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path: root/drivers/regulator/core.c
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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>
2024-05-07regulator: Mention regulator id in error message about dummy suppliesUwe Kleine-König
With the name that is currently looked up it is considerably easier to understand the issue and fix the warning. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20240507104703.2070117-2-u.kleine-koenig@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2024-03-12regulator: core: Propagate the regulator state in case of exclusive getKory Maincent
Previously, performing an exclusive get on an already-enabled regulator resulted in inconsistent state initialization between child and parent regulators. While the child's counts were updated, its parent's counters remained unaffected. Consequently, attempting to disable an already-enabled exclusive regulator triggered unbalanced disables warnings from its parent regulator. This commit addresses the issue by propagating the enable state to the parent regulator using a regulator_enable call. This ensures consistent state management across the regulator hierarchy, preventing warnings! Signed-off-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://msgid.link/r/20240312091638.1266167-1-kory.maincent@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-03-05regulator: core: make regulator_class constantRicardo B. Marliere
Since commit 43a7206b0963 ("driver core: class: make class_register() take a const *"), the driver core allows for struct class to be in read-only memory, so move the regulator_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Link: https://msgid.link/r/20240305-class_cleanup-regulator-v1-1-4950345d6d8f@marliere.net Signed-off-by: Mark Brown <broonie@kernel.org>
2024-02-19regulator: core: Remove redundant assignment to variable possible_uVColin Ian King
The variable possible_uV being assigned a value that is never read, the control flow via the following goto statement takes a path where the variable is not accessed. The assignment is redundant and can be removed. Cleans up clang scan build warning: drivers/regulator/core.c:3935:3: warning: Value stored to 'possible_uV' is never read [deadcode.DeadStores] Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://msgid.link/r/20240216134918.2108262-1-colin.i.king@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-12-06regulator: event: Add regulator netlink event supportNaresh Solanki
This commit introduces netlink event support to the regulator subsystem. Changes: - Introduce event.c and regnl.h for netlink event handling. - Implement reg_generate_netlink_event to broadcast regulator events. - Update Makefile to include the new event.c file. Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com> Link: https://lore.kernel.org/r/20231205105207.1262928-1-naresh.solanki@9elements.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-13regulator: add under-voltage support (part 2)Mark Brown
Merge series from Oleksij Rempel <o.rempel@pengutronix.de>: This series add under-voltage and emergency shutdown for system critical regulators
2023-11-13regulator: core: Only increment use_count when enable_count changesRui Zhang
The use_count of a regulator should only be incremented when the enable_count changes from 0 to 1. Similarly, the use_count should only be decremented when the enable_count changes from 1 to 0. In the previous implementation, use_count was sometimes decremented to 0 when some consumer called unbalanced disable, leading to unexpected disable even the regulator is enabled by other consumers. With this change, the use_count accurately reflects the number of users which the regulator is enabled. This should make things more robust in the case where a consumer does leak references. Signed-off-by: Rui Zhang <zr.zhang@vivo.com> Link: https://lore.kernel.org/r/20231103074231.8031-1-zr.zhang@vivo.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-13regulator: core: Add option to prevent disabling unused regulatorsJavier Martinez Canillas
This may be useful for debugging and develompent purposes, when there are drivers that depend on regulators to be enabled but do not request them. It is inspired from the clk_ignore_unused and pd_ignore_unused parameters, that are used to keep firmware-enabled clocks and power domains on even if these are not used by drivers. The parameter is not expected to be used in normal cases and should not be needed on a platform with proper driver support. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Brian Masney <bmasney@redhat.com> Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/20231107190926.1185326-1-javierm@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-13regulator: Implement uv_survival_time for handling under-voltage eventsOleksij Rempel
Add 'uv_survival_time' field to regulation_constraints for specifying survival time post critical under-voltage event. Update the regulator notifier call chain and Device Tree property parsing to use this new field, allowing a configurable timeout before emergency shutdown. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/20231026144824.4065145-6-o.rempel@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-13regulator: Introduce handling for system-critical under-voltage eventsOleksij Rempel
Handle under-voltage events for crucial regulators to maintain system stability and avoid issues during power drops. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/20231026144824.4065145-3-o.rempel@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2023-09-26regulator/core: Revert "fix kobject release warning and memory leak in ↵Michał Mirosław
regulator_register()" This reverts commit 5f4b204b6b8153923d5be8002c5f7082985d153f. Since rdev->dev now has a release() callback, the proper way of freeing the initialized device can be restored. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/d7f469f3f7b1f0e1d52f9a7ede3f3c5703382090.1695077303.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>