Extend regulator notification support
This series extends the regulator notification and error flag support.
Initial discussion on the topic can be found here:
https://lore.kernel.org/lkml/6046836e22b8252983f08d5621c35ececb97820d.camel@fi.rohmeurope.com/
In a nutshell - the series adds:
1. WARNING level events/error flags. (Patch 3)
Current regulator 'ERROR' event notifications for over/under
voltage, over current and over temperature are used to indicate
condition where monitored entity is so badly "off" that it actually
indicates a hardware error which can not be recovered. The most
typical hanling for that is believed to be a (graceful)
system-shutdown. Here we add set of 'WARNING' level flags to allow
sending notifications to consumers before things are 'that badly off'
so that consumer drivers can implement recovery-actions.
2. Device-tree properties for specifying limit values. (Patches 1, 5)
Add limits for above mentioned 'ERROR' and 'WARNING' levels (which
send notifications to consumers) and also for a 'PROTECTION' level
(which will be used to immediately shut-down the regulator(s) W/O
informing consumer drivers. Typically implemented by hardware).
Property parsing is implemented in regulator core which then calls
callback operations for limit setting from the IC drivers. A
warning is emitted if protection is requested by device tree but the
underlying IC does not support configuring requested protection.
3. Helpers which can be registered by IC. (Patch 4)
Target is to avoid implementing IRQ handling and IRQ storm protection
in each IC driver. (Many of the ICs implementin these IRQs do not allow
masking or acking the IRQ but keep the IRQ asserted for the whole
duration of problem keeping the processor in IRQ handling loop).
4. Emergency poweroff function (refactored out of the thermal_core to
kernel/reboot.c) which is called if IC fires error IRQs but IC reading
fails and given retry-count is exceeded. (Patches 2, 4)
Please note that the mutex in the emergency shutdown was replaced by a
simple atomic in order to allow call from any context.
The helper was attempted to be done so it could be used to implement
roughly same logic as is used in qcom-labibb regulator. This means
amongst other things a safety shut-down if IC registers are not readable.
Using these shut-down retry counters are optional. The idea is that the
helper could be also used by simpler ICs which do not provide status
register(s) which can be used to check if error is still active.
ICs which do not have such status register can simply omit the 'renable'
callback (and retry-counts etc) - and helper assumes the situation is Ok
and re-enables IRQ after given time period. If problem persists the
handler is ran again and another notification is sent - but at least the
delay allows processor to avoid IRQ loop.
Patch 7 takes this notification support in use at BD9576MUF.
Patch 8 is related to MFD change which is not really related to the RFC
here. It was added to this series in order to avoid potential conflicts.
Patch 9 adds a maintainers entry.
Changelog v10-RESEND:
- rebased on v5.13-rc4
Changelog v10:
- rebased on v5.13-rc2
- Move rdev_*() print macros to the internal.h and use rdev_dbg()
from irq_helpers.c
- Export rdev_get_name() and move it from coupler.h to driver.h for
others to use. (It was already in coupler.h but not exported -
usage was limited and coupler.h does not sound like optimal place
as rdev_name is not only used by coupled regulators)
- Send all regulator notifications from irq_helpers.c at one OR'd
event for the sake of simplicity. For BD9576 this does not matter
as it has own IRQ for each event case. Header defining events says
they may be OR'd.
- Change WARN() at protection shutdown to pr_emerg as suggested by
Petr.
Changelog v9:
- rebases on v5.13-rc1
- Update thermal documentation
- Fix regulator notification event number
Changelog v8:
- split shutdown API adding and thermal core taking it in use to
own patches.
- replace the spinlock with atomic when ensuring the emergency
shutdown is only called once.
Changelog v7:
general:
- rebased on v5.12-rc7
- new patch for refactoring the hw-failure reboot logic out of
thermal_core.c for others to use.
notification helpers:
- fix regulator error_flags query
- grammar/typos
- do not BUG() but attempt to shut-down the system
- use BITS_PER_TYPE()
Changelog v6:
Add MAINTAINERS entry
Changes to IRQ notifiers
- move devm functions to drivers/regulator/devres.c
- drop irq validity check
- use devm_add_action_or_reset()
- fix styling issues
- fix kerneldocs
Changelog v5:
- Fix the badly formatted pr_emerg() call.
Changelog v4:
- rebased on v5.12-rc6
- dropped RFC
- fix external FET DT-binding.
- improve prints for cases when expecting HW failure.
- styling and typos
Changelog v3:
Regulator core:
- Fix dangling pointer access at regulator_irq_helper()
stpmic1_regulator:
- fix function prototype (compile error)
bd9576-regulator:
- Update over current limits to what was given in new data-sheet
(REV00K)
- Allow over-current monitoring without external FET. Set limits to
values given in data-sheet (REV00K).
Changelog v2:
Generic:
- rebase on v5.12-rc2 + BD9576 series
- Split devm variant of delayed wq to own series
Regulator framework:
- Provide non devm variant of IRQ notification helpers
- shorten dt-property names as suggested by Rob
- unconditionally call map_event in IRQ handling and require it to be
populated
BD9576 regulators:
- change the FET resistance property to micro-ohms
- fix voltage computation in OC limit setting
Some NVIDIA Tegra devices use a CPU soft-reset method for the reboot and
in this case we need to restore the coupled voltages to the state that is
suitable for hardware during boot. Add new regulator_sync_voltage_rdev()
helper which is needed by regulator drivers in order to sync voltage of
a coupled regulators.
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The jiffies-based off_on_delay implementation has a couple of problems
that cause it to sometimes not actually delay for the required time:
(1) If, for example, the off_on_delay time is equivalent to one jiffy,
and the ->last_off_jiffy is set just before a new jiffy starts,
then _regulator_do_enable() does not wait at all since it checks
using time_before().
(2) When jiffies overflows, the value of "remaining" becomes higher
than "max_delay" and the code simply proceeds without waiting.
Fix these problems by changing it to use ktime_t instead.
[Note that since jiffies doesn't start at zero but at INITIAL_JIFFIES
("-5 minutes"), (2) above also led to the code not delaying if
the first regulator_enable() is called when the ->last_off_jiffy is not
initialised, such as for regulators with ->constraints->boot_on set.
It's not clear to me if this was intended or not, but I've preserved
this behaviour explicitly with the check for a non-zero ->last_off.]
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20210423114524.26414-1-vincent.whitchurch@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>
During regulators registration, if .of_match and .regulators_node are
defined as non-null strings in struct regulator_desc the core searches the
DT subtree rooted at .regulators_node trying to match, at first, .of_match
against the 'regulator-compatible' property and, then, falling back to use
the name of the node itself to determine a good match.
Property 'regulator-compatible', though, is now deprecated and falling back
to match against the node name, works fine only as long as the involved
nodes are named in an unique way across the searched subtree; if that's not
the case, like when using <common-name>@<unit> style naming for properties
indexed via 'reg' property (as advised by the standard), the above matching
mechanism based on the simple common name will lead to multiple matches and
the only viable alternative would be to properly define the now deprecated
'regulator-compatible' as the node full name, i.e. <common-name>@<unit>.
In order to address this case without using such deprecated binding, define
a new boolean flag .of_match_full_name in struct regulator_desc to force
the core to match against the node full-name instead of the plain name.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20201119191051.46363-4-cristian.marussi@arm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Silence documentation build warning by correcting kernel-doc comments.
./include/linux/regulator/machine.h:196: warning: Function parameter or member 'max_uV_step' not described in 'regulation_constraints'
./include/linux/regulator/driver.h:206: warning: Function parameter or member 'resume' not described in 'regulator_ops'
Signed-off-by: Colton Lewis <colton.w.lewis@protonmail.com>
Link: https://lore.kernel.org/r/20200715191438.29312-1-colton.w.lewis@protonmail.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>
The toolchain produces a warning on this driver when building
the docs:
./include/linux/regulator/driver.h:284: WARNING: Unknown target name: "regulator_regmap_x_voltage".
While fixing it, we notices that there's no function names
with the above pattern. It seems that some previous patch
renamed it to regulator_map_* instead.
So, change the function name, replacing "x" by "*", with is
a more used way to add a wildcard, and escape those with
``literal`` markup, in order to avoid the toolchain to think
that this is a link to some existing document chapter.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/b9f5687bcf981a88c9d1fd04d759a540fda53a99.1584456635.git.mchehab+huawei@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Some regulators require that the requested voltage be reached gradually
by setting all or some of the intermediate values. Implement a new field
in the regulator description struct that allows users to specify the
number of selectors by which the regulator API should step when ramping
the voltage up/down.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20190703161035.31808-2-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Right now regulator core supports only one type of regulators coupling,
the "voltage max-spread" which keeps voltages of coupled regulators in a
given range from each other. A more sophisticated coupling may be required
in practice, one example is the NVIDIA Tegra SoCs which besides the
max-spreading have other restrictions that must be adhered. Introduce API
that allow platforms to provide their own customized coupling algorithms.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By setting curr_table, n_current_limits, csel_reg and csel_mask, the
regmap users can use regulator_set_current_limit_regmap and
regulator_get_current_limit_regmap for set/get_current_limit callbacks.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The csel_reg and csel_mask fields in struct regulator_desc needs to
be generic for drivers. Not just for TPS65218.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add regulator_desc_list_voltage_linear_range which can be used
by drivers for getting the voltages before regulator is registered.
This may be useful for drivers which need to fetch the voltage
selectors at device-tree parsing callback.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Mark Brown <broonie@kernel.org>
Tested-by: Angus Ainslie <angus@akkea.ca>
Reviewed-by: Angus Ainslie <angus@akkea.ca>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now that we changed all providers to pass descriptors into the core
for enable GPIOs instead of a global GPIO number, delete the support
for passing GPIO numbers in, and we get a cleanup and size reduction
in the core, and from a GPIO point of view we use the modern, cleaner
interface.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In general when the consumer of a regulator requests that the
regulator be disabled it no longer will be drawing much load from the
regulator--it should just be the leakage current and that should be
very close to 0.
Up to this point the regulator framework has continued to count a
consumer's load request for disabled regulators. This has led to code
patterns that look like this:
enable_my_thing():
regular_set_load(reg, load_uA)
regulator_enable(reg)
disable_my_thing():
regulator_disable(reg)
regulator_set_load(reg, 0)
Sometimes disable_my_thing() sets a nominal (<= 100 uA) load instead
of setting a 0 uA load. I will make the assertion that nearly all (if
not all) places where we set a nominal load of 100 uA or less we end
up with a result that is the same as if we had set a load of 0 uA.
Specifically:
- The whole point of setting the load is to help set the operating
mode of the regulator. Higher loads may need less efficient
operating modes.
- The only time this matters at all is if there is another consumer of
the regulator that wants the regulator on. If there are no other
consumers of the regulator then the regulator will turn off and we
don't care about the operating mode.
- If there's another consumer that actually wants the regulator on
then presumably it is requesting a load that makes our nominal
<= 100 uA load insignificant.
A quick survey of the existing callers to regulator_set_load() to see
how everyone uses it:
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
