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path: root/drivers/regulator/core.c
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2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
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>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
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>
2026-02-12regulator: core: Remove regulator supply_name length limitBjorn Andersson
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>
2026-01-09regulator: core: don't fail regulator_register() with missing required supplyAndré Draszik
Since commit 98e48cd9283d ("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>
2026-01-09regulator: core: reresolve unresolved supplies when availableAndré Draszik
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 3827b64dba27 ("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>
2026-01-09regulator: core: don't ignore errors from event forwarding setupAndré Draszik
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: 433e294c3c5b ("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>
2026-01-09regulator: core: remove dead code in regulator_resolve_supply()André Draszik
Since commit 98e48cd9283d ("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>
2026-01-09regulator: core: streamline supply resolution for always-on/boot-on regulatorsAndré Draszik
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 8a866d527ac0 ("regulator: core: Resolve supply name earlier to prevent double-init") (later updated by commit 520fb178212d ("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>
2026-01-09regulator: core: move supply check earlier in set_machine_constraints()André Draszik
Since commit 98e48cd9283d ("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 8a866d527ac0 ("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: 98e48cd9283d ("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>
2026-01-09regulator: core: fix locking in regulator_resolve_supply() error pathAndré Draszik
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: 36a1f1b6ddc6 ("regulator: core: Fix memory leak in regulator_resolve_supply()") Fixes: 8e5356a73604 ("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>
2026-01-09regulator: core: update two debug messagesAndré Draszik
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>
2025-12-03regulator: check the return value of gpiod_set_value_cansleep()Bartosz Golaszewski
gpiod_set_value_cansleep() now returns an integer and can indicate failures in the GPIO layer. Propagate any potential errors to regulator core. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com> Link: https://patch.msgid.link/20251203084737.15891-1-bartosz.golaszewski@oss.qualcomm.com Signed-off-by: Mark Brown <broonie@kernel.org>
2025-11-27regulator: core: Protect regulator_supply_alias_list with regulator_list_mutexsparkhuang
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: a06ccd9c3785f ("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>
2025-11-20gpio: improve support for shared GPIOsMark Brown
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.
2025-11-19regulator: make the subsystem aware of shared GPIOsBartosz Golaszewski
GPIOLIB is now aware of shared GPIOs and - for platforms where access to such pins is managed internally - we don't need to keep track of the enable count. Once all users in the kernel switch to using the new mechanism, we'll be able to drop the internal counting of users from the regulator code. Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Link: https://patch.msgid.link/20251112-gpio-shared-v4-10-b51f97b1abd8@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
2025-11-07regulator: core: disable supply if enabling main regulator failsGabor Juhos
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: 05f224ca6693 ("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>
2025-10-15regulator: core: forward undervoltage events downstream by defaultOleksij Rempel
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>
2025-08-28regulator: core: Remove redundant ternary operatorsLiao Yuanhong
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>
2025-07-29regulator: core: correct convergence check in regulator_set_voltage()Romain Gantois
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: d511206dc7443 ("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>
2025-07-18regulator: core: repeat voltage setting request for stepped regulatorsRomain Gantois
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>
2025-06-29regulator: core: fix NULL dereference on unbind due to stale coupling dataAlessandro Carminati
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>
2025-04-09regulator: don't compare raw GPIO descriptor pointersBartosz Golaszewski
There's no API contract saying that two GPIO descriptor pointers obtained with a call to gpiod_get() (or one of the variants), that refer to the same physical GPIO pin, always point to the same structure. Use the dedicated comparator function. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Link: https://patch.msgid.link/20250407-gpiod-is-equal-v1-2-7d85f568ae6e@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
2025-04-01Merge tag 'mm-nonmm-stable-2025-03-30-18-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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 ...
2025-03-16regulator: allow user configuration of hardware protection actionAhmad Fatoum
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>
2025-03-13regulator: check that dummy regulator has been probed before using itChristian Eggers
Due to asynchronous driver probing there is a chance that the dummy regulator hasn't already been probed when first accessing it. Cc: stable@vger.kernel.org Signed-off-by: Christian Eggers <ceggers@arri.de> Link: https://patch.msgid.link/20250313103051.32430-3-ceggers@arri.de Signed-off-by: Mark Brown <broonie@kernel.org>
2025-03-05regulator: core: Fix deadlock in create_regulator()Ludvig Pärsson
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 cba6cfdc7c3f ("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: cba6cfdc7c3f ("regulator: core: Avoid lockdep reports when resolving supplies") Fixes: eaa7995c529b ("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>
2025-02-11regulator: core: let dt properties override driver init_dataJerome Brunet
This reverts commit cd7a38c40b231350a3cd0fd774f4e6bb68c4b411. 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: cd7a38c40b23 ("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>
2025-01-22regulator: core: Add missing newline characterAlexander Stein
dev_err_probe() error messages need newline character. Fixes: 6eabfc018e8d ("regulator: core: Allow specifying an initial load w/ the bulk API") Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Link: https://patch.msgid.link/20250122072019.1926093-1-alexander.stein@ew.tq-group.com Signed-off-by: Mark Brown <broonie@kernel.org>
2025-01-17regulator: Add support for power budgetKory Maincent
Introduce power budget management for the regulator device. Enable tracking of available power capacity by providing helpers to request and release power budget allocations. Signed-off-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://patch.msgid.link/20250115-feature_regulator_pw_budget-v2-1-0a44b949e6bc@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2025-01-09regulator: core: Resolve supply using of_node from regulator_configKory Maincent (Dent Project)
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>
2024-11-21regulator: core: Ignore unset max_uA constraints in current limit checkKory Maincent (Dent Project)
We should only consider max_uA constraints if they are explicitly defined. In cases where it is not set, we should assume the regulator has no current limit. Signed-off-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://patch.msgid.link/20241121-feature_poe_port_prio-v3-2-83299fa6967c@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-10-22regulator: init_data handling updateMark Brown
Merge series from Jerome Brunet <jbrunet@baylibre.com>: This patchset groups the regulator patches around the init_data topic discussed on pmbus write protect patchset [1] [1]: https://lore.kernel.org/r/20240920-pmbus-wp-v1-0-d679ef31c483@baylibre.com
2024-10-22regulator: core: Use fsleep() to get best sleep mechanismAnna-Maria Behnsen
_regulator_delay_helper() implements the recommondation of the outdated documentation which sleep mechanism should be used. There is already a function in place which does everything and also maps to reality called fsleep(). Use fsleep() directly. Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://patch.msgid.link/20241014-devel-anna-maria-b4-timers-flseep-v3-11-dc8b907cb62f@linutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2024-10-22regulator: core: remove machine init callback from configJerome Brunet
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>
2024-10-22regulator: core: add callback to perform runtime initJerome Brunet
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>
2024-10-22regulator: core: do not silently ignore provided init_dataJerome Brunet
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>
2024-09-30regulator: Add of_regulator_get_optional() for pure DT regulator lookupChen-Yu Tsai
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>
2024-09-13regulator: Split up _regulator_get()Chen-Yu Tsai
_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>
2024-09-11regulator: core: fix the broken behavior of regulator_dev_lookup()Wei Fang
The behavior of regulator_dev_lookup() for non-DT way has been broken since the commit b8c325545714 ("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: b8c325545714 ("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>
2024-09-04regulator: Move OF-specific regulator lookup code to of_regulator.cChen-Yu Tsai
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>
2024-08-29regulator: Unify "negative error number" terminology in commentsChen-Yu Tsai
Previous commits cleaning up kerneldoc used the term "negative error number" to refer to error condition return values. Update remaining instances of other terminology such as "error code" or "errno" as well so the whole regulator subsystem is unified. 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/20240829085131.1361701-11-wenst@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org>
2024-08-29regulator: core: Add missing kerneldoc "Return" sectionsChen-Yu Tsai
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>
2024-08-29regulator: core: Fix incorrectly formatted kerneldoc "Return" sectionsChen-Yu Tsai
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>
2024-08-29regulator: core: Fix regulator_is_supported_voltage() kerneldoc return valueChen-Yu Tsai
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: c5f3939b8fe0 ("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>
2024-08-29regulator: core: Fix short description for _regulator_check_status_enabled()Chen-Yu Tsai
kernel-doc complains that _regulator_check_status_enabled() is missing a short description. Since the current description is already quite short, just trim it a bit more and use it as the short description. Fixes: f7d7ad42a9dc ("regulator: Allow regulators to verify enabled during enable()") 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/20240829085131.1361701-2-wenst@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org>
2024-08-22regulator: Clarify error message for "id == NULL" in _regulator_get()Chen-Yu Tsai
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>
2024-06-26regulator: core: Add helper for allow HW access to enable/disable regulatorBiju Das
Add a helper function that allow regulator consumers to allow low-level HW access, in order to enable/disable regulator in atomic context. The use-case for RZ/G2L SoC is to enable VBUS selection register based on vbus detection that happens in interrupt context. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://patch.msgid.link/20240616105402.45211-4-biju.das.jz@bp.renesas.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-06-10regulator: core: Fix modpost error "regulator_get_regmap" undefinedBiju Das
Fix the modpost error "regulator_get_regmap" undefined by adding export symbol. Fixes: 04eca28cde52 ("regulator: Add helpers for low-level register access") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202406110117.mk5UR3VZ-lkp@intel.com Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20240610195532.175942-1-biju.das.jz@bp.renesas.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-05-14Merge tag 'regulator-v6.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator 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 ...
2024-05-09regulator: core: fix debugfs creation regressionJohan Hovold
regulator_get() may sometimes be called more than once for the same consumer device, something which before commit dbe954d8f163 ("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: 2715bb11cfff ("regulator: core: Fix more error checking for debugfs_create_dir()") Fixes: 08880713ceec ("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>