kernel/linux.git/drivers/regulator/core.c, branch v6.12.80

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

2026-03-04T12:19:54+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

2025-12-18T12:55:11+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

2025-12-18T12:54:55+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

2025-08-01T08:48:39+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

2025-03-28T21:03:29+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: Add missing newline character

2025-02-08T08:58:01+00:00

[ Upstream commit 155c569fa4c3b340fbf8571a0e42dd415c025377 ] 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 Link: https://patch.msgid.link/20250122072019.1926093-1-alexander.stein@ew.tq-group.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regulator: Split up _regulator_get()

2024-09-13T16:39:48+00:00

_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 Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20240911072751.365361-4-wenst@chromium.org Signed-off-by: Mark Brown

regulator: core: fix the broken behavior of regulator_dev_lookup()

2024-09-11T14:39:01+00:00

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 Link: https://patch.msgid.link/20240911120338.526384-1-wei.fang@nxp.com Signed-off-by: Mark Brown

regulator: Move OF-specific regulator lookup code to of_regulator.c

2024-09-04T12:15:21+00:00

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 Link: https://patch.msgid.link/20240904090016.2841572-4-wenst@chromium.org Signed-off-by: Mark Brown

regulator: Unify "negative error number" terminology in comments

2024-08-29T13:20:30+00:00

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 Reported-by: Andy Shevchenko Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20240829085131.1361701-11-wenst@chromium.org Signed-off-by: Mark Brown