Sometimes regulator_get() gets called twice for the same supply on the
same device. This may happen e.g. when a framework / library is used
which uses the regulator; and the driver itself also needs to enable
the regulator in some cases where the framework will not enable it.
Commit ff268b56ce ("regulator: core: Don't spew backtraces on
duplicate sysfs") already takes care of the backtrace which would
trigger when creating a duplicate consumer symlink under
/sys/class/regulator/regulator.%d in this scenario.
Commit c33d442328 ("debugfs: make error message a bit more verbose")
causes a new error to get logged in this scenario:
[ 26.938425] debugfs: Directory 'wm5102-codec-MICVDD' with parent 'spi-WM510204:00-MICVDD' already present!
There is no _nowarn variant of debugfs_create_dir(), but we can detect
and avoid this problem by checking the return value of the earlier
sysfs_create_link_nowarn() call.
Add a check for the earlier sysfs_create_link_nowarn() failing with
-EEXIST and skip the debugfs_create_dir() call in that case, avoiding
this error getting logged.
Fixes: c33d442328 ("debugfs: make error message a bit more verbose")
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210122183250.370571-1-hdegoede@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Make regulator_sync_voltage() to re-balance voltage state of a coupled
regulators instead of changing the voltage directly.
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Tested-by: Dmitry Osipenko <digetx@gmail.com> # A500 T20 and Nexus7 T30
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210122174311.28230-1-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
With commit eaa7995c52 (regulator: core: avoid
regulator_resolve_supply() race condition) we started holding the rdev
lock while resolving supplies, an operation that requires holding the
regulator_list_mutex. This results in lockdep warnings since in other
places we take the list mutex then the mutex on an individual rdev.
Since the goal is to make sure that we don't call set_supply() twice
rather than a concern about the cost of resolution pull the rdev lock
and check for duplicate resolution down to immediately before we do the
set_supply() and drop it again once the allocation is done.
Fixes: eaa7995c52 (regulator: core: avoid regulator_resolve_supply() race condition)
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210122132042.10306-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The final step in regulator_register() is to call
regulator_resolve_supply() for each registered regulator
(including the one in the process of being registered). The
regulator_resolve_supply() function first checks if rdev->supply
is NULL, then it performs various steps to try to find the supply.
If successful, rdev->supply is set inside of set_supply().
This procedure can encounter a race condition if two concurrent
tasks call regulator_register() near to each other on separate CPUs
and one of the regulators has rdev->supply_name specified. There
is currently nothing guaranteeing atomicity between the rdev->supply
check and set steps. Thus, both tasks can observe rdev->supply==NULL
in their regulator_resolve_supply() calls. This then results in
both creating a struct regulator for the supply. One ends up
actually stored in rdev->supply and the other is lost (though still
present in the supply's consumer_list).
Here is a kernel log snippet showing the issue:
[ 12.421768] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[ 12.425854] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[ 12.429064] debugfs: Directory 'regulator.4-SUPPLY' with parent
'17a00000.rsc:rpmh-regulator-gfxlvl-pm8350_s5_level'
already present!
Avoid this race condition by holding the rdev->mutex lock inside
of regulator_resolve_supply() while checking and setting
rdev->supply.
Signed-off-by: David Collins <collinsd@codeaurora.org>
Link: https://lore.kernel.org/r/1610068562-4410-1-git-send-email-collinsd@codeaurora.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The function regulator_set_device_supply() is referenced a few times in
comments in regulator/core.c; however this function was removed a long
time ago by commit a5766f11cf ("regulator: core - Rework machine API to
remove string based functions."). Update those references to point to
set_consumer_device_supply(), which replaced the old function.
Signed-off-by: Daniel Scally <djrscally@gmail.com>
Link: https://lore.kernel.org/r/20210103165541.784360-1-djrscally@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Selectors lower than linear_min_sel should not be considered invalid.
Thus return zero in case _regulator_list_voltage(),
regulator_list_hardware_vsel() or regulator_list_voltage_table()
receives such selectors as argument.
Fixes: bdcd117757 ("regulator: core: validate selector against linear_min_sel")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/1606325147-606-1-git-send-email-claudiu.beznea@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Hi,
This series adds support for ramp delay on mcp16502. It also adds
some cleanup on mcp16502.
Apart from that patches 1/6 fixes the selector validation in case
the regulator::desc::linear_min_sel is not zero.
Thank you,
Claudiu Beznea
Changes in v3:
- fix compilation error in patch 5/6
Reported-by: kernel test robot <lkp@intel.com>
Changes in v2:
- rebase on top of regulator/for-next
- checked 1/6 and 3/6 applies on top of regulator/for-5.10
Claudiu Beznea (6):
regulator: core: validate selector against linear_min_sel
regulator: core: do not continue if selector match
regulator: mcp16502: add linear_min_sel
regulator: mcp16502: adapt for get/set on other registers
regulator: mcp16502: add support for ramp delay
regulator: mcp16502: remove void documentation of struct mcp16502
drivers/regulator/core.c | 12 +++-
drivers/regulator/helpers.c | 3 +-
drivers/regulator/mcp16502.c | 135 ++++++++++++++++++++++++++++++++++++-------
3 files changed, 127 insertions(+), 23 deletions(-)
--
2.7.4
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
There are regulators who's min selector is not zero. Selectors loops
(looping b/w zero and regulator::desc::n_voltages) might throw errors
because invalid selectors are used (lower than
regulator::desc::linear_min_sel). For this situations validate selectors
against regulator::desc::linear_min_sel.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/1605280870-32432-2-git-send-email-claudiu.beznea@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Workaround regulators whose supply name happens to be the same as its
own name. This fixes boards that used to work before the early supply
resolving was removed. The error message is left in place so that
offending drivers can be detected.
Fixes: aea6cb9970 ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1
Link: https://lore.kernel.org/r/d703acde2a93100c3c7a81059d716c50ad1b1f52.1605226675.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
When a regulator's name equals its supply's name the
regulator_resolve_supply() recurses indefinitely. Add a check
so that debugging the problem is easier. The "fixed" commit
just exposed the problem.
Fixes: aea6cb9970 ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1
Link: https://lore.kernel.org/r/c6171057cfc0896f950c4d8cb82df0f9f1b89ad9.1605226675.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixed commit introduced a possible second call to
set_machine_constraints() and that allocates memory for
rdev->constraints. Move the allocation to the caller so
it's easier to manage and done once.
Fixes: aea6cb9970 ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1
Link: https://lore.kernel.org/r/78c3d4016cebc08d441aad18cb924b4e4d9cf9df.1605226675.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
In regulator_late_cleanup when is_enabled failed, don't try to disable
the regulator since it would likely to fail too and causing confusing
error messages.
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Link: https://lore.kernel.org/r/20201106064817.3290927-1-pihsun@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
regulator_get_voltage_rdev() is called in regulator probe() when
applying machine constraints. The "fixed" commit exposed the problem
that non-bypassed regulators can forward the request to its parent
(like bypassed ones) supply. Return -EPROBE_DEFER when the supply
is expected but not resolved yet.
Fixes: aea6cb9970 ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reported-by: Ondřej Jirman <megous@megous.com>
Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-by: Ondřej Jirman <megous@megous.com>
Link: https://lore.kernel.org/r/a9041d68b4d35e4a2dd71629c8a6422662acb5ee.1604351936.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
If debugging is disabled, print_constraints() does not print the actual
constraints, but still performs some processing and string formatting,
only to throw away the result later.
Fix this by moving all constraint debug processing to a separate
function, and replacing it by a dummy when debugging is disabled.
This reduces kernel size by almost 800 bytes (on arm/arm64).
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20201005131546.22448-1-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulator drivers may be defining very long names: this is the
case with the qcom_smd and qcom_spmi regulators, where we need to
parse the regulator parents from DT.
For clarity, this is an example:
{ "l13a", QCOM_SMD_RPM_LDOA, 13, &pm660_ht_lvpldo,
"vdd_l8_l9_l10_l11_l12_l13_l14" },
pm660-regulators {
...
vdd_l8_l9_l10_l11_l12_l13_l14-supply = <&vreg_s4a_2p04>
...
};
Now, with a 32 characters limit, the function is trying to parse,
exactly, "vdd_l8_l9_l10_l11_l12_l13_l14-s" (32 chars) instead of
the right one, which is 37 chars long in this specific case.
... And this is not only the case with PM660/PM660L, but also with
PMA8084, PM8916, PM8950 and others that are not implemented yet.
The length of 64 chars was chosen based on the longest parsed property
name that I could find, which is in PM8916, and would be 53 characters
long.
At that point, rounding that to 64 looked like being the best idea.
Signed-off-by: AngeloGioacchino Del Regno <kholk11@gmail.com>
Link: https://lore.kernel.org/r/20200926125549.13191-2-kholk11@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When creating a new regulator its supply cannot create the sysfs link
because the device is not yet published. Remove early supply resolving
since it will be done later anyway. This makes the following error
disappear and the symlinks get created instead.
DCDC_REG1: supplied by VSYS
VSYS: could not add device link regulator.3 err -2
Note: It doesn't fix the problem for bypassed regulators, though.
Fixes: 45389c4752 ("regulator: core: Add early supply resolution for regulators")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/ba09e0a8617ffeeb25cb4affffe6f3149319cef8.1601155770.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Initial support for ROHM BD9576MUF and BD9573MUF PMICs.
These PMICs are primarily intended to be used to power the R-Car family
processors. BD9576MUF includes some additional safety features the
BD9573MUF does not have. This initial version of drivers does not
utilize these features and for now the SW behaviour is identical.
Please note that this version of drivers is only tested on BD9576MUF
but according to the data-sheets the relevant parts of registers should
be same so drivers should also work on BD9573MUF.
This patch series includes MFD, watchdog and regulator drivers with
basic functionality such as:
- Enabling and pinging the watchdog
- configuring watchog timeout / window from device-tree
- reading regulator states/voltages
- enabling/disabling VOUT1 (VD50) when control mode B is used.
This patch series does not bring interrupt support. BD9576MUF and BD9573MUF
are designed to keep the IRQ line low for whole duration of error
condition. IRQ can't be 'acked'. So proper IRQ support would require
some IRQ limiter implementation (delayed unmask?) in order to not hog
the CPU.
---
Matti Vaittinen (6):
dt_bindings: mfd: Add ROHM BD9576MUF and BD9573MUF PMICs
dt_bindings: regulator: Add ROHM BD9576MUF and BD9573MUF PMICs
mfd: Support ROHM BD9576MUF and BD9573MUF
wdt: Support wdt on ROHM BD9576MUF and BD9573MUF
regulator: Support ROHM BD9576MUF and BD9573MUF
MAINTAINERS: Add ROHM BD9576MUF and BD9573MUF drivers
.../bindings/mfd/rohm,bd9576-pmic.yaml | 129 +++++++
.../regulator/rohm,bd9576-regulator.yaml | 33 ++
MAINTAINERS | 4 +
drivers/mfd/Kconfig | 11 +
drivers/mfd/Makefile | 1 +
drivers/mfd/rohm-bd9576.c | 130 +++++++
drivers/regulator/Kconfig | 10 +
drivers/regulator/Makefile | 1 +
drivers/regulator/bd9576-regulator.c | 337 ++++++++++++++++++
drivers/watchdog/Kconfig | 13 +
drivers/watchdog/Makefile | 1 +
drivers/watchdog/bd9576_wdt.c | 295 +++++++++++++++
include/linux/mfd/rohm-bd957x.h | 61 ++++
include/linux/mfd/rohm-generic.h | 2 +
14 files changed, 1028 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml
create mode 100644 Documentation/devicetree/bindings/regulator/rohm,bd9576-regulator.yaml
create mode 100644 drivers/mfd/rohm-bd9576.c
create mode 100644 drivers/regulator/bd9576-regulator.c
create mode 100644 drivers/watchdog/bd9576_wdt.c
create mode 100644 include/linux/mfd/rohm-bd957x.h
base-commit: f4d51dffc6
--
2.21.0
--
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND
~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]
The biggest set of fixes here is those from Michał Mirosław fixing some
locking issues with coupled regulators that are triggered in cases where
a coupled regulator is used by a device involved in fs_reclaim like eMMC
storage. These are relatively serious for the affected systems, though
the circumstances where they trigger are very rare.
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Merge tag 'regulator-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"The biggest set of fixes here is those from Michał Mirosław fixing
some locking issues with coupled regulators that are triggered in
cases where a coupled regulator is used by a device involved in
fs_reclaim like eMMC storage.
These are relatively serious for the affected systems, though the
circumstances where they trigger are very rare"
* tag 'regulator-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: pwm: Fix machine constraints application
regulator: core: Fix slab-out-of-bounds in regulator_unlock_recursive()
regulator: remove superfluous lock in regulator_resolve_coupling()
regulator: cleanup regulator_ena_gpio_free()
regulator: plug of_node leak in regulator_register()'s error path
regulator: push allocation in set_consumer_device_supply() out of lock
regulator: push allocations in create_regulator() outside of lock
regulator: push allocation in regulator_ena_gpio_request() out of lock
regulator: push allocation in regulator_init_coupling() outside of lock
regulator: fix spelling mistake "Cant" -> "Can't"
regulator: cros-ec-regulator: Add NULL test for devm_kmemdup call
Since 3801b86aa4 ("regulator: Refactor supply implementation
to work as regular consumers") we no longer cascade notifications
and so notifier head's built-in rwsem is enough to protect the
notifier chain. Remove the requirement to fix one case where
rdev->mutex might be forced to be taken recursively.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/5a0da9017c69a4dbc3f9b50f44476fce80a73387.1597032945.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
The recent commit 7d8196641e ("regulator: Remove pointer table
overallocation") changed the size of coupled_rdevs and now KASAN is able
to detect slab-out-of-bounds problem in regulator_unlock_recursive(),
which is a legit problem caused by a typo in the code. The recursive
unlock function uses n_coupled value of a parent regulator for unlocking
supply regulator, while supply's n_coupled should be used. In practice
problem may only affect platforms that use coupled regulators.
Cc: stable@vger.kernel.org # 5.0+
Fixes: f8702f9e4a ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200831204335.19489-1-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
For systems that have eg. eMMC storage using voltage regulator, memory
reclaim path might call back into regulator subsystem. This means we
have to make sure no allocations happen with a regulator or regulator
list locked.
After this series I see no more lockdep complaints on my test system,
but please review and test further.
First four patches move allocations out of locked regions, next three
came as a drive-by cleanups.
---
v2: fix bug in patch #4 spotted by kernel test robot
reworded commit #7 description
Michał Mirosław (7):
regulator: push allocation in regulator_init_coupling() outside of
lock
regulator: push allocation in regulator_ena_gpio_request() out of lock
regulator: push allocations in create_regulator() outside of lock
regulator: push allocation in set_consumer_device_supply() out of lock
regulator: plug of_node leak in regulator_register()'s error path
regulator: cleanup regulator_ena_gpio_free()
regulator: remove superfluous lock in regulator_resolve_coupling()
drivers/regulator/core.c | 164 +++++++++++++++++++++------------------
1 file changed, 87 insertions(+), 77 deletions(-)
--
2.20.1
I see it takes about 5us per regulator to grab the lock, check that this
regulator isn't going to do anything for suspend, and then release the
lock. When that is combined with PMICs that have dozens of regulators we
get into a state where we spend a few miliseconds doing a bunch of
locking operations synchronously to figure out that there's nothing to
do. Let's reorganize the code here a bit so that we don't grab the lock
until we're actually going to do something so that suspend is a little
faster.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200804070837.1084024-1-swboyd@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The code modifies rdev, but locks c_rdev instead. Remove the lock
as this is held together by regulator_list_mutex taken in the caller.
Fixes: f9503385b1 ("regulator: core: Mutually resolve regulators coupling")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/25eb81cefb37a646f3e44eaaf1d8ae8881cfde52.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Since only regulator_ena_gpio_request() allocates rdev->ena_pin, and it
guarantees that same gpiod gets same pin structure, it is enough to
compare just the pointers. Also we know there can be only one matching
entry on the list. Rework the code take advantage of the facts.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/3ff002c7aa3bd774491af4291a9df23541fcf892.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
By calling device_initialize() earlier and noting that kfree(NULL) is
ok, we can save a bit of code in error handling and plug of_node leak.
Fixed commit already did part of the work.
Fixes: 9177514ce3 ("regulator: fix memory leak on error path of regulator_register()")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f5035b1b4d40745e66bacd571bbbb5e4644d21a1.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Move all allocations outside of the regulator_lock()ed section.
======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #535 Not tainted
------------------------------------------------------
f2fs_discard-179:7/702 is trying to acquire lock:
c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0
but task is already holding lock:
cb95b080 (&dcc->cmd_lock){+.+.}-{3:3}, at: __issue_discard_cmd+0xec/0x5f8
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
[...]
-> #3 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire.part.11+0x40/0x50
fs_reclaim_acquire+0x24/0x28
__kmalloc_track_caller+0x54/0x218
kstrdup+0x40/0x5c
create_regulator+0xf4/0x368
regulator_resolve_supply+0x1a0/0x200
regulator_register+0x9c8/0x163c
[...]
other info that might help us debug this:
Chain exists of:
regulator_list_mutex --> &sit_i->sentry_lock --> &dcc->cmd_lock
[...]
Fixes: f8702f9e4a ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/6eebc99b2474f4ffaa0405b15178ece0e7e4f608.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Move another allocation out of regulator_list_mutex-protected region, as
reclaim might want to take the same lock.
WARNING: possible circular locking dependency detected
5.7.13+ #534 Not tainted
------------------------------------------------------
kswapd0/383 is trying to acquire lock:
c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0
but task is already holding lock:
c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire.part.11+0x40/0x50
fs_reclaim_acquire+0x24/0x28
kmem_cache_alloc_trace+0x40/0x1e8
regulator_register+0x384/0x1630
devm_regulator_register+0x50/0x84
reg_fixed_voltage_probe+0x248/0x35c
[...]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(regulator_list_mutex);
lock(fs_reclaim);
lock(regulator_list_mutex);
*** DEADLOCK ***
[...]
2 locks held by kswapd0/383:
#0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
#1: cb70e5e0 (hctx->srcu){....}-{0:0}, at: hctx_lock+0x60/0xb8
[...]
Fixes: 541d052d72 ("regulator: core: Only support passing enable GPIO descriptors")
[this commit only changes context]
Fixes: f8702f9e4a ("regulator: core: Use ww_mutex for regulators locking")
[this is when the regulator_list_mutex was introduced in reclaim locking path]
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/41fe6a9670335721b48e8f5195038c3d67a3bf92.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Allocating memory with regulator_list_mutex held makes lockdep unhappy
when memory pressure makes the system do fs_reclaim on eg. eMMC using
a regulator. Push the lock inside regulator_init_coupling() after the
allocation.
======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #533 Not tainted
------------------------------------------------------
kswapd0/383 is trying to acquire lock:
cca78ca4 (&sbi->write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154
but task is already holding lock:
c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire.part.11+0x40/0x50
fs_reclaim_acquire+0x24/0x28
__kmalloc+0x54/0x218
regulator_register+0x860/0x1584
dummy_regulator_probe+0x60/0xa8
[...]
other info that might help us debug this:
Chain exists of:
&sbi->write_io[i][j].io_rwsem --> regulator_list_mutex --> fs_reclaim
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(regulator_list_mutex);
lock(fs_reclaim);
lock(&sbi->write_io[i][j].io_rwsem);
*** DEADLOCK ***
1 lock held by kswapd0/383:
#0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
[...]
Fixes: d8ca7d184b ("regulator: core: Introduce API for regulators coupling customization")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
The change corrects registration and deregistration on error path
of a regulator, the problem was manifested by a reported memory
leak on deferred probe:
as3722-regulator as3722-regulator: regulator 13 register failed -517
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xecc43740 (size 64):
comm "swapper/0", pid 1, jiffies 4294937640 (age 712.880s)
hex dump (first 32 bytes):
72 65 67 75 6c 61 74 6f 72 2e 32 34 00 5a 5a 5a regulator.24.ZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ
backtrace:
[<0c4c3d1c>] __kmalloc_track_caller+0x15c/0x2c0
[<40c0ad48>] kvasprintf+0x64/0xd4
[<109abd29>] kvasprintf_const+0x70/0x84
[<c4215946>] kobject_set_name_vargs+0x34/0xa8
[<62282ea2>] dev_set_name+0x40/0x64
[<a39b6757>] regulator_register+0x3a4/0x1344
[<16a9543f>] devm_regulator_register+0x4c/0x84
[<51a4c6a1>] as3722_regulator_probe+0x294/0x754
...
The memory leak problem was introduced as a side ef another fix in
regulator_register() error path, I believe that the proper fix is
to decouple device_register() function into its two compounds and
initialize a struct device before assigning any values to its fields
and then using it before actual registration of a device happens.
This lets to call put_device() safely after initialization, and, since
now a release callback is called, kfree(rdev->constraints) shall be
removed to exclude a double free condition.
Fixes: a3cde9534e ("regulator: core: fix regulator_register() error paths to properly release rdev")
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Cc: Wen Yang <wenyang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20200724005013.23278-1-vz@mleia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Part of the regulator_get() code is already factored out into
create_regulator(). This patch factors out some of the regulator_put()
code into destroy_regulator() so that create_regulator() has a
corresponding unwind function. Subsequent patches will use this
function.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200716042053.1927676-3-saravanak@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators might need to verify that they have indeed been enabled
after the enable() call is made and enable_time delay has passed.
This is implemented by repeatedly checking is_enabled() upto
poll_enabled_time, waiting for the already calculated enable delay in
each iteration.
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://lore.kernel.org/r/20200622124110.20971-2-sumit.semwal@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Add new trace points for the start and end of enabling bypass on a
regulator, to allow monitoring of when regulators are moved into bypass
and how long that takes.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20200529152216.9671-1-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Hi!
This patchset is another attempt to fix the regulator coupling on
Exynos5800/5422 SoCs. Here are links to the previous attempts:
https://lore.kernel.org/linux-samsung-soc/20191008101709.qVNy8eijBi0LynOteWFMnTg4GUwKG599n6OyYoX1Abs@z/https://lore.kernel.org/lkml/20191017102758.8104-1-m.szyprowski@samsung.com/https://lore.kernel.org/linux-pm/cover.1589528491.git.viresh.kumar@linaro.org/https://lore.kernel.org/linux-pm/20200528131130.17984-1-m.szyprowski@samsung.com/
The problem is with "vdd_int" regulator coupled with "vdd_arm" on Odroid
XU3/XU4 boards family. "vdd_arm" is handled by CPUfreq. "vdd_int" is
handled by devfreq. CPUfreq initialized quite early during boot and it
starts changing OPPs and "vdd_arm" value. Sometimes CPU activity during
boot goes down and some low-frequency OPPs are selected, what in turn
causes lowering "vdd_arm". This happens before devfreq applies its
requirements on "vdd_int". Regulator balancing code reduces "vdd_arm"
voltage value, what in turn causes lowering "vdd_int" value to the lowest
possible value. This is much below the operation point of the wcore bus,
which still runs at the highest frequency.
The issue was hard to notice because in the most cases the board managed
to boot properly, even when the regulator was set to lowest value allowed
by the regulator constraints. However, it caused some random issues,
which can be observed as "Unhandled prefetch abort" or low USB stability.
Adding more and more special cases to the generic code has been rejected,
so the only way to ensure the desired behavior on Exynos5800-based SoCs
is to make a custom regulator coupler driver.
Best regards,
Marek Szyprowski
Patch summary:
Marek Szyprowski (2):
regulator: extract voltage balancing code to separate function
soc: samsung: Add simple voltage coupler for Exynos5800
arch/arm/mach-exynos/Kconfig | 1 +
drivers/regulator/core.c | 49 ++++++++-------
drivers/soc/samsung/Kconfig | 3 +
drivers/soc/samsung/Makefile | 1 +
.../soc/samsung/exynos-regulator-coupler.c | 59 +++++++++++++++++++
include/linux/regulator/coupler.h | 8 +++
6 files changed, 101 insertions(+), 20 deletions(-)
create mode 100644 drivers/soc/samsung/exynos-regulator-coupler.c
--
2.17.1
base-commit: 8f3d9f3542
Move the coupled regulators voltage balancing code to the separate
function and allow to call it from the custom regulator couplers.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200529124940.10675-2-m.szyprowski@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add maintainer entries to a few ROHM devices and Linear Ranges
Linear Ranges helpers were refactored out of regulator core to lib so
that other drivers could utilize them too. (I guess power/supply drivers
and possibly clk drivers can benefit from them). As regulators is
currently the main user it makes sense the changes to linear_ranges go
through Mark's tree.
During past two years few ROHM PMIC drivers have been added to
mainstream. They deserve a supporter from ROHM side too :)
Patch 1:
Maintainer entries for few ROHM IC drivers
Patch 2:
Maintainer entry for linear ranges helpers
---
Matti Vaittinen (2):
MAINTAINERS: Add entry for ROHM power management ICs
MAINTAINERS: Add maintainer entry for linear ranges helper
MAINTAINERS | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
base-commit: b9bbe6ed63
--
2.21.0
--
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND
~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]
This reverts commit dca0b44957 ("regulator: Use
driver_deferred_probe_timeout for regulator_init_complete_work"),
as we ended up reverting the default deferred_probe_timeout
value back to zero, to preserve behavior with 5.6 we need to
decouple the regulator timeout which was previously 30 seconds.
This avoids breaking some systems that depend on the regulator
timeout but don't require the deferred probe timeout.
Cc: linux-pm@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Rob Herring <robh@kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200429172349.55979-1-john.stultz@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mark Brown