kernel/linux.git/drivers/regulator/core.c, branch v5.15.209

regulator: core: move supply check earlier in set_machine_constraints()

2026-03-04T12:19:31+00:00

[ Upstream commit 86a8eeb0e913f4b6a55dabba5122098d4e805e55 ] 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 Link: https://patch.msgid.link/20260109-regulators-defer-v2-3-1a25dc968e60@linaro.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: core: Protect regulator_supply_alias_list with regulator_list_mutex

2026-01-19T12:09:35+00:00

[ Upstream commit 0cc15a10c3b4ab14cd71b779fd5c9ca0cb2bc30d ] 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 Reviewed-by: Charles Keepax Link: https://patch.msgid.link/20251127025716.5440-1-huangshaobo3@xiaomi.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: core: disable supply if enabling main regulator fails

2026-01-19T12:09:26+00:00

[ Upstream commit fb1ebb10468da414d57153ddebaab29c38ef1a78 ] 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 Link: https://patch.msgid.link/20251107-regulator-disable-supply-v1-1-c95f0536f1b5@gmail.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: core: fix NULL dereference on unbind due to stale coupling data

2025-08-28T14:24:03+00:00

[ Upstream commit ca46946a482238b0cdea459fb82fc837fb36260e ] 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 Link: https://patch.msgid.link/20250626083809.314842-1-acarmina@redhat.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: check that dummy regulator has been probed before using it

2025-04-10T12:31:54+00:00

commit 2c7a50bec4958f1d1c84d19cde518d0e96a676fd upstream. 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 Link: https://patch.msgid.link/20250313103051.32430-3-ceggers@arri.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman

regulator: core: Fix modpost error "regulator_get_regmap" undefined

2024-07-05T07:14:32+00:00

[ Upstream commit 3f60497c658d2072714d097a177612d34b34aa3d ] 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 Closes: https://lore.kernel.org/oe-kbuild-all/202406110117.mk5UR3VZ-lkp@intel.com Signed-off-by: Biju Das Link: https://lore.kernel.org/r/20240610195532.175942-1-biju.das.jz@bp.renesas.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: core: fix debugfs creation regression

2024-05-17T09:51:05+00:00

commit 2a4b49bb58123bad6ec0e07b02845f74c23d5e04 upstream. 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 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20240509133304.8883-1-johan+linaro@kernel.org Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman

regulator: core: Only increment use_count when enable_count changes

2024-02-23T07:54:37+00:00

[ Upstream commit 7993d3a9c34f609c02171e115fd12c10e2105ff4 ] 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 Link: https://lore.kernel.org/r/20231103074231.8031-1-zr.zhang@vivo.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator/core: Revert "fix kobject release warning and memory leak in regulator_register()"

2023-10-25T09:59:00+00:00

[ Upstream commit 6e800968f6a715c0661716d2ec5e1f56ed9f9c08 ] 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 Link: https://lore.kernel.org/r/d7f469f3f7b1f0e1d52f9a7ede3f3c5703382090.1695077303.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: core: Streamline debugfs operations

2023-07-23T11:46:50+00:00

[ Upstream commit 08880713ceec023dd94d634f1e8902728c385939 ] If CONFIG_DEBUG_FS is not set: regulator: Failed to create debugfs directory ... regulator-dummy: Failed to create debugfs directory As per the comments for debugfs_create_dir(), errors returned by this function should be expected, and ignored: * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. * * NOTE: it's expected that most callers should _ignore_ the errors returned * by this function. Other debugfs functions handle the fact that the "dentry" * passed to them could be an error and they don't crash in that case. * Drivers should generally work fine even if debugfs fails to init anyway. Adhere to the debugfs spirit, and streamline all operations by: 1. Demoting the importance of the printed error messages to debug level, like is already done in create_regulator(), 2. Further ignoring any returned errors, as by design, all debugfs functions are no-ops when passed an error pointer. Fixes: 2bf1c45be3b8f3a3 ("regulator: Fix error checking for debugfs_create_dir") Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/2f8bb6e113359ddfab7b59e4d4274bd4c06d6d0a.1685013051.git.geert+renesas@glider.be Signed-off-by: Mark Brown Signed-off-by: Sasha Levin