulator_set_voltage() function may exhibit unexpected behavior if the
target regulator has a maximum voltage step constraint. With such a
constraint, the regulator core may clamp the requested voltage to a lesser
value, to ensure that the voltage delta stays under the specified limit.
This means that the resulting regulator voltage depends on the current
voltage, as well as the requested range, which invalidates the assumption
that a repeated request for a specific voltage range will amount to a noop.
Considering the case of a regulator with a maximum voltage step constraint
of 1V:
initial voltage: 2.5V
consumer requests 4V
expected result: 3.5V
resulting voltage: 3.5V
consumer requests 4V again
expected result: 4V
actual result: 3.5V
Correct this by repeating attempts to balance the regulator voltage until
the result converges.
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Link: https://patch.msgid.link/20250718-regulator-stepping-v2-1-e28c9ac5d54a@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Failing to reset coupling_desc.n_coupled after freeing coupled_rdevs can
lead to NULL pointer dereference when regulators are accessed post-unbind.
This can happen during runtime PM or other regulator operations that rely
on coupling metadata.
For example, on ridesx4, unbinding the 'reg-dummy' platform device triggers
a panic in regulator_lock_recursive() due to stale coupling state.
Ensure n_coupled is set to 0 to prevent access to invalid pointers.
Signed-off-by: Alessandro Carminati <acarmina@redhat.com>
Link: https://patch.msgid.link/20250626083809.314842-1-acarmina@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull non-MM updates from Andrew Morton:
- The series "powerpc/crash: use generic crashkernel reservation" from
Sourabh Jain changes powerpc's kexec code to use more of the generic
layers.
- The series "get_maintainer: report subsystem status separately" from
Vlastimil Babka makes some long-requested improvements to the
get_maintainer output.
- The series "ucount: Simplify refcounting with rcuref_t" from
Sebastian Siewior cleans up and optimizing the refcounting in the
ucount code.
- The series "reboot: support runtime configuration of emergency
hw_protection action" from Ahmad Fatoum improves the ability for a
driver to perform an emergency system shutdown or reboot.
- The series "Converge on using secs_to_jiffies() part two" from Easwar
Hariharan performs further migrations from msecs_to_jiffies() to
secs_to_jiffies().
- The series "lib/interval_tree: add some test cases and cleanup" from
Wei Yang permits more userspace testing of kernel library code, adds
some more tests and performs some cleanups.
- The series "hung_task: Dump the blocking task stacktrace" from Masami
Hiramatsu arranges for the hung_task detector to dump the stack of
the blocking task and not just that of the blocked task.
- The series "resource: Split and use DEFINE_RES*() macros" from Andy
Shevchenko provides some cleanups to the resource definition macros.
- Plus the usual shower of singleton patches - please see the
individual changelogs for details.
* tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
mailmap: consolidate email addresses of Alexander Sverdlin
fs/procfs: fix the comment above proc_pid_wchan()
relay: use kasprintf() instead of fixed buffer formatting
resource: replace open coded variant of DEFINE_RES()
resource: replace open coded variants of DEFINE_RES_*_NAMED()
resource: replace open coded variant of DEFINE_RES_NAMED_DESC()
resource: split DEFINE_RES_NAMED_DESC() out of DEFINE_RES_NAMED()
samples: add hung_task detector mutex blocking sample
hung_task: show the blocker task if the task is hung on mutex
kexec_core: accept unaccepted kexec segments' destination addresses
watchdog/perf: optimize bytes copied and remove manual NUL-termination
lib/interval_tree: fix the comment of interval_tree_span_iter_next_gap()
lib/interval_tree: skip the check before go to the right subtree
lib/interval_tree: add test case for span iteration
lib/interval_tree: add test case for interval_tree_iter_xxx() helpers
lib/rbtree: add random seed
lib/rbtree: split tests
lib/rbtree: enable userland test suite for rbtree related data structure
checkpatch: describe --min-conf-desc-length
scripts/gdb/symbols: determine KASLR offset on s390
...
When the core detects permanent regulator hardware failure or imminent
power failure of a critical supply, it will call hw_protection_shutdown in
an attempt to do a limited orderly shutdown followed by powering off the
system.
This doesn't work out well for many unattended embedded systems that don't
have support for shutdown and that power on automatically when power is
supplied:
- A brief power cycle gets detected by the driver
- The kernel powers down the system and SoC goes into shutdown mode
- Power is restored
- The system remains oblivious to the restored power
- System needs to be manually power cycled for a duration long enough
to drain the capacitors
Allow users to fix this by calling the newly introduced
hw_protection_trigger() instead: This way the hw_protection commandline or
sysfs parameter is used to dictate the policy of dealing with the
regulator fault.
Link: https://lkml.kernel.org/r/20250217-hw_protection-reboot-v3-8-e1c09b090c0c@pengutronix.de
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Cc: Benson Leung <bleung@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Lukasz Luba <lukasz.luba@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Matteo Croce <teknoraver@meta.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Rob Herring (Arm) <robh@kernel.org>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently, we are unnecessarily holding a regulator_ww_class_mutex lock
when creating debugfs entries for a newly created regulator. This was
brought up as a concern in the discussion in commit cba6cfdc7c
("regulator: core: Avoid lockdep reports when resolving supplies").
This causes the following lockdep splat after executing
`ls /sys/kernel/debug` on my platform:
======================================================
WARNING: possible circular locking dependency detected
5.15.167-axis9-devel #1 Tainted: G O
------------------------------------------------------
ls/2146 is trying to acquire lock:
ffffff803a562918 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x40/0x88
but task is already holding lock:
ffffff80014497f8 (&sb->s_type->i_mutex_key#3){++++}-{3:3}, at: iterate_dir+0x50/0x1f4
which lock already depends on the new lock.
[...]
Chain exists of:
&mm->mmap_lock --> regulator_ww_class_mutex --> &sb->s_type->i_mutex_key#3
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#3);
lock(regulator_ww_class_mutex);
lock(&sb->s_type->i_mutex_key#3);
lock(&mm->mmap_lock);
*** DEADLOCK ***
This lock dependency still exists on the latest kernel and using a newer
non-tainted kernel would still cause this problem.
Fix by moving sysfs symlinking and creation of debugfs entries to after
the release of the regulator lock.
Fixes: cba6cfdc7c ("regulator: core: Avoid lockdep reports when resolving supplies")
Fixes: eaa7995c52 ("regulator: core: avoid regulator_resolve_supply() race condition")
Signed-off-by: Ludvig Pärsson <ludvig.parsson@axis.com>
Link: https://patch.msgid.link/20250305-regulator_lockdep_fix-v1-1-ab938b12e790@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This reverts commit cd7a38c40b.
When submitting the change above, it was thought that the origin of the
init_data should be a clear choice, from the driver or from DT but not
both.
It turns out some devices, such as qcom-msm8974-lge-nexus5-hammerhead,
relied on the old behaviour to override the init_data provided by the
driver, making it some kind of default if none is provided by the platform.
Using the init_data provided by the driver when it is present broke these
devices so revert the change to fixup the situation and add a comment
to make things a bit more clear
Reported-by: Luca Weiss <luca@lucaweiss.eu>
Closes: https://lore.kernel.org/lkml/5857103.DvuYhMxLoT@lucaweiss.eu
Fixes: cd7a38c40b ("regulator: core: do not silently ignore provided init_data")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20250211-regulator-init-data-fixup-v1-1-5ce1c6cff990@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Previously, the regulator core resolved its supply only from the parent
device or its children, ignoring the of_node specified in the
regulator_config structure.
This behavior causes issues in scenarios where multiple regulator devices
are registered for components described as children of a controller, each
with their own specific regulator supply.
For instance, in a PSE controller with multiple PIs (Power Interfaces),
each PI may have a distinct regulator supply. However, the regulator core
would incorrectly use the PSE controller node or its first child to look up
the regulator supply, rather than the node specified by the
regulator_config->of_node for the PI.
This update modifies the behavior to prioritize the of_node in
regulator_config for resolving the supply. This ensures correct resolution
of the power supply for each device. If no supply is found in the provided
of_node, the core falls back to searching within the parent device as
before.
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20250109-b4-feature_poe_arrange-v2-13-55ded947b510@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The machine specific regulator_init() appears to be unused.
It does not allow a lot of interaction with the regulator framework,
since nothing from the framework is passed along (desc, config,
etc ...)
Machine specific init may also be done with the added init_cb() in
the regulator description, so remove regulator_init().
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20241008-regulator-ignored-data-v2-3-d1251e0ee507@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Provide an initialisation callback to handle runtime parameters.
The idea is similar to the regulator_init() callback, but it provides
regulator specific structures, instead of just the driver specific data.
As an example, this allows the driver to amend the regulator constraints
based on runtime parameters if necessary.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20241008-regulator-ignored-data-v2-2-d1251e0ee507@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
On DT platforms, if a regulator init_data is provided in config, it is
silently ignored in favor of the DT parsing done by the framework, if
of_match is set.
of_match is an indication that init_data is expected to be set based on DT
and the parsing should be done by the regulator framework.
If the regulator provider passed init_data it must be because it is useful
somehow, in such case of_match should be clear.
If the driver expects the framework to initialize this data on its
own, it should leave init_data clear.
Warn if both init_data and of_match are set, then default to the provided
init_data.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20241008-regulator-ignored-data-v2-1-d1251e0ee507@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The to-be-introduced I2C component prober needs to enable regulator
supplies (and toggle GPIO pins) for the various components it intends
to probe. To support this, a new "pure DT lookup" method for getting
regulator supplies is needed, since the device normally requesting
the supply won't get created until after the component is probed to
be available.
Add a new of_regulator_get_optional() function for this. This mirrors
the existing regulator_get_optional() function, but is OF-specific.
The underlying code that supports the existing regulator_get*()
functions has been reworked in previous patches to support this
specific case.
Also convert an existing usage of "dev && dev->of_node" to
"dev_of_node(dev)".
Link: https://lore.kernel.org/all/20231220203537.83479-2-jernej.skrabec@gmail.com/ [1]
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://patch.msgid.link/20240925093807.1026949-2-wenst@chromium.org
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
_regulator_get() contains a lot of common code doing checks prior to the
regulator lookup and housekeeping work after the lookup. Almost all the
code could be shared with a OF-specific variant of _regulator_get().
Split out the common parts so that they can be reused. The OF-specific
version of _regulator_get() will be added in a subsequent patch.
No functional changes were made.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240911072751.365361-4-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The behavior of regulator_dev_lookup() for non-DT way has been broken
since the commit b8c3255457 ("regulator: Move OF-specific regulator
lookup code to of_regulator.c").
Before the commit, of_get_regulator() was used to get the regulator,
which returns NULL if the regulator is not found. So the regulator
will be looked up through regulator_lookup_by_name() if no matching
regulator is found in regulator_map_list.
However, currently, of_regulator_dev_lookup() is used to instead of
of_get_regulator(), but the variable 'r' is set to ERR_PTR(-ENODEV)
instead of NULL if the regulator is not found. In this case, if no
regulator is found in regulator_map_list, the variable 'r' is still
ERR_PTR(-ENODEV), So regulator_dev_lookup() returns the value of 'r'
directly instead of continuing to look up the regulator through
regulator_lookup_by_name().
Fixes: b8c3255457 ("regulator: Move OF-specific regulator lookup code to of_regulator.c")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20240911120338.526384-1-wei.fang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
There's still a bit of OF-specific code in the regulator device lookup
function.
Move those bits of code over to of_regulator.c, and create a new
function of_regulator_dev_lookup() to encapsulate the code moved out of
regulator_dev_lookup().
Also mark of_find_regulator_by_node() as static, since there are no
other users in other compile units.
There are no functional changes. A line alignment was also fixed.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://patch.msgid.link/20240904090016.2841572-4-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
kernel-doc complains about missing "Return" section for many documented
functions in the regulator core. Some with free-form return value
descriptions have been fixed in the previous patch. The remaining are
completely missing any mention of return values.
Add "Return" sections to these kerneldoc blocks with basic descriptions.
In a few cases where the functions don't call even more functions and
the error numbers are known, those are documented in detail.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240829085131.1361701-5-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
kernel-doc complains about missing "Return" section for many documented
functions in the regulator core. Many of them actually have descriptions
about the return values, just not in the format kernel-doc wants.
Convert these to use the proper "Return:" section header. The existing
descriptions have been reworded and moved around to fit the grammar and
formatting.
In a few cases where the functions don't call even more functions
and the error numbers are known, those are documented in detail.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240829085131.1361701-4-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The kerneldoc for regulator_is_supported_voltage() states that the
return value is a boolean. That is not correct, as it could return an
error number if the check failed.
Fix the description by expanding it to cover the valid return values and
error conditions. The description is also converted to a proper "Return"
section.
Fixes: c5f3939b8f ("regulator: core: Support fixed voltages in regulator_is_supported_voltage()")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240829085131.1361701-3-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The original error message simply said "get() with no identifier"
without any context as to what was requested or what device the
request was related to. The only thing the user or developer could
do was grep for the message in the full source tree.
Amend the error message to be more specific, and also use dev_*
to associate the error message with a device.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://patch.msgid.link/20240822072047.3097740-2-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull regulator updates from Mark Brown:
"There's one API update here, a new API factoring out a common pattern
for reference voltage supplies. These are supplies used as a reference
by analogue circuits where the consumer requests and enables the
supply, reads the voltage to calibrate the user and then never touches
it again. This is factored out into a single operation which just
returns the voltage and uses devm_ to manage the request and enable
portion.
Otherwise this has been a very quiet release, we've got some new
device support, some small fixes, housekeeping and cleanup work but
nothing substantial.
There's also some non-regulator changes in here, a number of users for
the new reference voltage API were merged along with it and some MFD
changes were pulled in as dependencies for new driver work.
Highlights:
- Add a new API for single operation handling of reference voltages
- Support for Allwinner AXP717 and D1, and NXP PCA9561A"
* tag 'regulator-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (33 commits)
regulator: sun20i: Add Allwinner D1 LDOs driver
regulator: dt-bindings: Add Allwinner D1 system LDOs
regulator: Mention regulator id in error message about dummy supplies
staging: iio: impedance-analyzer: ad5933: Use devm_regulator_get_enable_read_voltage()
iio: frequency: admv1013: Use devm_regulator_get_enable_read_voltage()
iio: addac: ad74115: Use devm_regulator_get_enable_read_voltage()
hwmon: (adc128d818) simplify final return in probe
regulator: devres: fix devm_regulator_get_enable_read_voltage() return
hwmon: (da9052) Use devm_regulator_get_enable_read_voltage()
hwmon: (adc128d818) Use devm_regulator_get_enable_read_voltage()
regulator: devres: add API for reference voltage supplies
regulator: rtq2208: Fix LDO discharge register and add vsel setting
regulator: dt-bindings: fixed-regulator: Add a preferred node name
regulator: axp20x: add support for the AXP717
mfd: axp20x: Add support for AXP717 PMIC
dt-bindings: mfd: x-powers,axp152: Document AXP717
regulator: axp20x: fix typo-ed identifier
dt-bindings: regulator: qcom,usb-vbus-regulator: Add PM7250B compatible
regulator: pca9450: add pca9451a support
regulator: dt-bindings: pca9450: add pca9451a support
...
regulator_get() may sometimes be called more than once for the same
consumer device, something which before commit dbe954d8f1 ("regulator:
core: Avoid debugfs: Directory ... already present! error") resulted in
errors being logged.
A couple of recent commits broke the handling of such cases so that
attributes are now erroneously created in the debugfs root directory the
second time a regulator is requested and the log is filled with errors
like:
debugfs: File 'uA_load' in directory '/' already present!
debugfs: File 'min_uV' in directory '/' already present!
debugfs: File 'max_uV' in directory '/' already present!
debugfs: File 'constraint_flags' in directory '/' already present!
on any further calls.
Fixes: 2715bb11cf ("regulator: core: Fix more error checking for debugfs_create_dir()")
Fixes: 08880713ce ("regulator: core: Streamline debugfs operations")
Cc: stable@vger.kernel.org
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20240509133304.8883-1-johan+linaro@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Linus Torvalds
Kees Cook
Bjorn Andersson
André Draszik
Bartosz Golaszewski
sparkhuang
Mark Brown
Bartosz Golaszewski
Gabor Juhos
Oleksij Rempel
Liao Yuanhong
Romain Gantois
Alessandro Carminati
Ahmad Fatoum
Christian Eggers
Ludvig Pärsson
Jerome Brunet
Alexander Stein
Kory Maincent
Anna-Maria Behnsen
Chen-Yu Tsai
Wei Fang
Biju Das
Johan Hovold