Load switches are modeled as regulators but they just provide
the voltage of their parent input supply. So, the drivers for
these switches usually neither provide a .list_voltage handler
not set a .n_voltages count. But there is code in the kernel
that assumes that all regulators should be able to provide this
information (e.g: cpufreq and mmc subsystems).

If the voltage count and list are not available for a regulator
and it has a parent input supply, then use the parent values.
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: NMark Brown <broonie@linaro.org>

Load switches are modeled as regulators but they just provide
the voltage of their parent input supply. So the drivers for
these switches usually don't provide a .get_voltage function
handler but there is code in the kernel that assumes that all
regulators should be able to provide its current voltage rail.

So, if the output voltage for a regulator is not available and
it has a parent supply, then pass the voltage of its parent.
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: NMark Brown <broonie@linaro.org>

With commit 064d5cd1
(regulator: core: Fix the init of DT defined fixed regulators)
We ensure that regulator must be capable of providing it's current
voltage when constraints are used, however adding the return value in
the print is a little more informative to explain the nature of the
failure involved.

So, instead of providing message such as:
smps9: failed to get the current voltage

having error value added to the message such as:
smps9: failed to get the current voltage(-22)

is a little more informative for debugging the error.
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

When a regulator is defined using DT and it has a single voltage the
regulator init always tries to apply this voltage. However it fails if
the regulator isn't settable because it is using an internal low level
function. To overcome this we now first query the regulator and only
set it if needed.
Signed-off-by: NAlban Bedel <alban.bedel@avionic-design.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

regulator_init_complete does a scan of regulators which dont have
always-on or consumers are automatically disabled as being unused.
However, with deferred probing, late_initcall() is too soon to
declare a regulator as unused as the regulator itself might not
have registered due to defferal - Example: A regulator deffered due
to i2bus not available which in turn is deffered due to pinctrl
availability.

Since deferred probing is done in late_initcall(), do the cleanup of
unused regulators by regulator_init_complete in late_initcall_sync
instead of late_initcall.

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NSaravana Kannan <skannan@codeaurora.org>
[nm@ti.com: minor rewording]
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

In the spirit of conservatism that governs our general approach to
permissions it is better if we don't touch regulators we weren't explicitly
given permissions to control. This avoids the need to explicitly specify
unknown regulators in DT as always on, if a regulator is not otherwise
involved in software control it can be omitted from the DT.

Regulators explicitly given constraints in DT still need to have an always
on constraint specified as before.
Signed-off-by: NMark Brown <broonie@linaro.org>

regulator_get_optional() doesn't hold an exclusive reference to
the regulator. Fix the documentation and reword the exclusive
documentation to fix the grammatical error "this reference is
held".
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Use map_voltage_linear_range() if list_voltage_linear_range() is in use and
nothing is set.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Toughen-up checks for read-only regulator names.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Currently the regulator core does not take an additional reference to
the of_node it is passed. This means that the caller must ensure that
the of_node is valid for the duration of the regulator's existance.
It is reasonable for the framework to assume it is passed a valid
of_node but seems onerous for it to assume the caller will keep the node
valid for the life-time of the regulator, especially when
devm_regulator_register is used and there will likely be no code in the
driver called at the point it would be safe to put the of_node.

This patch adds an additional of_node_get when the regulator is
registered and an of_node_put when it is unregistered in the core. This
means individual drivers are free to put their of_node references at the
end of probe letting the regulator core handling it from there. This
simplifies code on the driver side.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

There are many places where ops->disable is called directly. Instead we
should use _regulator_do_disable() which also handles gpio regulators.

To be able to use the wrapper function from _regulator_force_disable(),
I moved the _notifier_call_chain() call from _regulator_do_disable() to
_regulator_disable(). This way, _regulator_force_disable() can use
different flags for _notifier_call_chain() without calling it twice.

Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

There are some direct ops->enable in the regulator core driver. This is
a potential issue as the function _regulator_do_enable() handles gpio
regulators and the normal ops->enable calls. These gpio regulators are
simply ignored when ops->enable is called directly.

One possible bug is that boot-on and always-on gpio regulators are not
enabled on registration.

This patch replaces all ops->enable calls by _regulator_do_enable.

[Handle missing enable operations -- broonie]

Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

regulator: Handle invalid enable operation for always/boot on regulators
Signed-off-by: NMark Brown <broonie@linaro.org>

Change "dummy supplies not allowed" error message to warning instead, as this
is a just warning message with no change to the behavior.

[Added a CC to stable since some other bug fixes cause this to come up
more frequently on PCs which is how it was noticed -- broonie]
Signed-off-by: NShuah Khan <shuah.kh@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org

This patch fix spelling typo in Documentation/DocBook.
It is because .html and .xml files are generated by make htmldocs,
I have to fix a typo within the source files.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Make it okay to call regulator_set_voltage on regulators with fixed
voltage if the requested range overlaps the current/configured voltage.
Signed-off-by: NBjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Once we have full constraints then all supply mappings should be known to
the regulator API. This means that we should treat failed lookups as fatal
rather than deferring in the hope of further registrations but this was
broken by commit 9b92da1f "regulator: core: Fix default return
value for _get()" which was targeted at DT systems but unintentionally
broke non-DT systems by changing the default return value.

Fix this by explicitly returning -EPROBE_DEFER from the DT lookup if we
find a property but no corresponding regulator and by having the non-DT
case default to -ENODEV when we have full constraints.

Fixes: 9b92da1f "regulator: core: Fix default return value for _get()"
Signed-off-by: NMark Brown <broonie@linaro.org>
Tested-by: NGuenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org

Fix the following checkpatch errors and warnings.

  ERROR: trailing whitespace
  ERROR: return is not a function, parentheses are not required
  WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Only print an error when _regulator_get() is expected to return a valid
regulator, that is when _regulator_get() is called from regulator_get() and
we're not using the dummy because we don't have full-constraints, or when
_regulator_get() is called from regulator_get_exclusive() in which case
returning a dummy is not allowed.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Eliminate the gap between DT becoming available and this being used to say
we have full constraints by checking directly for DT every time we check
for full constraints. This improves interoperaton with optional regulator
support.
Signed-off-by: NMark Brown <broonie@linaro.org>
Tested-by: NFabio Estevam <fabio.estevam@freescale.com>

Simple code reorganisation so we can change the logic for deciding what
full constraints are more easily.
Signed-off-by: NMark Brown <broonie@linaro.org>

Commit c368e5fc "regulator: fixed:
get rid of {get|list}_voltage()" broke regulator_list_voltage() for
the fixed regulator, because an earlier commit
5a523605 "regulator: core: provide
fixed voltage in desc for single voltage rail" missed to add support
for the fixed-voltage special case to that function. This patch
fixes that regression.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

These patches add the ability to create an alternative device on which
a lookup for a certain supply should be conducted.

A common use-case for this would be devices that are logically
represented as a collection of drivers within Linux but are are
presented as a single device from device tree. It this case it is
necessary for each sub device to locate their supply data on the main
device.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

This helps people spot if they have missed a supply from a device tree or
equivalent data structure.
Suggested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Keep busy-wait looping to a minimum while waiting for a regulator to
ramp-up to the target voltage. This follows the guidelines set forth
in Documentation/timers/timers-howto.txt and assumes that regulators
are never enabled in atomic context.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Ensure that the return value is always set when we return now that the
logic has changed for regulator_get_optional() so we don't get missing
codes leaking out.
Reported-by: NThierry Reding <treding@nvidia.com>
Tested-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

We should be returning an error, a repeated call will never succeed.
Signed-off-by: NMark Brown <broonie@linaro.org>

Now that we are defaulting to providing dummy regulators fix the logic
for substituting a dummy by making the default return code -EPROBE_DEFER.
Reported-by: NThierry Reding <treding@nvidia.com>
Tested-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Machine constraints is configured during regulator register. If current
constraints are provided through machine constraints then it is observed
that sometime the current configured on rail is out of range what machine
constraint has.

Set the current constraints when setting machine constraints to make
sure that rail's current is within the range of given machine constraints.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

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: NLaxman Dewangan <ldewangan@nvidia.com>
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

No boards have used this functionality and the new default of providing
dummy regulators by default provides a better solution to the problem it
was trying to solve.
Signed-off-by: NMark Brown <broonie@linaro.org>

When a system has said that it has fully specified constraints for its
regulators it is still possible that some supplies may be missing,
especially if regulator support has been added to a driver after the
board was integrated. We can handle such situations more gracefully by
providing a dummy regulator.

Unless the caller has specifically indicated that the system design may
not include a given regulator by using regulator_get_optional() or that
it needs its interactions to have an effect using regulator_get_exclusive()
provide a dummy regulator if we can't locate a real one.

The kconfig option REGULATOR_DUMMY that provided similar behaviour for all
regulators has been removed, systems that need it should flag that they
have full constraints instead.
Signed-off-by: NMark Brown <broonie@linaro.org>

Cut down on the size of core.c a bit more and ensure that the devres
versions of things don't do too much peering inside the internals of
the APIs they wrap.
Signed-off-by: NMark Brown <broonie@linaro.org>

The implementation of devm_regulator_get, devm_regulator_get_exclusive and
devm_regulator_get_optional are almost the same.
Introduce _devm_regulator_get helper function and refactor the code.

Also move devm_regulator_get_exclusive to proper place, put it after
regulator_get_exclusive() function.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Changed automaticall -> automatically.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Many regulator drivers have a remove function that consists solely of
calling regulator_unregister() so provide a devm_regulator_register()
in order to allow this repeated code to be removed and help eliminate
error handling code.
Signed-off-by: NMark Brown <broonie@linaro.org>

If given rail has the single voltage (n_voltages = 1) then provide the
rail voltage through regulator descriptor so that core can use this
value for finding voltage.

This will avoid the implementation of the callback for get_voltage() or
list_voltage() callback on regulator driver.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Add a resource managed regulator_get_exclusive()
Signed-off-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: NMark Brown <broonie@linaro.org>

Just for neatness.
Signed-off-by: NMark Brown <broonie@linaro.org>

Move regulator_list_voltage_{linear,linear_range,table} helper functions to
helpers.c.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Reduce the size of core.c a bit.
Signed-off-by: NMark Brown <broonie@linaro.org>