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>

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>

While the majority of supplies on devices are mandatory and can't be
physically omitted for electrical reasons some devices do have optional
supplies and need to know if they are missing, MMC being the most common
of these.

Currently the core accurately reports all errors when regulators are
requested since it does not know if the supply is one that must be provided
even if by a regulator software does not know about or if it is one that
may genuinely be disconnected. In order to allow this behaviour to be
changed and stub regulators to be provided in the former case add a new
regulator request function regulator_get_optional() which provides a hint
to the core that the regulator may genuinely not be connected.

Currently the implementation is identical to the current behaviour, future
patches will add support in the core for returning stub regulators in the
case where normal regulator_get() fails and the board has requested it.
Signed-off-by: NMark Brown <broonie@linaro.org>
Acked-by: NChris Ball <cjb@laptop.org>

The dev_attrs field of struct class is going away soon, dev_groups
should be used instead.  This converts the regulator class code to use
the correct field.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Clearly the testing only covered the bottom range.
Signed-off-by: NMark Brown <broonie@linaro.org>

Current code does not allow fixed voltage range in multiple linear ranges.
If someone does set range->uV_step == 0 in one of the linear ranges, we hit
divided by zero bug. This patch fixes this issue.
For fixed voltage range, return any selector means the same voltage.
Thus just return 0.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

There is no need to use a normal per-CPU workqueue for delayed power downs
as they're not timing or performance critical and waking up a core for them
would defeat some of the point.
Signed-off-by: NMark Brown <broonie@linaro.org>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NLiam Girdwood <liam.r.girdwood@intel.com>

In function _regulator_do_set_voltage(), old_selector gets intialised only
if (_regulator_is_enabled(rdev) && rdev->desc->ops->set_voltage_time_sel &&
rdev->desc->ops->get_voltage_sel)) is true.

Before calling set_voltage_time_sel() we checks if (old_selector >= 0) and it
will true if it got intialised properly. so we don't need to check again
_regulator_is_enabled(rdev) && rdev->desc->ops->set_voltage_time_sel before
calling set_voltage_time_sel().
Signed-off-by: NYadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

Many regulators have several linear ranges of selector with different
step sizes, for example offering better resolution at lower voltages.
Provide regulator_{map,list}_voltage_linear_range() allowing these
regulators to use generic code. To do so a table of regulator_linear_range
structs needs to be pointed to from the descriptor.

This was inspired by similar code included in a driver submission from
Chao Xie and Yi Zhang at Marvell.
Signed-off-by: NMark Brown <broonie@linaro.org>

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

Add regulator_get_linear_step(), which returns the voltage step size
between VSEL values for linear regulators.  This is intended for use
by regulator consumers which build their own voltage-to-VSEL tables.
Signed-off-by: NPaul Walmsley <pwalmsley@nvidia.com>
Reviewed-by: NAndrew Chew <achew@nvidia.com>
Cc: Matthew Longnecker <mlongnecker@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add a couple kernel-doc lines to get rid of kernel-doc generation
warnings, no functional change.
Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

A lot of regulator hardware has ascendant voltage list.
This patch adds regulator_map_voltage_ascend() and export it.

Drivers that have ascendant voltage list can use this as their map_voltage()
operation, this is more efficient than default regulator_map_voltage_iterate()
function.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

commit 6d191a5f
(regulator: core: Don't defer probe if there's no DT binding for a supply)

Attempted to differentiate between regulator_get() with an actual
DT binding for the supply and when there is none to avoid unnecessary
deferal.
However, ret value supplied by regulator_dev_lookup() is being
ignored by regulator_get(). So, exit with the appropriate return value.
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Regulator drivers may specify regulator_desc->supply_name which
regulator_register() will use to find the supply node for a regulator.
If no supply was specified in the device tree or the supply has yet
to be registered regulator_register() will fail, deferring the probe
of the regulator.  In the case where no supply node was specified in the
device tree, there is no supply and it is pointless to try and find one
later, so go ahead and add the regulator without the supply.
Signed-off-by: NAndrew Bresticker <abrestic@chromium.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add enable_is_inverted flag to indicate set enable_mask bits to disable
when using regulator_enable_regmap and friends APIs.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Reviewed-by: NHaojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

 The regulator_dev has regulator_enable_gpio structure.
 'ena_gpio' and 'ena_gpio_invert' were moved to in regulator_enable_gpio.

  regulator_dev   --->   regulator_enable_gpio
  .ena_gpio              .gpio
  .ena_gpio_invert       .ena_gpio_invert

  Pointer, 'ena_pin' is used for checking valid enable GPIO pin.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Reviewed-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

 To support shared enable GPIO pin, replace GPIO code with new static functions

 Reference count: 'enable_count'
   Balance the reference count of each GPIO and actual pin control.
   The count is incremented with enabling GPIO.
   On the other hand, it is decremented on disabling GPIO.
   Actual GPIO pin is enabled at the initial use.(enable_count = 0)
   The pin is disabled if it is not used(shared) any more. (enable_count <=1)
   Regardless of the enable count, update GPIO state of the regulator.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Reviewed-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

 A Regulator can be enabled by external GPIO pin.
 This is configurable in the regulator_config.
 At this moment, the GPIO can be owned by only one regulator device.
 In some devices, multiple regulators are enabled by shared one GPIO pin.
 This patch extends this limitation, enabling shared enable GPIO of regulators.

 New list for enable GPIO: 'regulator_ena_gpio_list'
   This manages enable GPIO list.

 New structure for supporting shared enable GPIO: 'regulator_enable_gpio'
   The enable count is used for balancing GPIO control count.
   This count is incremented when GPIO is enabled.
   On the other hand, it's decremented when GPIO is disabled.

 Reference count: 'request_count'
   The reference count, 'request_count' is incremented/decremented on
   requesting/freeing the GPIO. This count makes sure only free the GPIO
   when it has no users.

 How it works
   If the GPIO is already used, skip requesting new GPIO usage.
   The GPIO is new one, request GPIO function and add it to the list of
   enable GPIO.
   This list is used for balancing enable GPIO count and pin control.

 Updating a GPIO and invert code moved
   'ena_gpio' and 'ena_gpio_invert' of the regulator_config were moved to
    new function, regulator_ena_gpio_request().
    Use regulator_enable_pin structure rather than regulator_dev.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Reviewed-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>