regulator: Implement uv_survival_time for handling under-voltage events

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>

regulator: Introduce handling for system-critical under-voltage events

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>

regulator: core: Use different devices for resource allocation and DT lookup

Following by the below discussion, there's the potential UAF issue
between regulator and mfd.
https://lore.kernel.org/all/20221128143601.1698148-1-yangyingliang@huawei.com/

From the analysis of Yingliang

CPU A |CPU B
mt6370_probe() |
devm_mfd_add_devices() |
|mt6370_regulator_probe()
| regulator_register()
| //allocate init_data and add it to devres
| regulator_of_get_init_data()
i2c_unregister_device() |
device_del() |
devres_release_all() |
// init_data is freed |
release_nodes() |
| // using init_data causes UAF
| regulator_register()

It's common to use mfd core to create child device for the regulator.
In order to do the DT lookup for init data, the child that registered
the regulator would pass its parent as the parameter. And this causes
init data resource allocated to its parent, not itself. The issue happen
when parent device is going to release and regulator core is still doing
some operation of init data constraint for the regulator of child device.

To fix it, this patch expand 'regulator_register' API to use the
different devices for init data allocation and DT lookup.

Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://lore.kernel.org/r/1670311341-32664-1-git-send-email-u0084500@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: fix a NULL vs IS_ERR() check in of_regulator_bulk_get_all()

The regulator_get() function never returns NULL. It returns error pointers.

Fixes: 27b9ecc7a9ba ("regulator: Add of_regulator_bulk_get_all")
Signed-off-by: Peng Wu <wupeng58@huawei.com>
Link: https://lore.kernel.org/r/20221122082242.82937-1-wupeng58@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add of_regulator_bulk_get_all

It work exactly like regulator_bulk_get() but instead of working on a
provided list of names, it seek all consumers properties matching
xxx-supply.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Link: https://lore.kernel.org/r/20221115073603.3425396-2-clabbe@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Fix kernel-doc

drivers/regulator/of_regulator.c:689: warning: expecting prototype for of_parse_coupled regulator(). Prototype was for of_parse_coupled_regulator() instead.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2205#c0
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220919024830.111874-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Fix refcount leak bug in of_get_regulation_constraints()

We should call the of_node_put() for the reference returned by
of_get_child_by_name() which has increased the refcount.

Fixes: 40e20d68bb3f ("regulator: of: Add support for parsing regulator_state for suspend state")
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220715111027.391032-1-windhl@126.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: add property parsing and callbacks to set protection limits

Add DT property parsing code and setting callback for regulator over/under
voltage, over-current and temperature error limits.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/e7b8007ba9eae7076178bf3363fb942ccb1cc9a5.1622628334.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Avoid a double 'of_node_get' in 'regulator_of_get_init_node()'

'for_each_available_child_of_node()' already performs an 'of_node_get()'
on child, so there is no need to perform another one before returning.
Otherwise, a double 'get' is performed and a resource may never be
released.

Fixes: 925c85e21ed8 ("regulator: Factor out location of init data OF node")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/a79f0068812b89ff412d572a1171f22109c24132.1618947049.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: add of_match_full_name boolean flag

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>

regulator: of_regulator: Add missing colon for rdev kerneldoc argument

Kerneldoc validation gets confused if syntax isn't "@.*: ".

Adding the missing colons squashes the following W=1 warnings:

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Rajendra Nayak <rnayak@ti.com>
Link: https://lore.kernel.org/r/20200708124832.3441649-3-lee.jones@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: make regulator_register() EPROBE_DEFER aware

Sometimes it can happen that the regulator_of_get_init_data() can't
retrieve the config due to a not probed device the regulator depends on.
Fix that by checking the return value of of_parse_cb() and return
EPROBE_DEFER in such cases.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Link: https://lore.kernel.org/r/20190917154021.14693-4-m.felsch@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: fix suspend-min/max-voltage parsing

Currently the regulator-suspend-min/max-microvolt must be within the
root regulator node but the dt-bindings specifies it as subnode
properties for the regulator-state-[mem/disk/standby] node. The only DT
using this bindings currently is the at91-sama5d2_xplained.dts and this
DT uses it correctly. I don't know if it isn't tested but it can't work
without this fix.

Fixes: f7efad10b5c4 ("regulator: add PM suspend and resume hooks")
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Link: https://lore.kernel.org/r/20190917154021.14693-3-m.felsch@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add of_node_put() before return in function

The local variable search in regulator_of_get_init_node takes the value
returned by either of_get_child_by_name or of_node_get, both of which
get a node. If this node is not put before returning, it could cause a
memory leak. Hence put search before a mid-loop return statement.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Link: https://lore.kernel.org/r/20190724083231.10276-1-nishkadg.linux@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers: Introduce device lookup variants by of_node

Introduce wrappers for {bus/driver/class}_find_device() to
locate devices by its of_node.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: dri-devel@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: devicetree@vger.kernel.org
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: linux-i2c@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-spi@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Alan Tull <atull@kernel.org>
Cc: linux-fpga@vger.kernel.org
Cc: Peter Rosin <peda@axentia.se>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Thor Thayer <thor.thayer@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Peter Rosin <peda@axentia.se>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # I2C part
Acked-by: Moritz Fischer <mdf@kernel.org> # For FPGA part
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20190723221838.12024-3-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

regulator: core: Introduce API for regulators coupling customization

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>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 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 as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

regulator: of: Make regulator_of_get_init_node static

Fix sparse warning:

drivers/regulator/of_regulator.c:374:20:
warning: symbol 'regulator_of_get_init_node' was not declared. Should it be static?

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Fix trivial language typos

Fix few trivial language typos in core and drivers.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Allow regulator nodes to contain their own init data

Currently it is expected that regulator init data will be defined as a
series of sub-nodes from the node that bound in the driver. Add support
for a node to both bind in a driver and contain init data for that
regulator.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Factor out location of init data OF node

To support future additions factor out the location of the OF node
containing the init data for the regulator from the code that parses the
init data.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: add support for parsing regulator-state-standby

Set the according constraints for PM_SUSPEND_STANDBY case.
Previously, only suspend to mem/disk were taken into
consideration.

Signed-off-by: Andrei Stefanescu <andrei.stefanescu@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Add new max_uV_step constraint

On NVIDIA Tegra30 there is a requirement for regulator "A" to have voltage
higher than voltage of regulator "B" by N microvolts, the N value changes
depending on the voltage of regulator "B". This is similar to min-spread
between voltages of regulators, the difference is that the spread value
isn't fixed. This means that extra carefulness is required for regulator
"A" to drop its voltage without violating the requirement, hence its
voltage should be changed in steps so that its couple "B" could follow
(there is also max-spread requirement).

Add new "max_uV_step" constraint that breaks voltage change into several
steps, each step is limited by the max_uV_step value.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Fix 'do-nothing' value for regulators without suspend state

Some regulators don't have all states defined and in such cases regulator
core should not assume anything. However in current implementation
of of_get_regulation_constraints() DO_NOTHING_IN_SUSPEND enable value was
set only for regulators which had suspend node defined, otherwise the
default 0 value was used, what means DISABLE_IN_SUSPEND. This lead to
broken system suspend/resume on boards, which had simple regulator
constraints definition (without suspend state nodes).

To avoid further mismatches between the default and uninitialized values
of the suspend enabled/disabled states, change the values of the them,
so default '0' means DO_NOTHING_IN_SUSPEND.

Fixes: 72069f9957a1: regulator: leave one item to record whether regulator is enabled
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

regulator: Convert to using %pOFn instead of device_node.name

In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Parse coupled regulators properties

On Odroid XU3/4 and other Exynos5422 based boards there is a case, that
different devices on the board are supplied by different regulators
with non-fixed voltages. If one of these devices temporarily requires
higher voltage, there might occur a situation that the spread between
devices' voltages is so high, that there is a risk of changing
'high' and 'low' states on the interconnection between devices powered
by those regulators.

Add new structure "coupling_desc" to regulator_dev, which contains
pointers to all coupled regulators including the owner of the structure,
number of coupled regulators and counter of currently resolved
regulators.

Add of_functions to parse all data needed in regulator coupling.
Provide method to check DTS data consistency. Check if each coupled
regulator's max_spread is equal and if their lists of regulators match.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: add support for allowed modes configuration

Add support for configuring the machine constraints
valid_modes_mask element based on a list of allowed modes
specified via a device tree property.

Signed-off-by: David Collins <collinsd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Don't return or expect -errno from of_map_mode()

In of_get_regulation_constraints() we were taking the result of
of_map_mode() (an unsigned int) and assigning it to an int. We were
then checking whether this value was -EINVAL. Some implementers of
of_map_mode() were returning -EINVAL (even though the return type of
their function needed to be unsigned int) because they needed to
signal an error back to of_get_regulation_constraints().

In general in the regulator framework the mode is always referred to
as an unsigned int. While we could fix this to be a signed int (the
highest value we store in there right now is 0x8), it's actually
pretty clean to just define the regulator mode 0x0 (the lack of any
bits set) as an invalid mode. Let's do that.

Fixes: 5e5e3a42c653 ("regulator: of: Add support for parsing initial and suspend modes")
Suggested-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'

If an unlikely failure in 'of_get_regulator_init_data()' occurs, we must
release the reference on the current 'child' node before returning.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Move of_find_regulator_by_node() to of_regulator.c

As of_find_regulator_by_node() is an of function it should be moved from
core.c to of_regulator.c. It provides better separation of device tree
functions from the core and allows other of_functions in of_regulator.c
to resolve device_node to regulator_dev. This will be useful for
implementation of parsing coupled regulators properties.

Declare of_find_regulator_by_node() function in internal.h as well as
regulator_class and dev_to_rdev(), as they are needed by
of_find_regulator_by_node().

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: add PM suspend and resume hooks

In this patch, consumers are allowed to set suspend voltage, and this
actually just set the "uV" in constraint::regulator_state, when the
regulator_suspend_late() was called by PM core through callback when
the system is entering into suspend, the regulator device would act
suspend activity then.

And it assumes that if any consumer set suspend voltage, the regulator
device should be enabled in the suspend state. And if the suspend
voltage of a regulator device for all consumers was set zero, the
regulator device would be off in the suspend state.

This patch also provides a new function hook to regulator devices for
resuming from suspend states.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: leave one item to record whether regulator is enabled

The items "disabled" and "enabled" are a little redundant, since only one
of them would be set to record if the regulator device should keep on
or be switched to off in suspend states.

So in this patch, the "disabled" was removed, only leave the "enabled":
- enabled == 1 for regulator-on-in-suspend
- enabled == 0 for regulator-off-in-suspend
- enabled == -1 means do nothing when entering suspend mode.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE

To make it clear that the symbol in question refers to
suspend-to-idle, rename it from PM_SUSPEND_FREEZE to
PM_SUSPEND_TO_IDLE.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

regulator: of: regulator_of_get_init_data() missing of_node_get()

Boot fails for qcom-apq8074-dragonboard on 4.13-rc1 with error:
OF: ERROR: Bad of_node_put() on /soc/spmi@fc4cf000/pm8941@1/regulators

The error will occur if the configuration is set to:
CONFIG_OF_OVERLAY y
CONFIG_OF_UNITTEST y
CONFIG_OF_DYNAMIC y
CONFIG_OF_RESOLVE y

If CONFIG_OF_DYNAMIC is enabled then of_node_release() detects an
attempt to release a node that is still attached to the device tree.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Allow for asymmetric settling times

Some regulators have different settling times for voltage increases and
decreases. To avoid a time penalty on the faster transition allow for
different settings for up- and downward transitions.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add settling time for non-linear voltage transition

Some regulators (some PWM regulators) have the voltage transition
non-linear i.e. exponentially. On such cases, the settling time
for voltage transition can not be presented in the voltage-ramp-delay.

Add new property for non-linear voltage transition and handle this
in getting the voltage settling time.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: setup initial suspend state

Setup initial suspend state to mem, if suspend state is defined for
mem state. This makes sure that the regulators are in proper mode
already from boot.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Don't flag voltage change as possible for exact voltages

Flagging voltage changes as possible for exactly specified voltages
appears to be triggering bugs in the SDHCI code (it should be able to
handle the case where only one voltage it wants is in the range it is
allowed to set) so make sure we only set the flag in cases where there's
genuine variability.

Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Ensure we are at least in bounds for our constraints

Currently we only attempt to set the voltage during constraints
application if an exact voltage is specified. Extend this so that if
the currently set voltage for the regulator is outside the bounds set in
constraints we will move the voltage to the nearest constraint, raising
to the minimum or lowering to the maximum as needed. This ensures that
drivers can probe without the hardware being driven out of spec.

Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Always flag voltage constraints as appliable

Allow the core to always use the voltage constraints to set the voltage
on startup. A forthcoming change in that code will ensure that we bring
out of constraints voltages into spec with this setting.

Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Use of_property_read_u32() for reading min/max

OF interface provides to read the u32 value via standard interface
of_property_read_u32(). Use this API to read "regulator-min-microvolts"
and "regulator-max-microvolt".

This will make consistent with other property value reads.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: core: Add support for active-discharge configuration

Add support to enable/disable active discharge of regulator via
machine constraints. This configuration is done when setting
machine constraint during regulator register and if regulator
driver implemented the callback ops.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Introduce property to flag set-load support

Introduce "regulator-allow-set-load" property to make it possible to
flag in the board configuration that a regulator is allowed to have the
load requirements changed.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add over current protection (OCP) support

Some regulators can automatically shut down when they detect an
over current event. Add an op (set_over_current_protection) and a
DT property + constraint to support this capability.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add input current limit support

Some regulators can limit their input current (typically annotated
as ilim). Add an op (set_input_current_limit) and a DT property +
constraint to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add soft start support

Some regulators support a "soft start" feature where the voltage
ramps up slowly when the regulator is enabled. Add an op
(set_soft_start) and a DT property + constraint to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add pull down support

Some regulators need to be configured to pull down a resistor
when the regulator is disabled. Add an op (set_pull_down) and a
DT property + constraint to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Add system_load constraint

Some regulators have a fixed load that isn't captured by
consumers that the kernel knows about. Add a constraint to
support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Skip disabled regulator nodes

If a regulator is listed in devicetree, but the node is marked as
"disabled" we should skip parsing the regulator init data and
deny consumers from interacting with the regulator. This
simplifies devicetree maintenance where we can have one dtsi file
with all regulators supported by a PMIC and then select what
regulators are used depending on the board configuration.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Remove unneeded semicolons

Remove unneeded semicolons after the switch statement to satisfy
coccicheck.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Allow parsing custom properties when using simplified DT parsing

When drivers use simplified DT parsing method (they provide
'regulator_desc.of_match') they still may want to parse custom
properties for some of the regulators. For example some of the
regulators support GPIO enable control.

Add a driver-supplied callback for such case. This way the regulator
core parses common bindings offloading a lot of code from drivers and
still custom properties may be used.

The callback, called for each parsed regulator, may modify the
'regulator_config' initially passed to regulator_register().

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add support for parsing initial and suspend modes

Some regulators support their operating mode to be changed on startup
or by consumers when the system is running while others only support
their operating mode to be changed while the system has entered in a
suspend state.

The regulator Device Tree binding documents a set of properties to
configure the regulators operating modes from a FDT. This patch builds
on (40e20d6 regulator: of: Add support for parsing regulator_state for
suspend state) and adds support to parse those properties and fill the
regulator constraints so the regulator core can call the right suspend
handlers when the system enters into sleep.

The modes are defined in the Device Tree using the hardware specific
modes supported by the regulators. Regulator drivers have to define a
translation function that is used to map the hardware specific modes
to the standard ones.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Pass the regulator description in the match table

Drivers can use the of_regulator_match() function to parse the regulator
init_data from DT. A match table is used to specify the name of the node
containing the regulators, the device node and to return the init_data
to the caller.

But also the static regulator descriptor is needed to correctly extract
some DT properties like the regulator initial and suspend modes. Use the
match table to pass that information.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add regulator desc param to of_get_regulator_init_data()

The of_get_regulator_init_data() function is used to extract the regulator
init_data but information on how to extract certain data is defined in the
static regulator descriptor (e.g: how to map the hardware operating modes).

Add a const struct regulator_desc * parameter to the function signature so
the parsing logic could use the information in the struct regulator_desc.

of_get_regulator_init_data() relies on of_get_regulation_constraints() to
actually extract the init_data so it has to pass the struct regulator_desc
but that is modified on a later patch.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add support for parsing microvolts for suspend state

Leverage all the work that was done in (40e20d6 regulator: of: Add
support for parsing regulator_state for suspend state) and throw in
the ability to set suspend microvolts from the device tree.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Staticize 'regulator_states' array

The 'regulator_states' array is used only in this unit and it is not
exported. Make it static.

This also fixes following sparse warning:
drivers/regulator/of_regulator.c:22:12: warning: symbol 'regulator_states' was not declared. Should it be static?

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Lower the severity of the error with no container

Description of regulators should generally be optional so if there is no
DT node for the regulators container then we shouldn't print an error
message. Lower the severity of the message to debug level (it might help
someone work out what went wrong) and while we're at it say what we were
looking for.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Decrement refcount for suspend state nodes

of_get_regulation_constraints() calls of_get_child_by_name() to find the
regulator-state-{mem,disk} child nodes for each regulator. This function
increments the device node reference counter but this is not decremented
once the function is done using the node.

Fix that by calling of_node_put() after finishing using the device node.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Add support for parsing regulator_state for suspend state

The regulation_constraints structure includes specific field to support
suspend state for global PMIC SUSPEND/HIBERNATE mode. This patch add support
for parsing regulator_state for suspend state.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: of: Provide simplified DT parsing method

Currently regulator drivers which support DT all repeat very similar code
to supply a list of known regulator identifiers to be matched with DT,
convert that to platform data which is then matched up with the regulators
as they are registered. This is both fiddly to get right and for devices
which can use the standard helpers to provide their operations is the main
source of code in the driver.

Since this code is essentially identical for most drivers we can factor it
out into the core, moving the identifiers in the match table into the
regulator descriptors and also allowing drivers to pass in the name of the
subnode to search. When a driver provides an of_match string for the
regulator the core will attempt to use that to obtain init_data, allowing
the driver to remove all explicit code for DT parsing and simply provide
data instead.

The current code leaks the phandles for the child nodes, this will be
addressed incrementally and makes no practical difference for FDT anyway
as the DT data structures are never freed.

Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: use of_property_read_{bool|u32}()

Use more compact of_property_read_{bool|u32}() calls instead of the
of_{find|get}_property() calls in of_get_regulation_constraints() where
possible (note that of_property_read_{bool|u32}() were already used to read
some properties).

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: core: Use devres for releasing of_regulator_match of_nodes

Rather than requiring individual drivers to put the of_nodes returned
from of_regulator_match use devres to put them. This also has the
benefit it makes the life-time of the of_nodes match the lifetime of
the init data also contained in the of_regulator_match structure, which
seems more consistent.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: core: Add helper to put of_nodes from matches

As of_regulator_match will take an of_node reference to each matched
regulator, it makes sense to provide a helper to put all those
references. This patch does that.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: core: Add of_node_get to of_regulator_match

Currently, of_regulator_match does not increment the reference count of
the of_nodes it takes new references to. This could cause the node
pointer held to be invalid, by the time it is passed to the regulator
core. This patchs adds an of_node_get when we copy each of_node pointer
into the match structure.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: core: add support for configuring turn-on time through constraints

The turn-on time of the regulator depends on the regulator device's
electrical characteristics. Sometimes regulator turn-on time also
depends on the capacitive load on the given platform and it can be
more than the datasheet value.

The driver provides the enable-time as per datasheet.

Add support for configure the enable ramp time through regulator
constraints so that regulator core can take this value for enable
time for that regulator.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: core: Add support for disabling ramp delay

Some hardwares support disabling ramp delay, so adding ramp_disable flag to
constraints. It will be used to figure out whether ramp_delay in constraints
is explicitly set to zero or its unintialized (zero by default).
And we don't need to call set_voltage_time_sel() for regulators for whom ramp
delay is disabled in constraints.

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: of: Added a property to indicate bypass mode support

Added a property to indicate if the regulator supports bypass mode.
Also modified of_get_regulation_constraints() to check for that
property and set appropriate constraints.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

regulator: clear state each invocation of of_regulator_match

of_regulator_match() saves some dynamcially allocated state into the
match table that's passed to it. By implementation and not contract, for
each match table entry, if non-NULL state is already present,
of_regulator_match() will not overwrite it. of_regulator_match() is
typically called each time a regulator is probe()d. This means it is
called with the same match table over and over again if a regulator
triggers deferred probe. This results in stale, kfree()d data being left
in the match table from probe to probe, which causes a variety of crashes
or use of invalid data.

Explicitly free all output state from of_regulator_match() before
generating new results in order to avoid this.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org

regulator: deprecate regulator-compatible DT property

When the bindings for the TPS6586x regulator were being proposed, I
asserted that DT node naming rules for bus child nodes should also be
applied to nodes inside the TPS6586x regulator node itself. In other
words, that each node providing regulator init data should be named
after the type of object it represented ("regulator") and hence that
some other property was required to indicate which regulator the node
described ("regulator-compatible"). In turn this led to multiple nodes
having the same name, thus requiring node names to use a unit address
to make them unique, thus requiring reg properties within the nodes and

However, subsequent discussion indicates that the rules I was asserting
only applies to standardized bus nodes, and within a device's own node,
the binding can basically do anything sane that it wants.

Hence, this change deprecates the register-compatible property, and
instead uses node names to replace this functionality. This greatly
simplifies the device tree content, making them smaller and more legible.

The code is changed such that old device trees continue to work.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: dt: regulator match by regulator-compatible

Match the device's regulators with the property of
"regulator-compatible" of each regulator node.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: Fix setting constraints->ramp_delay in of_get_regulation_constraints

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: Add ramp_delay configuration to constraints

For some hardwares ramp_delay for BUCKs is a configurable parameter which can
be configured through DT or board file.This patch adds ramp_delay to regulator
constraints and allow user to configure it for regulators which supports this
feature, through DT or board file. It will provide two ways of setting the
ramp_delay for a regulator:
First, by setting it as constraints in board file(for configurable
regulators) and set_machine_constraints() will take care of setting it on
hardware by calling(the provided) .set_ramp_delay() operation(callback).
Second, by setting it as data in regulator_desc(as fixed/default
ramp_delay rate) for a regulator in driver.

regulator_set_voltage_time_sel() will give preference to
constraints->ramp_delay while reading ramp_delay rate for regulator. Similarly
users should also take care accordingly while refering ramp_delay rate(in case
of implementing their private .set_voltage_time_sel() callbacks for different
regulators).

[Rewrote subject for 80 columns -- broonie]

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: Add generic DT parsing for regulators

Looking up init data for regulators found on chips is a common operation
that can be handled in a generic way. The new helper function introduced
by this patch looks up the children of a given node by names specified
in a match table and fills that match table with information parsed from
the DT.

This is based on work by Rhyland Klein <rklein@nvidia.com>.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: Set apply_uV only when min and max voltages are defined

apply_uV is errornously set when regulator is instantiated from device
tree, even when it doesn't contain any voltage constraints.

This commit fixes error:

machine_constraints_voltage: CHARGER: failed to apply 0uV constraint

for following regulator description in DTS:

CHARGER {
regulator-min-microamp = <100000>;
regulator-max-microamp = <200000>;
}

Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: pass device_node to of_get_regulator_init_data()

It's not always true that the device_node of regulator can be found
at dev->of_node at the time when of_get_regulator_init_data() is being
called, because in some cases the regulator nodes in device tree do
not have 'struct device' behind them until regulator_dev gets created
for it by core function regulator_register().

The patch adds device_node as a new parameter to
of_get_regulator_init_data(), so that caller can pass in the node of
regulator directly.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: If a single voltage is set with device tree then set apply_uV

Otherwise there is no way in the bindings to configure a fixed voltage
via software. It seems reasonable to assume that if the binding explicitly
specifies a voltage we want to actually use that voltage.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: export of_get_regulator_init_data

of_get_regulator_init_data is called in drivers/regulator/fixed.c
which could be a module.

Export of_get_regulator_init_data to fix below build error:
ERROR: "of_get_regulator_init_data" [drivers/regulator/fixed.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

regulator: helper routine to extract regulator_init_data

The helper routine is meant to be used by the regulator drivers
to extract the regulator_init_data structure from the data
that is passed from device tree.
'consumer_supplies' which is part of regulator_init_data is not extracted
as the regulator consumer mappings are passed through DT differently,
implemented in subsequent patches.
Similarly the regulator<-->parent/supply mapping is handled in
subsequent patches.

Also add documentation for regulator bindings to be used to pass
regulator_init_data struct information from device tree.

Some of the regulator properties which are linux and board specific,
are left out since its not clear if they can
be in someway embedded into the kernel or passed in from DT.
They will be revisited later.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>